contents - undpgefpims.org … · web viewpoor water quality has led to increased health issues...

Annex II – Feasibility Study

GREEN CLIMATE FUND FUNDING PROPOSAL

I am keeping this one! :)

Annex II - Feasibility study:

Ensuring climate resilient water supplies in the Comoros

Islands

I

CONTENTS

Contents 2

List of Acronyms 7

Executive Summary 8

1. Climate risk profile of the Comoros 91.1 Country background 91.1.1 Introduction 91.1.2 Population 91.1.3 Current political structure 101.1.4 Economic setting 101.1.5 Livelihoods 101.1.6 Water resources 111.1.7 Access to water 131.1.8 Water quality and public health impact 131.1.9 Water Supply Service Providers 141.1.10 Willingness to Pay 141.1.11 Existing Water Supply Shortages 151.1.12 Economic implications 161.1.13 Gender aspects 161.2 Climate Change in the Comoros: Risks and Impacts 171.2.1 Baseline climate 171.2.2 Observed effects of climate change 171.2.3 Predicted climate change 201.3 Overview of Vulnerabilities and impacts of climate change on the water sector 241.4 Climate Change Risks and Impacts on Rainwater Harvesting 261.4.1 Household Rainwater Harvesting 261.4.2 Communal Rainwater Harvesting 301.4.3 Volcanic Rainwater Impluviums 311.5 Climate Change Risk and Impacts on Groundwater Resources 381.5.1 Groundwater on Grand Comore 401.5.2 Groundwater on Anjouan 511.5.3 Groundwater on Moheli 541.6 Climate Change Risk and Impacts on Surface Water Resources 561.6.1 Surface Water on Anjouan 571.6.2 Surface Water on Moheli 631.7 Climate Vulnerability Mapping and Target Zone Selection 651.7.1 Climate vulnerability distribution mapping process 651.7.2 Target villages 65

Policy and institutional frameworks related to climate change adaptation, water and sanitation 682.1 Overview 68

2

2.2 National development policies 692.2.1 National climate change policy 692.2.2 National climate change adaptation plan 692.2.3 The Intended Nationally Determined Contribution of the Comoros 702.2.4 National policy on water supply and sanitation 702.3 Water-related institutional arrangements of Comoros 712.3.1 Current administrative organization 712.3.2 Weaknesses of the Water Code prior to 2015 Reform 722.3.3 Water Code Reform 73

Synergies and complementarities of the programme with other projects / programmes 783.1 Overview of past and on-going projects 783.1.1 Water Management 783.1.2 IWRM 793.1.3 Drinking water supply 793.1.4 Climate Change Resilience 813.1.5 Gender integration 813.2 Integration of best practices and lessons learned from implemented and on-going projects 823.2.1 Comoros project lessons 823.2.2 Global SIDS best practise 823.3 Gaps in service and coverage of past and on-going projects 83

Barriers to achieving climate resilience and adaptation options 854.1 Key barriers to achieving climate resilient water supplies 854.2 Recommended Climate Change Adaptation Options 894.2.1 National Water Sector Climate Change Resilience Actions 894.2.2 Recommended water supply climate resilience infrastructure actions on Grand Comore 914.2.3 Recommended water supply climate resilience actions on Anjouan and Moheli 98

Proposed project interventions given current gaps and needs 1065.1 Output 1: Water supply sectoral climate risk reduction planning and management 1075.1.1 Activity 1.1: Integrating Climate Risks into the national water sector legislation, financing and

planning processes 1085.1.2 Activity 1.2: Strengthening water providers on climate risk reduction water climate risk

reduction design, operation & maintenance 1095.2 Output 2: Climate Informed Water Resources and Watershed Monitoring and Risk Forecasting 1105.2.1 Output 2.1: Strengthening Watershed Management and Eco-system Based Adaptation Planning

and Implementation 1115.2.2 Output 2.2: Watershed Adaptation Legislation and Public Awareness Raising 1125.2.3 Output 2.3: Water resources management and monitoring, hazard and risk assessment and

drought and flood forecasting 1135.2.4 Output 2.4: Climate adaptation products generation using hydrological forecasts and sector

application 1145.3 Output 3: Climate resilient water supply infrastructure 1145.3.1 Activity 3.1: Climate Risk Reduction of Existing Groundwater Boreholes and Expansion of

Groundwater Exploitation 1163

5.3.2 Activity 3.2: Climate Risk Reduction Upgrades and Extensions to Water Supply Networks 1165.3.3 Output 3.3: Installation of Flow Meters to inform Climate Risk Reinvestment Tariff Setting and

Leakage reduction 1175.4 Consideration of gender 1185.5 Targets and indicators 1185.6 Expected environmental and social benefits and co-benefits 1195.7 Knowledge management and learning 1225.8 Institutional framework for Project Implementation 1235.9 Institutions at national and state levels 1255.10 Stakeholder and Community Engagement 126

Conclusions 126

References 128

FIGURES

Figure 1: Map of Year Round River Flow in AnjouanFigure 2: Cases of typhoid and diarrheal disease in Anjouan in 2010 and 2011Figure 3: 12 month percentile rank of draught data from 1960 – 2015Figure 4: Seasonal precipitation projections in the Comoros from 1960 to 2100 (UNEP)

Figure 5: Mean temperature anomaly annual in the Comoros from 1960 to 2100 (UNEP)

Figure 6: Rainwater harvesting storage, person demand 35 lpd, storage capacity 47m3

Figure 7: Rainwater harvesting storage, person demand 20 lpd, storage capacity 47 m3

Figure 8: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 2.5 l/m2/dFigure 9: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.0 l/m2/dFigure 10: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.5l/m2/dFigure 11: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.5l/m2/d and the captured rainfall at 70%.Figure 12: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.5l/m2/d and the soil holding capacity at 250 l/m2.Figure 13: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.5l/m2/d, rainfall captured at 70% and the soil holding capacity at 250 l/m2.Figure 14: Schematic of conceptual models of Hawaiianand Canarian type volcanic craters and their related ground water occurrence.Figure 15: Location of boreholes that were implemented by UN agencies and managed by the MAMWE108

Figure 16: Map of geology and hydrogeology of Grande Comore109

Figure 17: Pressure and salinity dataloggers records in the coastal wells at (a) well SHA at Hahaya, (b) well TP5 at Vouvouni and (c) well ONU 40 at Oichili.Figure 18: More detailed datalogger time series for the wells near Hahaya.Figure 19: Map of water samples locations is shown below on Anjouan111

Figure 20: Hydrograph of Pomoni alluvial floodplain well 111.Figure 21: Previously identified possible exploratory borehole locations in Anjouan.Figure 22: Previously identified possible exploratory borehole locations in Moheli

4

Figure 23: Map of the 44 watershed basins on Anjouan as identified in the NWSPFigure 24: Normalised flows in Mutsamudu Watershed tributaries 112.Figure 25: Hydrograph for 2010-2011 at the Daji Intake Captage just south of Adda113.Figure 26: Map of changes in year round flowing streams on AnjouanFigure 27: 12 month percentile rank of draught data from 1960 – 2015Figure 28: 3 month percentile rank of draught data from 2000 – 2015Figure 29: Map of 25 watersheds on Moheli.Figure 30: Location map of the target communes on all three islands (Source: National Experts Oct 2016)Figure 31: Schematic of the institutional frameworks related to reform of the drinking water and sanitation sector (DWSS)Figure 32: Rainwater harvesting storage for the Hamaleno impluvium with effective rainfall set to 0.5l/m2/d and soil holding capacity at 180 l/m2.Figure 33: Rainwater harvesting storage for the Trodjou impluvium with effective rainfall set to 0.5l/m2/d, soil holding capacity at 180 l/m2 and evapotranspiration 3.0.Figure 34: Rainwater harvesting storage for the Hamtroni impluvium with effective rainfall set to 0.5l/m2/d, soil holding capacity at 180 l/m2 and evapotranspiration 3.5.Figure 35: Rainwater harvesting storage for the Manvangani impluvium with effective rainfall set to 0.5l/m2/d, soil holding capacity at 180 l/m2 and evapotranspiration 3.0.Figure 36: Rainwater harvesting storage for the Hamaleno impluvium with effective rainfall set to 0.7l/m2/d, soil holding capacity at 250 l/m2 and evapotranspiration 3.5.Figure 37: Project organisation structure organogram 124

TABLES

Table 1: Comoros sustainable water resources and their exploration23

Table 2: Method of water supply, from the 2003 general census of the populationTable 3: Summary table of input and output parameters used to investigate rainwater harvesting vulnerability

Table 4: Summary table of input and output parameters used to establish rainwater harvesting storage, person demand 30 lpd, storage capacity 47 m3 .Table 5: Summary table of input and output parameters used to establish rainwater harvesting storage, person demand 25 lpd, storage capacity 47m3 .Table 6: Summary table of input and output parameters used to establish rainwater harvesting storage, person demand 20 lpd, storage capacity 47m3 .Table 7: Summary table of input and output parameters used to establish rainwater harvesting storage, person demand 15 lpd, storage capacity 47m3 .Table 8: Estimated groundwater resources for each island.Table 9: Table of Production Borehole Properties .Table 10: Table of water resource exploitation.Table 11: Table of selection criteria used for targeting villages.Table 12: Prioritization of the options from consultations, per island, and at the national level.Table 13: Table of concrete activity after the ACCE project.Table 14: Table of water balance for Grand Comore

5

Table 15: Boreholes in in the vicinity of the new Hambou Djoumoipanga well (Zone 3)Table 16: Table of stream flow data for Mutsamudu and Daji. 100Table 17: Table of catchment characteristics from GIS data. 101Table 18: Dry Season Flow Estimation Input Parameters 101Table 19: Stream flow estimates for Anjouan and Moheli 102Table 20: Table of Low (base) flow estimates for Anjouan and Moheli 102Table 21: Table of the minimum flows during the driest months 103Table 22: Table of minimum stream flow estimates versus water demand for Zones 7-15 103Table 23: Table of stakeholders 125

PLATES

Plate 1: Photo of the Sangani impluvium.Plate 2: Photograph of TP5 excavated using concrete caissonsPlate 3: Photograph of coastal plain containing the freshwater water supply wells for Moroni (capital visible in distance) – note craters adjacent to coastline.Plate 4: Photograph of water well ON39.Plate 5: Photograph of a hand dug well in floodplain alluvium near Pomoni

MAPS

Map 1: Geological map of Grande Comoros and location of boreholes.

APPENDICES

APPENDIX 1: Natural characteristics and land use maps

APPENDIX 2: Natural hazards, vulnerability and risk zone maps

APPENDIX 3: Analysis of dry days and rainfall intensities

APPENDIX 4: Schematics of existing and proposed water supply infrastructure

APPENDIX 5: Crop water requirements

APPENDIX 6: Consultation, meeting and engagement documents

APPENDIX 7: Selection of intervention zones

APPENDIX 8: Selected zones of intervention

APPENDIX 9: Intervention sites and land cover maps

APPENDIX 10: Locations and existing and proposed infrastructure

APPENDIX 11: Selected Photographs of Sites Infrastructure and Watersheds

6

APPENDIX 12: Detailed Water Supply Infrastructure Types

APPENDIX 13: Gender assessment and action plan

7

LIST OF ACRONYMS

AOI Areas of Interest

CCA Climate Change Adaptation

CSO Civil Society Organization

DRM / DRR Disaster Risk Management / Disaster Risk Reduction

EWS Early Warning System

GCF Green Climate Fund

GEF Global Environment Facility

GoC Government of Comoros

GW Groundwater

FS Feasibility Study

IWRM Integrated Water Resources Management

LDCF Least Developed Country Fund

MRV Monitoring, Reporting and Verification

NAP National Adaptation Plan

NAPA National Adaptation Programme of Action

NAMA Nationally Appropriate Mitigation Action

NGO Non-Governmental Organization

NRM Natural Resource Management

RWH Rainwater Harvesting

SDG Sustainable Development Goal

SME Small Medium Enterprises

SCA2D Strategy for Accelerated Growth and Sustainable Development

UNDP United Nations Development Programme

UNEP United Nations Environment Programme

WUA Water User Association

8

EXECUTIVE SUMMARY

This feasibility study assesses the vulnerability of the Comoros archipelago to climate change, specifically to enhanced rainfall variability and the impact this has on the nations drinking and irrigation water supplies. The study identifies climate change adaptation solutions to strengthen the resilience of drinking and irrigation water supply for this African small island developing state and least developed country to climate change risks.

Comoros has a very small national land area of only 2,612 km2 consisting of steep volcanic terrain, with no land further than 7km from the coast. It therefore has very small watersheds and aquifers which have little natural water storage capacity, and consequently are highly vulnerable to climate change magnified rainfall variability - as is the rural population reliant on only rainwater harvesting - resulting in predicted increases in water scarcity due to drought, flood and salinization impacts on the nations’ water supplies. Global Climate Models predict increases in drought duration of up to 48 days, increases in wet season rainfall of up to 45%, increases in storm event rainfall of 34%, resulting in at least equivalent increases in storm flows, and increasing watershed erosion not only by 2 orders of magnitude but permanently destabilizing the catchments.

The project will contribute to achieving three Fund Level Impacts, namely: i) increased resilience and enhanced livelihoods of the most vulnerable people, communities and regions; ii) increased resilience of health and wellbeing, and food and water security; and iii) improved resilience of ecosystems and ecosystem services.

The project’s climate change resilience impact focuses on rural and peri-urban communities in a vulnerable small island state, using an integrated, holistic approach to strengthening their access to reliable and safe water supply during periods of extreme climate variability.

To address this goal, the project will improve the resilience of existing water supplies in 15 target zones to climate change magnified drought, flood and erosion risks whilst increasing the capacities of state, non-state, peri-urban and rural institutions to plan, prepare, manage, monitor and protect water supply infrastructure, water resources and watersheds from these climate-related risks across the country and beyond the project duration.

To increase the quantity and quality of surface water and groundwater sources for urban, peri-urban and rural populations to both increasingly extreme dry and intense storm conditions, a mix of water capture, infiltration and storage mechanisms will be used. Specific climate change adaptation and risk reduction designs and management protocols are aligned with IPCC climate change predictions and will be further aligned to seasonal and event specific rainfall forecasts in order to sustainably manage increasingly variable water resources, including extended dry periods and intense rainfall events.

A social and economic feasibility analysis on climate proofing the water supply and a vulnerable site selection analysis were also conducted between September and November 2016 in which water demands up to 2043 were verified in each region and municipality. These studies act as the basis for recommending the proposed activities and budget.

10

A detailed water resources assessment was also undertaken in Mar-May 2017 to confirm the availability of specific water resources types and confirm the validity of the climate adaptation options supported by the project.

As the basis for a GCF Full Proposal, the FS defines clear outputs and activities that will directly address financial, technical, and institutional barriers preventing climate resilient water security in Comoros.

The following Feasibility Study identifies the recommended adaptation measures that should to be taken to build capacities on the national, island and local level to ensure climate-resilient water supply in alignment with the Comoros Sustainable Development Plan, SCA2D (2015-2019), the Comoros’ NAPA (2006) and its INDC to the UNFCCC (2015).

1. CLIMATE RISK PROFILE OF THE COMOROS

4.1 Country background

4.1.1 Introduction

Comoros is made up of three islands: Grande Comore, Anjouan and Mohéli (see Appendix 1 - Natural characteristics and land use maps). Classified among the Least Developed Countries (LDCs), Comoros is one of the poorest countries in the world, with a gross national income per capita of US$ 840 and an annual GDP growth of 3.5% in 2013, dropping to 1% in 2015.1 Furthermore, the Comoros has high levels of poverty (42.4%) and a chronic economic deficit, and is considered a highly indebted poor country.2

Comoros is also classified by the United Nations as a Small Island Developing State (SIDS), a group of countries with unique vulnerabilities in meeting sustainable development goals, and with particular exposure to climate change risks due to a combination of small land masses, fragile water resources, small populations and economies, isolation from global markets and resources, and the additionality of non-climatic hazard exposure, including volcanic and seismic events3.

4.1.2 Population

Based on data from the last national census carried out in 2003, the Comorian population was estimated at 794,678 inhabitants in 2016. The population density is among the highest in Africa, with approximately 3954 people per km2 in 2013 and population growth rate 1.71 % estimated in 2016.4 With almost 60% of the population under the age of 25 and median age less than 20, the Comorian population is very young (ranked 196 out of 229), with an associated limited national skill base. By 2033, the population is expected to reach approximately 1,151,320 inhabitants.5 Despite increasing urbanization (27.9% in 2003 vs. 31.5% in 2008), the rural population is projected to continue to exceed the urban population in 2030 (55%).6 In 2012, households

1 http://www.worldbank.org/en/country/comoros/overview

2 National Progress Report on MGGs (2012)

3 United Nations Res/69/15. SIDS Accelerated Modalities of Action (SAMOA) Pathway

4 http://www.tradingeconomics.com/

5 https://www.cia.gov/library/publications/the-world-factbook/geos/cn.html

6 African Development Bank, Strategy and Programme of PEAPA in the Comoros: Socio-economic context11

averaged 5.9 members. The Comoros is on the UN list of least developed countries, and poverty is widespread, with 42.4% of the population living below the national poverty line in 2014.7

4.1.3 Current political structure

The Comoros is known to have a long history of political and institutional instability, having had 20 coups or coup attempts since declaring independence from France in July 1975. In 1997, a political crisis erupted in Anjouan and Moheli, during which both islands claimed their independence and the return of French rule.. Following this, a new Constitution was adopted in December 2001, establishing the Union of the Comoros and granting considerable autonomy to each of the three islands. At present, the political situation can be described as a ‘federal presidential republic’, whereby the President of the Comoros acts as: i) the head of the government; ii) the head of state; and iii) the head of the multi-party system.

Although the adoption of this 2001 Constitution put an end to the 1997 political crisis, much remains to be done in agreeing on how to divide responsibilities and mandates on laws and policies between the union government and the island governments.

Furthermore, governance capacity is low as a result of repeated cycles of political crisis and instability. Institutional memory within government is also low because of the many changes in staff following changes in government. This fragmentation applies to the water sector, as it does to most branches of government.

4.1.4 Economic setting

After economic growth picked up to an average 3% from 2011 to 2013, a national electricity crisis stunted growth, which dropped to 0.6% in 2014 and 1% in 2015. Thanks to financial support to its energy sector by the Kingdom of Saudi Arabia8, growth forecasts for 2016 and 2017 are 4.1%.9 The Comorian economy is largely an inward-looking and poorly diversified subsistence economy, with 34.5% of GDP generated in the agriculture sector, 54.4% in the tertiary sector, and the secondary sector accounting for 12% (2014).

The economy depends highly on imports and, while there is potential to expand fishing and tourism, two economic sectors with high added value, current value addition by the economy remains weak. 10 Agricultural production generates 98% of export revenue, mainly through the production of vanilla, ylang ylang and cloves. Seventy-five percent of these exports pay for the food imported into the country.11

4.1.5 Livelihoods

Between 70-80% of the Comorian population are small-scale farmers that are dependent on rain-fed water resources for subsistence agriculture. Currently, national agricultural production meets only 40% of food needs in the country.

7 http://www.worldbank.org/en/country/comoros/overview

8 http://www.itfc-idb.org/en/content/itfc-partners-comoros-supporting-its-energy-sector

9 Perspectives économiques en Afrique 2016, VILLES DURABLESET TRANSFORMATION STRUCTURELLE, Banque africaine de développement, Organisation de coopération et de développement économiques, Programme des Nations Unies pour le développement (2016)

10 AFRICAN DEVELOPMENT BANK GROUP UNION OF THE COMOROS COUNTRY STRATEGY PAPER 2016-2020

11 UNEP Project Document : Building Climate Resilience through Rehabilitated Watersheds, Forests and Adaptive Livelihoods, PMS 5694

12

According to Comoros’ Country Work Programme (2015-2019), poverty issues and limited employment opportunities are severely hindering the country from have self-sustaining economic growth.

Most arable land is already being used for agricultural purposes (see Appendix 1 - Natural characteristics and land use maps), and often under unsustainable exploitation systems (e.g. poor agricultural practices, including absence of crop rotation or slash-and burn12, have reduced fertility and consequently reduced agricultural productivity). Furthermore, poverty is endemic among small-scale farmers, with an incidence of poverty ranging from 35% in Grande Comore to 60% in Mohéli and 64% in Anjouan.13

4.1.6 Water resources

Annual mean rainfall is over 1,000 mm on the three islands with maximum-recorded rainfall of 5,888 mm in Grande Comore, and over 3,000 mm in Anjouan and Moheli. However, rainfall varies considerably from one island to another and from one region to another within each island. The principal sources of water in the Comoros are rainwater collected in cisterns, river water and coastal aquifers.

The natural drainage systems on each island depend on their geological age and soil composition. Whereas Anjouan and Moheli have permanent surface water bodies (rivers on Anjouan, rivers and lakes on Moheli), Grande Comore does not, as up to 95% of precipitation infiltrates into the soil due to its high permeability.

All three islands have underground aquifers, but these have not been extensively studied, with the exception of Grande Comore where part of the aquifer is exploited.14

Previous assessments15 estimate the country’s sustainable annual water resources and their exploitation as follows:

IslandTotal Renewable Resources m3/yr

Renewable Surface Water m3/yr

Renewable Groundwater Resources m3/yr

% Surface Water Exploited

% Groundwater Exploited

Grand Comore 1 254 066 200

124 148 250 (10%)

1 129 917 950 (90%) 1.9 0.5

Anjouan 513 830 200213 928 000 (42%)

299 902 200 (58%) 2.3 0.6

Mohéli 117 236 40078 496 000 (67%)

38 740 400 (33%) 1.2 0.5

Table 1: Comoros sustainable water resources and their exploration23

12 Initial National Communication, 2002.

13 Rapport National sur le Développement Humain-Insécurité alimentaire et vulnérabilité, 2003-2004 (Union des Comores/ SICIAV/FAO/UNDP, page 29).

14 UNEP, 2002, “Atlas des ressources côtières”

15 AEPA Project 2013, Etudies Techniques, du Cadre Institutionnel Et Du Programme National D’AEPA.13

This suggests annually there is abundant replenishment of the nation’s water resources and that only a small percentage of this is currently being used. However such an assumption does not consider the unique geography of small island developing states.

The islands are small in size, Grand Comore is 1035 km2, Anjouan 440km2 and Moheli 220km2, but the furthest point from the coast is no more than 10km, 7km and 3km respectively, whilst the maximum ground elevations are >2,000m, 1,500m and >800m respectively (see Appendix 2 - Natural hazards, vulnerability and risk zone maps). The islands watersheds are therefore both steep and small, have limited area – typically <4km 2 on Anjouan and <2km2 on Moheli, whilst on all islands but on Grand Comore in particular, the steep terrain limits groundwater well and borehole drilling (due to high ground elevations and therefore the necessity for deep drilling to reach the water table) to within 2-3km of the coast and therefore results in borehole abstraction being close to the coastal strip of saline intrusion23.

Streams are therefore susceptible to both dry periods, when flows become minimal and can dry up altogether, but also storm rainfall, causing soil erosion, clogging and damaging intakes and delivering highly turbid and therefore untreatable water, whilst most of the total stream flows are lost to the coast.

The majority of the boreholes (31 of 50) on Grand Comore pump brackish groundwater into the reticulated supply system.

Therefore despite relatively abundant annual rainfall, the supply of adequate safe drinking water within the last decade has become increasing problematic during the dry seasons and after storm events, to meet the needs of the Comorian population. Average water demand is estimated to be 35 litres per person per day, with that in Moroni closer to 50 lpd. Only ten of the forty rivers on Anjouan and Moheli flow all year round, with most reportedly dry or in the process of drying up in the dry season.

Figure 1: Map of Year Round River Flow in Anjouan

14

The available water resources on each island are discussed in more detail in Section 1.4 to 1.6 below.

4.1.7 Access to water

There are differences between the islands in terms of water supply methods. In Anjouan, running water at home is the most widespread with 44% of households providing water to 63% of the population ( i.e. households and neighbours).

Island

WATER SUPPLY METHODRunning water at household

Running water at neighbor’s house

Private cistern

Public fountain

Public cistern

Boreholes / Shallow wells

River Intake

Moheli 33.9% 22.4% 0.8% 23.6% 0.6% 11.7% 7.0%Anjouan 44.4% 19.2% 0.4% 30.3% 1.6% 0.2% 3.9%Grande Comore 14.7% 6.0% 54.8% 18.2% 4.7% 1.5% 0.2%

Average 29.6% 13.1% 26.4% 24.1% 3.0% 1.5% 2.3%

Table 2: Method of water supply, from the 2003 general census of the population16

Similarly, in Mohéli, running water at home is the most frequent source of water covering 34% of users (56% including supplies to neighbours). These household connections as well as public fountains (village standpipes) and cisterns (village storage tanks) provide 94% and 80% respectively of the domestic water supply in these two islands and are all supplied by stream intakes. This rises to 98% and 87% when private river intakes are included.

However, in Grande Comore, 55% of users have private rainwater tanks, the 21 % of household running water and 18% of public fountains (i.e. 39%) being fed by pumped groundwater wells and boreholes.

The lack of effective water demand management (unaccounted for water has been estimated to be up to 50%) puts the Comoroian population at risk when water resources availability reduces during the dry seasons.17

On average, water consumption in the villages per capita is 35 litres per day,18 which falls short of the recommended consumption of 50 litres per capita per day.19

4.1.8 Water quality and public health impact

The majority of water destined for domestic use in the Comoros is not treated. 20 Poor water quality has a direct impact on public health. During periods of strong rainfall, high turbidity levels have been shown to

16 Recensement général de la population et de l'habitat, 2003

17 Rapport sur la vulnérabilité et l’adaptation sur les ressources en eau face aux changements climatiques sur l’île d’Anjouan

18 Socio-economic Assessment Oct 2016

19 Peter Gleick “The Human Right to Water”, Water Policy, Elsevier Science (1999) pp. 487-503.

20 African Development Bank, Strategy and Programme of PEAPA in the Comoros: Socio-economic context15

cause rhexistasia. Water sources are also impacted by bacterial contamination from pathogens such as Salmonella and dysenteric amoeba.21 Water is distributed without any physio-chemical or disinfection treatment (only minimal chlorination in the region of Moroni). Consequently, typhoid fever and diarrhea are the leading sicknesses for children between 3 and 5 years. Their increasing evolution is show in the Figure below.

Figure 2: Cases of typhoid and diarrheal disease in Anjouan in 2010 and 201122

4.1.9 Water Supply Service Providers

The water supply service providers are currently unable to provide adequate levels of operation and maintenance to the existing water supply systems. This has been recognized by the national government as a priority with water sector wide reform initiated in 2015 with the development of national water reform legislation (see Section 2).

In the urban and peri-urban region of Grand Comore, only 34% of the water volume is metered. Water leakage from the supply network is therefore poorly defined, although estimates have been made as high as 50% on Grand Comore and Anjouan23.

These service levels are however entirely consistent with other Least Developed Country Small Island Developing States24 such as Kiribati, Tuvalu, Papua New Guinea and the Solomon Islands, which have reticulated water supply system leakage of 30-60% and provide as little as 5 lpd of drinking water. Indeed non- LDC Pacific SIDS such as the Marshall Islands and Nauru can only manage to provide up to 30 litres per person per day to their town populations.

The level of water supply provision in Comoros is entirely consistent with that achieved in other LDC SIDS and is therefore a realistic level of development at this time.


22 Données brutes du service statistique de la DRSA, 2012

23 Raphael Tshimanga, 2015. Mutusmudu Watershed Integrated Management Plan. UNEP IWRM SIDS Programme

24 http://www.pwwa.ws/index.php?page=Benchmarking2

16

4.1.10 Willingness to Pay

Populations pay by volume in the Moroni region whereas in Anjouan and Mohéli, the Union des Comités de d'eau à Anjouan/Mohéli charges a fixed tariff at 1,000 KMF per month for water that is not potable. 25 This was a similar rate set by AFD’s RESEAU pilot projects in the villages of Ongoni and Mjimandra. This project implemented individual connections but the consumption was limited to 10 m 3/household/month (i.e. approximately 35 lpd at US$ 0.2/m3).

In the dry season rurual villagers procure water from the twon water supplies. A container of 20 liters of non-potable water (not sterilized) costs 250 to 500 KMF (US$ 25-50/m 3) in Grande Comore against 25 KMF (US$ 2.5/m3) in Anjouan.

4.1.11 Existing Water Supply Shortages

Section 1.1.6 on Water Resources identifies the inherent vulnerability of SIDS to climate extremes due to the small fragile nature of their water resources and the lack of natural water storage to buffer against droughts and storm related floods and erosion.

Water supplies therefore already have to deal with these ‘extreme hydrological stress’ periods which force the water supply systems to operate at, near or beyond their intended design (or lack of designed) normal operating conditions.

Consequently local populations apply a variety of palliative adaptation strategies to cope with the periods of water shortage. These tend to be stand-alone adaptations that do not constitute a conscious response to climate-related stresses, but instead result from changes meant to satisfy the need for water under the current conditions (inclusive of on-going climate change impacts).

During the rainy season, families actively conduct primitive rainwater harvesting using garbage cans, jerrycans or by building cisterns and placing tanks under house roofs.

At times of severe drought, when irrigation is reportedly not possible for 60 days leaving the soil too dry to support agriculture, the Comorian populations mobilize vehicles to travel to the capitals or to neighboring communities to fill up as many jerrycans as possible from running water sources. 26 At these times, water is often distributed during only one period per day.27 Pipes are often tapped illegally to create pirated connections.

On the village level, water from ablutions, ylang ylang distillery cooling water and wash water are reused during dry seasons, although they are not re-used year-round.

In some villages on the island of Anjouan, re-use of water is a widespread and common practice.

● Soapy water from laundry or dishes is reused to water vegetable gardens and nurseries in some

households in Nioumakele. This practice is abandoned as soon as the rain arrives.


26 Based on Stakeholder discussions held in November 2016, the local definition of drought is when crops fail after 60 days of no rain during the rainy season.

27 DGEF, UNDP, GEF April 2012. Report on the Vulnerability and the Adaptation of Water Resources at Risk to Climate Change Impacts on Anjouan.

17

● Water used for the ablutions in the mosques is channelled to irrigate nearby nurseries and

(Nioumakele).

● Water used to cool ylang ylang vapor in distilleries is reused as hot laundry wash water.

At the worst of times, when water resources are extremely limited during the dry season, the same water points are used for livestock and human consumption.

These ‘indigenous’ household and community adaptation responses to periods of water shortage however have limited benefit and can only increase their resilience to a small extent. Periods of water shortage beyond that presently being experienced will expose these communities to conditions beyond which their ad hoc adaptation responses can cope with. An example of this is given under the Rainwater Harvesting section of the Water Resources Baseline Study (see Section 1.4).

With increasingly scarce water sources and extending dry seasons, these adaptation strategies are clearly not sustainable.

4.1.12 Economic implications

Comoros is one of only 6 countries to be classified as both a Least Developed Country and a Small Island Developing State. It is one of the poorest countries in the world, with an estimated 80% of the rural population considered poverty-stricken and 46% living in absolute poverty (<$1.25/person/day). In recent years, structural constraints (e.g. in the electricity sector) and slower-than-expected implementation of the public investment program have resulted in economic stagnation, which is particularly bad considering a population growth rate of 2.5%.

The budget of Comoros has been in significant deficit in recent years and will continue to be so at least until 2020 (last year of IMF projections). The budget deficit was 14.8% in 2016 and is expected to increase to 15.6% in 2017, settling at 11.5-12% in 2018-20. The economic slowdown in 2015/16 and related decrease in tax revenues accentuated deficits and lead to large arrears in the payment of public sector wages.

The average household water bill in Moroni is around US$4-5 per month, or approx. 8% of the average wage – a high percentage, especially for lower-income households.

