Japan International Cooperation Agency (JICA)
Oromia Irrigation Development Authority (OIDA)
Small Scale Irrigation
Water Management Guideline
May, 2014
The Project for Capacity Building in Irrigation Development (CBID)
Foreword Oromia Irrigation Development Authority (OIDA) is established on June, 2013, as a responsible body for all irrigation development activities in the Region, according to Oromia National Regional Government proclamation No. 180/2005. The major purposes of the establishment are to accelerate irrigation development in the Region, utilize limited resources efficiently, coordinate all irrigation development activities under one institution with more efficiency and effectiveness. To improve irrigation development activities in the Region, the previous Oromia Water Mineral and Energy Bureau entered into an agreement with Japan International Cooperation Agency (JICA) for “The Project for Capacity Building in Irrigation Development (CBID)” since June, 2009 until May, 2014. CBID put much effort to capacitate Irrigation experts in Oromia Region through several activities and finally made fruitful results for irrigation development. Accordingly, irrigation projects are constructed and rehabilitated based on that several Guidelines & Manuals and texts produced which can result in a radical change when implemented properly. Herewith this massage, I emphasize that from Now on, OIDA to make efforts to utilize all outputs of the project for all irrigation activities as a minimum standard, especially for the enhancement of irrigation technical capacity. I believe that all OIDA irrigation experts work very hard with their respective disciplines using CBID outputs to improve the life standard of all people. In addition, I encourage that all other Ethiopian regions to benefit from the outputs. Finally, I would like to thank the Japanese Government, JICA Ethiopia Office, and all Japanese and Ethiopian experts who made great effort to produce these outputs.
Feyisa Asefa Adugna
General Manager
Oromia Irrigation Development Authority
Addis Ababa, Ethiopia May, 2014
Introductory Remarks
“Growth and Transformation Plan” (GTP) from 2011 to 2015 intensifies use of the country’s water and other natural resources to promote multiple cropping, better adaptation to climate variability and ensure food security. Expansion of small scale irrigation schemes is given a priority, while attention is also given to medium and large scale irrigation.
In Oromia Region, it is estimated that there exists more than 1.7 million ha of land suitable for irrigation development. However, only 800,000 ha is under irrigation through Traditional and Modern irrigation technology. To accelerate speed of Irrigation Development, the Oromia National Regional State requested Japan International Cooperation Agency (JICA) for support on capacity building of Irrigation Experts under Irrigation Sector.
In response to the requests, JICA had conducted "Study on Meki Irrigation and Rural Development" (from September 2000 to January 2002) and Project for Irrigation Farming Improvement (IFI project) (from September 2005 to August 2008). After implementation of them there are needs to improve situation on irrigation sector in Oromia Region.
JICA and the Government of Ethiopia agreed to implement a new project, named “The project for Capacity Building in Irrigation Development” (CBID). The period of CBID is five years since June, 2009 to May, 2014 and main purpose is to enhance capacity of Irrigation Experts in Oromia Region focusing on the following three areas, 1) Water resources planning, 2) Study/Design/Construction management, 3) Scheme management through Training, On the Job Training at site level, Workshops, Field Visit and so on and to produce standard guidelines and manuals for Irrigaiton Development.
These guidelines and manuals (Total: fourteen (14) guidelines and manuals) are one of the most important outputs of CBID. They are produced as standards of Irrigation Development in Oromia Region through collecting different experiences and implementation of activities by CBID together with Oromia Irrigation Experts and Japanese Experts.
These guidelines and manuals are very useful to improve the Capacity of OIDA Experts to work more effectively and efficiently and also can accelerate Irrigation Development specially in Oromia Region and generally in the country.
Finally, I strongly demand all Irrigaiton Experts in the region to follow the guidelines and manuals for all steps of Irrigation Development for sustainable development of irrigation.
Adugna Jabessa Shuba
D/General Manager & Head, Study, Design, Contract Administration & Construction Supervision
Oromia Irrigation Development Authority
Addis Ababa, Ethiopia May, 2014
TABLE OF CONTENTS
1 INTRODUCTION ................................................................................. 1
2 DEFINITION ....................................................................................... 1
3 OBJECTIVE ....................................................................................... 2
4 SCOPE ............................................................................................... 2
5 DOCUMENT SETUP ........................................................................... 2
6 IRRIGATION WATER SUPPLY ............................................................. 3
6.1 Irrigation water management ....................................................... 3
6.2 Basics of irrigation water management ........................................ 3
6.3 Irrigation water source ................................................................ 3
6.4 Main components of small scale irrigation ................................... 4
6.5 Irrigation water use right ............................................................. 4
6.6 Water delivery criteria .................................................................. 5
6.7 Abstraction system ...................................................................... 5
6.7.1 Lift abstraction ...................................................................... 6
6.7.2 Headwork .............................................................................. 6
6.8 Canals ......................................................................................... 7
6.8.1 Main canal ............................................................................ 8
6.8.2 Secondary canal .................................................................... 8
6.8.3 Tertiary canal ........................................................................ 8
6.8.4 Field canal ............................................................................ 8
6.9 Flow scheduling at canals ............................................................ 8
6.10Change in water demand ............................................................. 10
7 FIELD IRRIGATION WATER MANAGEMENT ....................................... 11
7.1 Cropping plan and selection of irrigation methods ....................... 11
7.1.1 Crop selection and pattern .................................................... 11
7.1.2 Selection of irrigation method ................................................ 12
7.2 Irrigation systems and methods ................................................... 12
7.2.1 Furrow irrigation ................................................................... 12
7.2.2 Basin irrigation ..................................................................... 14
7.2.3 Drip or Trickle irrigation ........................................................ 15
i
7.3 Crop water requirement (CWR) .................................................... 15
7.3.1 Factors affecting evapotranspiration ...................................... 16
7.3.2 Irrigation water requirement (IWR) ......................................... 18
7.3.3 Methods of determining crop consumptive use of water ......... 18
7.3.4 Gross irrigation water requirement ........................................ 19
7.4 Irrigation scheduling ................................................................... 20
7.4.1 General requirements for irrigation scheduling ...................... 20
7.4.2 Determination of irrigation scheduling ................................... 20
7.5 Principles of scheduling irrigation water ...................................... 23
7.6 Irrigation efficiencies ................................................................... 27
Annex-1 Sensitivity of various field crops to water shortage ................ 30
Annex-2 Periods sensitive to water shortage ....................................... 31
List of Authors/Experts/Editors/Coordinators ....................................... 32
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1 INTRODUCTION
Sustainable Irrigation has crop water supply, irrigation agronomy and
scheme administration, which in turn the scheme administration can be
classified as facility management, operation, water management and
organizational management.
An irrigation which fails to address all the above properly will endanger the
scheme and negatively impacts the environment. Specially, if the water is
not managed properly the impact will be irreversible, salinity can develop,
water logging affects the crops, erosion can impact the plots, and conflicts
can arise between upstream and downstream and also among beneficiaries.
This manual intends if possible to prevent or to minimize the above listed
and other possible damages which can arise from poor irrigation water
management. In addition but also as main objective the manual address the
result of good water management.
2 DEFINITION
In this document Irrigation is defined as the supply of water to agricultural
crops (Plants) by artificial means, designed to permit farming (growing
plants) in moisture stressed areas. The objective of the irrigation process is
to store the applied water by human in the soil reservoir to be used in
succeeding days when the plant needs it.
According to different literature and experience, Irrigation Water
management:
Is timely, fair and efficient distribution of sufficient and necessary
water to the command area.
Is to adjust irrigation water and moisture in the field to optimize crop
cultivation and production.
Includes headwork’s conveyance, regulation measurement,
distribution and application of irrigation water to soil as well as
drainage of excess water.
Is the process of determining and controlling the volume, frequency,
and application rate of irrigation water in planned and efficient
manner.
