water resources final

7/29/2019 Water Resources Final

1/47

1

Abstract

Water is one of the basic resources needed to sustain plant and animal life and

ultimately human existence. Judicious use of this resource should be the concern of all

people. This booklet gives a brief amount of estimated water resources and its efficient

use. This booklet describes the hydrologic cycle, types, utilization and economic use of

water. This will enable the farmer to use the water more scientifically and economically.


2/47

2

Introduction

Water is an essential requirement of all living beings and indispensable for many

human related activities. In nature it transports eroded material from mountains and

forests to the plains and the sea. Man uses water to carry away his wastes, generate

electric power, for navigation, industrial purposes and also as a source of recreation.

Apart from all these, the role of water in agriculture is very significant Water is a limited

resource and its efficient use is crucial to the survival of the human beings. Therefore,

every effort must be made to make the best use of water so as to make possible a high

level of continuous production. Several factors are to be kept in mind for the conservation

and development of water resources. These are as follows:

1. availability and source of water;

2. climatic condition;

3. quality of water;

4. factors affecting water resources;

5. distribution and variation of rainfall & water resources;

6. competing demands; and

7. nature of the soil. .


3/47

3

Water resources of a country constitute one of its vital assets. India receives annual

precipitation of about 4000 km3. The rainfall in India shows very high spatial and

temporal variability and paradox of the situation is that Mousinram near Cherrapunji,

which receives the highest rainfall in the world, also suffers from a shortage of water

during the non-rainy season, almost every year. The total average annual flow per year for

the Indian rivers is estimated as 1953 km3. The total annual replenish able groundwater

resources are assessed as 432 km3. The annual utilizable surface water and groundwater

resources of India are estimated as 690 km3 and 396 km3 per year, respectively. With

rapid growing population and improving living standards the pressure on our water

resources is increasing and per capita availability of water resources is reducing day by

day. Due to spatial and temporal variability in precipitation the country faces the problem

of flood and drought syndrome. Overexploitation of groundwater is leading to reduction

of low flows in the rivers, declining of the groundwater resources, and salt water intrusion

in aquifers of the coastal areas. Over canal-irrigation in some of the command areas has

resulted in water logging and salinity. The quality of surface and groundwater resources is

also deteriorating because of increasing pollutant loads from

Point and non-point sources. The climate change is expected to affect precipitation and

water availability. So far, the data collection, processing, storage and dissemination

have not received adequate attention. The efforts initiated under the Hydrology Project

Phase-I and the development of the Decision Support System proposed under Hydrology

Project Phase-II are expected to bridge some of the gaps between the developed advanced

technologies of water resources planning, designing and management and their field

applications. The paper presents availability and demands of water resources in India as

well as describes the various issues and strategies for developing a holistic approach for

sustainable development and management of the water resources of the country. It also


4/47

4

highlights integration of the blue and green flows and concepts of virtual water transfer

for sustainable management of the water resources for meeting the demands of the

present, without compromising the needs of future generations.


5/47

5

The overall navigable span of the inland watercourses in India is 14,500 km. The legal

authority in control of the watercourses in the country is the Inland Waterways Authority

of India or IWAI.

The national watercourses in India can be divided into three and they are as follows:

The Brahmaputra river system - extending from Sadiya to Dhubri

The Ganga Bhagirathi Hooghly river - extending from Allahabad in Uttar Pradesh to

Haldia in West Bengal

The West Coast Canal from Kottapuram to Kollam together with Udyogmandal canal and

Champakara canal.

The water bodies are top tourist draws as well. Visitors from different corners of the

world come to see these water resources. As a result, the travel and tourism sector of

India is getting a boost. In addition, a large number of hotels and accommodations have

come up around these visitor attractions to fulfill the requirements of the travelers. The

country houses 13 major ports and approximately 180 small and medium harbors. The

harbors manage over 95% of the commerce in the country and they also function as the

principal entranceways for doing business. The important ports in India are as follows:

Haldia, Kolkata, Visakhapatanam, Paradip, Chennai, Ennore, Cochin, Tuticorin,

Mormugao, New Mangalore, Mumbai, Jawaharlal Nehru Port Trust, and Kandla.

Rivers in India

The country houses 12 rivers that are categorized as important rivers. The overall

drainage basin watered by these rivers is more than 976,000 sq miles or 2,528,000 km2.