4.1.13 Gender aspects

In the Comoros, women and girls are traditionally in charge of collecting water, and therefore are disproportionately affected by increasingly scarce water supplies. Due to increased rainfall patterns and temperatures, rivers are drying up and the freshwater yields of wells are diminishing. Consequently distances to safe water resources are predicted to increase in rural areas. Women and girls in the Comoros have to walk typically approximately 195 meters to the closest water source. To get the minimum amount of necessary daily water, women and girls walk this distance, back and forth, up to five times per day; which results in about 2 kilometers per day per household.28 Women spend an average of 2 hours per day collecting water.29

Water collection is increasingly demanding and represents an opportunity cost in terms of time and labor.

28 Stratégie et Programme d’AEPA aux Comores (2013): Contexte socio-économique de l’AEPA.

29 Socio-economic analysis conducted in 2016 for this Feasibility Study18

Moreover, the quality of the available water is often questionable. Poor water quality has led to increased health issues and disease, such as typhoid fever, diarrhea and various water-borne diseases.

Girls are disproportionately affected by climate change as compared to boys. Typically, when resources are limited and families have to choose which children to send to school, boys usually have priority. 30 When increased help is needed in the households (for example after climate shocks), girls rather than boys are held back from school to help out. In the Comoros, girls are traditionally involved in housework, particularly in doing laundry and collecting water. With increased scarcity of water, girls will have to spend more time collecting water, taking time away from school and other chores.

4.2 Climate Change in the Comoros: Risks and Impacts

Climate change is expected to adversely affect the Comoros with impacts such as i) changes in rainfall levels and patterns and the subsequent lengthening of the dry seasons and shortening of rainy seasons; ii) increased temperatures; iii) sea level rise (and subsequent salinization of critical coastal aquifers as a result of salt water intrusion); and iv) an increased frequency of climatic hazards (such as tropical cyclones, droughts, episodes of heavy rainfall and flooding). Sea level rise is predicted to increase by 4 mm per year for the next 50 years. 31

Water supply in particular is directly threatened by changing climatic regimes, namely increasing temperatures and evapotranspiration rates, decreasing precipitation reducing stream flows and rainwater harvesting and increasing groundwater salinity and increased storm rainfall intensity increasing erosion and turbidity therefore reducing water quality (NAPA, 2006; PRGS, 2009).

4.2.1 Baseline climate

The climate in the Comoros is typically that of a tropical oceanic country, characterized by two seasons: a warm and humid rainy season from November to April with average temperatures of 27°C, and a cool and dry season, from June to September, with average temperatures of 24°C. The country receives more than 85% of its precipitation during the rainy season, during which the spatiotemporal distribution of rainfall is highly heterogeneous across the islands, with average monthly precipitation values between 116 and 407 mm between 1971-2000. During the dry season, the average monthly precipitation is of 194 mm. The climate on the Comoros is characterised as having tropical humid and tropical arid mesoclimates. 32

Given its geographical location and climate conditions, Comoros is in the Indian Ocean Cyclone belt. It therefore routinely experiences tropical storms, cyclones, wind damage, landslides, storm surges and sea inundation, in addition to non-cyclone related droughts (see Appendix 2 - Natural hazards, vulnerability and risk zone maps).

4.2.2 Observed effects of climate change

As noted in the Comoros’ National Adaptation Programme of Action (NAPA) and UNFCCC National Communications, annual temperatures have increased by around 1oC over the past thirty years, with the duration of the rainy season decreasing from six months to two to three months. Studies conducted in

30 Stratégie et Programme d’AEPA aux Comores (2013): Contexte socio-économique de l’AEPA.


32 Seconde communication nationale sur les changements climatiques, 2012 19

Anjouan and Moheli during the first National Communication (2002)33 concluded that out of the 40 permanent river basins that used to exist in the 1950s, only 10 remain as perennial today. Many dry up in the dry season, leading to a reduction in water availability for drinking, irrigation and hydro-electricity production. Increasing aridity contributes to an agricultural water deficit that can last up to 6 months.

This has been accompanied by an increase in frequency of severe rainfall events and flooding. River flows have decreased, and the drying of rivers occurs earlier following the rainy season, attributed only in part to the degradation of watersheds.34

Historical observation has shown a trend towards the increase of extreme meteorological phenomena over the past thirty years.35 In addition to prolonged droughts, the three islands of the Comoros also suffer from intense flooding episodes during the rainy season. The recent floods of April 2012 were characterized by heavy rainfall, six times more intense than the norm for the season, flooding the towns, impacting agriculture and degrading forests and watersheds.36 Other observed effects of climate change include cyclones and tropical storms (see Appendix 2 - Natural hazards, vulnerability and risk zone maps).

Mayotte, the non-independent island of the Comoros archipelago and still a French department, only 70 km from Anjouan, was hit by a severe drought following the delayed onset of the rainy season in early 2017. The situation underscores the vulnerability of small island developing states to climate change induced alterations to rainfall patterns. In response to forecasts predicting a prolonged dry season in November, 2016, the island’s local authorities called on the population to ration water. Despite these efforts, the French minister of Overseas designated funds totalling 500,000 euros to schools on the island for the purchase of bottled waters and cisterns to guarantee students access to potable water. The option of delivering water via a tank ship to remedy the situation was also considered. 37

This feasibility study has also undertaken an assessment of the limited monthly and daily rainfall data made available to try to identify evidence of actual increasing climate change impacts on rainfall patterns in Comoros in the last 20+ years.

Long Term National Monthly and Annual Rainfall Analysis

An analysis of daily (2008-2016) and monthly (1901-2015) rainfall data for Moroni (south-west Grand Comore) and daily rainfall data for Ouani (north-east Anjouan) has been undertaken as part of this proposal process, to look at frequency of extreme dry periods and wet events and to explore trends in rainfall extremes. The monthly data lends itself to consideration of extended dry periods, the daily (but much shorter period) data at extreme wet events.

The monthly rainfall data record for Moroni when aggregated into 12 month totals and then ranked for the entire rainfall record shows the 4 driest 12 month periods in the last 60 years to have been the 12 months before Feb 1999, Nov 2003, Dec 2007 and Jan 2013 (see Figure 3).

33 Abdou, Soimadou, Étude de vulnérablité dans le secteur forestier, 2005.

34 See for example Watershed management field manual, T.C. Sheng, FAO, 1990.

35 http://unfccc.int/resource/docs/napa/com01e.pdf

36 Mansourou, A., 2013, Contribution à la gestion des risques de catastrophes naturelles: cas des inondations aux Comores, Université Senghor.

37 www.lemonde.fr/societe/article/2017/02/10/mayotte-touchee-par-une-penurie-d-eau-depuis-plus-de-deux-mois_5078001_3224.html

20

There is also a clear trend to more drying conditions generally throughout the annual moving mean since 1960. This confirms not only a general reduction in rainfall over the last 5-6 decades, but also an increasing frequency of the most extreme dry periods in the last 1-2- decades. It is reasonable to conclude therefore that Comoros is already starting to experience more extreme rainfall patterns and its current baseline therefore already consists of climate change accelerated climate variability.

Daily Rainfall Analysis

A 9 year daily rainfall data set has been secured for Moroni and Hahaya on Grand Comore and Ouani on Anjouan. This enables an assessment to be made on sub-monthly rainfall patterns.

Dry Day Analysis – see Appendix 3 - Analysis of dry days and rainfall intensities

A Dry Day analysis has been undertaken to identify the number and duration of dry day periods and explore whether these have increased over the last 9 years. The analysis shows that typically there are 212 dry days per year in Moroni, 247 in Hahaya and 243 in Ouani per year ( i.e. 58-67% of the year). The average longest consecutive dry day period was 20 days in Moroni, 45 days in Hahaya and 37 days in Ouani. These lengths of dry periods can therefore be expected to occur typically every year.

Figure 3: 12 month percentile rank of draught data from 1960 – 2015

The maximum consecutive dry day period in the last 9 years was 36 days in Moroni (well recognized as one of the wettest parts of the country), 155 days in Hahaya and 71 days in Ouani.

There is no obvious trend in the number of dry days or maximum run of consecutive dry days per year over the last 9 years. There is however an increasing trend in the number of 10 consecutive dry day periods within a year over the last 9 years.

21

The above analysis was repeated for Effective Dry Days – that is to say days when rainfall minus evapotranspiration are <0 mm/d – which is a more useful indicator for agriculture. In this analysis the longest consecutive effective dry period in Moroni increased to 54 days and in Ouani to 92 days, although that in Hahaya remained 156 days. The length of the maximum effective dry day period has an increasing trend for Ouani.

It should be noted, as stated earlier, that the 4 driest periods on record since 1960 have been observed in the last 16 years. As such these dry day periods are part of an increasing drying trend in the rainfall. Daily rainfall data was not made available pre-1998, but it is likely dry periods were less extreme before this date, based upon a review of the monthly data.

Storm Rainfall Analysis see Appendix 3 - Analysis of dry days and rainfall intensities

The daily rainfall data was also used to consider the frequency and intensity of extreme rainfall events. Again this is not an analysis that can be undertaken using monthly rainfall data, so the analysis is limited to the last 9 year period only.

Rainfall events can of course be over more than 1 day, with tropical storms and cyclones sometimes persisting for more than 2-3 days spread across 3-4 calendar days, or more. The daily analysis was therefore undertaken on not only for 1 day, but also aggregated for 2 day, 3 day, 4 day and 5 days, as well as for 10 and 15 days – the longer periods being of relevance to surface water resources .

The high rainfall analysis identified the maximum daily rainfall to be 423 mm in Moroni, 197mm in Hahaya and 347 mm in Ouani – all in different years. The Moroni rainfall occurred in April 2012 and was one of the days of intense rainfall that caused the April 2012 flooding, which caused much damage on all 3 islands, but was particularly extreme in southern Grand Comore, severely damaging the Moroni city water supply for almost 2 months.

The April 2012 rainfall event was actually 6 consecutive days of >100mm/d rainfall, totaling >1250mm of rainfall, more than the annual average amount in some parts of the country.

The daily high rainfall analysis shows that annual maximum daily rainfall is >100mm/d in 8 years of the last 9 years at all three stations. There are no obvious increasing trends over the last 9 years, however this is clearly a significant amount of water, especially when considered with the 3 day total for all 3 sites being > 200mm, highlighting there is a persistent and continuous risk of flash flood flows in Comoros.

4.2.3 Predicted climate change

Future climate change is likely to increase the frequency and severity of storms, exacerbate climate variability and accelerate sea-level rise.

Reported monthly precipitation and mean temperature measurements and projections under three different emissions scenarios (SRES B1; SRES A2; SRES A1B) demonstrate and predict a decline in the dry season rainfall of 2-14% by 2090. While projections of mean annual rainfall vary from one model to the next, ranging from -15% to +39%, seasonal projections show more accurate projections with decreases in rainfall from June to November and increases from December to April (see Figure 4 below). The mean annual temperature is

22

projected to increase 0.8 to 2.1oC by 2060, and 1.2 to 3.6oC by 2090, and a 20-cm rise in sea level is expected by 2050.38

Figure 45: Seasonal precipitation projections in the Comoros from 1960 to 2100 (UNEP) 39

Figure 56: Mean temperature anomaly annual in the Comoros from 1960 to 2100 (UNEP) 40

Black curves show the mean of observed data from 1960 to 2006, Brown curves show the median (solid line) and range (shading) of model simulations of recent climate across an ensemble of 15 models. Colored lines from 2006 onwards show the median (solid line) and range (shading) of the ensemble projections of climate under three emissions scenarios. Colored bars on the right-hand side of the projections summarize the range of mean 2090-2100 climates simulated by the 15 models for each emissions scenario.

A specific review of Global Climate Model predictions for Mutsamudu in Anjouan reports 41 a 5% reduction in annual rainfall to 2065, but more importantly up to an 80% reduction in dry season rainfall (June to October) is predicted and up to 100% increases in monthly rainfall for some GCM predictions in some wet season months.

GCM Predicted Rainfall Change Analysis

To assess the impact of future climate scenarios in Comoros, a climate change projections analysis has been carried out specifically for this Feasibility Study, using both observed (historical) climate data and a set of modelled climate indicators retrieved from the World Bank Climate Change Knowledge Portal (CCKP). These climate indicators were derived from the Coupled Model Intercomparison Project, phase 5 (CIMP 5; Taylor et al., 2012). The CIMP 5 is a globally coordinated multi-model dataset encompassing an ensemble of Global Climate Models (GCMs) and a previously agreed-upon suite of Representative Concentration Pathways (RCPs;

38 C. McSweeney, M. New and G. Lizcano, UNDP Climate Change Country Profiles Comoros,

39 Ibid.

40 Ibid.

41 Raphael Tshimanga, 2015. Mutusmudu Watershed Integrated Management Plan. UNEP IWRM SIDS Programme.23

Moss et al., 2010), which represent different possible future radiative forcing scenarios through a selected evolution of distinct emissions and land-use change. The CCKP-CIMP5 collection consists of 35 GCMs (World Bank, 2017).

The future emissions scenario used in this study is the RCP 8.5, which is consistent with 8.5 W/m2 of anthropogenic radiative forcing by 2100. This is widely considered the ‘business-as-usual’ scenario as it represents the trajectory that anthropogenic carbon emissions are presently tracking (Le Quéré et al., 2016). Climate model projections are available for 4 future 20-year climatological windows (2020-2039; 2040-2059; 2060-2079; 2080-2099), and presented as anomalies to the baseline period (1986-2005). The analysis presented in this assessment is focussed on the projected changes for the periods 2020-2039 and 2040-2059.

The climate baseline (i.e., reference period) for this study has been established based upon 2 sets of historical rainfall data: i) daily rainfall observations from 3 locations – Moroni, Hahaya (Grande Comore) and Ouani (Anjouan) – that are available for the period 2008-2016; and ii) monthly rainfall totals for the period 1986-2005, that have been retrieved from the World Bank CCKP.

For the purpose of project design, the GCM-projected changes for each climate indicator have been statistically summarised in 2 scenarios: i) the mean projected scenario; and ii) the 95% percentile projected scenario, i.e., the greatest projected reduction (or increase) within the 95% confidence limits.

Drought Projections

There are several ways to assess changes in drought, including, but not limited to, metrics such as drought frequency, single-event duration, or cumulative multi-event duration. In this assessment drought changes have been analysed in terms of the duration of the largest single-event drought per year (i.e., additional number of consecutive dry days during the drought event), assuming days with less than a minimum rainfall (threshold) to be dry days.

The drought analysis has been performed using 2 different daily rainfall thresholds of 1mm and 5mm. Since CCKP-CIMP5 model projections regarding additional number of cumulative dry days are based upon a threshold of 1mm, historical rainfall records have been used to establish the relationship between 1mm and 5mm-rainfall-threshold drought durations, to be able to infer projected changes in additional number of days with less than 5mm rainfall.

Using a daily-rainfall threshold of 1mm, the mean scenario projects that drought duration in Grande Comore will increase by up to 12% (2020-2039) and 24% (2040-2059), whereas the 95% percentile scenario projects increases in drought duration of up to 46% (2020-2039) and 89% (2040-2059). This is an additional consecutive dry day extension to the current drought length of up to 24 days.

However, these values further increase when raising the daily rainfall threshold to 5mm, which accounts to a higher degree for the increasing evaporative demand of the atmosphere in a warming climate. In this case, drought duration is projected to increase by up to 17% (2020-2039) and 34% (2040-2059) under the mean scenario, and as much as 62% (2020-2039) and 123% (2040-2059) under the 95% percentile scenario. This is an additional consecutive dry day extension to the current drought length of up to 48 days.

By comparison, the actual maximum consecutive dry days (<5mm/d) observed across the country in the last decade varied between 54 and 132 days at the 95%ile, depending on location.

24

Extreme rainfall projections

Projected changes in the frequency of occurrence and magnitude of extreme rainfall events have been assessed using a number of climate indicators and focussing on Ouani (Anjouan).

Results show that the number of days per year with >20mm and >50mm rainfall are likely to increase, but not very significantly. Mean model projections predict less than 1 additional day per year with either >20mm or >50mm rainfall; the 95% percentile scenario projects up to almost 4 additional days with >20mm rainfall per year (2020-2039), decreasing to less than 3 additional days by 2040-2059.

However, total rainfall amount from very wet days (i.e., annual sum of rainfall when the daily precipitation rate exceeds the local 95th percentile of daily precipitation intensity) is projected to increase to 1190mm (8% increase) and up to 1610mm (45% increase) under the mean and 95% percentile scenarios, respectively.

Because rainfall is then concentrated into water course flow pathss, and because the catchments in Comoros are so small and so steep, the percentage increase in peak flood flows – i.e. those flows most likely to be creating damage, is greater than the percentage increase in rainfall. So peak flood flows will increase at least by 45% but in reality considerably more.

These results show that rainfall during the wettest 5% of days will potentially increase by >500mm. In addition, changes in the largest single day and consecutive 5-day rainfall amounts are projected to increase by 1-3% under the mean scenario; nevertheless, the 95% percentile scenario suggests both indicators could increase up to 9% during the time period 2020-2069.

To conclude, frequency and magnitude of extreme rainfall events will increase; and, in particular, precipitation occurring during the wettest days (a proxy for rainfall intensity) is expected to rise very substantially by up to 45%. Peak storm flows are however expected to increase by an even higher percentage due to the rainfall being concentrated into flood flow corridors.

Erosion projections

The GCM results do not allow a direct assessment of erosion risk to be made from increases in rainfall. However, it is possible to use the GCM predictions of increases in rainfall to estimate erosion impacts of climate change.

The Revised Universal Soil Loss Equation (RUSLE; Renard et al., 1991) is an empirical erosion model recognised as a standard method to calculate the average risk of erosion on arable land. Using the RUSLE method along with historical monthly rainfall data, and rainfall variability model projections, projected relative changes in soil erosion that directly result from changes in the precipitation patterns have been estimated. To do so, the climate erosivity factor (R) of the RUSLE method, which accounts for the effect of intra-annual rainfall variability, has been used as a proxy to estimate soil erosion changes. It is important to note that any percentage change in the R factor will cause soil erosion to vary by the same percentage.

Mean-scenario results project that soil erosion will increase by 2.4% (2020-2039) and 3.3% (2040-2059); and up to 4.0% (2020-2039) and 5.1% (2040-2059) under the 95% percentile scenario, which is not insignificant.

However, the RUSLE analysis does only explore the direct relationship between soil erosion and increased monthly rainfall variability. In climates where storm events are typically 1 day duration, and perhaps up to 3-4

25

days maximum length, then the use of monthly rainfall will always under-estimate the significance of the short storm events to cause erosion.

Because of the ‘feedback’ process of erosion, once climate change enhanced peak flows increase erosion and start to de-stabilize the catchment surface, the climate change derogated watershed is then more vulnerable to erosion in not only later storm events but in subsequent non-storm flow events than it was before. Thus turbidity increases all year round due to the climate change enhanced flood flow initiation of erosion.

These observations are supported by research42 on watershed erosion rates that show a doubling of the rainfall intensity rate increases the erosion rate by an order of magnitude. The same research shows the erosion rate is an order of magnitude higher for poorly vegetated terrains compared to mature vegetation canopy. Therefore, storm damage to steep watersheds which removes mature vegetation canopy during the storm events not only can increase erosion rates rapidly by not one but two orders of magnitude, but then leaves the watershed more erodible, by an order of magnitude, to subsequent non-storm events.

Hence a 45% increase in rainfall intensity due to climate change has the potential to increase erosion within a catchment by almost 200 times because of the climate change initiation/acceleration of the erosion process.

Whilst the GCM predictions report rainfall intensity will increase during wetter months and the IPCC Indian Ocean Synthesis43 reports a probable increase in cyclonic activity, the GCMs do not specifically model the increase in cyclone activity. Therefore it is reasonable to assume that climate change will result in an ncrease in cyclonic storm events superimposed on already wetter wet seasons, with resulting further increases in rainfall intensity, peak flood flows, erosion and debris mobilization.

4.3 Overview of Vulnerabilities and impacts of climate change on the water sector

Climate change will have negative effects on the main socio-economic sectors of the Comoros and on the country’s infrastructure. This section describes the impacts that are likely to be faced by each sector under predicted climate change conditions.

The agricultural sector is expected to suffer losses in production under climate change. Acting in tandem, rising temperature and increasing rainfall intensity will accelerate the erosion of the fragile soil, decreasing agricultural production. Crop water demands will also increase due to rising temperatures. Crops cultivated in the open field system would be the most vulnerable to climate change, given the lack of vegetation and forest cover of such production systems. Mixed cropping systems (traditional agroforestry and cultivation under natural forest cover) would better resist climate change.

Water quantity and quality is expected to be impacted by changing rainfall patterns. Predicted decline in rainfall during the dry season is expected to affect water supply and quality, by reducing rainfall harvesting yields, rainfall runoff and rainfall recharge. Reduced recharge will decrease dry season river flow rates and dilution effects, likely resulting in increased organic and chemical pollutant concentrations. By lowering the groundwater table and reducing the dilution effect, reduced rainwater infiltration will cause groundwater

42 USGS 1984. Physical Basis And Potential Estimatiqn Techniques For Soil Erosion Parameters In The Precipitation-Runoff Modeling System.

43 Commission de L’Ocean Indien. 2012. Synthese des travaux du projet Acclimate26

supply quality to deteriorate. It will also reduce groundwater recharge and therefore will increase and accelerate saline intrusion into the coastal aquifers.

Conversely, more intense rainfall, including tropical cyclones, will lead to flooding, resulting in greater soil erosion) and higher sediment loads in rivers. In this way, water quality and recharge of water resources will be adversely affected unless watershed adaptation measures are put into place.

At present, acute drought and its ability to induce water shortages is ranked the top impact affecting the daily lives of the Comorian population (NAPA, 2006). This situation is likely to intensify as a result of climate change, further affecting water supply and reducing water quality.

More intense rainfall will also lead to more episodes of flooding, which will also cause increased soil erosion, thereby reducing drinking water quality. Flooding also has the potential to damage infrastructure (e.g. roads, buildings, water supply infrastructure and housing), increase the spread of water-related diseases, damage or destroy crops and incite landslides and rockfall.44

Higher temperatures will increase evapotranspiration rates, further impacting water quality. Coupled with the anticipated decline in rainfall, increased evapotranspiration rates will reduce water recharge into rivers, river flow and groundwater supply rate. Whilst this directly affects water supply, it will also result in a reduction in the dilution effect (in both rivers and uncovered cisterns), thereby reducing water quality.

Whilst there is little effective water quality treatment in Comoros, the population is currently able to consume the existing water quality within culturally acceptable health consequences, through a combination of natural resilience and household treatment options. An increasing turbidity, rising temperature and microbial loading will collectively reduce water quality to a point where current anatomical resistance and treatment techniques will no longer be adequate.

Both changes in rainfall and temperature patterns (such as the prolonged dry season) are affecting and will continue to affect the quantity distribution and quality of water resources available to end-users.

Multiple sectors will be impacted by a projected 20 cm sea level rise by 2050. Along the Comorian coastline, the possible 20 cm rise in sea level by 205045,46 would be likely to result in: i) increasing levels of salt water intrusion in coastal aquifers; ii) the destruction of 29% of roads and other infrastructure with a damage cost of approximately US$ 400 million (roughly twice the country’s GDP (2013)47 48; iii) a loss of 297 ha of cultivable land; iv) the displacement of at least 10% of the population (PRGS, 2009); and v) reduced functioning of coastal habitats such as coral reefs49. All of the above have knock-on effects.

44 NAPA, 2006.

45 NAPA, 2006.

46 Global mean SLR, one of the more certain outcomes of global warming, is projected to be approximately 9 - 88 cm between 1990 and 2100 (Intergovernmental Panel on Climate Change. 2001. Technical Summary. Pp 21-23. IN: Houghton, J., Ding, Y., Griggs, D., Noguer, M., Van Der Linden, P., Dai, X., Maskell, K., Johnson, C., eds. Climate Change 2001: The Scientific Basis. Published for the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom, and New York, NY, USA, 881 pp).

47 http://data.worldbank.org/country/comoros

48 NAPA, 2006

49 This is because such habitats rely on a “stable” coastal environment.27

Salt-water intrusion, for example, will reduce the already limited availability of potable water sources by reducing water quality. Furthermore, the reduction in cultivable land will increase pressure on limited land resources and is likely to aggravate deforestation rates, which will have additional impacts on water availability. At present, salt-water intrusion into portions of Grande Comore’s coastal aquifers have increased the salinity of 31 of the island’s 50 boreholes to exceed drinking water standards50.

1.1 Climate Change Risks and Impacts on Rainwater Harvesting

As has been highlighted in earlier sections, in Grande Comore, approximately 60% of households use private and/or public rainwater tanks. Use of direct rainwater harvesting in the other islands is reportedly minimal. An analysis of rainwater harvesting yields and availability is provided below and its limitations and causes discussed.

In addition to concerns over rainwater availability, all rain water harvesting in Grand Comore is additionally at risk from non-climatic hazards to water quality which are quite specific to the local environment. Specifically, all rainwater harvesting is at risk from volcanic ash fallout from the Mt Karthala volcano. Mt Karthala has erupted most recently in 2005, 2006 and 2007, and is considered one of the most active volcanoes in the world51. The ash falls in 2007 covered ¾ of the island of Grand Comore in ash to a depth of up to 10cm 52. Whilst some 10 years later, ash fall is not currently an issue for rainwater harvesting, it remains an on-going threat to rainwater harvesting, and therefore contributes to water security concerns over the use of this technology per se.

Rainwater harvesting is reportedly not practiced in any formalized planned approach in Anjouan or Moheli. There is reportedly no attempt to routinely use building roofs to catch rainfall run-off.

1.1.1 Household Rainwater Harvesting

Whilst estimates for Grand Comore are approximately 50% of the population island wide uses rainwater harvesting, this is reported to vary between 40 and 90% for individual villages 53. Individual houses have on average a household water tank of 47m3 being fed by an average roof area of 35m2, although tanks can be as small as 15m3 or as large as 150m3.

Whilst it logically follows that a full 47m3 tank will supply a household of 8 people using 35 lpd for >150 days without further rainfall, daily water balance calculations undertaken as part of this proposal feasibility study over the period 1998 to 2016 for which daily rainfall is available (9 years) show that average household tanks (47m3) will fail to meet dry season household demand54 unless households adapt to the dry conditions and reduce consumption to 20 litres per person per day (year round), or unless they have access to other water sources e.g. communal water tanks.

50 The standards of drinking water should not exceed 2.5g/l of TDS based on generally accepted standards (e.g. WHO, EU) but a concentration of 3g/l is still considered to be acceptable in the Comoros. The INC (2002) reports that the salt content of coastal aquifers in Grande Comore varies between 2 – 6 g/l, depending on the distance from the shoreline.

51 Bachery P et al 2016. Structure and Eruptive History of Karthala Volcano

52 Morin J et al 2016. Volcanic Risk and Crisis Management on Grand Comore Island

53 MP2L, 2015. Schema Directeur AEP Mbadjini Est

5428

Table 3: Summary table of input and output parameters used to investigate rainwater harvesting vulnerability

A detailed interpretation of the cause of rainwater harvesting failure is not due to a lack of tank storage – a 47m3 household tank in fact never becomes full – but is primarily because of the inadequate roof area catchment size supplying the tanks. Indeed the water balance analysis suggests average sized property household tanks rarely hold more than 15m3 of water and therefore will usually run dry in less than 50 days, assuming no leakage, evaporation or livestock/crop watering usage.

Figure 67: Rainwater harvesting storage, person demand 35 lpd, storage capacity 47m3

29

Table 4: Summary table of input and output parameters used to establish rainwater harvesting storage, person demand 30 lpd, storage capacity 47 m3 .

Table 5: Summary table of input and output parameters used to establish rainwater harvesting storage, person demand 25 lpd, storage capacity 47m3.

30

Figure 78: Rainwater harvesting storage, person demand 20 lpd, storage capacity 47 m3


31


Climate Change Adaptation Conclusions and Recommendations

This finding is important as it demonstrates that committing project resources to household rainwater tanks of >15m3 is of limited value, and that > 30m3 of negligible value. Furthermore given 50% of the Grand Comore population has access to other water resources and 50% already has access to rainwater tanks as described above, then without increasing their house roof size – which is not possible without rebuilding the houses themselves – there is little way to improve household rainwater harvesting to be more resilient to climate change enhanced drought periods other than i) ensuring all the roof is guttered and ii) household rationing is promoted as part of drought warnings.

Given the paucity of freshwater provided by household rainwater tanks during dry periods, it is unlikely roof area catchments are not already maximized to that realistically achievable and that people do not self-ration. That said these should both be included in public awareness raising campaigns, community resilience planning and drought warnings.

1.1.2 Communal Rainwater Harvesting

Community rainwater harvesting tanks are also reported to be used, typically 2-5 per village, averaging 100m 3

per tank, but varying between 35m3 and 235m3 per tank55. These are generally used either for routine communal activities (such as weekly religious gatherings) or as a communal water reserve for periods when household rainwater tanks have gone dry.

Clearly the communal water reserve available for supply depends on the extent to which the tank is full at the time of household tank failure, as well as dependent populace and per capita demand, and the contributing roof area feeding the tank. For the 3 communes in M’badjini Est where data exists, the communal tanks could only provide water supply for a maximum of a week (assuming 35 lpd), although this could be stretched to 3 weeks on minimum drinking water rations only (10-15 lpd).

55 MP2L, 2015. Schema Directeur AEP Mbadjini Est32

The communal tanks potentially therefore provide a useful emergency buffer, to be able to cope with the typical annual consecutive dry day period in Grand Comore of 15-20 days calculated for the household rainwater tanks over the last decade.

However the combined household and communal rainwater tanks are not capable of providing a sustained drought water supply such as that required to overcome the GCM predicted extended dry periods of an additional 24-48 days extend due to climate change.


It is clear from the analysis above that communal rainwater tanks currently provide an important auxiliary water reserve for those communities relying solely on rainwater during short and average dry periods (<20 days duration), however it is also clear that these community tanks will not be able to sustain communities through dry periods of greater duration (>20 days) due to climate change.

The additional incremental increase in dry periods (up to 48 days) due to climate change is therefore critical as it is likely to push rural water communities dependent on rainwater harvesting from being marginally drought resilient to not drought resilient at all.

Additional community tanks would clearly be of benefit if sufficient community buildings existed to provide rainwater collection catchments to feed the additional tanks. However the number of community buildings in the rural areas is extremely limited – typically the mosque and local school only – and these are already usually serving community tanks. The sole reliance on rainwater harvesting by these communities over millennia has resulted in them having extremely effective and efficient rainwater harvesting systems – with little opportunity for improvement.

There is therefore little to be gained by increasing communal tank storage in these villages unless communal buildings are known to exist and which are not being exploited for rainwater harvesting already – this situation is unlikely to exist given current levels of water scarcity (i.e. 35 lpd). Instead alternative drought water supplies will need to be provided to these communities to overcome the additional climate change extended droughts of up to a further 48 days duration – in Grand Comore the only option is groundwater.

1.1.3 Volcanic Rainwater Impluviums

Rainwater is also captured on Grand Comore using a uniquely Comorian technique of sealing volcanic cinder cones. These are referred to locally as an impluvium (a term more usually used to describe a sunken rainwater collection pond in an ancient Greek/Roman house atrium).

A partially functioning impluvium is located at Sangani on the mid-point of the island ridge, between the northern and southern volcanic massifs (see Appendix 4 - Schematics of existing and proposed water supply infrastructure – Zone 6). It is lined with concrete and is showing signs of vegetation ingress into the concrete liner and is reportedly leaking.

33

Plate 1: Photo of the Sangani impluvium.