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From this we can understand that irrigation water management can be seen
from two general perspectives, Irrigation water supply (more of engineering)
and Irrigation water application (more of irrigation agronomy).
3 OBJECTIVE
To improve use, efficiency, particularly, increase the crop productivity per
unit volume of water used in the agricultural sector; and Achieving full
reliability of water supplies and integration of main system operations with
those at the farm level is a prerequisite for efficient water use by farmers.
If irrigation is not well managed it negatively affect the environment. Over
irrigation, poor water management and leaky canals may cause water
logging and drainage problems and which intern can impact health and
result loss of agriculture land.
The objective of this manual is to show for irrigation frontline experts how
good water management can be achieved in an irrigation scheme in
irrigation water supply and irrigation agronomy.
4 SCOPE
The manual is limited only in typical conventional small scale irrigation
experience.
5 DOCUMENT SETUP
The manual has two sections, one engineering or irrigation water supply
section and second section on field irrigation water management.
The first section deals with on irrigation water source, abstraction system,
distribution and related matters, whereas section two explains more on field
water management based on crop water requirement.
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SECTION I:
6 IRRIGATION WATER SUPPLY
6.1 Irrigation water management
Irrigation water management is the practice of conveying water efficiently
from the source and applying to the part of the soil profile that serves as the
root zone, for immediate and subsequent use of crops (plants) in known
amounts and at frequencies calibrated not to waste water and energy,
deplete or pollute crops and/or pose the danger of soil degradation.
Irrigation water management implies the involvement of water users,
farmers’ system operators, extended service departments of irrigation,
drainage and agriculture. The mutual interests of all parties involved, as
well as their interrelationships, interactions and organization are of vital
importance to make efficient use of structural improvements in irrigation
and drainage systems. Research, extension, development work in the social,
economic and institutional areas is also an essential part of water
management.
6.2 Basics of irrigation water management
For any irrigation scheme to attain sound water management two main
criteria’s has to be fulfilled:
1. Irrigation hard wares (facilities) has to be in place
2. Software (systems, organizations or institutions and technologies for
operating and maintaining the facilities) should be established.
As we have explained in the introduction this section focus only on the hard
ware based water management. The software part is discussed on the other
manual (refer to Guidance for Preparation of Operation and Maintenance
Manual).
6.3 Irrigation water source
In general speaking irrigation water source can be classified as:
Surface water
o River or streams
o Stored water
Dam
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Pond
Lakes
Tanker
Ground water
Nonconventional water
o Blue water1
o Desalinated water
6.4 Main components of small scale irrigation
Small scale irrigation can have an abstraction facility (pump, simple intake,
weir), canals (main, secondary, tertiary, field canal) and other irrigation
structures.
6.5 Irrigation water use right
In any irrigation the water management depend upon the water use right of
the country, local area and the beneficiaries. The main water right in many
SSI2 schemes can be described as follows:
1. Natural : This is implemented by one of the following;
Share per unit area (Q ≈ A) –
Engineering controlling system – fixed intake
1 The water in rivers and lakes, groundwater and glacial water reserves are called "blue
water".
2 Small Scale Irrigation
A (ha)
Basic Layout of Small Scale Irrigation
Off takes /Turnout
Division Box
Secondary Canal
Main Canal
Tertiary Weir Field Canal
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Share per person or household irrespective of land owned
No engineering controlling system, only trust and
water control policy
Fixed discharge per unit area
Fixed intake system
2. Fixed volume
Gate can be designed
3. Instantaneous demand – as much as they want
Gate can be designed
4. Conditionality – related to scarcity of water
Gate with locker
5. Duration – the water right can be permanent or temporary
6. Ownership & transferability – water right can be transferred /
sold/ lend or water right cannot be transferred or rented by any
means.
In general there is no single model of water rights that can be recommended
as bullet proof solution, but it is very important first to understand the
water use right of the community.
6.6 Water delivery criteria
Water delivery in irrigation scheme depends on adequacy, reliability, equity
and efficiency. Reliable, equitable and predictable water supply is a
confidence for sustainable irrigation agronomy, if one of these fails, the
farmer will not be encouraged to plant crops.
6.7 Abstraction system
Water for irrigation can be abstracted by gravity or lift systems from
different sources. Gravity abstraction is done directly by diverting the river
water with or without regulating structure based on the elevation difference
between the river bed and the command area. Whereas lift system is an
abstraction of water from the source (river, storage or ground water) using
different lifting devices, such as diesel, benzene, electric, man power or other
energy driven pumps.
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6.7.1 Lift abstraction
Lift abstraction is common when the command area elevation higher than
the source of water, underground, reservoir or river. The commonly known
lifting system for small scale irrigation is engine pump, treadle, rope &
washer and other small pumps can be used for micro irrigation.
6.7.2 Headwork
According to the International Commission on Irrigation and Drainage
(ICID), headworks are defined as ” A collective term for all works (weirs or
diversion dams, head regulators, upstream and downstream river training
works and their related structures) required at intakes of main or principal
canals to divert and control river flows and regulate water supplies”. In this
manual we focus on the gravity system specially weir and simple intakes.
(1) Simple intakes
We call simple intakes structures which have only intakes to the canal
without other complicated structures like sluice gate, aprons and other
structures.
(2) Weir
Weir is a structure constructed across the river to effect local storage and
rise water level locally to divert part or all water in the river to a canal. It can
have an obstruction body across the river, wing (retaining) walls, sluice gate
(s), aprons, and other parts.
A weir is crucial point to start with water management in irrigation. The
intakes of weir are designed to take maximum fixed water which is required
to irrigate the intended irrigation land. It can be regulated based on the
irrigation schedule or demand and the availability of water in the river. Over
or under exploitation of the water at the intake causes water management
crisis at downstream of the river and also among the irrigation users.
Water release at headwork depends on two major things:
1. Availability of water in the river based on the water balance at U/S
and D/S (QA)
2. Demand of water from irrigation (QD)
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Small Scale Irrigation Water Management Guideline
Whenever the first one is positive or excess (considering environmental flow
also) water is available in the river the governing variable will be the second
one.
6.8 Canals
Irrigation Canals are structures whose main functions are to get water
around the scheme up to the field level. Canals can be classified and named
according to the local context, but in general can be classified as conveyance
and distribution canals. Further, it can be classified as primary canal, main
canal, branch, secondary canal, tertiary, quaternary and field canal.
Canals can be rectangular, trapezoidal, semicircular or circular in shape
and also can be earthen, masonry, concrete or geo-membrane lined or other
type. These characteristics of the canal- producing mechanical forces
between the water and walls and the bottom of the canal due to its rubbing
against them and reaction with the weather- can affect the water
management and its efficiency.
According to FAO, Canal conveyance efficencies are expalined as below in
the table:
Soil type Sand Loam ClayCanal length
Long (> 2000m) 60% 70% 80% 95%Medium (200-2000m) 70% 75% 85% 95%Short (< 200m) 80% 85% 90% 95%
Earthen canals Lined canals
Source: FAO, Irrigation Water Management Training manual no. 4 Irrigation scheduling
Remarks: This table is considered as the adequately maintenance level. So, if the
maintenance of the canals is bad, the conveyance efficiency may lower the values
by as much as 50%.
Gates has to function properly (Open – Close), obstructions has to be
removed, leakages must be avoided and water has to be measured
just at the intake for proper distribution.
In most small scale irrigation Main, secondary, tertiary and field
canals are the dominant classification.
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6.8.1 Main canal
Main canal is the main water conveying system of small scale irrigation
system which is responsible for carrying the water directly from the river to
the irrigation system. Sometimes it can feed small canals like tertiary
without secondary. Most of the time main canals recommended being
contour canal for the sake of maximum command area and gentle slope and
minimum structures.
The design and efficiency of main canal is the main decisive variable for
sound water management. In SSI main canals are designed at continuous
flow scenario for full demand flow.