All the important rivers in the country have their sources in any of the following areas:


6/47

6

Vindhya and Satpura mountain range, forming a part of the heart of the country

The Karakoram and Himalayan mountain ranges

Sahyadri or Western Ghats mountain range, forming a part of western India

The biggest drainage basin in the country is created by the Ganges-Brahmaputra-

Meghana river network and it covers a total area of approximately 620,000 sq miles or

1,600,000 km2. The drainage basin of the Ganges river singularly covers a total area of

around 420,000 sq miles or 1,100,000 km2.

The source of the Ganges river is the Gangotri Glacier, which lies in the state of

Uttarakhand. Subsequently, the river runs in the southeast direction, before pouring into

the Bay of Bengal. The headwaters of the Gomti and Yamuna rivers lie in the western

part of the Himalayan mountain range. These two rivers meet the Ganga in the flat

terrain.

The Brahmaputra River has its headwaters in the territory of Tibet. In the province of

Tibet, people call it "Tsangpo" or Yarlung Tsangpo River. The river then penetrates the

Indian Territory via the state of Arunachal Pradesh in the Northeast. Subsequently, the

river moves to the west into Assam. In Bangladesh, the river meets the holy Ganga and

the name of the river changes to the Jamuna River.

A major branch of the river Ganga (Yamuna) is the Chambal River. The river has its

headwaters in the Satpura and Vindhya mountain ranges. It runs to the east. From the

same source, other rivers that have originated include the Tapti and Narmada and both of


7/47

7

these rivers pour into the Arabian Sea in the west. The river system that runs from the east

to west forms 10% of the overall outpouring of water in India.

All the rivers of the Deccan plateau have their headwaters in the Western Ghats mountain

range. These rivers include the Godavari River, the Mahanadi River (passing across the

delta formed by itself), Kaveri River, and Krishna River. All these rivers ultimately pour

into the Bay of Bengal. Approximately 20% of the overall outpouring of the country is

represented by these rivers.

The intense precipitation in the rainy season in the southwest results in the swelling of the

banks of the Brahmaputra and other rivers in India. This frequently leads to inundating of

the bordering regions. Despite the fact that these rivers work as a fundamentally reliable

source of fertilization and natural supply for the paddy cultivators, these inundations have

resulted in loss of lives of a large number of people and force the population of the area to

move to other places.

Capes in India

The major capes in India are as follows - Indira Point, the southernmost tip in India which

is situated on the Great Nicobar Island, the Kanyakumari, the southern point of territory

of India., Point Calimere, and Adam's (Rama's) Bridge.

Gulfs in India

The important gulfs in India are the Gulf of Kutch, the Gulf of Cambay, and the Gulf of

Mannar. The country houses straits like the Ten Degree Canal, which dissevers the

Andamans from the Nicobar Islands, the Palk Strait, which splits India from Sri Lanka,

and the Eight Degree Canal, dissevering the Lakshadweep and Amindivi Islands from the

Minicoy Island in the south.


8/47

8

The Indian Ocean and the Bay of Bengal are situated towards the south and east of the

country and the Arabian Sea is located in the west. The Andaman Sea and the

Lakshadweep Sea are smaller water bodies. The country houses four coral reefs and they

lie in the Gulf of Mannar, the Andaman and Nicobar Islands, the Gulf of Kutch, and the

Lakshadweep Islands.

Lakes in India

The major lakes in India are as follows - Vembanad Lake (Kerala), Sambhar Lake, (the

biggest saltwater lagoon of the nation in Rajasthan), Loktak Lake (Manipur), Kolleru

Lake (Andhra Pradesh), Chilka Lake (Orissa), Dal Lake (Kashmir), and Sasthamkotta

Lake (Kerala).

Water bodies that border India

Given below are the names of the water bodies that surround India from different sides:

Lakshadweep Sea in the southwest

Arabian Sea in the west

Bay of Bengal in the east

Indian Ocean in the south


9/47

9

Problem Statement, hypothesis and rationale

Total water in the world is estimated to be 1.5 billion cu km. About 95% of this is the

salty water found in the oceans. This comes to around 1.425 billion cu km. Remaining 5%

is fresh water i.e. only 75 million cu km. Out of this 75 million cu km 60 million cu km

are immobilized as continuously frozen polar ice and snow, leaving only 15 million cu

km as fresh liquid water for human, animal and plant needs. The world reserve of water

resources is given in Fig. 1.