The impluvium receives both direct rainfall and some run-off from surrounding higher ground. The Sangani impluvium has an area of approximately 3,600m2 and an additional contributing surface catchment of approximately 8,500m2 giving a total catchment area of 12,100m2. It has a depth of 14m and an estimated volume of almost 17,000m3.

The impluvium can therefore hold the equivalent of 1400mm of rainfall (equivalent to the long term average annual rainfall for Hahaya) before it over-tops.

The impluvium is used for irrigation and other non-potable water uses only and is not used for potable supply except in extreme dry periods.

The stored water is open to the atmosphere and therefore likely to contain both some turbidity and detritus from surface water run-off but also microbial and macro-fauna, including parasites. It is currently unclear whether the water is used for non-potable uses in the village.

The irrigation scheme is currently understood to be in poor condition and leaks, although no estimates have been made of this inefficiency. Secured drawings suggest an irrigation area of approximately 10-14 hectares rely on the impluvium for dry season irrigation. During the wet season, crops receive direct rain fed irrigation only.

34

A daily water balance has been developed for the Sangani Impluvium using available daily rainfall data (2008-2016). The rainfall for Moroni has been used as its annual average is similar to that experienced at Sangani (2500mm/yr).

In developing the water balance, parameters are required not just for the inflows to the impluvium (rainfall, catchment area, run-off co-efficient) but also the irrigation water demand (crop area, crop type, direct rainfall, soil moisture balance (root constant, wilting point, maximum soil retention) as well as timing of crop planting and harvesting and direct rainfall received by the crop). This is a considerable data set.

Irrigation water demand was calculated using FAO software (CROPWAT) for different cash crops (tomatoes, bananas, potatoes, peppers and other vegetables) planted at different periods – see Appendix 5 – Crop water requirements. This resulted in a range of dry season irrigation demands depending on antecedent rainfall conditions and therefore soil moisture deficit, of up to 3.5 litres per m2 per day.

A daily spreadsheet water balance was then developed including options of including village non-potable water supply (up to 20 lpd, assuming 15 lpd needs to be potable), and using CROPWAT sourced estimates for soil water holding capacity, and expert judgement on direct rainfall capture by the soil during wet days (assumed to be 50%).

The resulting water balance for the Sangani Impluvium was estimated. Storage hydrographs are shown below for irrigation demands (ETc) of 2.5, 3.0 and 3.5 litres/m2/d, with 20 lpd non-potable water supply to the local village.

The storage hydrograph show both the benefit the impluvium makes to dry season irrigation (as demonstrated by the residual water storage volume in the impluvium), and the sensitivity of the calculations to the irrigation demand for the 14 hectares of irrigated crop, with an irrigation demand of 2.5 l/m 2/d being achievable through every dry season, 3.0 l/m2/d achievable through most dry seasons, and 3.5 l/m2/d unachievable for most dry seasons in the last 9 years.

It should be remembered that 4 of the driest years in the last 60 years have occurred during the last 2 decades. It has already been demonstrated (see Section 1.3) that these dry years are already being affected by the rainfall variability and dry season rainfall reductionimpacts of climate change. The GCM analysis (Section 1.3) predicts a further lengthening of the drought periods beyond the last decade of up to 48 days. The current maximum consecutive dry period for Moroni is 54 days (at the 95%ile), almost a doubling of the current experienced drought period in Moroni. The use of impluviums will evidently extend the ability to irrigate crops through the current dry seasons and half of the further climate change aridity.

35

Figure 89: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 2.5 l/m2/d

Figure 910: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.0 l/m2/d

36

Figure 1011: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.5l/m2/d

Further sensitivity analysis on the spreadsheet parameters allows consideration of the irrigation demand dependent on percentage of direct rainfall actually captured by the crop and soil, as well as the evaporation from the soil and downward leakage from the soil to the underlying volcanic aquifer.

The hydrographs below show the benefit (as measured by reduced irrigation water demand and increased water volume retained in the impluvum) of increasing intercepted direct rainfall from 50% to 75%, increasing the soil moisture store from 180 to 250 litres/m2 and then combining these two changes, all for the maximum irrigation demand of 3.5 l/m2/d.

37

Figure 1112: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.5l/m2/d and the captured rainfall at 70%.

Figure 1213: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.5l/m2/d and the soil holding capacity at 250 l/m2.

38

Figure 1314: Rainwater harvesting storage for the Sangani impluvium with evapotranspiration set to 3.5l/m2/d, rainfall captured at 70% and the soil holding capacity at 250 l/m2.


The impluvium irrigation analysis confirms impluviums can provide dry season irrigation of cash crops, although the reliability of dry season water supply will clearly depend on the contributing impluvium catchment area, its volume as well as the irrigation area.

Additional volcanic cones should therefore be identified for potential conversion to impluviums in this central agricultural zone of Grand Comore.

Clearly maximizing the impluvium storage surface area, its volume and contributing run-off catchment draining into the impluvium, as well as encouraging run-off from the catchment into the impluvium, are important design parameters and these should be used to select the various volcanic cones for conversion.

However being too ambitious with the irrigation area sizes to be supplied by the additional impluviums, will increase water demand and could result in mal-adaptation i.e. increasing water and food insecurity.

Further sensitivity analysis on the spreadsheet parameters allows additional adaptation options to be identified, including: increasing direct rainfall capture percentage by the crop - such as by planting crops within mini-bowl depressions to encourage rainfall to move toward each crop root; mulching around crops to reduce evaporation and increase soil water retention; and reducing leakage to the sub-soil and deeper

39

volcanic rock by reducing the below sub-soil permeability by compaction and/or placement of a clay pan horizon.

These latter options are all best described as agricultural/farming water use efficiency adaptation approaches and are critical to developing rural community adaptation resilience capacity through behavioral change informed by climate forecasting.

1.2 Climate Change Risk and Impacts on Groundwater Resources

The Comoros archipelago is constructed geologically from volcanic extrusive rocks. The youngest island geologically is Grand Comore dating as far back to 10 Million years ago, with Anjouan and Moheli dating back to 20 Million years. Grand Comore is evidently still volcanically active with eruptions as recent as 200756.

The islands therefore consist predominately of historic lava flows, laid upon each other. The older islands have been subject to much greater weathering, with geological logs showing thicknesses of up to 20m of weathered clays overlying the unweathered basaltic rock.

Generally lavas are considered to have good aquifer /groundwater potential, although they can be quite heterogeneous and have weathered clayey low permeability layers vertically in between the lava sequences.

Rapidly flowing lavas can result in lava tubes developing – essentially open conduits – which allow both the rapid transmission of groundwater through them but also the rapid intrusion of seawater into them when over-pumped.

Mt Karthala has shown evidence of changing from fast flowing basalt lavas which it has released every 6-8 years over the last 100 years (until 1991) to more violent Strombolian explosive eruptions. Field evidence suggests the most recent lavas have an ‘aa-aa’ texture, which is blocky and highly permeable, whilst more deeply buried lavas have ‘pa-hoe-hoe’ texture including the potential for lava tubes to exist. No less than 32 lava tubes were reported to be encountered during the construction of the 3km long international airport runway apron at Hahaya57.

There are different conceptual models for groundwater occurrence in extrusive volcanic terrains, including the Hawaiian – where the central island zone is dammed by vertical low permeability dykes resulting in high level springs – and the Canarian – where groundwaters perch on underlying low permeability horizons with the lava sheets rising with distance from the sea. But both models allow for basal groundwater bodies which are in hydraulic connection with the sea and at risk of saline intrusion when over-exploited, with perched higher elevation springs at greater altitude. There is insufficient data to be able to confirm which exists in Comoros.

56 Bachery P et al 2016. Structure and Eruptive History of Karthala Volcano

57 Morin J et al 2016. Volcanic Risk and Crisis Management on Grand Comore Island

40

Figure 1415: Schematic of conceptual models of Hawaiian and Canarian type volcanic craters and their related ground water occurrence.

Groundwater is known to be exploited extensively on Grand Comore (more than 50 wells/boreholes have been drilled and 5-6 high level springs exploited), to a much lesser extent on Anjouan and rarely on Moheli (7 wells on the Plateau de Djandro).58

It is important to recognize however that groundwater resources also provide the majority of the dry season baseflow into the streams and therefore whilst it may not necessarily be widely exploited directly via wells and boreholes beyond Grand Comore, it is a vitally important resource to sustaining dry season stream flows and high elevation springs.

58 Strategie et programme National d’AEPA des Comores

41

Based upon island scale water balances, groundwater resources for each island have been estimated 110 at:


Renewable Groundwater Resources m3/yr

Groundwater Exploited m3/yr

% Groundwater Exploited

Grand Comore

1 254 066 2001 129 917 950 (90%)

3,955,815 (Wells/Boreholes) 7,665 (Springs)

0.5

Anjouan

513 830 200299 902 200 (58%)

1,742,577 0.6

Mohéli 117 236 40038 740 400 (33%)

180,000 0.5

Table 8: Estimated groundwater resources for each island.

1.2.1 Groundwater on Grand Comore

On Grande Comore, in contrast to the other 2 islands, there is an almost complete absence of surface water. Water supplies have to be sourced therefore from groundwater resources and through rainwater harvesting.59

Due to the young geological age of Grand Comore (2 Million years), the island does not possess a surface water network. However, its geology, which consists of several alternations of fractured basalt, is highly permeable, and most of the rainfall (60%) infiltrates the soil to feed the groundwater reservoirs.

These natural water reservoirs have been exploited since the 1980s using 50 boreholes that were implemented at several locations along the coast by UN agencies and managed by the MAMWE to supply the island (see Figure 16). Because of the island’s steep slopes, all wells are located in the vicinity of the coast, as wells further inland would have to be constructed much deeper and would thus wells were either impractical to excavate or boreholes beyond the capacity of the drilling rigs on the island at the time. 60 Consequently, with the exception of 5-6 high level springs, all wells & boreholes on Grand Comore exploit the basal groundwater aquifer and are located within 3km of the coast.

59 The majority of population on Grande Comore lives upland and have poor access to water resources. Furthermore, they suffer ill-health as a result of poor water quality.

60 Jean-Christophe Comte et. al, Challenges in groundwater resource management in coastal aquifers of East Africa: Investigations and lessons learnt in the Comoros Islands, Kenya and Tanzania, Journal of Hydrology: Regional Studies 5, pp. 179–199 (2016)

42

Figure 1516: Location of boreholes that were implemented by UN agencies and managed by the MAMWE Error! Bookmark not

defined. 108

The salinity of the groundwater varies significantly from one well to another. While the Mdabjini massif that forms the SE tip of the island generally has low salinity (<2g/l) and hosts perched aquifers, the La Grille massif to the north and the central Karthala massif have salinities that are generally above 2g/l, except on the western flank of the Karthala massif that receives abundant rainfall. Ordinarily such waters would be considered to be non-potable but in Comoros they are used for washing and blended with rainwater for cooking.

43

Figure 1617: Map of geology and hydrogeology of Grande ComoreError! Bookmark not defined.109

Of the almost 50 wells and production boreholes drilled on Grand Comore, only 10 have salinities less than 1000mg/l. These include TP1, TP5 and ONU 4, 35 and 37 all immediately south of Moroni. Other moderately fresh boreholes can be identified mostly in the south-east and north of the island. These tend to be those at greatest distance from the coast. There is evidently a strong correlation between the area of greatest rainfall (in the south-west of the island) and the freshest groundwater.

Saltwater intrusion is mainly controlled by the amount of rainfall and distance to the sea. Salinity fluctuations are mainly controlled by the rising and falling tide, and longer term fluctuations in salinity between the dry and rainy seasons. Long term reductions in annual rainfall of 15% due to climate change as predicted by the GCM models, will reduce groundwater recharge by at least 15% but probably more due to parallel increases in temperature related evaporation, and increase groundwater salinity further.

Well and Borehole Yield and Salinity

The other factor that controls the salinity of the pumped groundwater is the borehole construction, specifically their depth, their diameter and the pumping regime. Pumping failures, i.e. pumping too much groundwater, results in the lowering of the groundwater elevation, which can lead to a sharp increase in salinity.61 This is referred to as Saline Up-Coning and can occur in boreholes pumping at high yields

61 Jean-Christophe Comte et. al, Challenges in groundwater resource management in coastal aquifers of East Africa: Investigations and lessons learnt in the Comoros Islands, Kenya and Tanzania, Journal of Hydrology: Regional Studies 5, pp. 179–199 (2016)

44

surrounded by otherwise freshwater groundwater, when the pumping water level elevation starts to approach mean sea level, even if the rest (non-pumping) water level is elevated above it.

Many of the older wells were hand dug and are constructed of caissons. They were reportedly excavated with explosives. A photograph of TP5 is shown below. Given its high pumping rate for minimal drawdown it is not obvious how the well was successfully constructed unless it only penetrates <2m below the groundwater table.

Plate 2: Photograph of TP5 excavated using concrete caissons

The figure below shows pressure and salinity dataloggers records (measuring groundwater elevation and salinity (electrical conductivity)) in the coastal wells at (a) well SHA at Hahaya (by the airport on the west coast, (b) well TP5 at Vouvouni just south of Moroni and (c) well ONU 40 at Oichili on the east coast.

They all show a strong tidal signal in both the groundwater elevation and the salinity. What is unusual is that TP5 has the lowest groundwater elevation but also the lowest salinity. This suggests that on the one hand the rock has high transmissivity to the coast, yet the tidal signal is somewhat dampened, and oddly it has a very low salinity – this must be due to high recharge and rapid recharge flow to the well.

45

Figure 1718: Pressure and salinity dataloggers records in the coastal wells at (a) well SHA at Hahaya, (b) well TP5 at Vouvouni and (c) well ONU 40 at Oichili.

Indeed ONU40 at Ochilli has the highest electrical conductivity and largest tidal fluctuation suggesting strong connectivity with the sea, but does not have the lowest groundwater level elevation. This again suggests recharge, or rather a lack of it, is the main controlling factor.

ONU40 at Ochilli is closest to the coast (1.5km), then TP5 (2km) then SHA at Hahaya (2.5km). The hydraulic gradients (elevation/distance) are therefore inconsistent between the boreholes. It is possible of course the figure above is not showing an actual groundwater level reading to datum but just the water column thickness above the datalogger. Assuming the groundwater elevation is to absolute datum then the hydraulic gradients are 7 x 10-4 for SHA, 5 x 10-4 for TP5 and 1 x 10-3 for ONU40. These are all shallow, but those at 10 -4 are very shallow and suggest highly permeable strata containing open conduits (i.e. lava tubes).

Mean groundwater elevations of 1.0 to 1.5m AmSL (metres above mean sea level) suggests a thickness of fresh groundwater should exist below the water table of the order of 20 to 30m thickness. Clearly however this is not the case at Hahaya and Ochilli, where salinities are nearly 2000 and 4000 uS/cm respectively.

Aquifer hydraulic properties have been estimated by earlier studies, although these would appear to be affected by tidal signals to some extent. ONU4 was estimated to have a permeability of 10 -2 m/s – this is incredibly permeable and suggests the well has encountered open conduits – i.e. lava tubes, or at the very least highly auto-brecciated blocky lavas.

46

Well ID Salinity (mg/l)

Populations Served

Flowm3/hr

Flow l/s

X Y Location

Hahaya 1500 4000 30 8 43° 27’15’’ 11°53’56’’ Ha hayaONU 3 1550 3967 40 11 43°43’18’’ 11°86’87’’ FoumbouniONU 8 2100 4 644 30 8 43°34’16’’ 11°39’38’’ OuellahONU 9 850 2630 87 24 43°29’46’’ 11°82’37’’ ChouaniONU 10 780 1112 30 8 43°46’97’’ 11°91’80’’ Sima MboiniONU 15 1600 1759 20 6 43°48’89’’ 11°92’46’’ ChindiniONU 17 240 1331 10 3 43°49’77’’ 11°91’38’’ OuropvéniONU 19 1350 1644 34 9 43°43’39’’ 11°71’89’’ M’tsagadjouONU 23 1700 4225 76 21 43°40’89’’ 11°42’02’’ N’droudéONU 27 1780 1437 50 14 43°31’56’’ 11°38’96’’ Memboi MboiniONU 28 890 14041 40 11 43°27’60’’ 11°44’79’’ ChamléONU 33 2800 4999 15 4 43°27’28’’ 11°46’91’’ N’tsaouéniONU 35 410 4196 70 19 43°26’99’’ 11°78’79’’ SéleaONU 37 850 5402 67 19 43°27’98’’ 11°81’27’’ MitsoudjéONU 38 2845 43°28’73’’ 11°84’35’’ Bangoi HambouONU 39 1500 3848 30 8 43°36’73’’ 11°85’42’’ MakoraniONU 40 1000 3 778 50 14 43°36’73’’ 11°85’42’’ KoimbaniONU 41 2000 2050 40 11 43°45’13’’ 11°76’46’’ PidjaniONU 42 2500 1 536 43°34’92’’ 11°85’20’’ DzahadjouONU 43 1500 3149 16 4 43°36’16’’ 11°71’10’’ Bangoi KouniONU 44 450 2786 40 11 43°50’75’’ 11°88’75’’ MaléTP1 450 220 61 43°24’99’’ 11°73’92’’ MdéTP5 270 400 111 43°25’29’’ 11°75’38’’ VouvouniONU 4 450 160 44 43°25’29’’ 11°75’38’’ Vouvouni

Table 9: Table of Production Borehole Properties.

Pumping rates for the freshest water wells are very high by global standards: TP1 61 l/s (450 mg/l), TP5 110 l/s (270 mg/l), ONU4 45 l/s (450 mg/l), especially when attempting to exploit fresh groundwater lenses, which are highly sensitive to vertical flows which destabilize the lateral density transition between the shallow freshwater overlying the denser saline groundwater. Usually higher pumping rate wells can be expected to pump more brackish groundwater.

ONU40 at Ochilli has a more normal pumping rate (13 l/s) but this too is quite elevated for abstraction from a vertical well/borehole within a freshwater lens.

A more detailed datalogger time series for the wells near Hahaya shows that pumping lowers groundwater levels by approximately 10cm and this corresponds with an increase in salinity of 30 uS/cm, whereas cessation of pumping results in a rise in groundwater levels of 10cm and a drop in salinity by 30 uS/cm.

47

Figure 1819: More detailed datalogger time series for the wells near Hahaya.

This suggests there are other influencing factors contributing to the low salinity yet high yielding wells in the coastal plain south of Moroni, although these are currently poorly defined.

An inspection of the geological maps and terrain, suggests these factors could be a combination of proximity of i) storm run-off channels off Mt Karthala acting as enhanced linear recharge zones to the underlying aquifer; ii) coastal cinder cones acting as groundwater flow barriers, preventing/reducing saline intrusion back into the basaltic lava aquifer; and iii) proximity to historic lahar /mudflow deposits mapped in the vicinity of the coastal cinder cones which could act an impermeable cap to further restrict coastal saline water entry back into the aquifer.

This suggests not only is the area south of Moroni appropriate for further potential exploitation but also similar areas with storm run-off channels and/or coastal cinder cone barriers elsewhere on Grand Comore may also be priority locations for further groundwater production boreholes.

48

Map 1: Geological map of Grande Comoros and location of boreholes.

What is clear however, is that the current level of hydrogeological investigation of the groundwater resources both at an aquifer wide scale to characterise the freshwater lenses and more specifically understand its

49

vulnerability to climate change induced sea level rise and rainfall-recharge reduction , as well as to assess and optimise individual well/borehole design and pumping rates to minimise saline up-coning risk during periods of climate change lengthened drought, is wholey inadequate and verging on negligble.

This has resulted in a large number of production wells/boreholes (40 out of 50) and their supply networks being constructed that are so brackish as to be effectively unuseable for potable water uses (drinking and cooking) without mixing with rainwater.

There is currently no active groundwater monitoring programme in the country to monitor salinity and pollution risks to existing boreholes and plan future expanded exploitation of the groundwater resources, nor assess how it responds to extreme drought conditions, and it appears there has never been one in the past. The thickness and distribution of the freshwater lenses and nature of the perched aquifer supporting high elevation springs on the islands is unknown.

Plate 3: Photograph of coastal plain containing the freshwater water supply wells for Moroni (capital visible in distance) – note craters adjacent to coastline.

The previous focus on using dug well technologies whilst potentially helpful in increasing surface area of the borehole and perhaps accidentally restricting well depth to 1-2m penetration into the freshwater lens, has however resulted with wells being unnecessarily close to the coast – so as to excavate at low ground

50

elevations, increasing saline risks – and means over reliance and therefore excessive pumping rates at wells which are consequently brackish.

Whilst self-evidently Comoros has managed to exploit groundwater year-on-year without having a robust understanding of its groundwater resources, the effect of climate change upon this resource, especially if it is to be the drought resource for the population currently reliant on rainwater harvesting and therefore to see an increase in its exploitation during drought periods, means it is therefore necessary to both undertake a robust national groundwater characterisation programme including hydrogeological investigations developing a multi-level piezometer network across all three islands, as well as undertaking scientific pumping tests of all boreholes proposed for production, including monitoring of surrounding groundwaters using observation boreholes.

Given only 0.5% of the renewable groundwater resource on the Grand Comore is currently being utilized and there is a proven year round fresh groundwater resource south of Moroni, groundwater provides an ideal strategy for addressing the predicted climate change introduced dry season failure risks associated with rainwater harvesting on the island. Indeed in an ad hoc way, this reliance on groundwater by these communities already happens through the use of road tankers and rural community visits to the coastal town water supply outlets.

Well Head Protection and Borehole Sanitary Hygiene / Water Safety

It is evident that the groundwater supply for Grand Comore is reliant on about 10 No. fresh-ish wells for its potable drinking water. However photographs of the wells (see TP5 above and ON39 below) show them to have almost no headworks whatsoever, being open to the atmosphere, with negligible wellhead walls, poor sanitary conditions around the wells and easy direct access to pollutants and vermin.

Plate 4: Photograph of water well ON39.

All of these open wells are therefore highly vulnerable to contamination vectors originating at or near ground surface, including fuel oil spills, wastewater and high turbidity storm run-off. There appears therefore to be a

51

lack of adequate understanding of hazards and risks posed to raw water quality, including climatic risks, and a complete lack of Water Supply Safety Planning.

This lack of well head protection became manifest during the April 2012 floods, when TP5 (the main water well for Moroni) was inundated by storm flood-waters, resulting in high turbidity debris flows entering, damaging, contaminating and blocking the water well. This was all the worse in 2012, as the storms mobilized the most recent ash falls from the 2007 volcanic eruptions, resulting in storm run-off being more appropriately described as more like lahars i.e. mudflows.

Clearly increasingly intense rainfall events (GCM predict up to 45% increases in rainfall intensity – see Section 1.3) will make these overland storm water run-off flow events and their mobilized suspended debris (Section 1.3 identifies potential increases in erosion rates of up to 200 times non-climate change conditions) more common and more extreme and therefore pose an even greater threat to poorly protected wellhead surface infrastructure.


Grand Comore has significant quantities of accessible and exploitable groundwater resources which currently provide year round freshwater supply to the coastal towns, villages and capital city, including during the dry season.

The groundwater resources are however non-uniform around the island with brackish groundwater being encountered in all coastal areas except for the south-west of the island, resulting in many boreholes being unpotable (but not unusable) due to elevated salinity.

A lack of robust groundwater investigation and monitoring prevents both identification of further exploitable drought resilient groundwater resources but also reduces protection of existing freshwater resources from salinity risks from climate change extended dry periods. Specifically there is no estimate of the thickness of the freshwater lens and therefore its current vulnerability to extended periods of drought is unclear.

An island wide groundwater regime monitoring system is required using multi-level piezometers to investigate and monitor groundwater resource abundance, responses to reducing annual recharge as well as extended drought periods, as well as operational monitoring of pumping rate, salinity and water levels.

The likely replenishment rate of the aquifer south and west of Mt Karthala is itself provisionally calculated to be sufficient to supply the entire population of the island, but a lack of detailed technical knowledge of exactly how existing production wells abstract groundwater from the surrounding volcanic rocks prevents an accurate assessment of the vulnerability of individual wells to saline up-coning during climate change extended drought periods. This is a particular concern because the current water supply relies upon relatively few wells per supply zone, many of which are pumping at extremely high pumping rates, which makes them vulnerable to salinity, and some bores of which are already close to salinity limits for potable use.

Detailed technical assessment of the geology and hydrogeology at each production well needs to be undertaken, including controlled pumping tests and monitoring of adjacent groundwater within multi-level piezometer nests. This will allow optimum site selection and design to provide water in extended drought conditions at pre-determined pumping rates, including additional drought season boreholes required to

52

support communities otherwise reliant on wet season rainwater harvesting. Particular attention should be given to understanding why Well TP5 has such a high yield and such a low salinity.

The dependence on a handful of hand dug (with caisson rings) wells places greater risk on the water security of supply. Pumping at lower rates from a larger number of boreholes will reduce salinity risk and increase outage capacity – for example if wells are polluted by climate change accelerated storm run-off.

Pumping at smaller pumping rates also means conventional boreholes can be used for construction purposes, which means that boreholes can be drilled to greater depths and therefore can be located at greater distances from the coast – both of which will reduce salinity risks.

All wells and boreholes need to be assessed for vulnerability to storm overland flow inundation pollution risks and mitigation measures put in place – including above ground head works, covered and sealed annulus, protection walls and roofs, and boundary fences and gates. This should be undertaken as part of a wider Drinking Water Safety and Security Planning (DWSSP) framework, considering water quality and water quantity risks.

Water source vulnerability to storm related floods will also require operational & maintenance responses and therefore should be informed by forecasting and early warning of such events.

1.2.2 Groundwater on Anjouan

Information on groundwater resources in Anjouan is much more limited than on Grand Comore. Previous studies have identified its limited use62, exploited through a combination of a small number of wells, high elevation spring capture works, and dry season base flows to streams.

The most detailed study of groundwater resources on Anjouan was undertaken by Charmouille 63 in 2012. This work included hydrochemical analysis of wells, springs and streams, as well as almost 4 years of stream flow gauging of a high level water intake at Daji in the southern part of the island.

The work identified three types of groundwater aquifer:

● A deep basal main aquifer system that is intersected by the eroded valleys and provides a base flow to

streams;

● Perched aquifers which provide base flow to high level springs; and

● Small areas of alluvial deposit tracts within the larger river valleys, which are in hydraulic connection

with the rivers themselves – these were the only wells identified on Anjouan. The work enabled hydrochemistry across the island as well as dry season spring flows to be used to estimate recharge rates to the aquifers to be determined. A map of water samples locations is shown below on Anjouan as well as photograph of a hand dug well in the alluvium near Pomoni and the flow hydrograph for the perched aquifer spring fed water intake near Daji.

62 AEPA Project 2013, Etudies Techniques, du Cadre Institutionnel Et Du Programme National D’AEPA.

63 Charmoullie, 2012. Ebauche du fonctionnement hydrogeologique de l’île d’Anjouan (Comores)53

Charmouille reports high altitude groundwaters to have salinities as low as 50 uS/cm whereas the low altitude groundwaters had salinities as high as 250 uS/cm. This confirms longer groundwater flow paths to the lower altitude groundwaters, which is not surprising of course, but also suggests groundwater recharge rates could actually be as high as 20% of rainfall.

Figure 1920: Map of water samples locations is shown below on AnjouanError! Bookmark not defined.111

54

Plate 5: Photograph of a hand dug well in floodplain alluvium near Pomoni

The hydrograph shows a clear recession from peak flows in February-March of 7-8 litres per second reducing to 1 litre per second in November-December, the latter of which is evidently sustained throughout the dry season.

Whilst the peak flow measurements reflect surface water run-off – and this information will be discussed in a later section – the dry season flows are supported by groundwater contribution alone. Charmouille estimated the recharge required to sustain the groundwater baseflow was 130 mm/yr, i.e. approximately 5-10% of rainfall.

55

Figure 2021: Hydrograph of Pomoni alluvial floodplain well Error! Bookmark not defined. 111.


Groundwater in Anjouan provides a vital role in water supply on the island, primarily through sustaining dry season low flows in springs and streams, which provide the water source for stream intakes. There is estimated to be more groundwater on Anjouan than surface water, and with a much greater residency time on the island (at least 3 months to feed springs and streams).

However there is very little understanding of the groundwater resource, with no detailed investigation and no on-going monitoring of groundwater or surface water flows.

An island wide network of stream flow and quality monitoring is required, as well as a more detailed programme of hydrogeological characterisation of the island to better understand the lateral extents and yields of the perched, alluvial and basal aquifers, and to determine whether they could sustain drought period water supplies. This should include multi-level piezometers where appropriate and seasonal water quality sampling. Low flow yields of the streams need to be determined to allow future drought resilient water supply schemes to be located and sized accordingly.

Springs being exploited for year round supply also need to be protected from storm event peak flows which could damage the spring capture works and its associated conveyance infrastructure.

As with Grand Comore, more modern drilling techniques should be used to identify and exploit groundwater at further distance from the coast, which will be less vulnerable to salinity increases during drought periods. Individual borehole yields need to be robustly determined through best practice investigations and have appropriate sanitary headworks.

56

All water sources need to undergo formal vulnerability and risk assessment to develop DWSSP which should inform their design, and later operation, maintenance and re-investment programmes as well as inform watershed management plans.

Figure 2122: Previously identified possible exploratory borehole locations in Anjouan.

Previously identified possible exploratory borehole locations in Anjouan are shown above.

1.2.3 Groundwater on Moheli

The groundwater regime for Moheli is considered to be similar to that on Anjouan – the two islands being both geologically similar in structure and age.

Earlier reporting has identified Moheli as securing almost 12% of its water supply from wells, with 33% of its available water resources being considered to be groundwater, although this is minimally exploited – estimated to be currently providing 5-6 l/s for the entire island.

In 2003-2004, 3-4 No. 25m deep boreholes were constructed on the Plateau de Djandro. Photographs suggest these were installed with hand pumps to support village supplies. Their yields are therefore likely to be <0.5

57

l/s.

As with Anjouan however, groundwater is likely to be an important component of sustaining dry season base flows in the stream network, upon which water supply stream intakes are highly dependent. Given the terrain steepness and reported deep weathering of the volcanic bedrock, groundwater recharge is likely to be less than 10% of rainfall. That said, the central plateau in particular may receive considerable infiltration and act as a header/supply tank to the surrounding streams.

However there has been no groundwater investigation on Moheli and there is no on-going groundwater or surface water monitoring of flows or water quality.


Groundwater is a poorly defined but important water resource in Moheli, supporting as it does dry season stream low flows. Due to the small size of many of the surface water catchments, these are likely to rely heavily on the groundwater discharges to sustain flows.

It is important to set up an island wide groundwater and surface water monitoring network to measure springs, stream low flow periods, as well undertake groundwater investigation and characterization of the perched and basal volcanic aquifers as well as identify and investigate any alluvial tract deposits, to inform future decisions on whether to exploit the groundwater to provide drought resilient water supplies.

Wells and spring capture boxes require protection from storm event mobilized surficial pollution and need appropriate hard infrastructure sanitary protection as well as controls on adjacent land use. DWSSP should be adopted in a systematic manner to assess and treat climate change water quantity and water quality risks to these sources.

Previously identified possible exploratory borehole locations in Moheli are shown below.

58

Figure 2223: Previously identified possible exploratory borehole locations in Moheli

1.3 Climate Change Risk and Impacts on Surface Water Resources

As has been described earlier, Anjouan and Moheli are dominated by run-off catchments whereas Grand Comore only has storm run-off channels.

The following section therefore only considers Anjouan and Moheli.


Renewable Surface Water Resources m3/yr

Surface Water Exploited m3/yr

% Surface Water Exploited

Grand Comore

1 254 066 200124 148 250 (10%)

2,338,982 (Rainwater Harvesting)

1.9

Anjouan

513 830 200213 928 000 (42%)

6,302,462 2.3

Mohéli 117 236 400 78 496 000 (67%)

1,133,215 1.2

59

Table 10: Table of water resource exploitation.