6.8.2 Secondary canal
Secondary canal is a part of conveying and distributing canal based on the
size and length. In SSI it can be classified in distribution canal and can be
designed as continuous or rotation based on the system but it has to be
clear.
6.8.3 Tertiary canal
Tertiary canals the main vein of SSI and the heart of the irrigation water
management. Most of the time, they are managed by nearby beneficiaries.
They are designed most of the time in rotation base.
6.8.4 Field canal
The canals are the blood vein of the irrigation system which feed the furrow.
Most of the water loss in distribution canal is viewed at these canals. They
are fully managed by one or two beneficiaries.
6.9 Flow scheduling at canals
There are three main variables for irrigation scheduling; Frequency, flow
rate and duration. Frequency is how often – time interval-, flow rate is the
amount- quantity -, and duration is time – in second, minutes, etc. -. Based
upon these variables three irrigation forms can be designed for a scheme;
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1. Continuous flow: This type of scenario describes flow is continuous
at all times throughout the system. The governing variable will be
the flow rate.
2. Rotational flow: This scenario is to rotate water coming from the
main or conveying canal among other canals, secondary, tertiary
and field canals.
3. On-demand flow: This can be one of the above or both at different
canals but depend on the demand at delivery point.
Each of the above scenarios has its own merits and de-merits as example
rotation flows requires relatively big size canals, whereas continuous flow
requires small. For effective and efficient water management one has to
understand how the scheme was designed.
Having all these in mind we can say that irrigation schedule can be
generally categorized as;
Rigid schedules
Flexible schedules
Rigid schedules Flexible schedules Constant-amount, constant-frequency Demand Constant-amount, variable-frequency Limited-rate, demand Varied-amount, constant-frequency Arranged (as to date) Limited-rate, arranged Restricted-arranged Fixed-duration, restricted-arranged schedule
The schedule scenario can be selected on the availability of water, crop type,
crop stage, beneficiary consensus or agreement, or scheme administration
authorities decision or by other forms as it sweets to the local condition.
Description for flexible schedule is listed below in table:
No Flexible Schedules Description
1 Demand No restriction on frequency, rate or duration, storage can play big role
2 Limited-rate, demand Flow rate may be restricted, no restriction of frequency or duration.
3 Arranged (as to date) No restriction on frequency, rate or duration but prior request important.
4 Limited-rate, arranged Flow is restricted and prior request is important
5 Restricted-arranged Strict agreement and stick to agreement by the provider and farmer
6 Fixed-duration, restricted-arranged schedule
Duration is fixed, rate & date are arranged.
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6.10 Change in water demand
Water demand change in irrigation can occur due to many reasons, water
scarcity, crop stages, and other reasons. Good irrigation water management
can try to give a solution by;
Manipulating controlling structures – only to release fixed
amount
Adjusting flow duration decrease or increase from/for canal and
also from/for individuals
Exercising deficit irrigation approach
And other agronomical measures
1 2
3 4
Different scenarios of Water conveyance and Distribution
MC- Continuous
TC- Rotation
FC- Rotation
MC- Continuous
TC- Rotation
FC- Rotation
MC- Continuous
TC- Continuous
FC- Continuous
MC- Continuous
TC- Continuous
FC- Rotation
SC- Continuous SC- Rotation
SC- Continuous SC- Continuous
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SECTION 2:
7 FIELD IRRIGATION WATER MANAGEMENT
Irrigation can help to ensure stable production. It raises the yields of specific
crops, and prolongs the effective crop-growing period in areas with dry
seasons, thus permitting multiple cropping (two or more crops per year). The
end use of irrigation production is to sustain food self-sufficiency or to solve
the problem of food insecurity and to make commercial crops for markets.
7.1 Cropping plan and selection of irrigation methods
In general, irrigation is the application of water to the soil for any number of
the following purposes:
To add water to soil to supply the moisture essential for plant
growth
To provide crop insurance against short duration droughts
To cool the soil and atmosphere, thereby making more favorable
environment for plant growth
To reduce the hazard of frost
To wash out or dilute salts in the soil
To soften tillage
7.1.1 Crop selection and pattern
A) Physical factors - (Climatic factors (temperature, rainfall, frost)
Length of Growing Period (LGP)
Land quality- (Topography particularly slope of the land as it affects
drainage and influences soil and water management practices ,Soil
depth and fertility
Water resource (quantity and quality)
B) Socioeconomics - (Preference of beneficiaries, Market availability and
Experience of users)
Once the crops are selected, one can determine the seasonal cropping
pattern and prepare cropping calendar for each crop considering the crop
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rotation requirements. The time needed for land preparation and for harvest
should not be included.
7.1.2 Selection of irrigation method
Each irrigation method has advantages and disadvantages that should be
taken into consideration when choosing the most suitable method. The
factors influencing selection of the type of irrigation methods are natural
conditions (land slope, soil type, field shape, water quantity); types of crops
grown; farmer's previous experience; and capital and operation cost. The
objectives of selecting good method are:
Adequate amount of water should be stored in the root zone
Ensure uniform application of water on the land
Should not cause soil erosion
Efficient (minimum wastage of water)
Maximum land availability for cultivation (less waste land)
Ease surface drainage after irrigation
Minimize salt problem, water logging problems
Fit to the land boundary
Less costly
7.2 Irrigation systems and methods
Most common irrigation methods
Surface Irrigation: (Furrow, basin, boarder irrigation)
Sprinkler Irrigation:- Applying water under pressure
Drip or Trickle Irrigation:- Applying water slowly to the soil ideally at
the same rate with crop consumption
7.2.1 Furrow irrigation
This is the most widely used method for row crops such as vegetables,
cotton, sugar beet, potatoes and orchards. It is usually practiced on gently
sloping land and in most types of soil except those, which are permeable
and easily erodible. Flow in furrows must avoid too fast water advance that
create excessive runoff losses, or too slow advance which induces excessive
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infiltration in the upper part of the field. Short blocked furrows with
manually controlled water applications are practiced by traditional irrigators
in third world while Long and precisely leveled furrows with automated or
semi-automated control are popular in developed countries.
Furrow irrigation is one in which the entire plot is not flooded. The wetted
area ranges from 20-50% of the plot unlike other irrigation methods. This
enables to reduce the evaporation losses and increase the water application
efficiency. A tail channel is made to collect excess tail water and used for
reuse at lower levels. On the basis of the alignment, the furrow may be
classified into two: straight furrow and contour furrow.
The straight furrows are aligned along more or less parallel straight lines
laid along the general slope of the land. This is used in fields relatively flat
(<=0.75%).
Contour furrows, are aligned across the general slope of the land along the
contour. It is used when the slope of the land is relatively steep. Furrows
Irrigation depends on Shape and spacing of furrows, the advance furrow
stream, Field slope, Furrow length, Field width and Cut-back stream.
Furrow length: Furrow length depends on soil type, stream size, irrigation
depth and land slope and ranges from 30 to 300 m or more but farm (or
field) size and shape put practical limits on furrow length.
Shape: The shape of furrows depends largely on slope of the land, and soil
type although type of crops (depth) and spacing influences it: the larger the
slope the broader the furrow in order to increase the wetted soil area.
Furrows are generally V-shaped with the top width varying from 24 - 40 cm
and depth from 15-30 cm. Generally, furrow shape is wide and shallow on
clay soils and narrow and deep on sandy soils.
Slope: Furrows should have a uniform longitudinal slope between 0.05 and
2 percent for drainage and minimizing soil erosion respectively.
Furrow spacing: The spacing of furrows depends mainly on the type of
soils as the latter influences the wetting pattern. Sandier soils have almost
vertical wetting pattern while clay soils have both vertical and lateral wetting
patterns. Hence, sandier soils should have closer furrow spacing than clay
soils. Furrow spacing also depends on type of crops to be planted. In
general, furrow spacing varies from 0.3 to 1.8 with the commonly used
spacing being 0.5 m on sandy soils and 1.2 m on clay soils.