World Water Resources

Of the 15 million cu km of fresh water about 1 % (150,000 cu kin) is surface

water found in rivers, lakes and streams and 99% is stored underground at varying depths.

About half of this ground water (7,000,000 cu km) is stored at depths greater than 1000

metres and is considered too expensive to pump to the surface for most uses. So total

usable water in the world is 7 million cu km of fresh ground water at reasonable depth

plus the 1,50,000 cu km of surface water.


10/47

10

III. Hydrologic Cycle

Consumable water is obtained through precipitation. Precipitation occurs by the

unending moisture cycle of the earth called hydrologic cycle. Moisture is constantly

circulating between the land, the ocean and the atmosphere. This hydrologic cycle has

neither a beginning nor an end. Radiation from the sun evaporates water from ocean,

lakes, rivers into the atmosphere. Transpiration also takes place from the vegetation and

adds water to the atmosphere. The water vapour rises and collects to form clouds. Under

certain conditions, the cloud moisture condenses and falls back to the earth as rain, hail,

sleet or snow. The whole process is diagrammatically given in two Figures 2a & 2b. The

Hydrologic Cycle.


11/47

11

Hydrologic cycle.


12/47

12

Hydrologic cycle.


13/47

13

Types of water resources

OF all the planets renewable resources, water has a unique place. It is essential for sustaining all

forms of life, food production, economic development, and for general well-being. It is

impossible to substitute for most of its uses, difficult to de-pollute, expensive to transport, and it is

truly a unique gift to mankind from nature. Water is also one of the most manageable of the

natural resources as it is capable of diversion, transport, storage, and recycling. All these

properties impart to water its great utility for human beings. The surface water and groundwater

resources of the country play a major role in agriculture, hydropower generation, livestock

production, industrial activities, forestry, fisheries, navigation, recreational activities, etc.

According to National Water Policy in the planning and operation of systems, water allocation

priorities should be broadly as: (i) drinking water, (ii) irrigation, (iii) hydropower, (iv) ecology,

(v) agro-industries and non-agricultural industries, and (vi) navigation. India receives annual

precipitation of about 4000 km3, including snowfall. Out of this, monsoon rainfall is of the order

of 3000 km3. Rainfall in India is dependent on the south-west and north-east monsoons, on

shallow cyclonic depressions and disturbances and on local storms. Most

of it takes place under the influence of south-west monsoon between June and September except

in Tamil Nadu, where it is under the influence of north-east monsoon

during October and November. India is gifted with a river system comprising more than 20 major

rivers with several tributaries. Many of these rivers are perennial and some

of these are seasonal. The rivers like Ganges, Brahmaputra and Indus originate from the

Himalayas and carry water throughout the year. The snow and ice melt of the Himalayas

and the base flow contribute the flows during the lean season. Lal2 mentioned that more than 50%

of water resources of India are located in various tributaries of these river systems. Average water

yield per unit area of the Himalayan rivers is almost double that of the south peninsular rivers

system, indicating the importance of snow and glacier melt contribution from the high mountains.


14/47

14

Apart from the water available in the various rivers of the country, the groundwater is also an

important source of water for drinking, irrigation, industrial uses, etc. It accounts

for about 80% of domestic water requirement and more than 45% of the total irrigation in the

country. As per the international norms, if per-capita water availability is less than 1700 m3 per

year then the country is categorized as water stressed and if it is less than 1000 m3 per capita per

year then the country is classified as water scarce. In India per

Capita surface water availability in the years 1991 and 2001 were 2309 and 1902 m3 and these

are projected to reduce to 1401 and 1191 m3 by the years 2025 and 2050 respectively. Hence,

there is a need for proper planning, development and management of the greatest assets of the

country, viz. water and land resources for raising the standards of living of the millions of people,

particularly in the rural areas.