1.3.1 Surface Water on Anjouan

There are 44 watershed basins identified in the National Water Strategy and Programme (see Figure 23 below, and Appendix 1- Natural characteristics and land use maps. The largest is

Figure 2324: Map of the 44 watershed basins on Anjouan as identified in the NWSP

13km2, the smallest is 0.5km2, with the maximum length being 7km. The catchments are therefore not only small and short, but they are also steep – with the centre of the island more than 1500m in elevation.

The catchments can therefore be described as very ‘flashy’, meaning they respond rapidly to rainfall, and will have low flows entirely reliant on groundwater baseflow – there being no lakes or substantive wetlands to retard and attenuate rainfall run-off.

Mutsamudu Basin Flow Estimation

There is very little detailed characterisation of the watersheds, with the exception of the Mutsamudu Watershed64 on the north coast (Catchment No. 33 on Figure 23) and the Daji65 upland catchment (No.20) in south-central uplands.

The Mutsamudu Watershed with an area of 7km2 and of length of 7km was extensively described in 2015 as part of the UNDP/UNEP Indian Ocean IWRM Programme and a watershed management plan developed. The

64 Raphael Tshimanga, 2015. Mutusmudu Watershed Integrated Management Plan. UNEP IWRM SIDS Programme.

65 Charmoullie, 2012. Ebauche du fonctionnement hydrogeologique de l’île d’Anjouan (Comores)60

catchment morphology was detailed from satellite imagery confirming very steep slopes (>45 degrees) for 12% basin area, steep slopes (26-45 degrees) for 44% of the basin area and fairly steep slopes (13-25 degrees) for 26% of the basin area, i.e. almost 85% of the basin has slopes >13 degrees. Land use was also described in detail – 30% forest, 60% cropped, 10% urban.

However even this extended study only was able to use mean average monthly flow estimates to evaluate the water resources of the watershed – there being no active on-going water flow or quality monitoring.

Highest stream flows (830 l/s) were reported in February, March and April, and lowest flows (120 l/s) in November. Monthly rainfall and flows obviously do not allow identification of storm floods, but there appears to be a delay between seasonal rainfall reducing and reducing stream flow of approximately 2-3 months, and a delay of 1-2 month between increasing rainfall and increasing stream flow.

Figure 2425: Normalised flows in Mutsamudu Watershed tributaries Error! Bookmark not defined. 112.

A reported average flow of 400 l/s would require an annual rainfall of approximately 3000mm/m 2/yr to support this flow.

Reported low flows of 120 l/s would suggest a groundwater recharge of perhaps 500mm/m 2/yr, i.e. 20% of rainfall, depending on elevation and location.

Daji Captage Flow Estimation (Agnochi Watershed)

A second study (Charmouille, 2012) on stream flows in Anjouan was undertaken at the Daji Intake Captage just south of Adda. This monitored stream flow just upstream of the intake, which was known to be partially fed by groundwater springs – this work has been referred to in the groundwater section above – but which included year round stream flow monitoring between 2007 and 2012. Part of this hydrograph is shown below for 2010-2011 (the full hydrograph is in the groundwater section of this report).

61

Figure 2526: Hydrograph for 2010-2011 at the Daji Intake Captage just south of AddaError! Bookmark not defined. 113.

The hydrograph shows a seasonal peak flow of 7-8 l/s in February-April and a seasonal low flow of 1 l/s in November-December – the timings and ratio of peak to low flow (7:1) are consistent with the Mutsamudu Basin findings. The difference here is the Daji catchment is much smaller, reported as 25 hectares (0.25km 2), is only at high elevation(>500m AmSL), and is known to have a contributing dry season base flow supported by groundwater (springs).

An annual average flow of perhaps 4 l/s over a possible catchment of 25 hectares suggests a unit contribution rate of 500mm/m2/yr. This seems low and suggests either the water source is dominated by groundwater fed baseflows or the peak run-off flows are absent from the weekly flow measurements.

The hydrograph above does show a rapid rise in stream flows within 2 weeks of rainfall in January (although it should be noted the flow readings are weekly) but also shows drops in stream flow within 2 weeks of dry weather, as well as an unseasonal rise in July 2011, 2 weeks after heavy rainfall.

Whilst it is difficult to determine is whether the delay is attributable to attenuation through the perched groundwater system or through the terrain and eco-system habitat that might retard surface water run-off, this is perhaps of less significance than the timing delay between rainfall and stream flow being identified.

It should be noted of course that weekly flow measurements will not identify rapid run-off responses due to high rainfall intensity storms – however these flow hydrographs are the only ones identified to exist for the country.

62

Perennial and Ephemeral Rivers

Figure 2627: Map of changes in year round flowing streams on Anjouan

There is a widely perceived but evidence poor understanding by water sector professionals that the rivers in Anjouan are reducing in flow. The map above reports work by Astudillo (2012), showing the changes in year round flowing streams on Anjouan. It is noticeable the stream identified as flowing year round in 1955 but not in 1973 are mostly restricted to the smaller catchments on western and southern peninsulas.

Dry Season 2011 and 2012 Reported Flows

A series of ad hoc stream flow measurements are reported by the National Water Strategy and Programme for November 2011 and October-November 2012. With a few exceptions, these report flows to be < 1 l/s at almost all locations.

When compared to the 12 month drought index (developed by the proposal design process) it is clear the 12 month period preceding the 01 July 2013 was the driest and most sustained 12 month period in the last 50+ years. However the three month drought index shows the 2012 dry season to be less severe than any other year since 2009. Indeed it confirms the 12 month dry ranking for July 2013 to be primarily a function of a less wet than usual 2012/2013 winter.

63


Whilst the 3 month drought index does confirm Oct-Nov 2012 low flows may have been even lower in later years (2014 and 2015), it also demonstrates the driest dry seasons have all been experienced in the last 6 years – further evidence of the on-going impact of climate change.

64



The stream watersheds on Anjouan are small, steep and narrow with negligible natural storage (e.g. no lakes and wetlands) within them. The watersheds will therefore respond rapidly to intense rainfall events. The catchments can be expected to therefore be susceptible to GCM predicted increasingly intense rainfall events (+45%) which are likely to both damage and block surface water intakes.

The few studies of surface water resources strongly indicate an important groundwater fed baseflow low flow component, which sustains natural flows, albeit at low levels in the studied catchments. These base flows are the only water resource the island populace will have during dry season periods. These flows can be expected to reduce commensurate with the 15% reduction in annual rainfall predicted by the GCMs, if not greater reductions.

Maximising the capture of these stream low flows is essential to increasing resilience to increasingly frequent and longer duration dry periods.

There is no characterisation of stream flow or water on the island nor any operational flow and quality monitoring. Whilst this has been acceptable during non-climate change conditions, an island wide programme must be implemented at the first opportunity to understand how quickly the stream flows respond to rainfall variability and inform estimates on increased turbidity due to increases in erosion.

It is important to guide detailed re-design of water intakes to be resilient and flexible so as to allow capture of both low flows and be resilient to damaging flood flows, both of which are predicted to become more extreme

65

with climate change. This should include low level intakes, ability to close intakes during high turbidity flows, intake over-topping arrangements, and access routes, pipelines and storage tanks located away from the flood flow corridors. This requires an assessment of flood risk zone mapping.

Storage should be built into the gravity delivery systems to enable the intakes to be closed for short periods during storm events – to prevent sediment ingress – and to continue to allow the supply of water during low flow periods.

This requires an adaptation capacity at the operation and maintenance level of the water service provider as well as a reliable and timely forecasting capacity for flood risk and drought risk.

Water treatment needs to be upgraded at the water supply schemes. Turbidity of raw water is likely to increase and water quality decrease with increasingly common more intense rainfall events (+45%), resulting in normal drinking water quality deteriorating (potentially with suspended solids increasing by 1-2 orders of magnitude) below that which the local populace has developed a level of resistance. Thus water treatment is required to overcome this decrease in raw water quality.

1.3.2 Surface Water on Moheli

There are reported to be 25 watersheds on Moheli identified in the National Water Strategy and Programme. The largest is 9km2, the smallest is 0.45km2, with the maximum length being 5km (see Figure 29 be low and Appendix 1 – Natural characteristics and land use maps). The catchments are therefore not only small and short, but they are also steep – with the centre of the island more than 750m AmSL elevation.

Figure 2930: Map of 25 watersheds on Moheli.

The catchments can therefore be described as very ‘flashy’, meaning they respond rapidly to rainfall, and will have low flows entirely reliant on groundwater baseflow – there being no lakes or substantive wetlands to

66

retard and attenuate rainfall run-off.

Low flows (<0.5 l/s) were measured in high elevation streams in east Moheli 66 (annual rainfall 1500mm/yr) during the 2007 dry period in 12 out of 15 locations, although the other 3 locations measured 5, 7.5 and 21 l/s.

There is no known active flow gauging on Moheli for any of the stream networks.


The almost complete lack of information for Moheli means Anjouan serves as an analogue of the state of its surface water resources. The Anjouan conclusions and recommendations are therefore as equally relevant to Moheli, and are repeated below verbatim:

The stream watersheds on Moheli are small, steep and narrow with negligible natural storage (e.g. lakes and wetlands) within them. The watersheds will therefore respond rapidly to intense rainfall events. The catchments can be expected to therefore be susceptible to increasingly intense rainfall events (+45%) which are likely to both damage and block surface water intakes.

The few studies of surface water resources on Anjouan strongly indicate an important groundwater fed baseflow low flow component is likely to exist on Moheli, which sustains natural flows, albeit at low flows in the studied catchments. These base flows are the only water resource the island populace will have during dry season periods. These are expected to reduce by at least 15% due to climate change.

Maximising the capture of these stream low flows is essential to increasing resilience to increasingly frequent and longer duration dry periods.

There is no characterisation of stream flow or water on the island nor any operational flow and quality monitoring. Whilst this has been acceptable during non-climate change conditions, an island wide programme must be implemented at the first opportunity to understand how quickly the stream flows respond to rainfall variability and inform estimates on increased turbidity due to increases in erosion.

It is important to guide detailed design new water intakes to be resilient and flexible so as to allow capture of both low flows and be resilient to damaging flood flows. This should include low level intakes, ability to close intakes during high turbidity flows, intake over-topping arrangements, and access routes, pipelines and storage tanks located away from the flood flow corridors. This requires an assessment of flood risk zone mapping.

Storage should be built into the gravity delivery systems to enable the intakes to be closed for short periods during storm events – to prevent sediment ingress – and to continue to allow the supply of water during low flow periods.

This requires an adaptation capacity at the operation and maintenance level of the water service provider as well as a reliable and timely forecasting capacity for flood risk and drought risk.

Water treatment needs to be upgraded at the water supply schemes. Turbidity of raw water is likely to increase (potentially by 1-2 orders of magnitude) and water quality decrease with increasingly common more intense(+45%) rainfall events, resulting in normal drinking water quality deteriorating below that which the

66 UCEM, 2008. Schema Directeur pour ‘approvisionnement en Eau des populations de la region de Djandro

67

local populace has developed a level of resistance. Thus water treatment is required to overcome this decrease in raw water quality.

1.4 Climate Vulnerability Mapping and Target Zone Selection

1.4.1 Climate vulnerability distribution mapping process

A national consultation process on climate variability within Comoros was undertaken as part of this project design process. Facilitated by UNDP, the participatory consultation was undertaken between November 2015 and November 2016 using an expert stakeholder group involving senior national experts from the key line ministries and island agencies in a series of workshops. The consultation process included a review of water supply vulnerability based upon group evaluation of existing water supply feasibility studies, as well as national climate vulnerability and disaster risk management assessments, followed by expert discussions. Consultation documentation is enclosed in Appendix 6 – Consultation, Meeting and Engagement Documents.

The country was divided into 26 zones. The vulnerability of these zones were then assessed using 34 metrics covering 8 criteria groups: climatic impacts, type and condition of water resources, land degradation, role of women in water management, socio-economic vulnerability, on-going governmental and non-governmental programmes, and likely ease of project implementation (e.g. accessibility). The zones were then ranked based upon a summation of climatic and socio-economic vulnerability and an overall ranking derived which included other on-going similar project initiatives and ease of project implementation (see Appendix 7 – Selection of Intervention Zones).

Using these criteria the most vulnerable zones to climate risks which were not receiving on-going or planned climate adaptation support were identified. Of the 19 most vulnerable zones identified, 4 already had other development partners working in them, resulting in 15 zones being selected as targets for the GCF project.

The 15 target zones on the three islands, comprising 103 villages, were therefore chosen due to their vulnerability to climate change, their good hydrogeological and hydraulic potential for water storage and capture, limited donor support for water supply in the localities to date and a potential collaboration planned with complimentary donor support.

1.4.2 Target villages

Target sites on the three islands have been chosen due to their vulnerability to climate change, their good hydrogeological and hydraulic potential for water storage and capture and a future collaboration planned with donor support in other regions and/or complimentary.

Funds will be distributed according to i) quantified and qualified climate variability of the villages, ii) the village’s capacities to implement community-based water monitoring and iii) ability of the project target sites to maximize contributions to the Comoros’ development goals. A mix of Rainwater Harvesting (RWH) and groundwater exploitation will be used on Grand Comore. These water capture methods were chosen because there is a complete lack of surface water resources on Grande Comore due to the volcanic nature and high porosity of the soil. Conversely, a mix of RWH and river surface water capture will be used on Anjouan and Mohéli.

68

The selection criteria are based on the village vulnerabilities analyzed during the CRCCA and ACCE projects as well as the NAPA (see Appendix 7 - Selection of intervention zones).

Selection criteria include:

Vulnerability (higher score indicates more vulnerable):

Environment for project interventions(higher score indicates more chance of success):

Flood (intense precipitation) / drought (prolonged dry season) risk

Presence of women-based associations

Exposure to cyclones Roles for women in Water User AssociationsErosion / sedimentation Groundwater resources availableBiodiversity risk Surface water resources available

Degree of soil degradation, deforestation Access to water distribution pointsDegree of pollution (e.g., from solid waste) On-going projects / programmes in regionLimited livelihood diversification strategies / Economy dependent on rain-fed subsistence agriculturePoverty, Malnutrition, Unemployment, Population growthWater-related diseases

Table 11: Table of selection criteria used for targeting villages.

The target zones include (see Appendix 8 - Selected zones of intervention):

Grande Comore Zones: 1) Bambao et Itsandra et peri-urban Moroni, 2) Ngongwe, 3) Hambou Djoumoipanga, 4) Mboikou, 5) Oichili, 6) Hamanvou (see Appendix 9 - Intervention zone infrastructure maps);

Anjouan Zones: 7) Hassimpao, 8) Vouani, 9) Vassi, 10) Ankibani, 11) Chitrouni – Saadani, 12) Mjamaoué, 13) Nioumakélé-Bas (see Appendix 9 - Intervention zone infrastructure maps);

Moheli Zones: 14) Fomboni-Djoiezi, 15) Hoani-Mbatsé (see Appendix 9 - Intervention zone infrastructure maps).

69

Figure 3031: Location map of the target communes on all three islands (Source: National Experts Oct 2016)

70

POLICY AND INSTITUTIONAL FRAMEWORKS RELATED TO CLIMATE CHANGE ADAPTATION, WATER AND SANITATION

2.1 Overview

Climate Change

The Government of Comoros ratified the United Nations Framework Convention on Climate Change in 1992 and submitted its National Adaptation Plan of Action (NAPA) in 2006. NAPA priorities are aimed at adaptation in water and agriculture. The NAPA identifies loss of water bodies, drought and low river flows and climate-related storms as major threats and hazards to Comoros. It also identifies water availability, food security and income generation as the main issues vulnerable to climate change. Some of the priority adaptation projects identified in the NAPA are i) increase water supply and increase its quality; and ii) fight against soil erosion and promote restoration and reconstitution of basin slopes.

The Initial and Second National Communications (INC (2003) and 2NC (2012) respectively) to the UNFCCC,67

identify Comoros’s principal environmental problem to be water scarcity, the ephemerality of surface water and the salinity of groundwater.

Comoros’s recently drafted Accelerated Growth and Sustainable Development Strategy (2015 – 2019) (Stratégie de Croissance Accélérée de Développement Durable or SCA2D) aims to make the Comoros an emerging country by 2040.68 Two of the four objectives of the SCA2D are i) to improve the population’s living conditions and ensure equity in the access to basic social services; and ii) to promote the Comorian natural and cultural heritage and the optimal use of natural resources.

Finally, the Project supports Comoros’s aim in achieving the Sustainable Development Goals (SDGs). The project will address SDG 2 – food security and SDG 6 – sustainable water management and SDG 11.

Decentralization

The Ministry of the Interior, Information and Decentralization is responsible for defining the main orientations and putting in place the reforms that must be undertaken within the framework of the implementation of the International Guidelines on Decentralization and Access to Basic Services for All at the National Level. Decree N ° 11-147 / PR, of April 07, 2011, promulgating the law n ° 11-005 / AU, of May 02, 2011, giving territorial organization of the Union of the Comoros presents the organization of the Union Comoros in the new context of decentralization. Framework Law No. 94-018 of 22 June 1994 on the environment establishes the decentralization of actions and the empowerment of decentralized entities such as public, rural or urban authorities within the framework of its competences and takes the necessary measures to the improvement of the living conditions of the populations.69

67 Comoros’s Initial National Communication to the UNFCCC 2001

68 Stratégie de croissance accélérée et de développement durable 2015-2019 (SCA2D) (May 2014)

69 IWRM Road Map for the Comoros 201571

Water policy

The Water Act (1994) states water resources management should be led by MA-MWE (Autonomous Agency for Water and Energy Distribution) in urban areas and by the Ministry of Production in peri-urban and rural areas whereas the 2011 decree on the Decentralization Process that stipulates that water and sanitation management is attributed to communities on the three islands.

The Organic Law, signed on 1 March 2005, divides the sectorial powers between the Union and the Autonomous Islands. Its article 10 stipulates that "Water policy [...] falls within the competence of the Autonomous Islands which exercise it within the framework of the national development policy ... defined by the Union in consultation with the Autonomous Islands." "The Union, in consultation with the island executives, shall contribute to the balanced equipment and services of the islands in the matter of water, in accordance with the national plan."

2.2 National development policies

2.2.1 National climate change policy

Strictly speaking, there is not yet a real policy on climate change. However a strategy for the diversification of energy sources is being elaborated, as well as several adaptation actions in different fields. 70

However, the second national communication on climate change71 lists a series of actions that would help the water sector adapt to the impacts of climate change, which are summarized here:

● strengthening water resources management and environmental monitoring;

● improving groundwater management and preservation;

● expanding hydrological and meteorological monitoring infrastructure;

● protecting ecosystems and regulating stream flow;

● increasing storm run-off collection and discharge infrastructure; and

● integrating local populations into water resources management.

2.2.2 National climate change adaptation plan

The country’s National Adaptation Plan of Action (NAPA) was produced in 2006 and identified 13 priority activities that the Comoros should pursue to adapt to climate change, summarized and ranked in the table below.

Those directly pertaining to water resource management are in bold font.

70 NAPA 2006

71 Seconde communication nationale sur les changements climatiques, 201272

RANK

Options Mohéli Anjouan Grand Comore

Country

1 Varieties that better resist drought 2 1 2 12 Defence and soil restoration 5 2 4 4 3 Reconstitution of basin slopes 6 5 6 64 Increase of water supply 4 3 1 2 5 Improvement of water quality 3 4 3 3 6 Fight against malaria 1 6 5 5 7 Non-metallic local construction material 11 7 10 7 8 Fodder production 13 8 11 13 9 Provender production 12 12 9 12 10 Introduction of FCM 7 11 13 9 11 Fish conservation under ice 9 13 7 1112 Early warning 10 9 8 8 13 Support to eye care and surgery 8 10 12 10

Table 12: Prioritization of the options from consultations, per island, and at the national level.72

2.2.3 The Intended Nationally Determined Contribution of the Comoros

The Intended Nationally Determined Contributions (INDCs) report, drafted in the lead-up to the 2015 United Nations Climate Change Conference held in Paris, recognizes the extent to which the country’s development challenges are intimately linked with its climate change adaptation challenges. In particular, it recognizes the vulnerability of the rural and agricultural communities and the proximity between efforts to reduce poverty and those to reduce vulnerability.

Objectives outlined in the INDC that are directly related to the management of water resources include providing 100% of the population with access to drinking water by 2030, updating agricultural practices to include techniques and plant varieties and water management systems that are compatible with changes to the climate.73

2.2.4 National policy on water supply and sanitation

The National Strategy for Accelerated Growth and Sustainable Development (Strategie de croissance acceleree et de developpement durable (SCA2D))74 unites all initiatives that aim to reduce poverty and promote sustainable development. An important component involves promoting and expanding access to drinking water and sanitation to the population. This involves establishing sectorial management that is efficient, accessible, fair, and capable of meeting the entire population’s demand for drinking water and sanitation, reaching even the most vulnerable, in a sustainable and resilient way.

72 NAPA, 2006

73 INDC, 2015

74 UNION DES COMORES – Strategie de croissance acceleree et de developpement durable (SCA2D), 2015-2019 73

This involves (i) expanding access to drinking water services to the entire population; (ii) proving water treatment and quality control; (iii) integrating sanitation into the drinking water sector; (iv) redefining the scope of sanitation; (v) promoting the sanitation sector; (vi) updating political and strategic sectorial documents with respect to decentralization, integrated water resources management, and climate change; (vii) setting up a monitoring network to gather data on climate change; and (viii) setting up a transparent and efficient organization framework.

The government’s strategic objectives are:

● Reorganizing the regulatory and institutional frameworks for drinking water supply and sanitation and

identifying feasible approaches to cover the costs.

● Supporting local collectives and village organizations in their efforts to set up local drinking water

distribution and sanitation systems.

● Setting up climate sensitive projects and programmes related to drinking water and sanitation . The

objectives of the National drinking water and sanitation programme include,

● For drinking water:

o (i) Increasing the percentage of the population with access to drinking water from 22.4% in 2012 to 66% in 2020; (ii) Ensuring the viability of the drinking water and sanitation sector; (iii) Ensuring that low-income segments of the population have access to drinking water;

● For sanitation:

o (i) Increasing the percentage of the population with access to improved sanitation services from 37.7% in 2012 to 75% by 2020; (ii) Promoting rainwater purification using conventional and alternative techniques; (iii) Encouraging behavioral change for correct use of infrastructure and facilities as well as personal hygiene; (iv) Ensuring the sustainability of sanitation infrastructure, in particular in terms of its exploitation, maintenance, and renewal.75

The second national communication on climate change76 lists a series of actions pertaining specifically to adapting to climate change impacts to water resources. The report outlines includes initiatives for:

● Promoting small hydroelectric development,

● Protecting ecosystems and regulating stream flow,

● Strengthening capacities for water management and environmental monitoring,

● Preserving and improving management underground water resources,

● Expanding hydrological and meteorological monitoring infrastructure,

● Promoting the reuse of water,

● Expanding infrastructure to evacuate and collect runoff,

75 UNION DES COMORES – Strategie de croissance acceleree et de developpement durable (SCA2D), 2015-2019

76 Seconde communication nationale sur les changements climatiques, 201274

● Integrating local populations in water resource management.

2.3 Water-related institutional arrangements of Comoros

2.3.1 Current administrative organization

In Comoros, the national water policy is overseen by the Ministry for Production, the Environment, Energy, Industry, and Crafts. This involves managing the various projects in the water sector, as well as providing technical support to the state-owned MAMWÉ company that is active in the water and energy sectors.

The minister approves water tariffs and defines the regulatory and institutional framework, establishes the sectorial action plan and government policy, and monitors the implementation of development programs in the sector, in particular by seeking funding. It includes, among others, the General Directorate for Energy, Mines, and Water (DGEME).

The institutional framework for water in Comoros is set up as follows :

• Ministry of Production, Environment, Energy, Industry, and Crafts

• General Directorate for Energy, Mines, and Water

• General Directorate for Forests and the Environment

• The General Directorate of MAMWÉ.

Each of these institutions works closely with partners such as UNDP, AFD, the EU, and FADC.

The DGEME’s mission is to design, oversee, control, and coordinate programmes and actions adopted by the Ministry of Energy, Mines, and Water, but in urban and rural areas. Although a village-level hydraulic service was created in 2010, this is managed by the autonomous islands. The DGEME has two directorates : (1) The Directorate for Energy and Mines ; and (2) The Directorate for Water.

At the regional level, the islands have Commissariates in charge of Water, Energy, Transportation and Telecommunications, which work in collaboration with the Directorates.77

2.3.2 Weaknesses of the Water Code prior to 2015 Reform

An analysis of the old Water Code has reports the following:

• Low drinking water supply (less than 15%);• Demand for unsatisfied drinking water (weaknesses in investment and inadequacy of financial

resources);• Insufficient water supply capacity in all cities;• Problems of mobilizing water resources in the majority of areas where there is urgent request.• Absence of a sectoral water policy and strategy;• Absence of a climatic-hydrological observation network and piezometers;• Inefficiency of institutions responsible for water management and operation;

77 Diagnostic approfondi de la ressource en eau pour approvisionnement des iles comores, Version définitive – Avril 2016 75

• Lack of a clear and permanent mechanism for coordination and communication between the various actors involved in the promotion and development of the sector;

• Incomplete legal framework;• Absence of a sectoral water master plan;• Lack of reliable databases on water resources (potential, mobilized level, volumes exploited by sectors

and exploitation rates);• High costs of drilling for reconnaissance and groundwater drilling due to very hard volcanic rocks and

which require significant technical means;• Inadequate technical capacity in the management of water supply networks;• The MA-MWE is in difficulty: its DWS service, even after it has limited itself in Moroni is far from

satisfactory, water supply is marginalized in the face of electricity;• No program contract (rights and obligations) is signed between MAMWÉ and the State;• Lack of equipment and support for water supply systems;• Water from different systems is not systematically treated;• Lack of adequate maintenance of water systems;• Low cost recovery for water system operations;• Lack of tariff policy. The MA-MWE applies a flat fee system administered (220 KCF, without updating

mechanism);• Sharing of responsibilities and relations between the different actors (central administration, regional

administration, local authorities, water management society, CGE) not sufficiently institutionalized;• Inadequate / inadequate mechanisms to guarantee access to drinking water for disadvantaged groups.

2.3.3 Water Code Reform

Drinking water is governed by the water code (loi 94-037 du 21 Décembre 1994) enacted in 1994. It has since then set the principles underlying Comorian water policy:

● Centralization of water governance

● Public ownership of water resources

● Mobilization, distribution and protection of water resources

● Treatment of high priority water

● The chosen sectorial management approach adopted 78

In 2013, AfDB began supporting the Comoros in reforming its Water Code. This included reforming the institutional framework for water management with the following objectives:

● Ensuring universal and sustainable access to drinking water and sanitation services by 2030;

● Repositioning the sanitation sector at the same level as the drinking water sector in the form of a

single drinking water and sanitation sector;

● Redefining the content and scope of sanitation in the Health and Environmental Strategy (2009).

78 Diagnostic approfondi de la ressource en eau pour approvisionnement des iles comores, Version définitive – Avril 2016 76

● Expanding water treatment to provide potable water;

● Upgrading the water treatment sector;

● Successfully integrating the gender dimension;

● Adapting political and sectorial strategic documents to the context of decentralization and IWRM;

● Setting up a transparent and efficient organizational framework.

The new Water Code was approved for ratification by parliament in 2015, but is currently awaiting parliamentary approval and is yet to be implemented. The new Water Code demonstrates the need to strengthen the water sector and the requirements to do this have been carefully assessed and are now enshrined in law. However it should be emphasized that the new Water Code in no way addresses the issue of adapting to and building resilience against climate change.

According to the National Water Supply and Sanitation Program and Strategy the reform would strengthen the institutional framework through:

● The establishment of a regulatory and good governance mechanism for the water and sanitation

sector;

● The restructuring of the General Directorate of Energy, Mines and Water(Direction Générale de

l’Energie, des Mines et de l’Eau, DGEME) into a General Directorate of Water and Sanitation, Direction Générale de l’Eau et de l’Assainissement, DGEA with a Regional Directorate of Water and Sanitation, Direction Régionale de l’Eau et de l’Assainissement, DREA at the level of each island; It is advised to create a General Directorate specific to Energy and Mines;

● The creation of three regional water and sanitation companies (one per island) for the management of

urban DWSS networks. These companies will have administrative and financial autonomy. They will be responsible for planning the development and management of drinking water and sanitation systems. In addition to the decentralization of the public service of the Drinking Water and Sanitation Sector (DWSS), which will make it possible to apply specific tariffs, these companies will concretize the interdependencies between the water and sanitation activities. Their consolidation will offer certain benefits in terms of integrated management, harmonization of actions and common tasks and use of resources, cost reduction and integration of the private sector;

● The promotion of delegated management of drinking water and sanitation in rural or village areas.

The delegated managers will manage the networks (production, directly or by delegation to a private operator under contract, including leasing.)

● The creation of a National Fund for the Development of Water and Sanitation (FNDIEA).

To meet its objectives, the new Water Code redefined the roles of the current General Directorate of Energy, Mines and Water(Direction Générale de l’Energie, des Mines et de l’Eau, DGEME) enabling it to delegate the regulation of the water sector, i.e. water supply and sanitation, nationally (General Directorate of Water and Sanitation, Direction Générale de l’Eau et de l’Assainissement, DGEA) and regionally on each island (Regional

77

Directorate of Water and Sanitation, Direction Régionale de l’Eau et de l’Assainissement, DREA). The removal of the Energy Sector from its purview will leave the DGEA with a more focused and enhanced role.

The DGEA supports Regional Directorates of Water and Sanitation (DREA), responsible for regulating the water sector on each island and assisting the communes in their roles as project owners.

At the local level, Water User Associations (WUAs) will continue to represent the interests of the users. Because the WUAs had limited capacities to maintain and operate the equipment, the communes will be responsible for generating Public Private Partnerships with organizations (e.g., NGOs, CSOs) that will take on the role of the utility commissions. These commissions will be technically competent and established via mandate.

The drinking water and sanitation sector will be financed by allocating funds and by adopting a sustainable and socio-economically fair pricing scheme that covers the cost of exploitation, maintenance, and renewal of the infrastructure. Further, the specific needs of the rural populations will be considered, and the islands’ water resources will be further developed and protected.79

Figure 3132: Schematic of the institutional frameworks related to reform of the drinking water and sanitation sector (DWSS)

Institutions involved with water resources

At the national level, the Superior Council for Hydraulic Resources (Conseil Supérieur des Ressources Hydrauliques), CSRH, (i) defines the principles of national hydraulic policy; (iI) formulates plans and

79 Etude techniques du cadre institutionnel et de programme national d’AEPA, Mars 201378

programmes for the development and utilization of water; and (iii) drafts legislation and decrees on water management.

The General Directorate for Water and Sanitation (Direction Générale de l’Eau et de l’Assainissement), DGEA, (i) designs, formulates, and executes DWSS policy; (ii) devises five-year plans for the DWSS sector; (iii) identifies DWSS projects and drafts funding requests; (iv) provides technical assistance to the DREA for water monitoring and publication as well as for supervision of studies and works; (v) develops DWSS-related handbooks and tools; and (vi) sets up delegate-management contracts for DWSS systems.

The Water Sector Regulator (i) coordinates between the water utilities; (ii) implements water management regulations; (iii) publishes evaluations of water utilities and tariffs; (iv) implements the water decentralization procedure, delegates water management, and aggregates DWSS maintenance operators; and (v) reviews water management legislation and decrees.

The General Commissioner for Planning monitors the operation of the DWSS sector using indicators.