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Most crops grown by furrow irrigation are (Vegetables, cotton, sugarcane
and sugar beet and for orchards and vineyards). When there is water
shortage, irrigation can be applied by using alternative “furrow irrigation”
Furrow irrigation in Ketar Irrigation Scheme, Arsi Zone
7.2.2 Basin irrigation
In basin irrigation, water is flooded in wider areas. It is ideal for irrigating
rice.
The area is normally flat. In basin irrigation, a very high stream size is
introduced into the basin so that rapid movement of water is obtained.
Water does not infiltrate a lot initially. At the end, a bond is put and water
can pond the field. The opportunity time difference between the upward and
the downward ends are reduced. Most crops are grown in basin including
field and orchard crops.
Basin irrigation
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7.2.3 Drip or Trickle irrigation
In Drip or Trickle irrigation system the Water is applied directly to the crop
i.e. entire field is not wetted, but the Water is conserved. Weeds are
controlled because only the places getting water can grow weeds. There is a
slow rate of water application somewhat matching the consumptive use. The
application rate mostly less than soil infiltration rate and there is no need
for a drainage system.
Drip irrigation
7.3 Crop water requirement (CWR)
It is the amount of water required by the plant to fulfil its consumptive use
and is expressed in mm/day. An important element in the introduction of
effective water use technologies will be the timely supply of water in the right
Pipes
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quantities to famers. It is an adequate knowledge of crop water use and
irrigation requirements for the various crops in the given climatic condition
will be essential in the planning, implementation and monitoring of
irrigation demonstration.
The irrigation requirement determine for specific crop is not universally
applicable to a variety of environmental condition. Even within a given and
or semi arid zone, the variation in climatic condition are so great that
difference evapotranspiration are appreciable. Under the same climatic
conditions different crops requires different amount of water and quantity of
water used by particular crop variety with its stage of growth.
Initially during seeding, sprouting and early growth a crop uses water at a
relative slow rate. The rate will increase with growth of crop reaching the
maximum in most crops as it approaches flowering and then decline
towards maturity. Evapotranspiration or consumption use is the amount of
water evaporate from the soil and the amount of water transpired by the
crop.
7.3.1 Factors affecting evapotranspiration
(1) Climatic Factors Influencing Evapotranspiration
Temperature, Solar radiation and Wind
A certain crop grown in a sunny and hot climate needs more water than the
same crop grown in a cloudy and cooler humid climate. There are however,
apart from sunshine and temperature, other climatic factors, which
influence crop water needs. These factors are the humidity and wind speed.
When it is dry the crop water needs are higher than when it is humid. In
windy climates the crop uses more water than in calm climates.
The value of Kc largely depends on the types of crops grown /as annual and
perennial/, their growing stages, level of ground cover, root depth and their
total growing period etc. For most crops, Kc increases from a low value (0.5–
0.9) during the initial stages of growth, to a maximum value (0.9–1.2) during
the period when the crop reaches full development, and declines again (0.3–
0.9) as the crop matures. This is true for most annual crops. Once the total
growing period is known, then the duration of the various stages of growth
of a given crop can be determined. The crop growing period, in general is
divided into four stages:
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initial stage , crop development stage , mid- season stage and late-
season stage
Description the four crop growth stages
Crop growth stage Description
Initial stage Germination and early growth, little of the soil (less than 10%) is covered with crop.
Crop development Up to when the crop achieves full ground cover.
Mid-season From full cover is achieved to maturity, when leaves start to dis-colour or fall off. Flowering and fruit setting occurs during this phase.
Late-season From mid-season until harvest.
Crop Coefficient (Kc)
Crops Initial Crop
development Mid-
season Late & harvest
Depth of Root system
(cm)
Depletion level (%)
Seasonal
Bean (dry) 0.35 (20)
0.70(30)
1.00(40)
0.90(20)
50-70 0.45
Cabbage 0.45 (20)
0.75(25)
1.05(60)
0.90(15)
40-50 0.45
Carrot 0.45 (20)
0.75(30)
1.05(30)
0.90(20)
50-100 0.35
Cotton 0.45 (30)
0.75(50)
1.15(55)
0.75(45)
100-170 0.65
Cucumber 0.45 0.7 0.90 0.75 70-120 0.50
Groundnut 0.45 (25)
(35)
1.00 (50)
0.75 (20)
50-100 0.40
Lettuce 0.45 (20)
0.60(30)
1.00(15)
0.90(10)
30-50 0.30
Maize 0.40 (20)
0.75(35)
1.15(40)
0.75(30)
100-200 0.60
Onion 0.50 (20)
0.75(45)
1.05(20)
0.85(10)
30-50 0.25
Pea 0.45 (20)
0.80(25)
1.15(35)
1.05(15)
60-100 0.35
Pepper 0.35 (30)
0.75(35)
1.05(40)
0.90(20)
50-100 0.25
Potato 0.45 (25)
0.75(30)
1.15(30)
0.75(20)
40-60 0.25
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Crops Initial Crop
development Mid-
season Late & harvest
Depth of Root system
(cm)
Depletion level (%)
Sorghum 0.35 (20)
0.75 (30)
1.11 (40)
0.65 (30)
100-200 0.55
Sugar beet 0.45 (25)
0.80(45)
1.15(60)
0.80(45)
70-120 0.50
Tomato 0.45 (25)
0.75(40)
1.15(40)
0.80(25)
70-150 0.40
Wheat 0.35 (15)
0.75(30)
1.15(65)
0.70(40)
100-150 0.55
Permanent Young Mature Alfalfa 0.35 0.85 100-200 Banana 0.50 1.1 50-90 Citrus 0.30 0.65 120-150
Sugar cane 0.45-0.85
1.15-0.65 120-200
Source: FAO I & D paper 24 (1977) and I & D 33 (1979)
Remarks: ( ) shows the number of days for each crop growth stage.
7.3.2 Irrigation water requirement (IWR)
IWR is the water that must be supplied through the irrigation system to
ensure that the crop receives its full crop water requirement. For
Complementary irrigation, IWR >= CWR while IWR < CWR for
supplementary irrigation.
7.3.3 Methods of determining crop consumptive use of water
There are various methods adopted for determining crop consumptive use of
water. These are broadly classified under: -
Direct measurement
Use of Empirical formula
The Empirical formula approached broadly attempts to estimate reference
evapotranspiration (ETo) by empirical method from climatic data (solar
radiation, humidity, wind speed and temperature). Most commonly used
methods are:
Pan evaporation method;- The pan method makes use of the evaporation
data (Epan) which is measured with evaporation pan.
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Blaney-Criddle method;- This method is suggested for areas where only air
temperature and general levels of relative humidity, sunshine hours and
wind speed are available and is recommended for periods of one month or
longer.
Penman method:- Penman-Monteith method is considered to be the most
accurate method for estimating ETo but it requires relatively more data than
others. The method is considered to offer the best results with minimum
possible error in relation to a living grass reference. ETo values that are
more consistent with actual crop water use data in all regions and climates.
7.3.4 Gross irrigation water requirement
The gross irrigation requirements account for losses of water incurred
during conveyance and application to the field. This is expressed in terms of
efficiencies when calculating project gross irrigation requirements from net
irrigation requirements as shown below:
Gross irrigation water depth (GIR) = E
NIR
Where, E = Irrigation efficiency
There are three basic irrigation efficiency concepts. These are:
Conveyance efficiency (Ec) = Water received at inlet to block of fields Water released from the headwork
Distribution efficiencies(Ed) = Water received at field inlet Water received at inlet to block of fields
Application efficiency (Ea) = Water stored in the root zone Water received at field inlet
Project efficiency (E) = Ec × Ed× Ea
Typical Surface Irrigation Efficiencies
Description %
Conveyance efficiency (Ec) 65 - 90 Field canal efficiency (Eb) 70 - 90 Distribution efficiency (Ed = Ec.Eb) 30 - 65 Application efficiency (Ea) 40 - 50 Project efficiency (E) 30 - 40
Assume/select application efficiency of 50%.