Mans influence on hydrological cycle

The hydrological cycle is being modified quantitatively and qualitatively in most of the

river basins of our country as a result of the developmental activities such as construction

of dams and reservoirs, land use change, irrigation, etc.Such human activities affecting

the hydrological regime can be classified into four major groups: (i) activities which

affect river runoff by diverting water from rivers, lakes, and reservoirs or by groundwater

extraction, (ii) activities modifying the river channels, e.g. construction of reservoirs and

ponds, levees and river training, channel dredging, etc.(iii) activities due to which runoff

and other water balance components are modified due to impacts of basin surface e.g.

agricultural practices, drainage of swamps, forestation or deforestation, urbanization, etc.

and (iv) activities which may induce climate changes at regional or global scale,e.g.

modifying the composition of atmosphere by increasing the greenhouse gases or by

increased evaporation caused by large scale water projects. For understanding the effects

appropriately, hydrological modeling approaches have to be adopted3 .


15/47

15

Monsoon and its forecasting

The word monsoon is derived from mausim, Arabic word, which means season and the

word is applied to winds whose direction is reversed completely from one season to the

next season. The largest precipitation accumulations for periods greater than 24 h are

associated with the Asian monsoon. Normal duration of monsoon in India is about 100 to

120 days beginning from first June. In India, the two monsoon seasons (the southwest

monsoon in June to September and the northeast monsoon in November December)

bring forth rains. An important feature affecting the rainfall in India is the change in the

direction of wind currents that occurs in different months. In May when the weather is

very hot, the south-east trade winds from the south Indian Ocean cross the equator and

after deflecting, due to rotation of the earth, extend rapidly into the north Indian Ocean,

viz. the Bay of Bengal in early May and afterwards get established over both the sea

areas. This westerly current, which extends from the Arabic coast to the China Sea across

India, is known as the southwest monsoon. In winter season, the wind currents over India

Blow from north to south.

Precipitation variability

The long-term average annual rainfall for the country is 1160 mm, which is the highest

anywhere in the world for a country of comparable size2. The annual rainfall in India

however fluctuates widely. The highest rainfall in India of about 11,690 mm is recorded

at Mousinram near Cherrapunji in Meghalaya in the northeast5. In this region rainfall as

much as 1040 mm is recorded in a day. At the other extreme are places like Jaisalmer, in

the west, which receives barely 150 mm of rain. Though the average rainfall is adequate,


16/47

16

nearly three-quarters of the rain pours down in less than 120 days, from June to

September. As much as 21% of the area of the country receives less than 750 mm of rain

annually while 15% receives rainfall in excess of 1500 mm. Precipitation generally

exceeds 1000 mm in areas to the east of Longitude 78E. It reaches nearly to 2500 mm

along almost the entire west coast and over most of Assam and sub-Himalayan

West Bengal. Large areas of peninsular India receive rainfall less than 600 mm. Annual

rainfall of less than 500 mm is experienced in western Rajasthan and adjoining parts of

Gujarat, Haryana and Punjab. Rainfall is equally low in the interior of the Deccan lateau,

east of the Sahyadris. A third area of low precipitation is around Leh in Kashmir.


17/47

17

Figure 1. Distribution of normal annual rainfall in India (IMD, 2004).


18/47

18

Water resources of India

Although India occupies only 3.29 million km2 geographical areas, which forms 2.4% of

the worlds land area, it supports over 15% of the worlds population. The population of

India as on 1 March 2001 stood at 1,027,015,247 persons. Thus, India supports about

1/6th of world population, 1/50th of worlds land and 1/25th of worlds water resources7.

India also has a livestock population of 500 million, which is about 20% of the worlds

total livestock population. More than half of these are cattle, forming the backbone of

Indian agriculture. The total utilizable water resources of the country are assessed as 1086

km3. A brief description of surface and groundwater water resources of India is given

Below.

Surface water resources

In the past, several organizations and individuals have estimated water availability for the

nation. Recently, the National Commission for Integrated Water Resources

Development8 estimated the basin-wise average annual flow in Indian river systems as

1953 km3. The details are given in Table 1. Utilizable water resource is the quantum of

withdraw able water from its place of natural occurrence. Within the limitations of

physiographic conditions and socio-political environment, legal and constitutional

constraints and the technology of development available at present, utilizable quantity of

water from the surface flow has been assessed by various authorities differently. The

utilizable annual surface water of the country is 690 km3 (Table 1)9. There is

considerable scope for increasing the utilization of water in the GangaBrahmaputra

basins by construction of storages at suitable locations in neighboring countries.