At the regional level, the Regional Directorates of Water and Sanitation (Direction Régionale de l’Eau et de l’Assainissement), DREA, (i) contribute to and follows the formulation of IWRM and PAUE master plans; (ii) identify extension and rehabilitation projects in cooperation with the villages and the DGEA; (iii) organize awareness days in collaboration with the villages; (iv) assist public and private operators in procurement and contractualization; (v) participate in national meetings (e.g. to define DWSS indicators); (vi) monitor and periodically inventory water resources; (vii) set up legally established protection perimeters; and (viii) carry out groundwater prospecting studies.

The Sectorial Commission for Hydraulic Resources (i) examines water plans and water use; and (ii) monitors the state of hydraulic resources and carries out various programmes.

At the local level, the Water User Associations, WUAs, (Comité de Gestion d’Eau, CGE; Association des Usagers d’Eau, AUE) will have a water network monitoring role by (i) representing the interests of the beneficiaries; (ii) reporting any signs of malfunction to the regulator; (iii) participating in decisions pertaining to DWSS infrastructure rehabilitation.

The Water Management Committees (Union des Comité d’Eau, UCE), WMCs, (i) support the DREA in data collection; (ii) and provide technical and accounting support to the delegated authorities and the delegated managers.

The villages take on the role of delegated authorities, becoming both owner of and responsible for the infrastructure. They bind themselves to a delegated manager, either in a PPP or via a leasing contract, who is charged with managing the DWSS infrastructure.

The profile of the delegated manager in charge of managing the DWSS systems depends on the complexity of networks to manage, and can range from micro companies, NGOs, WUAs, or others.

Rationale and best practice

Restructuring the government bodies involved with DWSS improves coordination of water resources management and sanitation. The current institutional reform is based on the experience of many African countries with similar socioeconomic contexts and policies, such as Cape Verde, Mali, Burkina Faso,

79

Mauritania, Chad, Niger and Cameroon, but in doing so it largely ignores the specific water challenges of small island developing states, including: limited fragile water resources, rapid response times to climatic extremes, intense land pressures and soil erosion, encroachment onto marginal land, high costs of transaction and service delivery. In doing so the Code addresses ‘business as usual’ and fails to consider water supply provision beyond normal operation conditions.

The guideline established by the new legislation aims to professionalize community management systems, recognizing that the community-management by Water User Associations currently in place has failed to deliver sustainable operation and maintenance, transparency, and consistent and fair tariffs. (See Section 4.2.2)

Professional management of water supply and sanitation systems will encourage operators to ensure the performance and sustainability of the installed infrastructure. This will be achieved using delegated management, an approach first introduced in the 1990s. To be successful, delegated management must go hand in hand with the transfer of skills to local communities in a process of decentralization. Delegated management centers on a contractual framework between four local actors: the delegating authority, the regulator, the delegated manager and a technical and financial support agent.

The delegating authority is both owner of and responsible for the infrastructure, and is required to designate a delegated manager, either in a PPP or via a leasing contract, who is charged with managing the DWSS infrastructure.

The profile of the delegated manager in charge of managing the DWSS systems depends on the complexity of networks to manage, and can range from micro companies, NGOs, WUAs, or others.

The regulatory authority is provided by the Regional Directorate of Water and Sanitation, which will ensure the validity of contracts, dispute arbitration, perform risk detection and on the good advice of stakeholders, it will apply appropriate mitigation measures and monitor performance indicators.

The technical and financial support agent (STEFI) provides technical and accounting assistance, auditing and consulting to delegated authorities and delegated managers.

In summary, the institutional reforms undertaken by the Union of Comoros, are designed to transform the management of water supply and sanitation systems, to improve coordination mechanisms for actors involved in managing water resources and to update the water pricing mechanisms, addressing concerns of the authorities on current shortcomings and malfunctions. The first step of this reform resulted in the formulation and adoption of the new Water Code. It was also accompanied by several draft decrees establishing the principles and modalities in line with the decentralization of water committees and associations as well as the development and formalization of IWRM committees.

However, it must be noted that the current institutional reform process does not address issues related to climate change.

The implementation of this on-going reform process provides a unique opportunity to mainstream climate resilience and specifically climate risk reduction into the national, regional and local authorities to establish a climate resilient DWSS system. Those tasked with supporting and implementing water supply must be provided with capacity reinforcement to effectively implement, manage and monitor adaptation measures.

80

Actors at all levels, national, island or regional and local, must be trained to integrate climate change risks into their planning and to disseminate good practices on pricing and regulation of standards that take into account the reality of the effects of climate change on water resources.

Parties involved with water resources

(I) Regional Directorate for Energy, Mines and Water Resources DREMRE,

(Ii) Directorate of Environment Anjouan DEA,

(Iii) Regional Meteorology Department Anjouan DRMA,

(Iv) Anjouan Regional Health Authority DRSA,

(V) Union of Water Committees of Anjouan UCEA,

(Vi) Association of water users AUE

81

SYNERGIES AND COMPLEMENTARITIES OF THE PROGRAMME WITH OTHER PROJECTS / PROGRAMMES

3.1 Overview of past and on-going projects

The Government of Comoros and the international community have invested approximately USD 50 million for current and future projects that concern water and climate.

3.1.1 Water Management

The ACCE project, Adapting Water Resource Management in Comoros to Increase Capacities to Cope with Climate Change, US$ 3.7 Million financed by GEF and supported by UNDP-UNEP, ended in December 2015. The ACCE project focused on increasing climate resilience of drinking and irrigation water supplies for all islands. It also stressed water management, reforestation, land use planning and small rural water mobilization (impluviums, cisterns and drip irrigation).

Under ACCE, specialized training was conducted for water management committees to set the stage for a water pricing system. The initiative was welcomed with real community involvement. The ACCE project also conducted capacity building training for local actors (UCEA, UCEM) for better water and water infrastructure management. The project set up committees (twenty-eight members of the water management committees in Lingoni-Pomoni and Nioumakelé bas), eight of whom were trained on good community management techniques and practices. Of the twenty members of the water management committees in Mbatsé and Hoanai, four were trained in water management techniques and good practices. In order to integrate the watershed dimension, IWRM committees have been set up at both Lingoni-Pomoni and Hoani-Mbatsé levels. Awareness training on the shared aspects of water resources has been conducted, integrating climate change impact dimension.

In pilot areas, watershed committees were established and provided training on the shared uses of water resources in the context of increasing scarcity due to climate change. The ACCE project conducted training on collecting and analyzing and downscaling climate models and reinforced their capacities to acquire and install equipment for measuring hydrometeorological and agro-meteorological parameters. It has essentially provided the first steps in establishing an effective climate monitoring system. The ACCE project was only delivered in specific targeted areas, and was not national in outreach. These areas are not within the GCF project target areas.

The ACCE project failed to mainstream climate resilience into the national bodies, focusing instead on state agencies and water service providers and hence failed to address the institutionalization of climate resilience and its necessary technical and financial resources into sector strategic planning and annual work programmes and budgeting. The national aspect of the project was given to the PEAPA project to develop the draft Water Code, which then neglected to include climate change within the future legislation.

Key additional lessons learned to this project were identified by the terminal evaluation of this project included:

1. Ensure a well developed operations and maintenance plan is created to secure sustainability of the infrastructure constructed, including identification of roles and responsibilities.

82

2. Necessity for inclusion of flow meters within the distribution system to capture long term usage to support the implementation of a tariff structure and detection of leaks to quantify lost water.

The Water Provision and Sanitation Project PEAPA project financed by the African Development Bank (US$ 10 Million)has supported regulatory reform for the Water Code. It suggested the integration of IWRM and drafted texts relating to the strengthening of the capacities of the local actors of the water management for a sustainable management of the hydraulic infrastructures in order better to manage infrastructure. PEAPA also made major investments in water supply infrastructure such as intakes and pre-treatment facilities.

The US$ 5 Million GECEAU project Support to public management of water in a pilot zone in Grande Comore, funded by AFD, is also investing in water mobilization infrastructure and has implemented a pilot project on water management. The project is developing boreholes, rehabilitating the water distribution network and creating an impluvium on Grande Comore.

Previously, AFD implemented similar water distribution projects on Anjouan and Moheli, where reservoirs, treatment stations and public fountains were constructed.80 AFD’s SIMA project also implemented a pilot project on water tariffs.

3.1.2 IWRM

Under ACCE, training and supervision of the communities for reforestation included:

● The creation of eight land management clusters at the project intervention sites to support the

implementation of the sustainable land management plan;

● Training of one hundred and twenty-five farmers on the project intervention sites in sustainable and

resilient agricultural land management techniques.The ACCE project also piloted reforestation activities in order to improve water basin management and prevent soil erosion. This included raising awareness of community members of the benefits associated with reforestation activities (and conversely, the costs associated with deforestation).

The Regional Integrated Water Resources and Wastewater Management Project (IWRM or GIRE) in Atlantic and Indian Ocean SIDS project (UNDP – UNEP) has implemented a watershed and wastewater management programme in the Mutsamudu River Basin of Anjouan. GIRE plans to reduce soil and water pollution and reduce the amount of water-borne diseases. The Anjouan Water User Association (UCEA) is being supported to improve water management, e.g. by setting water tariffs to cover the costs of water production and transmission. Awareness campaigns are being carried out to encourage upstream users and farmers to modify their practices to reduce pollution and sedimentation while increasing infiltration. GIRE has also installed a network of hydro-meteorological stations as well as flow and sediment measurement stations. The project concludes in March 2018.

This project has made important progress on establishment of a watershed committee and water resources management committees in pilot municipalities and their training in IWRM under the GIRE project. This

80 AEP (Adduction en Eau Potable) Sima and Domoni (Anjouan) and AEP Djandro (Moheli)83

project has the potential to be national in scope building from the participatory approach, and has valuable lessons in terms of the importance of stakeholder engagement.

3.1.3 Drinking water supply

The ACCE project led to the reconstruction of the 7 km water main from the capital Moroni to the TP5 well to a 2000 m3 water reservoir and associated drainage works. A total of 14,000 linear meters of HDPE pipe were installed as well as a pressure chlorination unit and a water resource monitoring device.

In Lingoni and Pomoni, within an ecological catchment at 530 m altitude on the Lingoni River, a 1.4 km main line was constructed as well as two sand-gravel water filters. Reinforced concrete tanks were also built, 57 born fountains were installed and a 7 ha irrigation network in Pomoni was put in place.

In Mbatsé and Hoani in the center of Mohéli Island, a main was rehabilitated, two sand-gravel filters were installed, a 400m3 reinforced concrete storage tank and 35 service fountains were installed and 20 hydrants in Hoani were rehabilitated. This infrastructure is in good condition due to improving the technical capacities at MamWe. The catchment of the Hoani River was also rehabilitated, in alignment with the precepts of IWRM.

Table 13: Table of concrete activity after the ACCE project.

The construction and rehabilitation of water infrastructure undertaken by the ACCE project were accompanied by a capacity building component to enable the sustainability of works after the project lifetime. Comorian technicians (e.g. Ma-Mwe staff) were trained under the supervision of international experts in the O&M of the rehabilitated/constructed water supply infrastructure. Furthermore, under the supervision of trained technicians, management committees consisting of community members, at least half of whom are women, were set up and trained thereafter to facilitate long-term maintenance.

Additional water infrastructure investments have been made by the World Bank under their FADC grant. This grant provided water supply infrastructure after the flood of 2011 / 2012 devastated much of the water

84

distribution network. However, infrastructure foundations are eroding due to flooding associated with climate change.

Other ad-hoc, uncoordinated water infrastructure projects are being implemented in some localities. Most of these are financed to a large extent by AFD under the Water Management Support Program Comoros (PAGEC) and by the EU through Water Programs for developing countries. On Mohéli, one such project, financed by the AFD, is rehabilitating the water network in the region of Wanani. On Anjouan, major works are planned for the complete renovation of the network and the construction of a reservoir by 2013 in the region of Sima, with AFD funding (US$ 4 Million). The European Union is also financing (US$ 6 Million) a project on Anjouan in the region of Domoni, as part of an effort to build a new catchment reservoir and renew the entire network. On Grande Comore, AFD is intervening in Mitsamiouli to strengthen the production capacity and the distribution network. The European Union also intervened in the Oichili region (US$ 1.5 Million) as part of a water supply program. The total financial implementation from 2003 to 2011 of the water supply projects carried out in Comoros is estimated at 2.6 billion FC (Commissariat General au Plan, Service des Programs d'Investissements Publics).

However with the exception of the ACCE project none are explicitly addressing climate risks in their objectives nor integrating climate risk reduction into the project delivery.

3.1.4 Climate Change Resilience

Relative to the capacities of the National Agency of Civil Aviation and Meteorology (Agence Nationale de l'Aviation Civile et de la Météorologie), ANACM, the ACCE project conducted training on collecting, analyzing and downscaling climate models and reinforced their capacities to acquire and install equipment for measuring hydrometeorological and agro-meteorological parameters. This enabled the ANACM to carry out activities related to weather and climatological information and forecasts and the evolution of the climate system necessary to meet the needs of users at national level and to ensure the international exchange of data in accordance with ratified agreements. The ACCE project took the first steps in establishing an effective climate monitoring system. The Climate Information Network was furthermore strengthened by the digitization of written climate data records between 1928 to 2000 (and some in unusable microfilm format).

Two climate change-related projects have also set the framework for climate change adaptation in the Comoros. The CRCCA project, Enhancing adaptive capacity for increased resilience to climate change in the agriculture sector in the Union of the Comoros (UNDP, LDCF) is building capacities to reduce the vulnerability of agricultural systems to climate change on all islands. The project includes support to agricultural extension and planning, the development of agro-climate services, and installing climate data collection infrastructure.

The CRCCA project recruited an Agro Meteorological Advisor (CAM) to support the interpretation and use of forecasting and information bulletins on climate change. This advisor supports the ANACM for the development of weather and agro-meteorological products to be disseminated to the different target groups (National Directorate of Agricultural and Livestock Strategies, Production Commissariats, CRDE, farmers, private sector, etc. ...).

In capacity building, the CAM supported the ANACM in the development of a comprehensive training plan for meteorological services and specific to the agro-meteorological service. This plan includes both training provided by the CAM and short or long-term training courses abroad. The project financed the training of two ANACM agents as agro-meteorological engineers at AGRHYMET (NIGER).

85

Similarly, the GCCA European Commission-funded project is strengthening the resilience of Comoros to climate change through climate change data management (using satellite and ground data in GIS systems) and dissemination as well as the integration of climate change into development strategies. The GCCA project will also implement local pilot projects related to water and sanitation, land use, agriculture and disaster risk management.

These climate change projects focus predominantly on the agricultural sector and provide some strengthening of key line ministries, however apart from at pilot scale they do not directly engage the water sector.

3.1.5 Gender integration

The ACCE project took gender into account when identifying organizations working in the field of water resources management. The capacity-building sessions of the beneficiary communities also take into account gender equality, with women making up a quarter of the forty-eight people trained on techniques and good practices of community water management. The project also set up Water Management Committees and land management groups of the project's intervention sites, which favor the participation of women.

3.2 Integration of best practices and lessons learned from implemented and on-going projects

3.2.1 Comoros project lessons

The ACCE project new agro-meteorological stations enabled ANACM to develop national weather reports for the first time in the country. Agricultural irrigation practices have been replicated and other donors have scaled-up efforts brought about by this project (e.g. AFD). The pilot sites have demonstrated improved food security and water supply within the sites themselves, serving as showcases for the rest of the country.

From the review of the terminal evaluation of the project key issues identified and lessons learned included:

1.However there has been little consideration of the vulnerability of the water resources and water supply sector to climate change risks, except at the pilot scale.

3.2.2 Global SIDS best practise

Recent SIDS specific Resilient WASH guidance developed in the Pacific Region by UNICEF provides a useful checklist on global best practice in SIDS.

Water supply side approaches include increasing access to drought water supply through increased abstraction, as well as increasing water storage to allow for dry season shortfalls, system storm outages and flexibility to use the water supply infrastructure from multiple sources to supply multiple supply zones. This flexibility includes the opportunity to access different water sources and resources at different times, i.e. to have multiple resource schemes i.e. available to exploit groundwater and surface water.

Water demand side approaches to reduce and/or suppress water demand, including leakage reduction, water conservation awareness campaigns, and tariff structures that penalize increasing usage.

86

In addition, it is more recently (and not so widely) recognized that climate resilience requires an understanding of the water resources vulnerability to climate extremes, including likelihood of low stream flows, saline intrusion of groundwater, reducing borehole yields, and increasing raw water turbidity during and after storm events – often with higher pollution levels. To manage these issues requires investigation of the water resources to understand them and then monitor their condition before and during climatic extremes. The IPCC itself47 recognizes this as an under-appreciated issue.

Hazard-based (i.e. avoiding or reducing exposure to the hazard e.g. flood flow), vulnerability-based (i.e. protecting the asset e.g. stream intake), adaptive-capacity (e.g. forecasting and utility preparedness) and policy-based CCA approaches should all be contributing to reducing risk. This includes adaptive management and water resources and watershed approaches, recognizing insufficient data exists for scenario-based approaches and that water supply infrastructure improvements alone will not resolve water shortages.

In summary, it is clear from the above that combining water supply side and water demand side improvements, investing in water resources management, adopting policy, institutional and technical scale approaches, including watershed adaptation, whilst building adaptation capacity at national (e.g. meteorological), institutional (e.g. infrastructure resilient planning) and community levels (e.g. rationing and agricultural water use efficiency) provides a coherent strategy to minimizing climate risks to the water sector.

The Pacific Region is arguably more cohesive as a SIDS region than the Indian Ocean, and as such develops regional approaches to addressing some of these knowledge and capacity shortfalls. UNICEF Pacific commissioned a WASH Resilience Policy Review81 of 5 Pacific SIDS in 2015. This serves as a useful synopsis of current and best practice in 3 LDC SIDS in the region – countries with very similar challenges to Comoros – another LDC SIDS.

This work recognized the limited technical, institutional and financial barriers to sustaining climate resilient WASH in these countries, and focused on identifying optimum approaches to assessing and reducing water sector climate risks in these data scarce environments further restricted by little adaptation capacity. The work developed a strategic overarching approach known as Drinking Water Safety and Security Planning (DWSSP), using a risk-based methodology to prioritise the deployment of scarce technical, management and financial resources to address the most significant risks.

This approach is an adaptive management approach, which includes IWRM when expanded to include the catchment areas.

3.3 Gaps in service and coverage of past and on-going projects

Despite the considerable efforts of the non-climate specific water supply programmes focusing on broader service provider institutional strengthening, infrastructure upgrades, cost recovery, and wider watershed management, and the strategic vision of a single project focusing on climate resilience in the water sector correctly exploring water resources monitoring, watershed and land use management as well as infrastructure resilience upgrades and climate forecasting, it is evident the water sector currently does not systematically integrate climate risk reduction into water supply provision and as such the sector remains highly vulnerable to climate change risks.

The gap analysis highlights both the inherent vulnerability to climate variability, due to the fundamental nature of the small island context – small land masses, with little natural freshwater storage, resources, which

81 GWP Consultants, 2016. Pacific WASH Climate Resilience Review. UNICEF Pacific.

87

respond rapidly to increases and decreases in rainfall and the increasing severity of the climate change impacts to come.

It is clear from the on-going and completed baseline of sectoral and climate change projects completed to date that there has been relatively little support to the water sector in climate adaptation beyond the pilot scale.

Existing and forecast hydrological variability based on a range of climate change scenarios and its impact on water resources and water supply infrastructure has received almost no attention. There has been no national scale effort on water resources monitoring and no climate focused support to national agencies, policies or legislation.

Water conservation and water loss reduction within the reticulated water supply schemes has received no attention, despite these being obvious demand side climate change adaptation strategies to reduce water shortages.

Perhaps of greatest concern, the fundamental and unavoidable issue of limited and fragile freshwater resources during periods of rainfall variability is not addressed in any way. Whilst currently this issue does not prevent year round water supply from being made available, this will become a critical data shortage with the increase in drought days, reduced aquifer recharge and increased erosion of watersheds.

This is particularly important with the predicted climate change impact of rainwater harvesting collapsing during future droughts resulting in greater demand for public water supply from groundwater when groundwater resources are under greatest pressure. This double-whammy means that climate change impacts necessitate the absolute need for i) assessing and understanding future drought yields from groundwater; and ii) maximizing the contribution of improved watershed management to increasing water retention and thereby increasing groundwater recharge and stream baseflows as well as reducing flood flow peaks and erosion. These two approaches will support maximum potable water resources availability during climatic extremes.

The increasing population growth rate (2.4%)82 and consequential future increases in water demand will obviously increase the number of people at risk of climate vulnerability. Water resources are abundant during periods of non-climatic extremes – rainwater harvesting works well in Grand Comore except during extreme drought periods, and average stream flows in Anjouan and Moheli exceed predicted future demand by usually at least two orders of magnitude83. The critical issue is potable water availability in times of droughts and floods.

What is clearly absent from the water sector interventions, be they climate focused or not, is a lack of consideration of climate impacts driven by an assessment of risks and how to reduce these risks. This is all the more important in Comoros because the limited and therefore inadequate levels of human and financial resources means risk reduction assessment needs to be mainstreamed so as to prioritize climate resilience efforts to focus precious human and financial resources into those areas which can have optimum benefit.

82 http://hdr.undp.org/en/data

83 Feasibility Study Section 4.4.388

BARRIERS TO ACHIEVING CLIMATE RESILIENCE AND ADAPTATION OPTIONS

4.1 Key barriers to achieving climate resilient water supplies

Current vulnerabilities to climate change are exacerbated by existing technical, financial and operational barriers in Comoros. The barriers include the following:

Limited technical capacity in water supply climate risk security planning, design and operation

Present-day water infrastructure in the Comoros is unlikely to be able to ensure improved supply and quality of water resources to Comorian communities under climate change conditions. Lack of know-how in designing, constructing and operating water networks, particularly in the context of climate change is one of the major gaps in expertise/training capacities.

At present, only a limited amount of hydrological background information, climate change research and climate change risk information is available for the Comoros and these matters are still poorly understood in the country. Whilst the government understands that climate change is a major development issue concerning the country, the existing information base on which the government can make adaptation decisions is limited.

Capacity gaps in terms of effective water resources computation, climate risk assessment and preparedness exist at all levels in government and non-government sectors.

Additionally, water resource management is not undertaken in keeping with international standards, which also prevents the adequate supply and quality of water resources.

The NAPA and INC have provided first approximations, but these are computed from a very limited database. More rigorous and robust modelling exercises are needed to further specify the climate change risk to water supply and quality throughout the country.

Meteorological equipment is inadequate and lacking in order to collect the appropriate data. To date, a comprehensive assessment of existing water resources in the Comoros has not been undertaken. Staff within ANACM are not adequately equipped or trained to communicate decision-making support information to the relevant ministries and departments (e.g. Ma-Mwe, DNEWR). This prevents the realization of a hydrological monitoring network in the Comoros.

Limited Knowledge and Data to Identify Climate Risks and Develop Adaptation Responses

Scarcity of baseline data hampers decision makers’ ability to assess the safe yield of the existing water resources, and thus to plan for future demand and make informed policy changes in water resource management. For example, using the safe yield, people will be aware of how much groundwater can be safely extracted without resulting in salinisation of limited resources.

At the national level, computation of the safe yield of water resources over the medium-term is prevented by a lack of national-level long-term projected changes in climatic parameters. The lack of baseline information is also a serious constraint on the government's ability to develop appropriate policies.

90

There is no current on-going monitoring of water resources and water supply infrastructure performance and no monitoring systems in place to allow such monitoring to occur. This lack of knowledge has not been essential to operate the nation’s water supply to date, however it is now required in order to understand reliably the nation’s fragile water resources, their availability during climatic extremes, and their quality and vulnerability to future climate variability and plan their resilience.

The lack of climate forecasting in-country prevents early warning of future climate impacts, other than by evaluating the antecedent conditions experienced in the country in previous hours, days and months. Monitoring requirements to assess climate risks requires even greater monitoring resources as the need for monitoring becomes time critical, especially for flood and erosion risks, but also for drought, as well as understanding how stressed the water resources become during climatic extremes.

Consequently, it is not currently possible to identify climate hazards (beyond the generic), evaluate priorities, determine risk reduction measures and implement adaptation measures to increase water resources and water supply resilience.

Lack of appropriate climate risk reduction legislation/policies in the water sector

The preferred solution regarding the improved legal framework is hindered by a lack of expertise regarding effective legislation/policy revision and the finance to undertake the necessary research and revision. Additionally, data regarding climate change risks and the benefits of sustainable land management to make the case for altering policies/strategies/legislation are not readily available.

Overall, the Comoros lacks a clear and specific legal and policy framework to address climate change concerns.

Furthermore, the policies and legislation governing access to water and land are outdated and often conflicting. There is thus no regulation for encouraging enforcement of appropriate policies/strategies/legislation regarding water and land management and unsustainable activities are regularly undertaken (e.g. water resource pollution control regulations and related ordinances do not exist).

The policies and legislation governing access to water and land are outdated and often conflicting. There is also an absence of regulatory framework and policy instruments at the country and island level (i.e. which define the mandates, missions, and responsibilities of the institutions between the Comoros government and the island entities involved in water management) in the water sector.

This creates a major bottleneck in the coordination of cross-sectoral policies and reduces inward investment.

Lack of integrated watershed management to deliver eco-system based climate adaptation

The function of watershed ecosystems as eco-system service providers is not adequately recognized in Comoros. Decades of watershed derogation have severely reduced watershed water retention, flood regulation, soil stabilization and water quality clarification processes as well as reduced food security through land degradation.

Without adopting integrated watershed management approaches, the climate change impacts will be magnified through the loss of these eco-system services, and infrastructure solutions will have to focus on resilience to highly vulnerable catchment responses to increasing extreme drought, flood and erosion.

91

Conversely by adopting integrated watershed management approaches, climate impacts on both water and food security can be addressed in a holistic approach, with improved farming practice increasing stream flows which then support greater irrigation.

A lack of technical knowledge, watershed partnership, monitoring and characterisation, as well as long term investment and sympathetic water exploitation need to be overcome to protect and benefit from the watershed eco-systems.

Inadequate Stakeholder Coordination to Deliver Climate Resilience

Comoros has national, island and community (water user) governance arrangements in place. The autonomous island/state level specific to Comoros introduces an additional level of institutional mandates and therefore complexity and fragmentation of water resource and water supply mandates, roles and responsibilities, including the planning and budgeting of annual work programmes, than is usually observed.

The new Water Code legislation articulates a more effective and efficient institutional arrangement for delivering more reliable water supplies, but it does not consider climate change risks to water supplies.

There is no formal governance mechanism for water resources and watershed management at the island scale, although the introduction of IWRM to the regional water directorates by the GIRE project have created an entry point for improved coordination. A national IWRM Plan was validated in August 2017, but has yet to be enacted. With periods of climatic extremes this lack of IWRM to date has not been a critical barrier to water security. However the impact of climate change on water resources necessitates the use of watershed management to both prevent water quality derogation and optimizes water quantity availability – through water retention within the catchment. IWRM therefore becomes an essential climate change strategy in countries with fragile and finite water resources. In addition as climate risk reduction is arguably the most important IWRM issue with which to promote IWRM, using climate resilience to secure political and community support to IWRM is highly effective. Climate risk reduction through IWRM can therefore be used to secure wider commitments to improving non-climate related drinking water quality risk reduction to the water sector e.g. pollution.

Climate risks also introduce a much greater requirement for coordination, cooperation and collaboration between agencies and stakeholders, as they require data, decision-making and actions (e.g. preparedness and response) to transfer between organisations more quickly than managing water resources and water supply in normal operating conditions. Whilst the recent Water Code reforms accommodate the requirement for improved coordination, this does not extend to the level required to achieve effective climate risk reduction.

Limited Financial Resources to Deliver Climate Resilience

Comoros has limited financial resources that prevent it from adequately addressing climate change adaptation needs. Classified as a Least Developed Country by the UN System, the Comoros ranks 169 on the Human Development Index (out of 187 countries), with US$ 840 GNI per capita, and 46% of the population living in absolute poverty with less than US$ 1.25 per day. Anjouan and Mohéli are the poorest islands. 84 A large proportion of the population relies on remittances from the Comorian diaspora (mainly in France and Mayotte), which was estimated to have sent in US$ 35.4 million in 2004.85


85 UNEP project document92

Additionally, constraints in financial resources have led to limited support to train and hire qualified technical personnel. The select technical personnel who are trained often leave ministries to join international NGOs or leave the Comoros for more lucrative positions abroad. Consequently, the government requires more financial support in all states to train multiple personnel to manage land and water resources effectively. Current investments by donors (described in the baseline section) need to be augmented across Comoros at a large scale in order to ensure that state and federal governments as well as Community Based Organizations have the capacities to enact measures supporting water security.

In the PEAPA report, the African development bank highlighted the vital importance of sustainable water service provider financing, proposing the creation of regulatory body, the National Regulatory Authority for Water and Sanitation (Instance Nationale de Régulation de l’Eau et de l’assainissement, INREA) to oversee water pricing among other activities.86 Water tariffs would be periodically revised by the regulatory authority to reflect investments and exploitation levels.

A lack of financial resources is seen as a critical barrier preventing climate resilient water supplies, with a lack of investment in both capital expenditure and recurrent operation and maintenance budgets to allow mainstreaming of climate risk reduction into water supply provision. A tariff system should be introduced that enables the sustained commitment of resources to continue to allow the climate risks to be avoided, reduced or treated by implementing water security response plans to climatic forecasts and warnings.

Based on a recent willingness-to-pay poll conducted by the AFDB under the PEAPA project, water tariffs will be charged based on the volume of water used and subsidized in cases where populations are too poor to pay for services.

The Government of Comoros recognises however that collection of tariffs will be difficult until the population starts to receive improved water quality. The Government of Comoros therefore has committed to co-funding the scheme operation & maintenance costs for the first 15 years, during which time water quality monitoring and drought water supply delivery will be demonstrated to the beneficiaries and tariffs introduced in a staged approach.

Water supply service providers are currently undergoing tariff reforms as part of the on-going water governance reforms mandated by the new water legislation (Water Code) to improve the sustainability of the water sector. As previously discussed, the reform including widespread tariff introduction is at a very early stage and affordability surveys have not been conducted; as a result, the timing, magnitude and reliability of any revenues from water tariffs are extremely hard to predict.

In addition, the issue of appropriate tariff setting is only identified within the new Water Code in terms of normal operating conditions. It is not recognized with respect to the level of additional investment required to deliver resilience to climate impacts – which require much greater investment in risk reduction and preparedness planning (CAPEX) as well as risk reduction operation & maintenance (OPEX).

Water resources monitoring and watershed management however appear to receive no current budgetary support at all, given there is no national hydrological monitoring network, no clear understanding of the nation’s water resources, and little watershed management. To date the lack of a hydrological monitoring network and protected watersheds have not impacted water supply provision, however climate change

86 African Development Bank, Strategy and Programme of PEAPA in the Comoros93

rainfall variability necessitates water resources and watershed management as critical strategies to protecting and increasing water resources availability during climatic extremes in SIDS.

4.2 Recommended Climate Change Adaptation Options

The following climate change adaptation options are recommended based upon the water resources assessment and other technical studies. These are separated below into two groups of national scale actions and island scale infrastructure actions.

4.2.1 National Water Sector Climate Change Resilience Actions

The following recommended actions are considered to be national in scope and coverage.

Climate Change Adaptation mainstreaming into Water Governance

Comorian communities, the governments of each autonomous island and the national government presently lack the technical capacity, management capacity, physical resources and financial resources to adapt their water resources and water supply management to worsening climatic conditions.

Climate-risk informed professional planning and management of the water resources, watersheds and water supply and sanitation systems is needed to ensure their long-term sustainability and performance and protect both the existing and future more climate-resilient infrastructure to be installed.