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7.4 Irrigation scheduling
7.4.1 General requirements for irrigation scheduling
At the end of this lesson, the following questions can be answered:
Why to irrigate?
What is irrigation scheduling?
What are the different prospective of Irrigation scheduling?
What are the different management approaches?
What are the components of Scheduling Irrigation Water?
Why to irrigate?
Prior to learning how can irrigation water be managed effectively, the
importance of water to the plant and how a plant uses water must be
understood. Irrigation is not done to retain the soil wet. Irrigation will not be
practiced just because the neighbors irrigate or because our ancestors
irrigate. It will be done for one target, which is to fulfill the needs of a crop of
economic or aesthetic value.
The objective of the irrigation process is to store the applied water by human
in the soil reservoir to be used in succeeding days when the plant needs it.
However, not all the applied water is stored in accessible spot which enables
the plant to recover it in the succeeding days. It can be imagined that the
soil water reservoir is a tank with certain capacities and levels that differ
from one soil type to another.
7.4.2 Determination of irrigation scheduling
Irrigation scheduling is a tool to efficiently apply water to improve the
performance of the irrigation system. Irrigation scheduling may be assorted
depending on different views. Regarding time frame, irrigation scheduling
may be done for a long term or short term. Long term scheduling is usually
done in the design stage or in the resource allocation stage, before the
beginning of the season. Short term scheduling deals with the daily decision
of operation or in other-wards, the immediate stage Long term scheduling,
may also be used to make an irrigation time table in arid area. As the
rainfall may be neglected and the long term weather condition nearly
uniform, from year to year, regarding the frequency of irrigation, irrigation
scheduling may be dynamic or static. A dynamic irrigation scheduling tries
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to modify the scheduling process to improve the system performance
according to the expected or unexpected constraints to finally satisfy the
required objective.
In static scheduling, each field and irrigation is viewed independently and
no change in the predetermined schedule is usually made. Regarding the
concept of scheduling, it may be traditional, reactive or predictive. The
traditional method, based on
a known rotation of field in sequence,
availability of water or
by practice.
Reactive scheduling, depends on some indicators which explain that
irrigation water is needed. These indicators may be
the crop appearance,
or soil water status.
The crop appearance as an indicator is inferior for modern agricultural,
because of its low accuracy. The crop yield may be affected as the plant may
suffer from water stress before the appearance of any visual indicators. It
also does not determine the amount of needed water. The soil water status
as an indicator may be either the soil water content or the soil water
depletion. Both of them can be measured directly or estimated and transfer
direct feedback from the soil. Using water content as an indicator enables
the irrigator to know how much water to apply.
This indicator is also not applicable in long term scheduling or short
dynamic where the forecasted profile of the water stress is needed Predictive
method of irrigation scheduling predicts the crop water use in the near
future to foresee the water need and schedule irrigation before water stress
affects the crop growth. The predictive method depends on the root zone
water balance equations (Jensen, et al., 1971; Heermann, 1980; Harrington
and Heermann, 1981).The method of irrigation,
surface, drip or sprinkle
and the nature of cultivation; single crop, multi-crop or multi-field, dictates
the irrigation scheduling strategy. For example, for multi- field operation,
the irrigation scheduling gives a range of irrigation dates for each field. The
earliest data recommended, is when the calculated depletion reaches the
applied net irrigation depth. The latest date is the day that the soil water
content reaches the predetermined water content, that will not affect the
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crop yield. The range of dates allows the farmer to arrange other farming
requirements.
Hence a dynamic short term predictive scheduling is the suitable strategy.
Irrigation scheduling may also have different concepts and definitions
according to an individual’s perspective of an irrigation system. For the
operator of an irrigation water delivery system, irrigation scheduling is,
when he has to supply water for how long and what rate for each delivery
point of the distribution system. For the individual irrigator, irrigation
scheduling is, predicting when he starts the next irrigation and what is the
suitable irrigation depth Irrigation scheduling is also defined as utilizing
the calculated crop water requirements to manage different fields under a
single entity.
What is the target?
The target is to manage all the fields to achieve an overall management
objective. the management objective may be
– maximizing production,
– maximizing profits,
– Minimizing energy cost, minimizing labor, or many other things.
Institutions, where energy cost represents a major cost of providing water,
minimizing energy will be the main objective of the management. Maximizing
profits sometimes will not be the main target, since minimizing the risk may
be required for financial reasons.
Load Management
One of the problems facing power suppliers in irrigating areas, is the high
peak electrical demand. These short term peaks require generation and
transmission facilities that will not be fully used during much of the year.
Thus the cost of supplying power will increase. Some power suppliers
imposed penalties on the peak annual demand. Other power suppliers ask
for voluntary shut-offs of electrical irrigation pumps during periods of
expected peak power usage. With the increase of the load, it is difficult to
determine the peak load reduction magnitude.
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Water Management
Since the scheduling of many fields requires repetitious calculations and
detailed accounting, it is favorable to being computerized. Irrigation
scheduling with the use of computers was initiated with the development of
the USDA irrigation scheduling program (Jensen et al., 1971). This program
uses climatic data as input to predict the crop water use and maintain soil-
water budget.
Integrated Load and Water Management
Water management through irrigation scheduling alone will tend to cause
peak electrical demands when the irrigation responds to peak demands of
crop water use. On the other hand, load management that is controlled by
the power supplier will tend to increase total pumping as the irrigator will
tend to apply more water than required to be safe if power is shut off.
Irrigation scheduling has been integrated with electric load management to
reduce energy cost and water conservation without decreasing the crop yield
significantly.
Fertilizer Management
As a result of managing both water and energy, an additional benefit may be
achieved. This benefit is fertilizer saving. Looking to the soil as a tank, once
it is full, any additional water will go out as a deep percolation. Some
fertilizers, like nitrogen, are easily dissolved in water and tends to go with
the water.
7.5 Principles of scheduling irrigation water
Irrigation scheduling is a process of determining
1. when to irrigate ?
2. how much water is required to meet the specified irrigation
objectives?
The amount replaces the water lost from the crop in the form of
evapotranspiration (ET) less the effective precipitation. The amount of losses
is mainly dependent on the energy produced by the atmosphere. Any crop
takes its needs of water from the soil in the root zone. The soil data
necessary for irrigation scheduling and how to obtain them as well as into
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the soil-water-plant relationship. The soil acts as a reservoir of water in the
soil. This reservoir is filled through irrigation and rainfall and emptied by
the plant (transpiration), evaporation from the soil surface and deep
percolation beyond the root zone. Each soil type has its own storage capacity
determined by its texture. The storage capacity is relatively small in sandy
soils as compared to that for clays.
Soil water content can be maintained in a favorable range. Therefore, it is
the soil water reservoir that is managed rather than crop stress in most
cases. To effectively manage soil water content and answer the second
question which is when to irrigate? Some soil parameters must be
discussed. The higher level of the tank represents the saturation capacity
(SC) the water content of the soil if the applied water fills all the voids in the
soil and there is almost no air. At this level, the soil particles cannot hold all
that amount of water, some water will exit from the tank by gravity.
This amount of water that exit from the tank represents the deep
percolation.
After some time according to the soil type, most of the gravity water will be
removed from the soil reservoir and at this point the existing water level
represents the field capacity (FC). When plants use water in different
activities, mainly in transpiration to avoid over-heating, the level of the
water in the tank will decrease till it reaches a low level. The plant roots
cannot use it or in other words the plants cannot overcome the gravitational
forces between the soil particles and the surrounding water. This water
stress results in a permanent injury or death of the plant, so it is called
permanent wilting point (PWP).