19/47

19

Table 1. Basin wise average flow and utilizable water9 (in km3/year)


20/47

20

Groundwater resources

The annual potential natural groundwater recharge from0 rainfall in India is about 342.43

km3, which is 8.56% of total annual rainfall of the country. The annual potential

groundwater recharge augmentation from canal irrigation system is about 89.46 km3.

thus, total replenish able groundwater resource of the country is assessed as 431.89%.

After allotting 15% of this quantity for drinking, and 6 km3 for industrial purposes, the

remaining can be utilized for irrigation purposes. Thus, the available groundwater

resource for irrigation is 361 km3, of which utilizable quantity (90%) is 325 km3. The

estimates by the Central Groundwater Board (CGWB) of total replenish able groundwater

resource, provision for domestic, industrial and irrigation uses and utilizable groundwater

resources for future use are given in Table 2. The basin wise per capita ater

Availability varies between 13,393 m3 per annum for the BrahmaputraBarak basin to

about 300 m3 per annum for the Sabarmati basin. The state-wise estimates of dynamic

Groundwater (fresh) resource made by the CGWB10 is given in Table 3. The basin-wise

groundwater potential of the country is given in Table 4.

Water requirements of India.

Traditionally, India has been an agriculture-based economy. Hence, development of

irrigation to increase agricultural Production for making the country self-sustained and for

poverty alleviation has been of crucial importance for the planners. Accordingly, the

irrigation sector was assigned a very high priority in the 5-year plans. Giant schemes like

the Bhakra Nangal, Hirakud, Damodar Valley, Nagarjunasagar,Rajasthan Canal project,

etc. were taken up to increase irrigation potential and maximize agricultural production.


21/47

21

Long-term planning has to account for the growth of population. According to National

Water Policy1, the production of food grains has increased from around 50 million tones

in the fifties to about 203 million tones in the year 19992000. A number of individuals

and agencies have estimated the likely population of India by the year 2025 and 2050.

According to the estimates adopted by NCIWRD9, by the year 2025, the population is

expected to be 1333


22/47

22

million in high-growth scenario and 1286 million in low growth scenario. For the year

2050, high rate of population growth is likely to result in about 1581 million people

While the low growth projections place the number at nearly 1346 million. Keeping in

view the level of consumption, losses in storage and transport, seed requirement, and

buffer stock, the projected food-grain and feed demand for 2025 would be 320 million

tones (high-demand scenario) and 308 million tones (low-demand scenario). The

requirement of food grains for the year 2050 would be 494 million tones (high-demand

scenario) and 420 million tones (low demand scenario). Table 5 provides details of the

population of India and per capita water availability as well as utilizable surface water for

some of the years from 1951 to 2050 (projected). The availability of water in India shows

wide spatial and temporal variations. Also, there are very large inter annual variations.

Hence, the general situation of availability of per capita availability is much more

alarming than what is depicted by the average figures.


23/47

23

Domestic use

Community water supply is the most important requirement and it is about 5% of the total

water use. About 7 km3 of surface water and 18 km3 of groundwater are being used

for community water supply in urban and rural areas. Along with the increase in

population, another important change from the point of view of water supply is higher

rate of urbanization. According to the projections, the higher is the economic growth, the

higher would be urbanization. It is expected that nearly 61% of the population will be

living in urban areas by the year 2050 in high-growth scenario as against 48% in low

growth scenario. Different organizations and individuals have given different norms for

water supply in cities and rural areas. The figure adopted by the NCIWRD9 was 220 liter

per capita per day (lpcd) for class I cities. For the cities other than class I, the norms are

165 for the year 2025 and 220 lpcd for the year 2050. For rural areas, 70 lpcd and 150

lpcd have been recommended for the years 2025 and 2050. Based on these norms and

projection of population, it is estimated that by 2050, water requirements per year for

domestic use will be 90 km3 for low demand scenario and 111 km3 for high demand

scenario. It is expected that about 70% of urban water requirement and 30% of rural water

requirement will be met by surface water sources and the remaining from groundwater.