As water is a cross-sectoral issue that is embedded in the mandate of various Departments (including the Direction of Energy (DGEME), Environment (DGEF), the Ministries of Transport (Meteorology Department) and Health), the GCF project will support improved inter-sectoral coordination and the integration of climate change risks into the framework of institutional reforms on decentralizing water management brought about by the newly revised Water Code and the recent introduction of national IWRM governance approaches.

A National Water Security Plan will also be drafted and updates to the Water Code will also be made in order to detail the requirements and responsibilities for climate-informed i) protection of sources, ii) operating & maintenance procedures during extreme dry / wet periods and iii) water quality standards. Best practices will be detailed that address intense rainfall events, prolonged drought and saltwater intrusion.

The project should also establish, standardize and apply evaluation criteria for socially-sensitive water tariff pricing mechanisms to ensure prices reflect the climate resilience upgrades to sustain production, storage and treatment during periods of climatic extremes. Such costs are required to be covered in order to enable the Water Management Committees to have the capacities and resources to prepare for existing and predicted climate change impacts – the costs of managing water resources in extreme conditions are greater than managing in routine operating conditions.

Socially-sensitive billing rates for water tariffs will be standardized so that they can cover locality-specific production and distribution costs in the face of climate extremes, being able to supply sufficient, good quality water during and following dry periods and intense rainfall events. The new Water Management Committees will be created as contracted service providers to the communes. This approach has been successful in managing water resources and in supporting payment collection mechanisms in certain rural districts (e.g., SOGEM in Moheli).

94

Drinking water management structures will be strengthened in rural and urban areas for both state and non – state run agencies. This includes training for the water agency / organization on climate change impacts and risk reduction approaches on water resources, water quality, water hygiene, water infrastructure O&M and water tariff rates.

Awareness-raising on climate change risk reduction will be provided on water laws, water quality issues and water production and supply costs relative to water tariff rates.

Water Resources and Watershed Investigation & Monitoring, Climate Forecasting & Behavioral Change Adaptation

A lack of water resources information prevents informed water resources planning, water resources climate vulnerability assessments and robust targeting of resilient water resources to support dry season water supplies, as well as prevents protection of water resources from deterioration through avoiding increasing exposure to climate-related risks – such as storm floods.

The country requires a national water resources monitoring network on rainfall, streams and groundwater monitoring piezometers, some with real time telemetry to provide early climate event (storm) warnings as well as monitor longer term drought risk and support optimization of abstraction systems.

An island wide groundwater investigation programme is recommended for Grand Comore in advance of further infrastructure investment and rehabilitation. This should include up to 30 groundwater monitoring piezometer nests around the island. These should help define the 3 dimensional geometry of the basal freshwater lens up to 5km inland, and specifically explore the control on freshwater groundwater occurrence – believed to be related to proximity to storm flood water flow routes and inland of coastal cinder cones. The work should result in defined climate resilient dry season sustainable yields as well as climate influenced flood routes off the mountains.

Monthly, quarterly and annual manual and automated groundwater level, salinity and selected other parameter monitoring is required at all monitoring and production locations.

Island wide surface water groundwater investigation programmes are required on Anjouan and Moheli and are recommended in advance of further (post-project) infrastructure investment and rehabilitation. This should include up to 10 automated rainfall stations, 30 automated surface water flow and quality monitoring stations and 15 groundwater piezometer nests across both islands.

These should help define: storm peak and drought low flows in catchments, speed of peak flood flows and recession of the flows during the dry season; relationship between climate change increased rainfall, flow, turbidity and microbiological contamination; explore the control on freshwater groundwater occurrence – including high level perched springs, basal freshwater lenses and alluvial tract aquifers.

The work should result in defined dry season sustainable yields for stream intakes, variations in seasonal turbidity and microbiology concentrations, as well as defined flood routes and flow heights and velocities off the mountains, which will be used to establish climate risks and inform risk reduction approaches and actions.

The work should also identify future drilling targets for possible post-project production wells on these two islands.

95

To ensure climate resilient sustainability of the water resources, watersheds and water supply systems, user behavior change should be promoted with respect to protection and conservation of water resources, watersheds and services from climatic risks, including drought, floods and erosion.

Users will need to be informed about the link between water and climate change and the need for water conservation.

In order to do this in a timely manner and in response to evidence-based monitoring of increased climate change induced climate variability, long term and short term climate forecasting, and in particular rainfall forecasting is required to allow communities and organisations to initiative their climate resilience preparedness plans.

Forecasting and preparedness and response tools, guidelines and products will be need to be developed and tailored to support sector specific resilience adaptation management.

One of the critical approaches to adapting the water resources to climate change risks is behavioral change in the watershed themselves. The project should establish an integrated watershed management87 approach to improve ecosystem based adaptation services, most notably focussing on ensuring watershed planning and management supports and is consistent with climate resilient water and food security.

This requires first characterisation of the watersheds, then coordinated integrated planning and implementation of climate risk reduction watershed water and land management plans to reduce extreme hydrological pressures on watershed ecosystems and optimise land use to protect dry season water resources, and reduce flood flows and erosions rates.

As such initiatives will be multi-sectoral these too will require IWRM approaches at the watershed scale.

4.2.2 Recommended water supply climate resilience infrastructure actions on Grand Comore

The water resources assessment for Grand Comore has identified the following:

● Increasing household rainwater harvesting is constrained by the size of built properties and is

therefore unlikely to provide additional drought resilience;

● Communal rainwater harvesting briefly extends water supply during drought periods but is considered

to already be optimized with respect to available community buildings and therefore provides no additional resilience to future climate change extended droughts;

● Volcanic rainwater impluviums provide a valuable source of non-potable water, especially at the

higher altitudes where pumped groundwater cannot currently reach. Creating and rehabilitation of impluviums should be pursued by the project to increase food security during the climate change induced increasingly long and intense dry periods (+48 days);

87 Integrated watershed management is defined as “…the process of organizing and guiding land, water, and other natural resource use on a watershed to provide desired goods and services to people without affecting adversely soil and water resources. Embedded in the concept of integrated watershed management is the recognition of the interrelationships among land use, soil, and water, and the linkages between uplands and downstream areas.” Excerpt from: Kenneth N. Brooks. “Hydrology and the Management of Watersheds”.

96

● Groundwater is available around most of the island, is available year round and has the added

advantage (and cost saving) that it does not require substantial storage to support extended dry season water supply – resilient groundwater supplies should be a priority to address drought vulnerability of inland communities currently reliant on rainwater harvesting;

● However, groundwater knowledge is very limited and there is an urgent requirement for island wide

studies and routine year round monitoring – this will improve climate resilience siting of new wells, avoid saline wells being constructed, and allow forecasting of drought impact on groundwater;

● Knowledge of existing groundwater wells optimization in terms of design and pumping regimes is very

limited, with no quantified understanding of salinity risk to any of the wells. Existing wells needs to be carefully investigated to identify sustainable pumping rates during climate change extended dry periods;

● Existing wells need to be protected from climate change enhanced storm run-off contamination risks.

This requires Drinking Water Safety and Security Planning of each source. Assuming the reported borehole hourly pumping rates only operate for 12 hours per day, then the following water supply and demand balance exists in each project zone in Grand Comore:

Demand Demand Demand Source Source Source Balance % Difference Option

Zone Pop m3/d l/s lppd m3/hr m3/d l/s m3/d l/s

1 219660 11637 135 53 784 9408 109 -2,229 -24% 26 New Forage

2 43691 2185 25 50 65 780 9 -1,405 -180% 16 New Forage

3 15994 799 9 50 0 -799 9 New Forage

4 21053 1165 13 55 45 540 6 -625 -116% 7 New Forage

5 27242 1362 16 50 30 360 4 -1,002 -278% 12 New Forage

6 21742 1087.1 13 50 -1,087 13 Rainwater

Table 14: Table of water balance for Grand Comore

These water balances confirm that limited additional groundwater abstraction, by optimizing or improving existing wells and/or drilling additional boreholes, can provide extended dry season water supply to replace current dry season rainwater harvesting which is expected to fail in the future due to climate change.

Using non-potable impluvium rainwater in Zone 6 for irrigation allows use of existing freshwater supplies for potable water uses.

Rehabilitating/Optimising existing boreholes to Minimise Dry Season Salinity Risks

The work should target optimization of the existing production wells, by investigating drawdown, salinity, construction details, pumping rates and comparison with (as yet to be constructed – see national actions above) piezometers measuring the thickness and salinity of the freshwater lens. This will then inform

97

alterations to the well construction as well as pumping regime – thereby reducing risk of increasing salinity during climate change extended dry periods.

Subject to the findings of the individual borehole saline up-coning vulnerability climate change risk assessments, rehabilitation is proposed on the most used and most valuable wells – those in the area around Moroni.

Recommended actions in Zone 1 include the rehabilitation of the ONU4, TP1 and TP5 boreholes, including carrying out a pumping test and protecting the catchment area. This will include investigating their current structural integrity as well as optimizing the pumping regime.

The increasing reliance on groundwater to meet dry season water supply as well as the increase pollution risk associated with increasing storm flooding, necessitates improvements to their water treatment systems to ensure climate change resilience.

Recommended actions in Zone 2 include the rehabilitation of the ONU39 borehole, including carrying out downhole investigation, a pumping test to try to determine how best to reduce its salinity (currently 1500 mg/l) and protecting the catchment area.

Recommended actions in Zone 4 include potential deepening the ONU23 borehole (borehole base is currently reported as 70m AmSL), carrying out a pumping test to determine how best to reduce its salinity (currently 1700 mg/l) and protecting the catchment area. This action requires detailed land surveying, downhole investigation to confirm well depth and drilling of a nearby groundwater monitoring piezometer nest to confirm freshwater exists at greater depth.

ONU40 in Zone 5 will also undergo pumping test trials and inspections to improve its performance and reduce its pumped salinity (1000 mg/l). It is reported to have a drawdown of 0.60m at a pumping rate of 8 l/s (giving a specific capacity of 1,200m2/d). Again a nearby piezometer will be drilled to guide this testing.

Currently these wells are reported to produce up to 20M L/d (i.e. 230 litres per second or 7.3 M m3/year) to supply the population of Grand Comore. Their climate resilience is fundamental to the water security of the island.

New borehole in Hambou Djoumoipanga

A new well, Hambou Djoumoipanga, should be drilled for Zone 3 in the general vicinity of two existing boreholes (ONU9/ONU37) that already provide more than 1.88 M L/d (20 l/s) of moderately fresh water (see table below). The moderate salinity levels observed in in ONU9/ONU28 warrant equipping it with a microbiological water treatment system.

Name Latitude (dms)

Longitude (dms)

Location Discharge (L/d)

Depth(m)

Salinity (mg/L)

Cond.µS/cm

Exploitable

Onu 9 11°49'23" 43°17'10" Chouani 1,68 32.7 500 1400 yes

Onu 37

11°48'17" 43°16'44" Mitsoudjie 1,560 49.7 800 1600 yes

Table 15: Boreholes in in the vicinity of the new Hambou Djoumoipanga well (Zone 3)88

88 PAEPA, context hydrologique, 201398

A previous investigation had been carried out in the area, including field visits and a geological map review. 89 It revealed the presence of basaltic scoria surrounded by pyroclastic deposits at the locations of boreholes ONU9 and OnU37. The target zone is located where the aquifer is considered to be easily exploitable and at not less than 2 km distance from the coast. Groundwater monitoring piezometers should be installed in the area to finalise the production borehole drilling location. Proximity to storm run-off channels is considered to be favourable.

Pumping tests should be carried out in order to ensure sustanable use of the infrastructure, and the catchment area will be delimited to ensure protection. It is recommended a 300 to 450mm diameter borehole is constructed rather than a wide diameter open well.

Consideration should also be given to simple run-off water retention basins to promote aquifer infiltration inland of the borehole.

New borehole in Moroni Bambao Itsandra

A second new well should be drilled in Moroni Bambao Itsandra, in the vicinity of two existing wells (TP1 and TP5). This borehole, to be located near Vouvouni, includes a pumping test, protection area delineation and treatment system. It has a nominal target depth to be drilled of 50m depth.

Groundwater monitoring piezometers shouldl be installed in the area to finalise the production borehole drilling location and design. Proximity to storm run-off channels is considered to be favourable.

It is recommended a 300 to 450mm diameter borehole is constructed rather than a wide diameter open well. Multiple boreholes may be required if the required abstraction rate cannot be achieved.

New borehole in near Chezani

A new production borehole is proposed inland of ONU23 and west of the village of Chezani in Zone 4. At twice the distance from the sea as ONU23 it is expected the groundwater will be fresher. As above, production borehole drilling should only occur once the groundwater has been proven to be fresh using exploratory drilling and piezometer installation and monitoring.

New borehole near Koimbani Zone 5

A new production borehole is proposed west of the village of Koimbani in Zone 5. As above, production borehole drilling should only occur once the groundwater has been proven to be fresh using exploratory drilling and piezometer installation and monitoring.

Recommended increase in groundwater supply storage infrastructure

In order to minimize the risk of pumping saline water into the wells during climate change extended dry periods, it is necessary to avoid high and fluctuating instantaneous well pumping rates and allow the production wells to pump at as low a rate as possible throughout any 24 hour period.

This requires peak water demand to be met from service or peak flow tanks. These tanks allow the twice daily peak demand (typically 3-4 times that of average demand in the morning and evening) to be met without

89 Diagnostic approfondi de la ressource en eau pour l’approvisionnement des îles Comores, April 201699

requiring the wells to be pumped harder during these periods at these higher rates to meet immediate demand.

Service reservoir tanks are therefore proposed for Zones 1, 2, 3, 4 and 5. These are typically multiple 200 to 500m3 tanks, which drain under gravity to designated supply zone areas and which are intended to be able to hold 0.5 days of storage as a minimum (allowing overnight and during day tank refilling) and ideally hold 1 day and possibly 2 days of water demand in case of pump failure, water main damage, or power outage, all of which are especially common during cyclonic or tropical storms and associated floods.

Because water storage residency times could be 2 days or longer, the water will require simple treatment (chlorination).

Recommended expansion of irrigation water storage infrastructure

The impluvium irrigation daily water balance (2008-2016) analysis undertaken earlier confirms impluviums will provide greater extended dry season irrigation of cash crops, than currently achieved through ad hoc delivery of water from road tankers. The reliability of dry season water supply will clearly depend on the contributing impluvium catchment area, its storage volume as well as the irrigation area and crop type.

4 additional volcanic cones have been identified for conversion to impluviums in the central agricultural upland zone of Grand Comore, plus rehabilitation of a 5 th at Sangani (see Appendix 10 - Locations and existing and proposed infrastructure).

The earlier analysis presented showed Sangani can provide dry season irrigation for 14 hectares. Similar analyses have been undertaken for the other impluvium. The impluvium are to be connected via a pipe network to a series of micro-basins (each 50m3) allowing irrigation demand control and more equitable sharing of water resources, whilst also reducing leakage from the impluvium themselves.

The storage hydrographs for the other four impluvium are shown below. Clearly the irrigation demand is the critical use of the impluvium stored water and is controlled by irrigation area, crop type, planting timing and quality of farming practice. Irrigation demand per unit area is critical – farming efforts to reduce this e.g. crop selection or farming practice will have significant impact on retained water storage through the dry season.

A detailed analysis of these parameters is not given below, although examples for each impluvium are illustrated below as well as the possible irrigation areas, without improved farming practices.

● Construction of an impluvium in Hamalengo to irrigate 6 hectares

100

Figure 3233: Rainwater harvesting storage for the Hamaleno impluvium with effective rainfall set to 0.5l/m 2/d and soil holding capacity at 180 l/m2.

● Construction of an impluvium in Trodjou to irrigate 51 hectares

Figure 3334: Rainwater harvesting storage for the Trodjou impluvium with effective rainfall set to 0.5l/m2/d, soil holding capacity at 180 l/m2 and evapotranspiration 3.0.

● Construction of an impluvium in Hamtroni to irrigate 15 hectares

101

Figure 3435: Rainwater harvesting storage for the Hamtroni impluvium with effective rainfall set to 0.5l/m 2/d, soil holding capacity at 180 l/m2 and evapotranspiration 3.5.

● Rehabilitation of an existing impluvium in Sangani to irrigate 14 hectares

● Construction of an impluvium in Mberadjou to irrigate 50 hectares

Figure 3536: Rainwater harvesting storage for the Manvangani impluvium with effective rainfall set to 0.5l/m 2/d, soil holding capacity at 180 l/m2 and evapotranspiration 3.0.

102

As demonstrated earlier, larger areas can be irrigated when water efficient farming practices are utilised. The hydrograph below is for improved agricultural water capture efficiency (20%) and soil retention (30%) enabling the doubling of the irrigation area.

Figure 3637: Rainwater harvesting storage for the Hamaleno impluvium with effective rainfall set to 0.7l/m 2/d, soil holding capacity at 250 l/m2 and evapotranspiration 3.5.

These farming practice adaptation options include:

● increasing direct rainfall capture percentage by the crop - such as by planting crops within mini-bowl

depressions to encourage rainfall to move toward each crop root;

● mulching around crops to reduce evaporation and increase soil water retention; and

● reducing leakage to the sub-soil and deeper volcanic rock by reducing the below sub-soil permeability

by compaction and/or placement of a clay pan horizon. These are all best described as agricultural/farming water use efficiency (WUE) adaptation approaches and are critical to developing rural community adaptation level resilience capacity through WUE behavioral change informed by climate forecasting. This is recommended to be included in the project.

4.2.3 Recommended water supply climate resilience actions on Anjouan and Moheli

The water resources assessment of Anjouan and Moheil identified the following:

● Groundwater in Anjouan and Moheli provides a vital role in water supply on the island, primarily

through sustaining dry season low flows in springs and streams;.

● However there is very little understanding of the groundwater resource, with no detailed investigation

and no on-going monitoring of groundwater or surface water flows;103

● An island wide network of stream flow and quality monitoring is required, as well as a more detailed

programme of hydrogeological characterisation of the island to better understand the lateral extents and yields of the perched, alluvial and basal aquifers;

● Springs being exploited for year round supply need to be protected from storm event peak flows

which could damage the spring capture works and its associated conveyance infrastructure;

● All water sources need to undergo formal climate vulnerability and risk assessment as part of Drinking

Water Safety and Security Planning (DWSSP) which should inform their design, and later operation, maintenance and re-investment programmes as well as inform watershed management plans;

● The stream watersheds are small, steep and narrow with negligible natural storage and will therefore

respond rapidly to intense rainfall events. The catchments can be expected to therefore be susceptible to increasingly intense rainfall events which are likely to both damage and block surface water intakes;

● Maximising the capture of these stream low flows is essential to increasing resilience to increasingly

frequent and longer duration dry periods;

● There is no characterisation of stream flow or water on the island nor any operational flow and quality

monitoring. An island wide programme must be implemented at the first opportunity;

● It is important to guide detailed design new water intakes to be resilient and flexible so as to allow

capture of climate exaggerated low flows and be resilient to damaging flood flows. This should include low level intakes, ability to close intakes during high turbidity flows, intake over-topping arrangements, and access routes, pipelines and storage tanks located away from the flood flow corridors. This requires an assessment of flood risk zone mapping;

● Storage should be built into the gravity delivery systems to enable the intakes to be closed for short

periods during storm events – to prevent sediment ingress – and to continue to allow the supply of water during low flow periods;

● This requires an adaptation capacity at the operation and maintenance level of the water service

provider as well as a reliable and timely forecasting capacity for flood risk and drought risk; and

● Water treatment needs to be added to the water supply schemes. Turbidity of raw water is predicted

to increase and water quality decrease with increasingly common more intense rainfall events, resulting in normal drinking water quality deteriorating below that which the local populace has developed a level of resistance. Thus water treatment is required to overcome this climate change created decrease in raw water quality.

Maximising Stream Flow Capture

The islands of Anjouan and Moheli have abundant surface water natural drainage networks that have long been the main source of water for the population.

104

According to studies outlined in the PEAPA, exploitable surface water resources for drinking water supply on the island of Anjouan are estimated at 128,158,580 m3/year, compared to 228,543,945 m3/year total surface water resources. It should be noted, however, that the report also highlights the need to refine these estimates. The PEAPA report estimated surface water exploitation rates on Anjouan at 1.2%.

Exploitable surface water resources for drinking water on Mohéli are estimated at 41,386,003 m3/year, compared to 78,536,563 m3/year total surface water resources. Of these, only 1.9% were estimated as being exploited by the PEAPA report.

Such annual water balance figures are however misleading for small island developing states, whose catchments do not allow capture and storage of a high percentage of rainfall, and whose rainfall tends to arrive in intense short term events.

These catchments are small and steep and therefore suffer from both rapid responses to intense rainfall events which damage stream infrastructure and erode the watershed result in in high turbidity, but also have a lack of natural storage resulting in low flows in non-rainfall periods. The catchments are therefore inherently vulnerable to existing climate variability and any increase in this variability will only worsen matters.

A complete lack of on-going monitoring year round stream flow measurements on both islands means the understanding of how quickly peak flood flows are generated and low flows arrive is poorly defined, other than for preliminary studies in Mutsamudu and Daji on Anjouan. These studies confirm typical low flow periods in Oct-Dec and high flow periods in Jan-Mar. This confirms the very longest time lag between rainfall and stream response is 2-3 months with respect to the catchment draining, and almost immediate in terms of rapid storm event responses.

Monthly rainfall records confirm the 6 driest dry seasons in the last 55 years have all occurred since 2010. It therefore highly likely the lowest Oct-Dec flows have been observed in these rivers in the last 6 years. Spot measurements taken during this period confirm 20 captage to be receiving < 1 l/s during these periods.

Across the project zones in Anjouan and Moheli, the following observations are reported:

● Direct use of stream water – i.e. taking water from the stream using hand held containers, as well as

washing, is common place;

● Stream intakes have been damaged by the April 2012 floods and many are not repaired;

● Village constructed schemes have no filters and are frequently blocked and provide limited

clarification of turbid water;In summary, existing schemes are highly vulnerable to flood events, erosion and turbidity and poorly designed to capture low flows.

Increasing household access to resilient stream intake schemes capable of treating increasing turbid water and capturing low flows will increase the local populations resilience to climate change.

In order to do this, it is important the proposed new or upgraded schemes can provide water to the demand population year round.

May 2017 Stream Flow Field Measurements105

Instantaneous stream flow measurements were recorded by local UNDP consultant staff at areas of interest to the GCF project in Anjouan and Moheli in May 2017. Based upon the flow hydrograph data for Mutsamudu and Daji, such flow estimates would be expected to be neither peak flows nor low flows, but representing an average flow condition. These are tabulated below.

Table 16: Table of stream flow data for Mutsamudu and Daji.

The accuracy of the measurements and calculations is uncertain (red text denotes uncertainty), however they should provide a first order estimate of observed flow in the streams in mid-May 2017, a month when flows are dropping from their peak flows in March but are well above those expected in October.

Geographic Information System Digital Terrain Model Catchment Yield Estimation

In order to try and confirm the likely accuracy of these flow measurements and put them into context, a GIS based stream routing analysis was undertaken of the contributing watershed basin upstream of the given locations – or assumed locations based upon the GIS database available. The reliability of the locations is unclear as these are not all located in the main stream valley floors. Notwithstanding, this allowed the following catchment characteristics to be determined:

Table 17: Table of catchment characteristics from GIS data.

A water balance analysis was undertaken on the above sub-catchments using the following 3 monthly average rainfall, driest monthly rainfall, and other quartile rainfall totals, run-off coefficients and ground infiltration rates.

106

The rainfall monthly data set is for Moroni (1901-2015) but is considered relevant to catchments on the other two islands with rainfall approximately 2500mm/yr i.e. in the central highland region of each island.

Input parameter ValueAnnual rainfall (mm) 2500Infiltration (% rainfall) 10Runoff Coef 90Avg. rainfall of driest 3-month period (Sept.-Nov.) (mm/month) 52Avg. rainfall of driest month (September) 31Avg. rainfall Q2 (Apr. - Jun.)(mm/month) 149Avg. rainfaill wettest period Q1 (Jan. - Mar.) (mm/month) 248Avg. rainfall of wettest month (Jan) mm 295

Table 18: Dry Season Flow Estimation Input Parameters

The following stream flows have been estimated for the above proposed intake locations, assuming all rainfall generates run-off (i.e. run-off coefficient is 100%):

Table 19: Stream flow estimates for Anjouan and Moheli

Earlier work suggests aquifer recharge is likely to be 10% of rainfall. If the catchment run-off drains out completely then minimum natural low flows are more likely to reflect this groundwater contribution only. Whilst the groundwater catchment does not necessarily reflect the topographic watershed, in the absence of additional information, the upstream watershed area has been assumed to be the area contributing to baseflow. The following base flow components have been estimated for the advised intake locations:

107

Table 20: Table of Low (base) flow estimates for Anjouan and Moheli

However given that rainfall is recorded in every month, a more realistic estimation of the minimum flows is considered to be the average driest rainfall month run-off (90%) plus the annual base flow estimate. This is given below along with the equivalent for the wettest month for comparison.

Table 21: Table of the minimum flows during the driest months

When the minimum flow estimates– as derived from 90% of average driest month rainfall plus annual average base flow - are compared with the advised water demand for each zone, then all the intake locations are estimated to be capable of providing the required water demand during periods of dry season estimated low flows.

108

Table 22: Table of minimum stream flow estimates versus water demand for Zones 7-15

The intake locations therefore have been selected to capture water available in chosen watersheds capable of providing year round water supply to the local population.

Surface Water Supply Storage

Water storage tanks should be provided on all the new/upgraded water supply schemes on Anjouan. These should be designed to provide 1 to 2 days of water supply without intake replenishment. They are intended to provide a secure water source during extreme weather events when highly turbid water would otherwise enter the system and damage the filters reducing water quality and potentially blocking the supply network. The ability to shut down the surface water supplies before intense rainfall events is a critical climate change adaptation solution.

The tanks also enable peak daily demands to be met from the tanks therefore allowing low flow periods to sustain daily water supply, even if they cannot meet instantaneous peak demands.

The water supply schemes in Moheli already have adequately sized storage tanks.

Surface Water Supply Treatment

All project water supply schemes should have new or improved water clarification treatment works installed. These should be gravity filters with chlorine dosing.

The primary contamination risk for drinking water supplies is microbiological. Microbiological activity is directly proportional to turbidity in streams as the sediment acts as a growth agent for the microbs. Turbidity also reduces the effectiveness of chlorine dosing, as microbs can impregnate the clay particulates, which results in ineffective treatment and poorer quality treated water.

Climate change is expected to increase rainfall intensity (up to +45%) and therefore increase erosion (by up to two orders of magnitude) in the watersheds, thereby increasing turbidity and reducing raw water quality. Increased storms and run-off will also result in greater mobilization of surficial pollution including oils, metals

109

and wastewater. This will require increased levels of treatment to ensure supplied water quality is fit for the local populace.

It is recognized the local populace may have an indigenous resistance to current or previous water quality turbidity, however this resistance will not provide protection to higher levels of turbidity and associated microbial activity.

Climate change will also increase dry periods and reduce flow velocity, increasing water temperatures and supporting increased microbial activity during the dry periods – thereby necessitating the requirement for higher levels of water treatment.

The current schemes either do not have treatment facilities at all or they are not operational. The project should therefore finance water treatment facilities to increase resilience to climate change impacts on water quality.

Watershed management – to reduce water treatment requirements –is recommnded as part of the national actions.

Surface Water Irrigation Supply and Storage

The project should also finance 109 livestock troughs and 144 micro-basins on Anjouan and Moheli. These would be both rain fed and connected to the intakes where practicable, but irrigation supply will be stopped during the dry season if required for potable water uses.

Using direct rainfall alone, each micro-basin should be able to irrigate an area of 0.5 hectares in average years, and 500m2 in the driest of years.

With excess stream water – i.e. tank overflows supplying the micro-basins when stream flows are sufficient, the cropping area will be considerably higher.

Efficient irrigation systems will be implemented in six zones on Anjouan and in the two targeted zones on Moheli to demonstrate benefits of preventing wasting water.

110

PROPOSED PROJECT INTERVENTIONS GIVEN CURRENT GAPS AND NEEDS

According to the Accelerated Growth and Sustainable Development Strategy, SCA2D, (2015-2019) , the GoC’s vision is to establish a drinking water system, especially for the most vulnerable in line with the principles of sustainable development. The GCF project has been designed to support Comoros in providing access to climate-proof drinking water services. It will furthermore contribute to the vision of the National Water Strategy to increase water supply for 100% of the population by 2030 90 and to a goal of Comoros’ INDC (2015) by contributing irrigation water supply so that country farmers can have a water management system adapted to the evolution of climate change.91

The key outcome of the proposed GCF project is to strengthen the water security for the Union of Comoros to extreme climate change impacts. The project will contribute to achieving three Fund Level Impacts, namely: i) increased resilience of health and wellbeing, and food and water security; ii) improved resilience of ecosystems and ecosystem services and iii) increased resilience and enhanced livelihoods of the most vulnerable people, communities and regions.

To address this goal and to achieve the aforementioned impacts, the Project will set the foundation by increasing the capacities of state, non-state, urban and rural institutions to manage water resources, watersheds and water supply infrastructure in an evidence-based climate risk reduction manner.

The project design process uses the UNICEF promoted Drinking Water Safety and Security Planning (DWSSP) methodology, to identify both climate risks to water quantity and water quality to each potable water supply scheme (be it rainwater harvesting, stream capture or groundwater wells or springs), qualitatively ranks these risks in terms of frequency and intensity and identifies risk mitigation including climate change adaptation solutions to avoid, reduce or minimize these risks to potable water quality and as a secondary objective to irrigation water quantity.

Three inter-connected project components have been developed and validated via extensive stakeholder consultations, including with women, between January 2016 and August 2017. The components provide the foundation to resolve the climate related water scarcity issues affecting water abstraction, storage and source protection issues during periods of future extreme climate variability.

The components include a set of measures that will i) provide the backbone and capacities for water management planning and preparedness nationally and regionally that will account for climate change, ii) provide greater water security at times of climatic stress to all three islands and iii) will support more resilient subsistence farming systems due to improved dry season irrigation water provision.

To increase the quantity and quality of surface and groundwater sources for these populations (peri-urban and rural) with increasingly dry conditions, a mix of water capture, infiltration and storage mechanisms will be used. Designs and management protocols will be aligned with IPCC climate change predictions and country specific water seasonal forecasts in order to sustainably manage increasingly variable water resources by focusing both design and operation & maintenance on risk reduction priorities.

90 The Comoros’ Institute of Statistics has projected the population to be 1.16 million by 2030.

91 Comoros Intended Nationally Determined Contribution (INDC) to the UNFCCC Sep 2015111

In early 2016, national water experts prepared an in-depth pre-feasibility study (PFS) between January and April 2016 that included significant field and stakeholder analyses in addition to technical analysis of more than 40 previous water studies. The PFS provided technical water infrastructure requirements and costs to improve the water supply system for the proposed sites to make them more resilient to climate change. A subsequent socio-economic study annexed to the FP also provided an analysis on the existing sources, quantities and quality of water supply in the targeted zones.92 The socio-economic analysis highlighted the current burdens of water supply such as the average time per day women have to search for water (2.5 hours per day) and the non-standardized rates that rural and peri-urban populations have to pay for water of questionable quality and unreliable quantity. Existing and projected water demands were also verified in each of the 15 target zones in the socio-economic analysis.

In 2017, a climate vulnerability assessment was undertaken on the nation’s water resources and this used to further validate the project strategy and confirm the infrastructure investments to be appropriate.