The maximum useful capacity of the tank is the difference between the field
capacity and the permanent wilting point; This represents the water holding
capacity (WHC) of the soil reservoir. When water content is below a certain
level, a crop will show some degree of water stress that will adversely affect
the crop growth and the yield. This water content is termed as critical or
optimum water content.
It is usually used in a different way in practice, which is the fraction of the
available water that can be depleted without damaging the crop. It is usually
called management allowable depletion (MAD). The management allowable
depletion is a function of the degree of maturity of the crop and the crop
type itself. All these levels are usually expressed as depth of water per depth
of soil in field practice.
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When to start irrigation?
In traditional irrigation process, when water is available, irrigation starts
when the soil reaches the critical level, and ends when it raises the soil
water back to the field capacity within the root zone. The capacity of the
tank is not constant during the growing season, as it begins with a small
capacity after planting and increases with time till the plant reach the
effective cover. This means that the rooting depth (RD) of the plant differs
according to the stage of growth of the plant. Knowing the rooting depth will
help to determine the amount of water to be applied without causing deep
percolation losses.
When water is applied rapidly even by a poorly designed sprinkler system or
poorly managed furrow irrigation or vigorous rains, the infiltration rate will
be less than the application rate and that water may be redistributed or
even leave the field as run off.
As a result of that, the applied water or the so called gross irrigation depth
(Idg) is usually greater than necessary. The percentage of water which is
beneficially used by crop to the applied water is usually called application
efficiency (EA).
Before starting irrigation, the current soil water content (SWC) is supposed
to be estimated. Then the actual amount of water that will be required to
raise the water content to the field capacity will be calculated. Irrigation
frequency is defined as the frequency of applying water to a particular crop
at a certain stage of growth and is expressed in days. In equation form it
reads:
Depth of irrigation (d), including application losses, applied to the soil in one
irrigation application and which is needed to bring the soil water content of
root zone to field capacity; mm. The depth of irrigation application (d)
including application losses is:
Ea
DSapd
*)*(
Where :
d = depth of irrigation application (mm)
p = fraction of available soil
Sa = total available soil water (mm/m) :soil depth
D = Rooting depth (m)
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Ea = application efficiency, fraction
Since P,D and Etcrop will vary over growing season, the depth in mm and
interval of irrigation in days will vary.
Irrigation Interval (i)
Irrigation frequency is defined as the frequency of applying water to a
particular crop at a certain stage of growth and is expressed in days. In
equation form it reads:
Irrigation interval (days) (i) =ETc
RZDPSa
Where:
(i) = Irrigation interval (days)
Sa = Total available soil moisture = (FC – PWP) (mm/m)
P = Allowable depletion (decimal)
RZD = Effective root zone depth (m)
ETc = Crop evapotranspiration or crop water requirement (CWR) (mm/day)
Estimation of soil water contents
Estimation of soil water contents may be done using soil based
measurements like direct gravitational method, tension meters, resisting
blocks, neutron probes and remote sensing. A limitation of these methods is
that the soil water content cannot be correctly forecasted in the near future.
Probably, the most effective and convenient methods for managing irrigation
today, is to estimate the water requirements using soil water accounting.
Deep percolation and surface runoff are usually small compared to
evapotranspiration in the pressurized irrigation systems. Moreover, by
keeping soil water content below field capacity, runoff and deep percolation
could be minimized. Groundwater contribution can be computed from
Darcy law, but in general it is negligible unless a high groundwater table is
existing. Effective rainfall can be estimated by a simple infiltration formula,
but it is generally small compared to evapotranspiration in arid and semi-
arid areas. Hence, evapotranspiration (ET) is the most important component
in estimating the crop water requirements.
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7.6 Irrigation efficiencies
Not all water taken from source to be used for irrigation, reaches its
destination by plants. Part of the water is lost during transport through the
canals and the fields. The remaining part is stored in the root zone and use
by plants. In other words, only part of the water is used efficiently, the rest
of the water is lost. These lost occurs:
1. Evapotranspiration from the water surface
2. Deep percolation to soil layers underneath the canals
3. Seepage through bund of the canals
4. Overtopping the bunds
5. Bund breaks
6. Run off in the drain
7. Rat holes in the canal bunds.
The losses mentioned above are shown on the following figure.
Different loses of water in the scheme
To express which percentage of the irrigation water is used efficiently and
which percentage is lost, the term irrigation efficiency is used. The scheme
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irrigation efficiency (e in %) is the part of the water pumped or diverted
through the scheme inlet which is used efficiently by the plants. The scheme
irrigation efficiency divided in
A) The conveyance efficiency (ec)
which represents the efficiency of water transport in canals and;
• The conveyance efficiency mainly depend on:
• The length of the canals
• The soil type or permeability of the canal banks
• The condition of the canals.
B) The field application efficiency (ea)
Application efficiency (ea) represents the efficiency of water application in
the field. In large irrigation scheme more water is lost than in small
schemes, due to a longer canal system. From canals in sandy soils more
water is lost than from canals in heavy clay soils. Deep percolation and
surface runoff are usually small compared to evapotranspiration in the
pressurized irrigation systems. Moreover, by keeping soil water content
below field capacity, runoff and deep percolation could be minimized.
Groundwater contribution can be computed from Darcy law, but in general
it is negligible unless a high groundwater table is existing. Effective rainfall
can be estimated by a simple infiltration formula, but it is generally small
compared to evapotranspiration in arid and semi-arid areas. Hence,
evapotranspiration (ET) is the most important component in estimating the
crop water requirements.
Crop water use = ETc = ETo×Kc
ETc: Crop evapotranspiration
ETo: Reference crop evapotranspiration in mm/day
Kc: Crop coefficient
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Crop Coefficient Curve Typical Shape of Crop Coefficient Curve
Stress coefficient
The water stress coefficient justifies the reduction in evapotranspiration.
This reduction happens, when the soil water depletion is increased and the
leaf cell becomes exposed to dehydration and damage. As a defense
mechanism, the stomata close to limit water loss and leaf temperature
begins to rise. A second mechanism is also used to reduce the amount of
heating by wilting of the leaves. If the depletion still increases, the plant may
reach to the permanent death.
It is necessary to assume a certain minimum rooting depth for germination
and emergence, before the development of the roots. This minimum rooting
depth is assumed to be constant till the development date and then
increases linearly till it reaches a maximum value at the effective cover date
and be constant after that date.
0
0 .1
0 .2
0 .3
0 .4
0 .5
0 .6
0 .7
0 .8
0 .9
1
0 0 .1 0 .2 0 .3 0 .4 0 .5 0 .6 0 .70 .8 0 .9 0 10 20 30 40 50 60 70 80 90 100
F rac t ion o f Tim e to F u ll C over D ay s A fte r F u ll C over
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Annex-1
Sensitivity of various field crops to water shortage
Sensitivity Low Low-Medium Medium-High High
Crops Cassava Alfalfa beans Banana
Cotton Citrus cabbage fresh green
Millet Grape maize vegetables
pigeon pea Groundnuts onion paddy rice
Sorghum Soybean peas Potato
Sugarbeet pepper sugarcane
Sunflower tomato
Wheat (water)melon
Source: FAO, Irrigation Water Management Training manual no. 4 Irrigation scheduling
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Annex-2
Periods sensitive to water shortage
Crop Sensitive period
Alfalfa just after cutting
Alfalfa (for seed prod.) Flowering
Banana Throughout
Bean flowering and pod filling
Cabbage head enlargement and ripening
Citrus flowering and fruit setting more than fruit enlargement
Cotton flowering and boll formation
Grape vegetative period and flowering more than fruit filling
Groundnut flowering and pod setting
Maize flowering and grain filling
Olive just prior to flowering and yield formation
Onion bulb enlargement
Onion (for seed prod.) Flowering
Pea/fresh flowering and yield formation
Pea/dry ripening
Pepper Throughout
Pineapple vegetative period
Potato stolonization and tuber initiation
Rice head development and flowering
Sorghum flowering and yield formation
Soybean flowering and yield formation
Sugarbeet first month after emergence
Sugarcane vegetative period (tillering and stem elongation)
Sunflower flowering more than yield formation
Tobacco period of rapid growth
Tomato flowering more than yield formation
Watermelon flowering and fruit filling
Wheat flowering more than yield formation
Source: FAO, Irrigation Water Management Training manual no. 4 Irrigation scheduling
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List of Authors
Name of Guidelines and Manuals Name Field Affiliation
Guideline for Irrigation Master Plan Study Preparation on Surface Water Resources
Mr. Nobuhiko Suzuki Water resources planning
Ministry of Agriculture, Forestry and Fisheries
Mr. Roba Muhyedin Irrigation Engineer OIDA Head Office
Manual for Runoff Analysis Mr. Yasukazu Kobayashi Runoff Analysis LANDTEC JAPAN, Inc.