The 15 target zones on the three islands, comprising 103 villages, have been chosen due to their vulnerability to climate change, their good hydrogeological and hydraulic potential for water storage and capture, limited donor support for water supply in the localities to date and a potential collaboration planned with complimentary donor support (e.g., disaster risk management). The target zones include (see Appendix 11 – Selected Photographs of Sites Infrastructure and Watersheds):

Grande Comore Zones: 1) Bambao et Itsandra et peri-urban Moroni, 2) Ngongwe, 3) Hambou Djoumoipanga, 4) Mboikou, 5) Oichili, 6) Hamanvou;

Anjouan Zones: 7) Hassimpao, 8) Vouani, 9) Vassi, 10) Ankibani, 11) Chitrouni – Saadani, 12) Mjamaoué, 13) Nioumakélé-Bas;

Moheli Zones: 14) Fomboni-Djoiezi, 15) Hoani-Mbatsé.

5.1 Output 1: Water supply sectoral climate risk reduction planning and management

The national long term commitment to and sustainability of climate resilient water supplies is driven by a national enabling environment that places climate change adaptation as an essential, integral and prioritized part of the national water management approach.

The inter-sectoral and multi-agency nature of water management requires coordination of various players to decide upon the measures and actions to address water security. The challenges of climate change must be integrated into any water policy and decision-making mechanism.

This is particularly true in Comoros where national and island (federal state) agencies need to coordinate planning, programming and budget allocation, and overcome fragmented existing institutional coordination.

Output 1 enables better integration of the scientific and technical aspects of climate change into the management of water by guiding the reforms on the decentralization and professionalization of water management that are currently taking place under the revised Water Code (2015). These agencies will assure

92 PFS – Pre-feasibility study : Diagnostic Approfondi de la ressource en eau pour approvisionnement des iles Comores, Avril 2016116

a decentralized relay of information from both bottom-up and top-down and will ensure coherency of water management resilience to climatic impacts.

Storage planning must account for climate impacts such as droughts and floods, while treatment costs must account for climate change repercussions such as increased BOD and turbidity. Abstraction planning requires the knowledge of predicted water capacities. This needs to be undertaken in both an holistic but also systematic framework (i.e. Water Security Planning), therefore requiring climate specific risks to be fully recognised and integrated into national, state and community water resources and water supply polices, strategies, planning and programming.

A Water Security Master Plan will also be developed that will detail guidance and Standard Operating Procedures required during climate extremes to ensure year-round, sufficient and good quality water supply.

A group of trainers (targeting women trainers) will be technically reinforced to ensure the dissemination of climate-informed best practices for all levels of water management. The goal will be to educate water managers and users on the need to assign a fair price on water resources in order to ensure its sustainable and equitable supply in the event of climate extremes.

Strengthening of institutions in charge of managing the water provision infrastructure will be undertaken with training on climate change hazard assessment, use of climate forecasts and early warning systems, water security (risk reduction planning & mitigation measures implementation), national tariff strategies and budgeting for the long-term (extreme climate Operation and Maintenance over the infrastructure’s lifetime) will be provided.

5.1.1 Activity 1.1: Integrating Climate Risks into the national water sector legislation, financing and planning processes

Reinforce existing national efforts in improving the coordination among water sector actors by strengthening Water Code reforms to integrate climate change adaptation, by including climate change risk assessment, risk reduction, planning, budgeting, investment, capacity building, and tariff recovery across the institutional reform tools – including policies, strategies, legislation, regulation, planning and programming, as well as institutional coordination remits, mandates and terms of reference.

Support the adoption and implementation of the Water Code as well as the integration of climate informed best practices within the Code, using a combination of climate risk specific water security and resilience advocacy, awareness raising and guidance to national, island and provincial water sector actors in their planning, budgeting, programming and implementation of their mandated work programmes.

Links to increasing the resilience to climate change

● Avoids redundancies for initiatives responding to water security and streamline the integration and

consideration of climate change impacts.

● Improves uptake and scaling-up of practical and technical aspects pertaining to climate change

adaptation in the implementation of strategies and planning.

117

● Ensures long-term continuity of the water distribution and treatment infrastructure by adopting

sustainable and socially sensitive pricing mechanisms that account for existing and predicted climate change impacts.

● Implements climate smart water production and distribution systems.

● Links future infrastructure support to evidence base of existing risk reduction through improved

management – incentivisation to improve existing infrastructure to gain access to climate resilient upgrades.

Alternatives considered, best practices and most cost-effective solutions

● Actions build on the guiding principles of the on-going reform of the institutional framework

established in the Water Code, exploiting its timeliness to integrate climate change considerations.

● Actions are inspired by experiences in other small island developing states challenged by similar

climate risks (Cape Verde, Sao Tome et Principe, Seychelles and the Pacific SIDS) as well as socio-economically similar countries (Mali, Burkina Faso, Mauritania, Chad, Niger and Cameroon).

● The current non-standardized tariffs, established in 1978, do not meet the costs of climate resilient

infrastructure maintenance.

● Standardization of tariffs would provide means to cover extra costs of climate risks and ensure access

to water for vulnerable socio-economic groups.

5.1.2 Activity 1.2: Strengthening water providers on climate risk reduction water climate risk reduction design, operation & maintenance

Enforce decentralized water resources management capacities with the goal of building climate resilience in rural and peri-urban areas by building capacity in Water Safety and Security Planning (DWSSP) and implementation.

Provide awareness and improve technical capacity of water supply institutions (ANACM, MAMWE, EDA, UCEDA, ACIM) and rural Water Management Committees on understanding climate change risks and impacts on water resources, adopting Drinking Water Safety and Security Planning (DWSSP) approaches for the protection and conservation of water resources and recognising the costs necessary for the efficient production, treatment and distribution of water during periods of extreme weather.

Raise awareness and train associations and community management committees in climate-smart water management – i.e. risk reduction approaches and monitoring and evaluation of risk reduction benefits.


● Reinforces technical capacities of water management committees with climate-resilient rural water

management and the establishment of local preparedness and risk reduction action plans to respond to climate-related risks.

118

● Establish national, island and community Water Security Plans and warning systems against climate

risks and identify, implement and monitor performance of resilience measures & actions to avoid, reduce, and overcome calamities.

● Link future government assistance and infrastructure investment with an evidence base of reduction

of existing water supply climate risks.

● Trains instructors to be able to relay best practices on climate change adaptation to management

associations and committees including water supply hazard identification, risk assessment, risk reduction

● Supports decision-makers in accounting for climate change related issues.

● Increases water service provider management capacity to systematically identify climate risks, reduce

risks through careful design & construction, and operation & maintenance procedures, including raw and treated water quality monitoring to inform adequacy of risk reduction approaches.


● Existing community-based management schemes have largely failed, in terms of transparency,

collecting tariffs, initiative, leaving many water distribution networks in a highly vulnerable state.

● Climatic hazards and their risk reduction will be addressed by regional commissions made up of

representatives of public entities such as the DGEME and linked to water supply scheme operation, maintenance and capital investment.

● Currently, the Water Committee Union (UCE) provides assistance to Water Management Committees

(WMCs). Because end-consumers do not pay the true cost of their water consumption, the UCE is perceived as a burden and is typically only active in investor-funded infrastructure projects.

● Under the current water reform program, UCEs will be professionalized and their role in providing

climate risk reduction technical support to local councils, including the transfer of knowledge, will be recognized.

● The delegate management approach stipulated in the Law of April 7, 2011, on decentralization is

deemed feasible in Comoros if it is accompanied by a transfer of competencies to the villages, including bolstering human and material climate resilience capacities in the villages and reinforcing the competencies of all involved. By linking this to system upgrades only once DWSSP is proved to be operational – this mainstreams CCA into O&M practices and re-investment incentives.

5.2 Output 2: Climate Informed Water Resources and Watershed Monitoring and Risk Forecasting

Output 2 will support an integrated approach to climate change resilient water management by creating Integrated Water Resources Management committees that will guide water abstraction, land use and related

119

protection activities at the watershed scale to maximise natural resilience to climatic extremes (droughts, floods and water turbidity).

The revised Water Code has mandated the establishment of the IWRM committees to focus on ensuring groundwater and surface water recharge and watershed protection. By officializing the IWRM committees and building their capacities to plan and budget, they will serve to coordinate with the DGEME (role of water supply) and the DGEF (role of water quality) at the national level, the DREA at the regional level and will work with the communes at the local level.

The IWRM committees will be responsible for generating watershed specific Plans of Action based on initial Climate Risk Vulnerability Assessments (CRVAs) to be conducted. The CRVAs will provide a cartographic inventory of areas exposed to climate risks.

The IWRM Plans of Action will detail the most appropriate climate change eco-system-based adaptation measures to ensure the conservation, protection and sustainability of water resources and watersheds. The development of these plans will be community-focused, gender-sensitive and elaborated in a participatory manner.

These plans will detail feasible watershed management and restoration activities including zoning of source water areas, re-vegetation in riparian zones and reforestation of river basins so that water resources become more resilient to hydrological extremes. The zoning areas will be established by decree under the Water Code.

The collection, analysis, interpretation and dissemination of water resources data for all aspects of the water cycle (rainwater, surface water, groundwater, evapo-transpiration) allows identification of vulnerability of water resources to short term and long term impacts due to climate change. Effective water resource monitoring enables agencies/ organizations will develop adaptation strategies including optimizing water resources exploitation but also early warning systems.

Output 2 will contribute to improving water resource data management through the procurement and installation of 10 hydrological gauging stations in Anjouan and Moheli and the procurement and installation of 43 piezometers across Grande Comore (30), Anjouan (8) and Moheli (5). All water related monitoring stations will be coupled with the existing synoptic stations, automatic weather stations or with the rain gauges already installed. Such water-related climate information will be collected by technical servicemen to be trained under climate-informed training programs. Data will be treated, archived and shared by the Directorate of Meteorology.

The technical capacities of staff in the Directorate of Meteorology will also be reinforced in collaboration with the GEF DRR project. Capacities will be improved in-house using near-by trainings offered (e.g., WMO, IGAD) and by exploiting existing university knowledge.

The University of Comoros is working with the MAMWÉ to monitor groundwater salinity levels brought about by saltwater intrusion. The University has the only laboratory in the archipelago that can provide reliable information on water quality and in piezometric measurement. As a result, the University will be heavily involved in training on water resources and in updating existing curriculums of graduate level classes and for continuing education in order to integrate climate change. By setting the framework for improved education a future generation of technically-savy, climate change aware recruits can be produced to support water resource data collection, analysis and interpretation. For instance, the University of Comoros’ programmes

120

will establish academic and professional training modules focused on the integration of climate change in existing sustainable water management programmes.

Output 2 will furthermore focus on training for decision-makers and users of tailored hydro-meteorological information and products to improve water management.

Due to enhanced capacities brought about by Output 2, customized water-related forecasts will be developed for targeted user agencies (e.g., Farmer associations) and local community end-users to assist with water conservation, water demand suppression and water quality protection during drought and flood periods. Staff in key departments and local authorities will be trained in interpreting water-related climate and weather forecasts to support their decision-making processes.

5.2.1 Output 2.1: Strengthening Watershed Management and Eco-system Based Adaptation Planning and Implementation

Establishes and formalizes IWRM Management Committees in each target watershed to have clear mandates for coordination, knowledge transfer of field practices and to have the role of surveillance of protected areas and to promote watershed recharge, in accordance with Section 2, Article 28 of the revised Water Code, to reduce vulnerability of watershed to climatic extremes and ensuring a gender inclusive approach, using catchment hazard characterisation to develop prioritized watershed management action plans to reduce climatic impacts.

Establish and implement specific tangible activities to promote watershed management in order to increase resilience to droughts and floods using sustainable land, waste and wastewater management – prioritized through watershed characterisation climate risk assessments and implemented through watershed climate resilience plans, including soil conservation, water conservation, pollution reduction, water retention and recharge augmentation approaches.


● Promotes IWRM as an essential tool in addressing the impact of climate change on water resources –

dry season water resource retention, flood flow attenuation, soil stabilization and erosion reduction, water quality oxidation.

● Improves the climate resilience of socio-economic activities by working at the watershed scale, which

most accurately reflects the availability of water resources in each individual watershed.

● Promotes the rehabilitation of forest cover upstream of groundwater and river recharge zones,

increasing the resilience of water resources in the context of climate change through flow attenuation and release, and erosion prevention.


● IWRM was recognized as a key element to meeting the Sustainable Development Goals (SDG Target

6.5) for water, by promoting “the coordinated development and management of water, land and related resources in order to maximise economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems.“

121

● Institutional reform to comply with IWRM should be tied to the creation of a National Water Policy

that is consistent with the precepts of IWRM, and the revised Water Code should be rigorously enforced.

● Reforesting with non-native but high market value species to improve livelihoods

5.2.2 Output 2.2: Watershed Adaptation Legislation and Public Awareness Raising

Support IWRM Management Committees to establish and maintain climate risk reduction water source protection zones in accordance with Article 28 of the revised Water Code using both regulatory and non-regulatory approaches.

Increase professional and public capacities for climate-informed IWRM and raise public awareness on the impacts of climate change, water conservation and anti-pollution measures to self-regulate and enforce protection zones.


● Regulates socio-economic activities to protect and preserve existing and future water resources from

climatic extremes.

● Supports national entities in planning and budgeting IWRM, conferring the role of promoting best

practices for climate change adaptation to the Ministries of Health and of the Environment.

● Supports communities to self-regulate watershed adaptation measures and not rely on government

enforcement.


● Law No. 11-005/AU of April 7 on decentralization transferred the responsibility for rural water supply

and sanitation to the villages. This process, which has yet to be carried out, should be accompanied by a transfer of resources and competencies, establishing the villages as responsible for the management of water supply and sanitation infrastructure.

5.2.3 Output 2.3: Water resources management and monitoring, hazard and risk assessment and drought and flood forecasting

Acquire and install ten hydrological gauging stations and 43 piezometers to improve water resources management by reducing vulnerability to flood and droughts.

Strengthen the technical capacity of staff from the Direction of Meteorology to produce drought and flood forecasts for different sectoral targeted users and develop appropriate climate risk products for use by different sectors, including developing and operating early warning systems

122


● Improves monitoring capacity throughout the water cycle to better anticipate and respond to climatic

impacts on water resources and therefore water supply.

● Provides data essential for IWRM, providing a detailed understanding of the recharge and discharge

dynamics of the groundwater reservoirs at the watershed level including critical contribution to sustaining extreme dry period stream low flows

● Trains experts to gather, process, and interpret data informing about the state of the water resources

prior to and during extreme climate events, and to define thresholds for alerts that will have to be adjusted over time to optimally anticipate water stress and trigger climate resilience preparedness and response action plans.


● The existing monitoring network will be upgraded to include additional meteorological, hydrological,

and hydrogeological sensors and gauges.

● New weather stations will refine the mesh of the existing monitoring network, providing a deeper

understanding into the climatic conditions and facilitate predictions of future climate and quantification of groundwater reservoir recharge.

● Hydrological flow monitoring will be carried out where water intakes are to be restored, avoiding the

need for additional facilities.

● Automatic hydrogeological probes will be installed in existing boreholes, providing sufficient territorial

coverage while avoiding the need for additional boreholes.

● Link to Regional Specialised Meteorological Centre (RSMC) in Reunion that has WMO mandate for

cyclone prediction and climate change meteorological monitoring in the Southern Indian Ocean.

5.2.4 Output 2.4: Climate adaptation products generation using hydrological forecasts and sector application

Train Agricultural Associations, Water Management Committees, NGOs/CSOs and water users on the interpretation and use of drought and flood forecast products and water-related newsletters as well as receiving early warnings of flood and drought risks, ensuring a gender-inclusive approach by including women participants and having women trainers.

Train young recruits with the collection, analysis and interpretation of water resources and climate data relevant to water resources management and protection, ensuring a gender-inclusive selection of participants and target 50 per cent women.


● Trains local users to interpret climate forecast products and tools informing about the state of the

water resources, in particular during extreme climate events, and to define thresholds for alerts that 123

will have to be adjusted over time to optimally anticipate water stress.

● The University of Comoros will be charged with ensuring the succession of technical staff through the

establishment of academic and training modules focused on integrating climate change into existing sustainable water management programmes.

● Links to the University of the South Pacific and the University of the West Indies on their climate

resilience education programmes as well as other regional SIDS water security capacity building programmes and those in the University of Mauritius (which runs an MSc in Climate Change Adaptation and Risk Reduction).


In the long run, technical staff will have to be trained locally. The University of Comores will be a key player in this endeavor, as it already monitors the quality of drinking water distributed by MAMWE on Grand Comore. Existing capacities include a water analysis laboratory for the detection of bacterial contaminations and competencies for carrying out piezometric and water quality surveys to detect saltwater intrusion. Furthermore, it is already involved in studying groundwater aquifers. Through its existing academic and training programs, the University of Comoros will be able to contribute in resolving climate change related issues pertaining to the quality of the islands’ water resources.

5.3 Output 3: Climate resilient water supply infrastructure

Output 3 includes infrastructure measures to improve drought water supply security through increases in abstraction, distribution and storage structures, as well as protection and resilience to extreme storm damage and erosion (see Appendix 12 – Detailed Water Supply Infrastructure Types).

The GCF project will focus on 1) expanding water storage mechanisms for dry periods and the increasing demand due to high temperatures, 2) climate-proofing water sources and infrastructure from storms and flood damage (e.g. elevating pump stations, using protective covers for reservoirs, temporary intake closure valves, controlled overtopping of intakes), and 3) filtering and treating water in a cost-effective manner to account for climate change linked water quality deterioration impacts (specifically but not limited to increases in turbidity and microbial activity - BOD).

Depending on the physical characteristics of watersheds and the types of climate related risks they are exposed too, the project includes the upgrade of surface water and groundwater abstraction systems as well as rehabilitation and/or construction of specific rainwater harvesting systems (e.g. impluviums and some ‘eco-tanks’ (stand-alone tanks with roof catchments).

Rather than opt for a single type of solution, which could increase susceptibility to climate change impacts, this output will provide each island with more diversified sources of water supply. Studies have indicated that natural resources are sufficient to ensure a continuous water supply if managed sustainably. Current exploitation of groundwater and of surface water and RWH is 0.5% and 1.9% of the total annual renewable volume.93 Whilst surface water catchments are very flashy and have potential to have very low dry seasons

93 African Development Bank, Strategy and Programme of PEAPA in the Comoros: Hydrologic and water resources balance, Annex 2: Hydrogeologic context, Socio-economic context, Water resources monitoring

124

flows, great amounts of fresh groundwater resources are also thought to exist in Anjouan and Moheli, on perched aquifers for instance. Due to a lack of groundwater studies, this source has never been exploited. 94

Activities include conducting drought period groundwater saline up-coning vulnerability assessments to avoid over-exploitation and to mitigate the risks of saltwater intrusion and evaluating surface water and rainwater harvesting capacities. These studies will provide a better understanding of the dynamics of runoff and recharge in the watersheds.

Due to relatively low Operation and Maintenance requirements, rainwater harvesting would normally be emphasized where practical, but in-country observations and water balance analysis suggests both opportunity for household scale improvements and resulting benefits are severely limited. Rainwater harvesting opportunities do exist however for increasing the resilience of irrigation and improving dry season food security.

In places where roof surface areas are minimal and where boreholes can be constructed in shallower, productive groundwater supply areas, boreholes will be upgraded and constructed. In contrast, on Anjouan and Moheli, climate-proof river intakes will be constructed to ensure they are not damaged by flood events or blocked by sediment.

Similar to Grand Comore, both Anjouan and Moheli will use non-potable rainwater harvesting for increasing rural irrigation water security. In the case of these two smaller islands whose target villages are located and economically dependent on the river basin, the surface water will continue to be abstracted.

All storage tanks attached to source water abstraction and rainwater harvesting tanks will be equipped with the appropriate water disinfection and filtration systems. The tanks will reduce peak demand over-exploitation of groundwater and thereby reduce saline-up-coning risks, whereas the tanks will provide some buffer to surface waters during droughts and provide the flexibility to close stream intakes during temporary storm events when turbidity levels and pollutions risks increase.

Reservoirs, impluviums and water troughs will also be rehabilitated and constructed for non-potable uses including agriculture. Impluviums, or natural craters collecting rainwater, will continue to be used for agriculture due to their tradition in the Comorian culture. The impluviums are located above the villages enabling gravity feed pipelines to be constructed.

Finally, in order to promote better management of water resources during periods of water scarcity, water flow meters will be installed. They will be used to document the consumption of beneficiaries, enable better water conservation planning, provide an evidence base to determine system leakage rates and consequently secure drought operation & maintenance budgets to prevent and reduce water wastage to assist drought resilience. Water supply leakage rates are expected to be >25%.

5.3.1 Activity 3.1: Climate Risk Reduction of Existing Groundwater Boreholes and Expansion of Groundwater Exploitation

Conduct Climate Risk Water Safety and Security Assessments of existing boreholes including hydrogeological testing campaigns in order to quantify the potential existing supply yield of groundwater sources, determine

94 DGEF, UNDP, GEF April 2012. Report on the Vulnerability and the Adaptation of Water Resources at Risk to Climate Change Impacts on Anjouan.

125

vulnerability to saline up-coning, determine optimum pumping regimes during extended dry periods and undertake storm water inundation pollution risk assessments and implement mitigation measures. Drill, test and protect new groundwater abstraction wells/boreholes.


● Ensures optimal use of existing boreholes in Zones 1, 2, 4 and 5, by establishing maximum drought

period withdrawal rates to minimize the incidence of saltwater intrusion into underground aquifers.

● Protects source water abstraction points to guarantee water quality and the continuity of the

infrastructure from storm run-off flood inundation.

● Expand drought period drinking water capacity by adding an additional borehole in each of Zones 1, 3,

4 and 5 to complement rainwater harvesting and restricted borehole supply systems already in place in these regions.


● Groundwater reserves on Grand Comore, totaling 1.25 billion m^3 / year are sufficient to supply the

island with water.

● Exploiting groundwater should be given preference whenever possible for several reasons: (i) it does

not require the construction of large-scale and costly storage basins; (ii) it requires less treatment, as groundwater is partially filtered as in infiltrates into the reservoir, (iii) in regions with insufficient rainfall, groundwater reservoirs can cover water needs over prolonged durations.

5.3.2 Activity 3.2: Climate Risk Reduction Upgrades and Extensions to Water Supply Networks

Upgrade / construct new water supply facilities to ensure water security based on water demands projected during dry periods and increase resilience to flood and high flow physical damage, sediment ingress and water quality derogation.


● Increases water supply and storage facilities to ensure water security in climate change extended dry

periods.

● Increases resilience to climate change by reducing dependence on a single water source by

diversifying water supply types and sources contributing to distribution systems.

● Increases resilience to climate change by reducing flood damage to water supply systems.

● Diversifies abstraction points for agricultural and domestic uses (impluviums, micro-basins and

livestock troughs) without depriving the population of potable water, thereby reducing their vulnerability to climate fluctuations.

126


● Villages lacking access to dry season and flood period potable water and those most vulnerable to

climate change will be given priority.

● Household rainwater harvesting systems are failing due to inadequate roof size not lack of storage.

Increasing household rainwater harvesting is therefore not an option. .

● Impluviums exploit natural craters to collect non-potable rainwater for agricultural use, contributing

to the diversification of water sources according to their use and quality. Adopting water efficient irrigation techniques would further reduce water demand during dry periods.

● On the Islands of Anjouan et Mohéli, surface waters are only marginally sufficient to cover water

needs in dry seasons – additional intakes will increase the low flows that are exploitable.

● Climate-proofing stream water intakes would contribute to increasing the resilience of the water

supply. This would involve reinforcing the infrastructure to withstand extreme flooding events, preventing extreme turbidity and debris ingress, increasing filtration capacity to treat turbidity.

● Expansion of existing water distribution networks will increase water security to those communities

currently reliant on only household rainwater harvesting and manhandled container access to streams.

● Upgrading leaking water distribution networks will reduce unaccounted for water (UFW), reduce

exploitation of water resources and increase dry season water availability

5.3.3 Output 3.3: Installation of Flow Meters to inform Climate Risk Reinvestment Tariff Setting and Leakage reduction

Installation and monitoring of water production, consumption, delivery performance during climatic extremes, and identification and leakage repair effectiveness to reduce non-revenue water.


● Promotes the installation of water meters at the Water Management Committees to quantify water

consumption, establish a sustainable pricing scheme to support climate resilience investment and operation & maintenance, and improve planning in the context of climate change.

● Reduction of unaccounted for water during drought periods, minimizing demand on vulnerable water

resources.


● Tariffs not supported by actual meeting and risk of not achieving adequate cost recovery.

● Repairing of only visual leaks and failing to adequately reduce lost water demand.

● Repairing minor leaks and not targeting main losses from system.

127

5.4 Assumptions and risks grounding the design of the project strategy

The project strategy has been designed assuming the following elements:

● Water Code reform and the importance it highlights for IWRM will be supported by the GoC.

● Institutions and organisations will commit to revised national legislative drivers

● Institutions and organisations have technical capacity to understand and use the information products/services in a timely manner

● Institutions and communities have adequate technical capacity to receive upskilling and use adaptive management approaches to reduce risk

● Watershed communities engage in project and have capacity to deliver and sustain IWRM watershed improvements

● Households have capacity to receive and use information in awareness campaigns

● Utilities fully adopt new management systems to improve service delivery, including O&M planning.

● Sufficient rainfall, groundwater and surface water can be collected / mobilized to help achieve water security.

● Women will be attracted to working on WMCs and allowed to sit on those committees.

● WMCs have capacity to understand and use the DWSSP approach.

● Staff of the relevant institutions and communities members uptake of training and capacity building on water resources management

The risks factors threatening the successful implementation of the project strategy are presented in the table below.

Risk Factors and Mitigation Measures

Selected Risk Factor 1: Remoteness of Beneficiary Country

Description Risk category Level of impactProbability of risk

occurringInternational supply chains are long, expensive and prone to shipping delays.

Country staff have little/negligible experience of international procurement procedures (ICB)

Technical and operational

High (>20% of project value)

Medium

Mitigation Measure(s)

128

The international logistical and procurement issues will be mitigated through a combination of the provision of appropriate logistics and procurement technical assistance to the PMU/PCU to ensure supply chains and times are well understood, delivery contingency plans are prepared, and detailed procurement tasks and timeframes are incorporated and integrated into the project work plans.

Risks can be further mitigated through use of carefully prepared pre-qualification criteria for suppliers, requiring demonstrable international experience of trans-Indian Ocean product & material delivery and incentivizing suppliers to use reputable shipping agents, as well as scheduling deliveries to coincide with more convenient times of year (away from holiday periods and monsoon seasons).

Selected Risk Factor 2: Remoteness of Project Sites


occurring

The project sites are located across three separate islands as well as some at remote upland locations within these islands, dependent on inter-island transport as well as off-road vehicles and well maintained access tracks.



Medium


The national logistical and access issues will be mitigated through a combination of ensuring the PMU/PCU has adequate access to national logistics expertise, the use of contingency planning, integration of logistical tasks and timeframes into the work plan and sympathetic scheduling of shipment arrivals (i.e. during the dry season).

In addition, the project resources will ensure adequate dedicated off-road vehicles are available to project staff, and where local construction contractors are used they will be required to demonstrate experience and resources to cope with difficult terrains as part of the tendering process. If government departments are used evidence of similar experience will be required

Where ground conditions are difficult, the project will allow for phasing of construction of access roads and construction platforms in advance of actual infrastructure activities. If necessary, these will be completed the dry season before infrastructure installation.

Selected Risk Factor 3: Limited Qualified Staff


occurringLimited in-country technical, managerial and procurement expertise in critical project areas

Inappropriate or inadequate delegates at training workshops

Conflicting demands on key governmental and non-governmental staff


Medium (5.1-20% of project

value)

Medium

129

Mitigation Measure(s)The risk relates across the project stakeholder groups including governmental departments, non-governmental organisations and even the UNDP office – and reflects the limited on-island population size and exposure to alternative approaches other than business-as-usual.

The risks will be mitigated through the following actions:

● Careful selection and deployment of appropriately experienced international technical advisors to support

knowledge transfer

● Early political advocacy and public awareness raising to ensure ministerial, institutional and community

support to project objectives

● Careful pre-selection and vetting of training opportunities nominees

● Use of Training-the- Trainer approaches to increase capacity outreach

● Backstopping and buddying of local staff with national and international experts

● Careful monitoring and assessment of project delivery

● Development of locally delivered and institutionalised training programmes

Adopting and monitoring the success of these approaches is expected to reduce the residual risk to low.

Selected Risk Factor 4: Extreme Weather & Seismic Events


occurringExtreme weather events restrict monitoring deployment, infrastructure construction and watershed land use activity periods and delay/limit inter-island access.

Natural hazards damage and/or destroy pre-existing and or project activities, and create short-term response & recovery priorities for government and communities.

Social and environmental


Low


The scheduling of field and construction activities has allowed for concentrating activities outside of the wet season and into the dry season – including where necessary pre-construction dry season preparatory works e.g. access road building and material shipping to minimize later impacts on construction during wet periods, with non-field based activities during the wet seasons e.g. training.

Early deployment of hydrological monitoring equipment will allow value of hazard and risk mapping & monitoring to be observed during the hazard events – with the project demonstrating the role of adaptation and resilience

130

during extreme events – e.g. use of early warning systems.Contingency planning will ensure option exists for project to focus on Grand Comore alone during periods of rough seas, whilst can focus on Anjouan and Moheli should volcanic activity on Grand Comore become problematic e.g. ash falls.

Selected Risk Factor 5: Community Ownership


occurringCommunities not committed to effort required to strengthen capacity in adaptive management, preferring government hand-outs and infrastructure gifts

Social and environmental

Medium (5.1-20% of project

value)Medium


Targeted community involvement already within the project design phase, including signing of agreements to support project.

Early scheduling of public awareness campaigns to reach urban and rural population.Deliberate engagement and involvement in IWRM committees and Water User Associations

Intentional targeting and involvement of communities in resilience planning, participatory hydrological monitoring, climate adaptation product/tool development.

Community involvement in simple construction tasks and training/upskilling on more complex tasks.

The residual risk can be reduced to low with careful and sustained engagement and communication with direct and indirect beneficiary communities.Selected Risk Factor 6: Political Commitment


occurringSenior national, island and community political key stakeholders distracted by other priorities, projects and parliamentary cycles as well as shock events.

Disengagement or hostility to project.

OtherHigh (>20% of project value)

Low

Mitigation Measure(s)Careful engagement with senior government representatives during the project design process.Promotion of project as an inter-sectoral multi-stakeholder approach with equity and equality in its objectives.Transparent and accountable target community selection not influenced by local political preferences.Transparent and accountable project delivery decisions.Strong communication with government through well established and respected UNDP CO staff.Recognition of parliament annual cycle and necessity of timely inputs to governmental decision making bodies.

Other Potential Risks in the Horizon: Land Disputes

131

Community and individual ownership of land has potential to delay and impact on project, especially as ransom strips.

This issue has been largely mitigated through identification of land ownership, concept design of interventions to maximize use of government land, and signing of Memorandum of Understanding with communities to secure project intervention in their areas.

5.5 Consideration of gender

The project will lay focus on gender sensitive planning and implementation to ensure the highest gains in the fight for gender equity. Since women are responsible for fetching water and subsistence farming tasks such as collection of firewood, women and female children are more exposed to climate risks such as water insecurity and drought. The project will use a gender-differentiated outreach and engagement. Many of the community beneficiaries will be women, especially in the rural areas where they are often active members of Water User Associations. Initially, a gender-sensitive survey will evaluate the best communication channels to get easily understandable water-related planning information to women. Please see the Gender Assessment and Action Plan in Appendix 13 – Gender assessment and action plan.

5.6 Targets and indicators

The expected key Fund Level impact is increased resilience of health and well-being, and food and water security for the most vulnerable people and communities in the Comoros.