Manual of GIS for ArcGIS (Basic & Advanced Section)
Mr. Ron Nagai GIS Application KOKUSAI KOGYO CO., LTD.
Manual on Land Use Classification Analysis Using Remote Sensing
Mr. Kazutoshi Masuda Remote Sensing KOKUSAI KOGYO CO., LTD.
Guidance for Oromia Irrigation Development Project Implementation
Mr. Kenjiro Futagami Facility Design/Construction Supervision
Ministry of Agriculture, Forestry and Fisheries
Study and Design Technical Guideline for Irrigation Projects (Irrigaiton Engineering Part)
Mr. Naoto Takano Facility Design/ Construction Supervision
Ministry of Agriculture, Forestry and Fisheries
(Socio-Economy, Community, Financial and Economic analysis Part)
Mr. Tafesse Andargie Economist OIDA Head Office
(Agronomy and Soil Part) Mr. Abdeta Nate'a Agronomist OIDA Head Office
Technical Guideline for Design of Headworks
Mr. Motohisa Wakatsuki Head works design Sanyu Consultants Inc.
Technical Guideline for Small Scale Reservoir
Mr. Haruo Hiki Project Management/ Planning/Reservoir
Sanyu Consultants Inc.
Technical Guideline for Irrigation Canal and Related Structures
Mr. Naoto Takano Facility Design/ Construction Supervision
Ministry of Agriculture, Forestry and Fisheries
Construction Control Manual Mr. Yoshiaki Otsubo Construction Supervision (Bura SSSIP)
Tokura Corporation
Guidance for Preparation of Operation and Maintenance Manual
Mr. Kenjiro Futagami Facility Design/Construction Supervision
Ministry of Agriculture, Forestry and Fisheries
Irrigation Water Users Association Formation and Development Manual
Mr. Tafesse Andargie Economist OIDA Head Office
Strengthening Irrigation Water Users Association (IWUA) Guideline
Mr. Yasushi Osato Strengthening of WUA
Nippon Koei Co.
Mr. Tafesse Andargie Economist OIDA Head Office
Small Scale Irrigation Water Management Guideline (Irrigation Water Supply Part)
Mr. Yohannes Geleta Irrigation Engineer OIDA Head Office
(Field Irrigation Water Management Part)
Mr. Abdeta Nate'a Agronomist OIDA Head Office
Remarks: Affiliation is shown when he work for CBID project.
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List of Experts who contributed to revise guidelines and manuals (1/5)
Office Name Specialty
OIDA Head office Mr. Abdeta Nate'a Agronomist
OIDA Head office Mr. Kibrom Driba Irrigation Engineer
OIDA Head office Mr. Kurabachew Shewawerk Agronomist
OIDA Head office Mr. Lemma Adane Irrigation Engineer
OIDA Head office Mr. Roba Muhyedin Irrigation Engineer
OIDA Head office Mr. Shemeles Tefera Agronomist
OIDA Head office Ms. Sintayehu Getahun Irrigation Engineer
OIDA Head office Mr. Tafesse Andargie Economist
OIDA Head office Mr. Tafesse Tsegaye Irrigation Engineer
OIDA Head office Mr. Tatek Worku Irrigation Engineer
OIDA Head office Mr. Teferi Dhaba Irrigation Engineer
OIDA Head office Mr. Terfasa Fite Irrigation Engineer
OIDA Head office Mr. Tesfaye Deribe Irrigation Engineer
OIDA Head office Mr. Yohannes Dessalegn Economist
OIDA Head office Mr. Yohannes Geleta Irrigation Engineer
OWMEB Mr. Girma Etana Irrigation Engineer
OWMEB Mr. Kedir Lole Irrigation Engineer
Arsi Mr .Dedefi Ediso Agronomist
Arsi Mr. Birhanu Mussie Irrigation Engineer
Arsi Mr. Dinberu Abera Sociologist
Arsi Mr. Hussen Beriso Economist
Arsi Mr. Mulat Teshome Surveyor
Arsi Mr. Segni Bilisa Agronomist
Arsi Mr. Shewngezew Legesse Irrigation Engineer
Japan International Cooperation Agency (JICA) & Oromia Irrigation Development Authority (OIDA) The Project for Capacity Building in Irrigation Development (CBID)
33
Small Scale Irrigation Water Management Guideline
List of Experts who contributed to revise guidelines and manuals (2/5)
Office Name Specialty
Arsi Mr. Tamerwold Elias Irrigation Engineer
Arsi Mr. Tesfaye Gudisa Irrigation engineer
Arsi Mr. Teshome Eda'e Irrigation Engineer
Arsi Ms. Worknesh Kine Geologist
Bale Mr. Abboma Terresa Irrigation Engineer
Bale Mr. Abdulreshed Namo Irrigation Engineer
Bale Mr. Beyan Ahmed Economist
Bale Mr. Diriba Beyene Irrigation Engineer
Bale Mr. Firew Demeke Teferi Irrigation engineer
Bale Mr. Gosa Taye Debela Irrigation engineer
Bale Mr. Zeleke Agonafir Agronomist
Borena Mr. Dida Sola Irrigation Engineer
East Harerge Mr. Abdi Abdulkedar Irrigation Engineer
East Harerge Mr. Elias Abdi Irrigation Engineer
East Harerge Mr. Shemsedin kelil Irrigation Engineer
East Harerge Ms. Eskedar Mulatu Economist
East Shewa Mr. Andaregie Senbeta Economist
East Shewa Mr. Bekele Gebre Irrigation Engineer
East Shewa Mr. Dilibi ShekAli Sociologist
East Shewa Mr. Ejara Tola Agronomist
East Shewa Mr. Girma Niguse Irrigation Engineer
East Shewa Mr. Kebebew Legesse Irrigation Engineer
East Shewa Mr. Mulatu Wubishet Agronomist
East Shewa Mr. Tadesse Mekuria Agronomist
Japan International Cooperation Agency (JICA) & Oromia Irrigation Development Authority (OIDA) The Project for Capacity Building in Irrigation Development (CBID)
34
Small Scale Irrigation Water Management Guideline
List of Experts who contributed to revise guidelines and manuals (3/5)
Office Name Specialty
East Shewa Ms. Tigist Amare Irrigation Engineer
East Shewa Mr. Zerfu Seifu Irrigation Engineer
East Welega Mr. Benti Abose Economist
East Welega Mr. Birhanu Yadete Agronomist
East Welega Mr. Dasalegn Tesema Economist
East Welega Mr. Gamachis Asefa Irrigation Engineer
East Welega Mr. Getachew Irena Agronomist
East Welega Mr. Kidane Fekadu Irrigation Engineer
East Welega Mr. Milikesa Workeneh Irrigation Engineer
East Welega Ms. Mulunesh Bekele Irrigation Engineer
East Welega Mr. Samson Abdu Irrigation Engineer
East Welega Mr. Tulam Admasu Irrigation Engineer
East Welega Ms. Yeshimebet Bule Economist
Guji Mr. Abadir Sultan Sociology
Guji Mr. Dawud Menza Irrigation Engineer
Guji Mr. Fikadu Mekonin Geologist
Guji Mr. Megersa Ensermu Irrigation Engineer
Guji Mr. Wandesen Bakale Economist
Horoguduru Welega Mr. Seleshi Terfe Economist
Horoguduru Welega Mr. Temesgen Mekonnen Irrigation Engineer
Horoguduru Welega Mr. Tesfaye Chimdessa Economist
Illubabor Mr. Ahmed Sani Irrigation Engineer
Jimma Mr. Lebeta Adera Irrigation Engineer
Kelem Welega Mr. Ayana Fikadu Agronomist