A summary of the impact potential is summarized below:

Fund-Level Impact 1.0: Increased resilience and enhanced livelihoods of the most vulnerable people, communities and regions

Target: 100% of target households adopting wider variety of climate change coping strategies

Fund-Level Impact 2.0: Increased resilience of health and well-being, and food and water security

Target: 100% of target HHs have 24 hour access to good quality, sufficient water supply in climatic extremes (35 l/d) (225,000 female and 225,000 male residents)

Fund-Level Impact 4.0: Improved resilience of ecosystems and ecosystem services

Target: 32 target area watershed eco-system based adaptation established or enhanced

Other related targets include:

Output 1

● Integration of climate change resilience into water supply infrastructure designs and water quality

standards in an Order in Council under the Water Code

132

● Development of a water security plan for each of the three islands

● Tariff structure introduced in the 103 villages capable of sustaining climate resilient infrastructure and

climate resilient O&M

● 11 Comorian institutions (DGEF / 3DREF, DGEME / 3DREME, UCEA / UCEM, MAMWE) including

climate change risk reduction in responsibilities, work programmes and budgets

● 100% of engaged water sector organisations mainstreaming Drinking Water Safety and Security

Planning

● 100% of engaged Water User Associations trained in scheme scale Drinking Water Safety and Security

PlanningOutput 2

● Creation of 26 IWRM committees (6 Grand Comore / 15 Anjouan / 5 Mohéli) with representation of

the minimum 30% of women

● 26 IWRM Action Plans developed for targeted watersheds

● 32 (6 Grand Comore / 19 Anjouan / 7 Moheli) zones of protection created in the watersheds (because

villages cross borders)

● 32 (6 Grand Comore / 19 Anjouan / 7 Mohéli) climate risk vulnerability assessment s carried out for

each catchment area

● 100% of catchments reduced climatic risks to water resources

● Approximately 103 rural and peri-urban communities sensitized to flood and drought adaptation

strategies to address climate change

● 60% coverage of water resources monitoring network

● 32 dry season catchment water balances estimated

● Drought forecasting products received by 60% of target populace

● Water advisories used by 100% of target farmers

Output 3

● Drought resilient water supply infrastructure for 450,000 people

● Flood resilient water supply infrastructure for 450,000 people

● Increased irrigated area of about 150 hectares for dry season agricultural production

● Leakage rate reduced by 30%

133

5.7 Expected environmental and social benefits and co-benefits

For Small Island Developing States (SIDS), addressing climate change as well as reducing exposure to other climate specific natural disasters are actually integral components to achieving sustainable development, and indeed failure to recognize and address this objectives will result in failures to achieve sustainable development. This is well articulated in the global SIDS position statement on sustainable development – the S.A.M.O.A. Pathway – and has been highlighted earlier in this document.

Notwithstanding this need for a closer recognition of this inter-connection for SIDS to reduce their vulnerability to natural disaster risks and other development challenges, the following co-benefits are recognized as being realized by the project.

Environmental Co-Benefits

Improved and enhanced water resources in terms of quality and quantity

The project will reduce groundwater salinity through improved understanding of the available groundwater resources (sustainable yields), their vulnerability to drought (drought yields) and optimizing how best to exploit the groundwater without resulting in saline up-coning.

The watershed rehabilitation activities in 32 catchments will contribute to groundwater (and surface water) quality and quantity improvements by slowing runoff and increasing groundwater recharge. They will also reduce pollution risks to both water resource types.

Water conservation measures – supply system leakage reduction, user conservation, and more efficient irrigation will reduce water abstraction contributing to fresher groundwaters and greater stream baseflows.

Improved soil quality and reduced erosion

The watershed improvement component includes soil erosion reduction measures, through both improved farming practices and reforestation and revegetation efforts with native, drought-tolerant species.

The reduction in stream peak flood flows and storm run-off will also reduce direct erosion of soils and land.

Improved biodiversity The watershed improvement component directly supports watershed reforestation and re-vegetation of habitats.The improved water quantities (greater baseflows, reduced flood flows) as well as reduced stream turbidity will all contribute to healthier aquatic eco-systems and those wider eco-systems that in turn are dependent upon the riverine eco-system corridor health e.g. the nearshore marine environment and wider watersheds.

Increased carbon sequestrationAlthough not an explicit objective of the project, the increased re-forestation and re-vegetation of the watersheds will increase carbon sequestration in the country.

Social Co-Benefits

Improved Health

134

The project will improve drinking water quantity and quality to 450,000 people throughout the year, including in periods of droughts and during and after cyclones and associated flooding events.

Reduced Lost Time – Access to Education and Work

Currently rural communities (especially women) spend considerable periods of time fetching and carrying water, especially in the dry season, but for some communities this is year round. This saving in lost time provides an opportunity to increase school attendance and/or work on household income activities.

Improved Safety in Climatic and non-Climatic Disasters

The climate forecasting linked to storm event flash flood forecasting will provide an early warning system for extreme flooding events. This will enable vulnerable communities and those working in or near streams to safely evacuate to higher ground.

Community Empowerment

The project focuses on increasing the capacity of rural communities to manage and protect their water supply schemes. This development of adaptation management capacity will strengthen the accountability of wider community governance generally and can be applied to other sector/issue resilience more specifically e.g. food security.

Economic Co-Benefits

Reduced Costs of Climatic Damage

The timely forecasting and prediction of flood events will reduce the economic damage to all sectors from flood water inundation, as well as improve event response and recovery performance. The April 2012 floods were estimated (by COSEP) to cost US20 Million, 5% of Comoros GDP.

Water supply utilities will design, locate, construct and operate and maintain water supply schemes which will be less exposed to drought and flood risks and therefore will have reduced event associated damage and repair costs.

The provision of a more regular water supply during droughts and floods will reduce losses associated with business/trade/manufacturing operation disruption.

Increased Employment Opportunities due to Improved Health

The 450,000 people receiving improved water supplies will have better health and therefore can be more productive in their household incoming earning activities – either informal or formal in nature.

More Productive Agricultural Sector

The agricultural sector has very little irrigation infrastructure with which to reduce exposure to the dry seasons. The project will increase irrigation water storage using impluvium and stream water intakes to increase dry season cash crop productivity.

Direct Employment opportunities135

Adaptation interventions such as impluvium rehabilitation, water supply construction upgrades and even watershed improvements will all require construction workers, field workers, material suppliers and importers, which will create employment opportunities in the country.The wider project enabling environment will require a permanent increase in technical, management and financial capacity across a wide breadth of different ministries, agencies and organisations, including meteorologists, hydrologists, hydrogeologists, water risk reduction engineers and so on.

Gender-Sensitive Development Impacts

Women and girls are disproportionately affected by inadequate water quantity and quality in the following ways:

• Food insecurity – women are responsible for food collection and preparation;• Household health problems – women take the primary lead on household health and care;• Loss of household income – disproportionately affects women and the finances available for their

primary activities in the household;• Disruption to education – women are the primary collectors of manual water capture and lose hours,

days and weeks to girls education;• Poor hygiene and sanitation – women disproportionately suffer from non-segregated sanitation and

have specific menstruation hygiene requirements that require attention;• Reduced social cohesion due to community disputes over available water during shortages –

impacting on domestic violence and on womens more prominent role on household health, hygiene and food security

• Exclusion from community decision making – women are not always permitted to engage in or vote on community management issues.

By providing better quality and quantities or water to communities, especially during droughts and after cyclonic flooding events, women receive a greater benefit in addressing their daily challenges worsened by inadequate water supplies – as articulated above.

In addition the project specifically advocates the increased role of women in community decision making as well as gender equity in governmental organisations and employment opportunities.

5.8 Knowledge management and learning

Knowledge and learning are critical to building adaptation capacity, both within government and in the wider general public.

Knowledge and learning are therefore embedded across all four components of the project design as approaches to increase resource and infrastructure sustainability, build capacity, promote partnership, ensure ownership, secure political support, raise awareness and deliver evidence based risk reduction planning and management of the nation’s water resources and water supply schemes.

These include both formal and informal knowledge strengthening and learning activities, including:

● Climate change risk knowledge and information sharing integrated into the Water Code;

136

● Assessment, guidance and standards for tariffs required to fund climate adaptation design, operation

& maintenance of water supply infrastructure;

● Inclusion of risk mapping, risk reduction actions, source protection, climatic extreme operation &

maintenance best practise and water quality standards in the Water Code;

● Training of national and island government agencies in implementation of the revised climate risk

reduction Water Code;

● Promotion, development, training and use of Water Safety and Security Planning during climatic

extremes for government and water management committee stakeholders;

● Water committee and community training on water conservation and efficient production of potable

water;

● Training in IWRM governance to IWRM committees;

● Knowledge generation from watershed characterisation including climate hazard and risk mapping;

● Training of IWRM committees and watershed communities in climate risk adaptation strategy options

planning and budgeting, management and required monitoring;

● Development of evidence-based watershed adaptation action plans and knowledge exchange with

island and national agencies;

● Implementing watershed adaptation plans involving community and other stakeholder awareness

raising – including soil and water conservation, source protection and pollution prevention and groundwater recharge techniques;

● Investigation, assessment and guideline development on optimum well pumping techniques to

minimise saline up-coning, and training of water supply service providers;

● Knowledge transfer of UNICEF Pacific Drinking Water Safety and Security Planning (DWSSP)

approaches, guidance and materials

● Development of Comoros best practise DWSSP documents for water supply service providers and

communities – including location selection, design, construction, operation & maintenance, emergency procedures and drought preparedness responses;

● Training in water supply system performance monitoring during climatic extremes;

● Investigation, assessment and characterisation and monitoring of groundwater, stream and rain water

resources, reliable yields and vulnerabilities to climate risks;

● Training of Meteorological service in climate forecasting, drought forecasting and floods forecasting;

● Development of standard procedures for data collection, processing and analysis and training in water

resource monitoring network maintenance

● Training on application of rainfall predictions to water resources balances and risks of water supply

failures;

● Training of different sector water users on water resources forecasts and information advisories;

137

● Training on forecast dissemination best practise – communication networks and media;

● Inclusion of water sector climate risk reduction modules in local university curricula

5.9 Institutional framework for Project Implementation

The GCF Project's National Implementation Management (NIM) arrangements will be consistent with arrangements successfully-implemented via other adaptation projects in Comoros supported by UNDP. The Implementing Partner (IP) for this project will be the MEAPEATU, which will have project ownership and will appoint a Project Manager (PM), paid for by the project, to coordinate project operations. The main beneficiaries of this project will be the MAPEAU, the Water and Electricity of Comoros Agency (MA-MWE), the local Water Committees of Anjouan and Moheli (UCEM) and (UCEA), Electricity of Anjouan (EDA), the Direction of Meteorology as well as the local Water User Associations and CBOs. The Project Steering Committee, led by MAPEAU, will be responsible for approving program activities. Based on the approved activities, the Project Management Unit (PMU) will ensure the provision of funds to all institutions/organizations for their respective activities. All executing agencies will be responsible for managing tasks allocated to their institution/organization. The UNDP Comoros Programme Officer will be responsible for Project Assurance.

The Project Steering Committee (PSC) established by a Ministerial Order will be directed by MAPEAU and will be responsible for approving reports and activities. It will also provide guidance for proper implementation of the project. Members of the Project Steering Committee will include UNDP, representatives from the Ministries of Environment, Economy, Transport, Health and Interior as well as MA-MWE, UCEA, UCEM and EDA. The PSC will be responsible for making management decisions for the project, in particular when guidance is required by the PMU. The PSC plays a critical role in project monitoring and evaluation by quality-assuring processes and products and using evaluations for performance improvement, accountability and learning. The Committee will convene 2 times per year. Representatives from other institutions/organizations such as local Water User Associations can be included in the PSC as appropriate.

The Project Manager has the authority to run the project on a day-to-day basis. The PM is accountable to UNDP, the IP and the PSC for the quality, timeliness and effectiveness of the activities carried out, as well as for the use of funds. He/she will also be responsible for coordinating budgets and work plans at the island level with the Island Coordinators. The PM will be assisted by a Chief Technical Advisor, a Procurement Officer and a Financial and Administrative Assistant. Three technical committees, one from each island will provide financial and technical support to the PMU.

138

Figure 3738: Project organisation structure organogram

139

5.10 Institutions at national and state levels

140

Table 23: Table of stakeholders

5.11 Stakeholder and Community Engagement

A series of tri-partite full project document design and consultation meetings has been undertaken since July 2016 between UNDP, government stakeholders and the consultant design team. These included a review of the Concept Note design in July 2016, discussions on the roles of different water-related agencies and a series of national workshops on the target zones to be selected involving more than 30 agency representatives.

Meeting minutes and agency attendance records are held in Annex 10 - Consultation, Meeting and Engagement Documents, confirming the involvement and engagement of the country’s water related stakeholders in the design process.

In early 2017, environmental impact assessment and socio-economic impact assessment of the detailed design were undertaken and included additional consultation with the proposed national and island agencies to be involved with implementation as well as consultations with beneficiary communities (see Annex 10 - Consultation, Meeting and Engagement Documents).

In May 2017 community visits were undertaken by the national design consultants on all three islands and discussions held with the local communities on likely requirements for land access, land occupation and land disturbance and potential vegetation loss.

All communities were asked to confirm their agreement to the project activities being undertaken on land within the community ownership and control. The signed agreements are held in Annex 10 - Consultation, Meeting and Engagement Documents with selected photographic records of these community consultations.

5.12 Operation and Maintenance Plan for Water Supply

As discussed in the engagement plan and stakeholder consultations of the project, the Operation and Maintenance (O&M) Plan describes the activities needed and provides a framework for monitoring by the organizations and stakeholders of the defined output and activities in the different islands. Further elaboration of the O&M plan and the roles and responsibilities of key is provided within FP Annex XIII (b).

The organizational structures, needed to systematically support O&M of the water sector are described as follows:

1. The organizational structures of the water sector

a) National Director of Water – provides oversight of the water sector at national level.b) Regional Water Director – ensures necessary technical information for plans, studies and annual reports

of operational efficiency are managed.

2. Water infrastructure management by MaMwe-SOGEM and all operators delegated by the respective municipalities – perform day to day operations and maintenance of water production and treatment, including direct customer engagement for information and billing.

141

a. UCEA / UCEM (Union des Comités d’Eau Anjouan/Union des Comités d’Eau Mohéli) - These farm organizational structures will generally be responsible for the villages.

b. Water Management Committees – manage the water sector in rural and remote areas. In order to carry out their tasks, the Water Committees (CEMs) to employ paid staff (operations officer / recovery officer)and to implement the preventive maintenance program prepared at the UCE level with the support of DREA

c. Rural Centers for Economic Development -CRDE - These centers will ensure better support for farmers/growers in the most vulnerable areas;

d. Technical Department of Meteorology – provides national water resources information database and provides users with guidance notes. National report development, management and archiving of agro & hydro meteorological data in digital and paper formats;

Some of the key operation and maintenance activities to be carried out the designated water authority includes:

Zones Responsible Party Types of Intervention

Zone 1 The National Water and Electricity Company, MaMwe

- Well maintenance and drilling;- Maintenance of submerged pumps;- Maintenance of the tanks;- Maintenance of the AEP network;- Maintenance of EkoTanks by CRDE Zone

Zone 2 Water Management Committee OR a private operator delegated by the Commune / Mairie de Ngongwe

- Well maintenance and drilling;- Maintenance of submerged pumps;- Maintenance of the tanks;- Maintenance of the AEP network;

Zone 3 Water Management Networks Committee OR a private operator delegated by the Commune / Ngongwe Town Hall

- Well and boreholes maintenance and drilling;- Maintenance of submerged pumps;- Maintenance of the tanks /impluviums and micro-basin;- Maintenance of the AEP network;

Zone 4 Water Management Networks Committee OR a private operator delegated by the Commune / Mairie de Boikou


142

Zone 5 Water Management Networks Committee OR a private operator delegated by the Commune / Oichili City Council


Zone 6 Water Management Networks Committee OR a private operator delegated by the Commune / Hamanvou Municipality

- Maintenance of impluviums;- Maintenance of supply lines to micro-basins;- Maintenance of the tanks /impluviums and micro-basin;- Maintenance of irrigation works;- Maintenance of the AEP network;

The Rural Centers for Economic Development (CRDE)

- Maintenance of impluviums;- Maintenance of supply lines to micro-basins;- Maintenance of micro-basins and troughs;- Maintenance of irrigation works;- Maintenance of Automatic Rainfall Stations, DOPPLER Rain Radar, Piezometric Measurement Equipment / Aquifer Salinity

Zone 7

Water Management Committee OR a private operator delegated by the Commune / Mairie

- Maintenance of water collection;- Maintenance of supply lines to tanks and treatment units;- Maintenance of treatment units;


- Maintenance of supply lines to micro basin and collective waterers;- Maintenance of supply lines to micro-basins;- Maintenance of irrigation networks

Zone 8; Zone 9 ; Zone 10 ; Zone 11; Zone 12 ; Zone 13 ;

Water Management Committee OR a private operator delegated by the Commune / Mairie respectively of the zone

- Maintenance of water collection;- Maintenance of supply lines to tanks and treatment units;- Maintenance of treatment units;

143

Zone 14 ; Zone 15


- Maintenance of supply lines to micro basin and collective waterers;- Maintenance of supply lines to micro-basins;- Maintenance of irrigation networks.

* AEP Network - Water distribution network (pipes, valves, flow meters etc.)

Maintenance and maintenance costs

Over the next twenty years, the Union of Comoros Government will bear the cost of the Operation and Maintenance. All supply and access to water will be anchored in a tariff-based model that will engender ownership and commitment to securing drinking water for households and other users.

Annual project operation and maintenance costs for 25 years

The cost of the operation and maintenance (Budget included in FP Annex XIII (b) includes the costs of the corrective and preventive interventions necessary to maintain the infrastructure (labour and / or equipment) at the necessary operating levels. It also includes all logistical costs required for maintenance operations as well as overhead and administration costs attributable.

The Operation and Maintenance comprise of the following:

● Labor cost of intervention: time spent x hourly rate

● Overhead costs of the maintenance function (indirect labor, energy, tools, etc.)

● Cost of Possessing Spare Stocks

● Consumption of spare articles (purchase, transport, ordering)

● Flat-rate maintenance contracts (partly dependent of the number of foreign or local interventions

necessary)

● Subcontracted work on interventions (fixed or unit price contracts to control expenditure)

CONCLUSIONS

Comoros is one of the most vulnerable countries in the word to climate change due to natural vulnerability as a SIDS (i.e. little land mass and fragile freshwater resources), combined with weak adaptation capacity given its limited financial resources and technical capacities for adaptation as a SIDS, LDC and as well as an African state.

This is recognised in the country positions statements and policies on climate change, with water security the highest priority.

144

Baseline studies show climate change to already be occurring in Comoros with increasingly frequent and intense dry seasons and storm events being demonstrated in the rainfall record as well as observed in-country.

Global Climate Models predict increases in drought duration of up to 48 days, increases in wet season rainfall of up to 45%, increases in storm event rainfall of 34%, resulting in at least equivalent increases in storm flows, and increasing watershed erosion not only by 2 orders of magnitude but permanently destabilizing the catchments.

The existing water supply performance is consistent with that achievable in other LDC SIDS and functions adequately during periods of operational norms and usual weather patterns. Recent dry seasons as well as catastrophic flooding events in the last decade demonstrate the water supply systems can just cope with increase in existing climatic risks, but only using ad hoc resilience strategies.

The forecast increase in climate variability will move these water supply systems from a position of just coping to one of failure, both during the predicted extended dry periods and the predicted increased intensity, frequency and destructive potential of storm events. It is therefore urgent that assistance is required under the GCF to deliver a paradigm shift to the country to achieve a climate resilience of the water sector.

The recently approved (but yet to be enacted) national water sector governance reforms provide an ideal opportunity to utilise an on-going water sector wide reform process to include mainstream and integrate climate change adaptation approaches across the entire water sector – achieving a paradigm shift in climate risk reduction. This opportunity is however time-constrained and limited to the next few years during which these reforms will be delivered.

Based on the comprehensive findings of technical feasibility studies, the Proposed Project contains three main strategies:

● Integrating climate change adaptation into the national, island and community water governance

arrangements including tariff systems to sustain climate resilient water supply infrastructure, and develop water service provider technical capacity to use drinking water risk reduction approaches to minimise future climate risks;

● Investigation and monitoring of the nation’s water resources during climatic extremes to understand

climate risk impacts on security of water supply and develop and use climate forecasting linked to adaptation preparedness and response tools to build adaptive capacity of water users, including using watershed eco-system based adaptation management to protect and improve dry season flows and reduce flood risks and storm flow erosion derogated water quality; and

● Upgrade climate resilience of existing drinking water supply schemes to drought and flood risks, including

increasing access to multiple water sources as well as improving irrigation systems, and use of water efficiency measures. This includes utilizing the Operations and Maintenance plan with supporting updated SOP practices to ensure long term sustainability of the infrastructure.

The project will pursue to create an enabling environment aiming to promote the sustainability for water supply management resilience, implementing concrete water mobilization works and in protecting water sources. This will be done through the following elements:

145

● Institutional Sustainability – Legal Requirements, Capacity and Tariffs: Climate change risk reduction will be included in the national water legislation which will require evaluation and minimization of climate risks in all agency and organization planning and design.

● Financial Sustainability – Tariffs and Legal Requirements: In the medium term a water tariff will be introduced that provides adequate cost recovery to enable water supply providers to have sufficient budgets for not only addressing operation & maintenance during climatic extremes but also where necessary capital re-investment of infrastructure. Projected operations and maintenance costs have been developed to better budget and plan for long term sustainable infrastructure.

● Environmental Sustainability – Water and Land Resources Protected Exploitation: The GCF project will contribute to a greater physical understanding of water resources. This understanding will support climate-informed water management to ensure sources will not be impacted by saltwater intrusion or sedimentation caused by intense rainfall events.

● Technical Sustainability – Capacity Building: The Project includes technical training aiming to build long-term, continued capacities across the agencies capacity and empower women to address their specific vulnerabilities to climate change and water management.

● Social Sustainability - Participative Approach : The project, through enforcement of the reformed Water Code and the Decentralization Strategy of the Comoros will ensure participation with existing Water User Associations and Women’s Groups to create sustainable and fair water tariff scheme and equitable water supply schemes. To ensure sustainability of the water management system, user behavior change will be promoted with respect to protection and conservation of water services

The project will benefit more than 50% of the country population directly (450,000) with infrastructure support and the entire population (800,000) through establishing a sustainable climate resilient water sector enabling environment, national water resources monitoring and climate risk forecasting.

146

REFERENCES

1. Abdou, Soimadou, Etude de vulnérabilité dans le secteur forestier, 2015.

2. AEP (Adduction en Eau Potable) Sima and Domoni (Anjouan) and AEP Djandro (Moheli).

3. AEPA Project 2013, Etudies Techniques, du Cadre Institutionnel Et Du Programme National D’AEPA.

4. Acclimate (2011). Étude de vulnérabilité aux changements climatiques. Evaluation qualitative. Union des Comores, 93p.

5. African Development Bank Group Union of the Comoros Country Strategy Paper 2016-2020.

6. African Development Bank, Strategy and Programme of PEAPA in Comoros: Socio-economic context.

7. African Development Bank, Strategy and Programme of PEAPA in the Comoros: Hydrologic and water resources balance,: Hydrogeologic context, Socio-economic context,: Water resources monitoring

8. ANWADHUI Mansourou 2012. Vulnerability Evaluation on Flood Risks in the Comoros Islands. UN Report. Environment Programme / Reduction of Risks and Catastrophes

9. Asconit Consultants, March 2011. Indian Ocean Commission. FFEM. French Republic. Vulnerability to Climate Change Study: Qualitative Evaluation. Comoros National Report.

10. Bachery P et al 2016. Structure and Eruptive History of Karthala Volcano.

11. Charmoullie, 2012. Ebauche du fonctionnement hydrogeologique de l’ile d’Anjouan (Comores)

12. Comoros’s Initial National Communication to the UNFCCC 2001.

13. Commission de L’Ocean Indien. 2012. Synthese des travaux du projet Acclimate.

14. Diagnostic approfondi de la ressource en eau pour approvisionnement des iles comores, Version definitive – Avril 2016.

15. DGEF, UNDP, GEF April 2012. Report on the Vulnerability and the Adaptation of Water Resources at Risk to Climate Change Impacts on Anjouan.

16. Dernier Rapport d’évaluation, Gestion Durable des Terres, 23 mars 2014 ; 2ème communication nationale

17. Données brutes du service statistique de la DRSA, 2012

18. ECDD, BCSF & Durell (Feb 2014). Land Cover Mapping of the Comoros Islands: Methods and Results. Lead Author: Katie Green.

19. ECEM, 2008. Schema Directeur pour ‘approvisionnement en Eau des populations de la region de Djandro.

20. Élaboration d’une stratégie sectorielle nationale – Énergie aux Comores. AETS Consortium. 2013

21. Elaboration d’une stratégie sectorielle nationale Energie aux Comores (Document 2.2 Stratégie sectorielle à 20 ans, Rapport final, 2013) ; FAO, Appui au programme forestier national, 2009

22. Etude techniques du cadre institutionel et de programme national d’AEPA, Mars 2013.

23. FRA 2010: http://www.fao.org/docrep/013/i1757f.pdf

24. FRA 2015 for comoros: http://www.fao.org/3/a-az188f.pdf

25. Ganasri, B.P. and Ramesh, H., 2016. Assessment of soil erosion by RUSLE model using remote sensing and GIS-A case study of Nethravathi Basin. Geoscience Frontiers, 7(6), pp.953-961.

26. Initial National Communication, 2002

147

27. Intergovernmental Panel on Climate Change. 2001. Technical Summary. Pp 21-23. IN: Houghton, J., Ding, Y., Griggs, D., Noguer, M., Van Der Linden, P., Dai, X., Maskell, K., Johnson, C., eds. Climate Change 2001: The Scientific Basis. Published for the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom, and New York, NY, USA, 881 pp

28. IWRM Road Map for the Comoros 2015.

29. Jean-Christophe Comte et. al, Challenges in groundwater resource management in coastal aquifers of East Africa: Investigations and lessons learnt in the Comoros Islands, Kenya and Tanzania, Journal of Hydrology: Regional Studies 5, pp. 179–199 (2016)Karnauskas, K. B., 2017. Report on Climate Change Projections for the Republic of Marshall Islands.

30. Le Quéré, C., Andrew, R.M., Canadell, J.G., Sitch, S., Korsbakken, J.I., Peters, G.P., Manning, A.C., Boden, T.A., Tans, P.P., Houghton, R.A. and Keeling, R.F., 2016. Global carbon budget 2016. Earth System Science Data, 8(2), pp.605-649.

31. Mansourou, A., 2013, Contribution à la gestion des risques de catastrophes naturelles: cas des inondations aux Comores, Université Senghor

32. C. McSweeney, M. New and G. Lizcano, UNDP Climate Change Country Profiles Comoros

33. Morin J et al 2016. Volcanic Risk and Crisis Management on Grand Comore Island.

34. Moss, R.H., Edmonds, J.A., Hibbard, K.A., Manning, M.R., Rose, S.K., Van Vuuren, D.P., Carter, T.R., Emori, S., Kainuma, M., Kram, T. and Meehl, G.A., 2010. The next generation of scenarios for climate change research and assessment. Nature, 463(7282), p.747.MP2L, 2015. Schema Directeur AEP Mbadjini Est.

35. NAPA, 2006

36. National Progress Report on MGGs (2012)

37. Perspectives économiques en Afrique 2016, VILLES DURABLESET TRANSFORMATION STRUCTURELLE, Banque africaine de développement, Organisation de coopération et de développement économiques, Programme des Nations Unies pour le développement (2016)

38. Peter Gleick “The Human Right to Water”, Water Policy, Elsevier Science (1999) pp. 487-503

39. PFS – Pre-feasibility study: Diagnostic Approfondi de la resource en eau pour approvisionnement des iles Comores, Avril 2016.

40. Plan d’Aménagement de la Zone Bandasamlini-Sangani-Diboini, 2013. Plan d’aménagement de la région de Nioumakélé-bas, 2013

41. Plan d’action Forestier, 2011, Gouvernement des Comores.

42. Plan d’Action Forestier, 2012.

43. Raphael Tshimanga, 2015. Mutsumudu Watershed Integrated Management Plan. UNEP IWRM SIDS Programme.

44. Rapport national COMORES: Etude vulnérabilité, 2011

45. Rapport National sur le Développement Humain-Insécurité alimentaire et vulnérabilité, 2003-2004 (Union des Comores/ SICIAV/FAO/UNDP, page 29).

46. Rapport National sur le vulnérabilité et l’adaptation sur les ressources en eau face aux changements climatiques sur l’ile d’Anjouan

47. Rapport sur le suivi et l’application de la strategie de Maurice, Novembre 2009

48. 5ème rapport national sur la diversité biologique des Comores, Juin 2014

49. Recensement général de la population et de l'habitat, 2003148

50. Renard, K.G., Foster, G.R., Weesies, G.A. and Porter, J.P., 1991. RUSLE: Revised universal soil loss equation. Journal of soil and Water Conservation, 46(1), pp.30-33.

51. Renard, K.G. and Freimund, J.R., 1994. Using monthly precipitation data to estimate the R-factor in the revised USLE. Journal of hydrology, 157(1-4), pp.287-306.

52. Seconde Communication Nationale sur les Changements Climatiques, 2012.

53. Stratégie de croissance accélérée et de développement durable 2015-2019 (SCA2D) (May 2014)

54. Stratégie et Programme d’AEPA aux Comores (2013): Contexte socio-économique de l’AEPA.

55. Strategie et programme National d’AEPA des Comores.

56. Socio-economic Assessment Oct 2016

57. Taylor, K.E., Stouffer, R.J. and Meehl, G.A., 2012. An overview of CMIP5 and the experiment design. Bulletin of the American Meteorological Society, 93(4), pp.485-498.

58. Tshimanga, R.M., CB-Hydronet, Kinshasa, RDC, Sep 2015. Implementing Integrated Water Resources and Wastewater Management in Atlantic and Indian Ocean Small Island Developing States. Integrated Water Resources and Wastewater Management in Atlantic and Indian Ocean Small Island Developing States. IWRM Demonstration Project, Anjouan, Union of Comoros. Integrated Water Management Plan for Mutsamudu.

59. Union des Comores – Strategie de croissance acceleree et de developmmement durable (SCA2D), 2015-2019.

60. UNEP Project Document : Building Climate Resilience through Rehabilitated Watersheds, Forests and Adaptive Livelihoods, PMS 5694.

61. UNEP, 2002, “Atlas des ressources côtières”

62. United Nations Res/69/15. SIDS Accelerated Modalities of Action (SAMOA) Pathway.

63. Watershed management field manual, T C Sheng, FAO, 1990.

64. World Bank, 2017. Metadata of the Climate Change Knowledge Portal.

65. http://sdwebx.worldbank.org/climateportal/ (Last accessed: March 2018)

66. www.afdb.org/en/news-and-events/article/tackling-the-challenges-of-the-current-energy-crisis-in-the- comoros-14078/

67. www.cepf.net/where_we_work/regions/africa/madagascar

68. https://www.cia.gov/library/publications/the-world-factbook/geos/cn.html .

69. http://data.worldbank.org/country/comoros

70. www.ecddcomoros.org/comoros/biodiversity/

71. www.ecddcomoros.org/comoros/history .

72. http://www.ifdd.francophonie.org/reseaux/hydro_quebec/pays_et_entreprises/afrique/comores/ comores.html

73. http://www.itfc-idb.org/en/content/itfc-partners-comoros-supporting-its-energy-sector

74. www.lemonde.fr/societe/article/2017/02/10/mayotte-touchee-par-une-penurie-d-eau-depuis-plus-de- deux-mois_5078001_3224.html

75. http://www.pwwa.ws/index.php?page=Benchmarking2 .

76. http://www.tradingeconomics.com/

149

77. http://unfccc.int/resource/docs/napa/com01e.pdf .

78. http:///www.worldbank.org/en/country/comoros/overview .

150