Japan International Cooperation Agency (JICA) & Oromia Irrigation Development Authority (OIDA) The Project for Capacity Building in Irrigation Development (CBID)
35
Small Scale Irrigation Water Management Guideline
List of Experts who contributed to revise guidelines and manuals (4/5)
Office Name Specialty
Kelem Welega Mr. Megarsa Kumara Hydrologist
Kelem Welega Mr. Oda Teshome Economist
Northe Shewa Mr. Henok Girma Irrigation Engineer
South West Shewa Mr. Bedasa Tadele Irrigation Engineer
South West Shewa Mr. Gemechu Getachew Irrigation Engineer
West Arsi Mr. Abebe Gela Irrigation Engineer
West Arsi Mr. Demissie Gnorie Irrigation Engineer
West Arsi Mr. Feyisa Guye Irrigation Engineer
West Arsi Mr. Hashim Hussen Economist
West Arsi Mr. Jemal Jeldo Economist
West Arsi Mr. Mekonnen Merga Environmentalist
West Arsi Mr. Mohamedsafi Edris Irrigation Engineer
West Arsi Mr. Molla Lemesa Agronomist
West Arsi Mr. Tamene Kena Sociologist
West Arsi Mr. Tibaho Gobena Irrigation Engineer
West Harerge Mr. Alemayehu Daniel Agronomist
West Harerge Mr. Dereje Kefyalew Irrigation Engineer
West Harerge Mr. Ferid Hussen Irrigation Engineer
West Harerge Mr. Nuredin Adem Irrigation Engineer
West Harerge Mr. Seifu Gizaw Economist
West Shewa Mr. Jergna Dorsisa Irrigation Engineer
West Shewa Mr. Solomon Mengistu Agronomist
West Shewa Mr. Zerhun Abiyu Irrigation Engineer
West Welega Mr. Belaye kebede Irrigation Engineer
Japan International Cooperation Agency (JICA) & Oromia Irrigation Development Authority (OIDA) The Project for Capacity Building in Irrigation Development (CBID)
36
Small Scale Irrigation Water Management Guideline
List of Experts who contributed to revise guidelines and manuals (5/5)
Office Name Specialty
West Welega Mr. Busa Degefe Economist
West Welega Mr. Temesgen Runda Irrigation Engineer
Ministry of Agriculture Mr. Amerga Kearsie Irrigation Engineer
Ministry of Agriculture Mr. Zegeye Kassahun Agronomist
Amhara Agriculture Bureau
Mr. Assefa Zeleke Economist
OWWDSE Mr. Damtew Adefris Irrigation Engineer
OWWDSE Mr. Demelash Mulu Irrigation Engineer
OWWDSE Mr. Teshoma Wondemu Irrigation Engineer
Latinsa SC. Mr. Aschalew Deme Irrigation Engineer
Latinsa SC. Mr. Daba Feyisa Agronomist
Metaferia Consulting Engineers
Mr. Getu Getoraw Irrigation Engineer
Metaferia Consulting Engineers
Mr. Hassen Bahru Sociologist
Metaferia Consulting Engineers
Ms. Nitsuh Seifu Irrigation Engineer
Remarks: Office Name is shown when he/she works for CBID project.
Japan International Cooperation Agency (JICA) & Oromia Irrigation Development Authority (OIDA) The Project for Capacity Building in Irrigation Development (CBID)
37
Small Scale Irrigation Water Management Guideline
List of Editors
Name of Guidelines and Manuals Name Field Affiliation
Guideline for Irrigation Master Plan Study Preparation on Surface Water Resources
Mr. Ermias Alemu Demissie Irrigation Engineer Lecturer in Arba Minch University
Mr. Zerihun Anbesa Hydrologist Lecturer in Arba Minch University
Technical Guideline for Design of Headworks
Technical Guideline for Irrigation Canal and Related Structures
Mr. Ermias Alemu Demissie Irrigation Engineer Lecturer in Arba Minch University
Mr. Bereket Bezabih Hydraulic Engineer (Geo technical)
Lecturer in Arba Minch University
Construction Control Manual Mr. Eiji Takemori Construction Supervision (Hirna SSIP)
LANDTEC JAPAN, Inc.
Construction Control Manual Dr. Hiroaki Okada
Construction Supervision (Sokido/Saraweba SSIP)
Sanyu Consultants Inc.
Construction Control Manual Mr. Shinsuke Kubo Construction Supervision (Shaya SSIP)
Independent Consulting Engineer
Technical Guideline for Design of Headworks
Construction Control Manual Mr. Toru Ikeuchi
Chief Advisor/Irrigation Technology
JIID (The Japanese Institute of Irrigation and Drainage)
Technical Guideline for Design of Headworks
Construction Control Manual Mr. Kenjiro Futagami
Facility Design/Construction Supervision
Ministry of Agriculture, Forestry and Fisheries
All Guidelines and Manuals Mr. Hiromu Uno Chief Advisor/Irrigation Technology
Ministry of Agriculture, Forestry and Fisheries
Manual for Runoff Analysis Manual of GIS for ArcGIS
(Basic & Advanced Section) Manual on Land Use
Classification Analysis Using Remote Sensing
Mr. Nobuhiko Suzuki Water resources planning
Ministry of Agriculture, Forestry and Fisheries
Guidance for Oromia Irrigation Development Project Implementation
Study and Design Technical Guideline for Irrigation Projects
Technical Guideline for Design of Headworks
Technical Guideline for Small Scale Reservoir
Construction Control Manual Guidance for Preparation of
Operation and Maintenance Manual
Irrigation Water Users Association Formation and Development Manual
Strengthening Irrigation Water Users Association (IWUA) Guideline
Small Scale Irrigation Water Management Guideline
Mr. Naoto Takano Facility Design/ Construction Supervision
Ministry of Agriculture, Forestry and Fisheries
Remarks: Affiliation is shown when he work for CBID project.
Japan International Cooperation Agency (JICA) & Oromia Irrigation Development Authority (OIDA) The Project for Capacity Building in Irrigation Development (CBID)
38
Small Scale Irrigation Water Management Guideline
List of Coordinators
Name Field Affiliation
Mr. Ryosuke Ito Coordinator/Training Independent
Mr. Tadashi Kikuchi Coordinator/Training Regional Planning International Co.
Remarks: Affiliation is shown when he work for CBID project.
Japan International Cooperation Agency (JICA) & Oromia Irrigation Development Authority (OIDA) The Project for Capacity Building in Irrigation Development (CBID)
39
Small Scale Irrigation Water Management Guideline
Contact Person
Mr. Yohannes Geleta (Irrigation Engineer; Environmentalist)
(Tel: 0911-981665, E-mail: [email protected]) Mr. Tafesse Andargie (Economist)
(Tel: 0911-718671, E-mail:[email protected]) Mr. Abdeta Nate'a (Agronomist)
(Tel: 0912-230407, E-mail: [email protected])
Oromia Irrigation Development Authority (OIDA) Tel: 011-1262245 C/O JICA Ethiopia Office Mina Building, 6th & 7th Floor, P.O.Box 5384, Addis Ababa, Ethiopia Tel : (251)-11-5504755 Fax: (251)-11-5504465