24/47

24

Irrigation

The irrigated area in the country was only 22.6 million hectare (Mha) in 195051. Since

the food production was much below the requirement of the country, due attention was

paid for expansion of irrigation. The ultimate irrigation potential of India has been

estimated as 140 Mha. Out of this, 76 Mha would come from surface water and 64 Mha

from groundwater sources. The quantum of water used for irrigation by the last century

was of the order of 300 km3 of surface water and 128 km3 of groundwater, total 428

km3. The estimates indicate that by the year 2025, the water requirement for irrigation

would be 561 km3 for low-demand scenario and 611 km3 for high-demand scenario.

These requirements are likely to further increase to 628 km3 for low-demand scenario

and 807 km3 for high-demand scenario by 2050.

Hydroelectric power

The hydropower potential of India has been estimated at 84,044 MW at 60% load factor.

At the time of independence, the installed capacity of hydropower projects was 508 MW.

By the end of 1998, the installed hydropower capacity was about 22,000 MW. The status

of hydropower development in major basins is highly uneven. According to an estimate,

India has plans to develop 60,000 MW additional hydropower by the twelfth five-year

plan. It includes 14,393 MW during the tenth five-year plan (20022007); 20,000 MW

during eleventh (20072012) and 26,000 MW during the twelfth (20122017) five-year

plans. A potential of the order of 10,000 MW is available for development of small

hydropower projects in the Himalayan and sub-Himalayan regions of the country.

Therefore, it is not only desirable but also a pressing need of time to draw a master plan

for development of small, medium and large hydro-schemes for power generation.

Industrial water requirement


25/47

25

Rough estimates indicate that the present water use in the industrial sector is of the order

of 15 km3. The water use by thermal and nuclear power plants with installed capacities of

40,000 MW and 1500 MW (1990 figures) respectively, is estimated to be about 19 km3.

In view of shortage of water, the industries are expected to switch over to water efficient

technologies. If the present rate of water use continues, the water requirement for

industries in 2050 would be 103 km3; this is likely to be nearly 81 km3 if water saving

technologies are adopted on a large scale.

Total water requirements

Total annual requirement of water for various sectors has been estimated and its break up

is given Table 6. With the increasing population as well as all round development in the

country, the utilization of water has also been increasing at a fast pace. In 1951, the actual

utilization of surface water was about 20% and 10% in the case of groundwater. The


26/47

26

utilizable water in river basins is highly uneven. For example in the Brahmaputra basin,

which contributes 629 billion m3 of surface water of the countrys total flow, only 24

billion m3 is utilizable.

Water resources management in India

In view of the existing status of water resources and increasing demands of water for

meeting the requirements of the rapidly growing population of the country as well as the

problems that are likely to arise in future, a holistic, well planned long-term strategy is

needed for sustainable water resources management in India. The water resources

management practices may be based on increasing the water supply and managing the

water demand under the stressed water availability conditions. Data monitoring,

processing, storage, retrieval and dissemination constitute the very important aspects of

the water resources management. These data may be utilized not only for management

but also for the planning and design of the water resources structures. In addition to these,

now days decision support systems are being developed for providing the necessary

inputs to the decision makers for water resources management. Also, knowledge sharing,

peoples participation, mass communication and capacity building are essential for

effective water resources management. Some important aspects of such strategies are

described as follows.

Flood management

Among all natural disasters, floods are the most frequent to be faced in India. Floods in

the eastern part of India, viz.Orissa, West Bengal, Bihar and Andhra Pradesh in the recent

past, are striking examples. According to the information published by different

government agencies, the tangible and intangible losses due to floods in India are

increasing at alarming rate. As reported by the Central Water Commission (CWC) under


27/47

27

the Ministry of Water Resources, Government of India, the annual average area affected

by floods is 7.563 Mha.

Drought management

The drought-prone area assessed in the country is of the order of 51.12 Mha. The

planning and management of the effects of drought appear to have a low priority due to

associated randomness and uncertainty in defining the start and end of droughts. Further,

most of the drought planning and management schemes are generally launched after

persisting drought conditions. The traditional system of drought monitoring and

estimating losses by crop cutting needs replacement with real time remote sensing, GIS,

GPS and modeling techniques for ensuring transparency and quick response. Scope of

losses may be extended to groundwater depletion, damage to perennial trees, plantations,

orchards and depletion in fertility of livestock.

Groundwater management

To protect the aquifers from overexploitation, an effective groundwater management

policy oriented towards promotion of efficiency, equity and sustainability is required.

Agricultural holdings in India are highly fragmented and the rural population density is

large. The exploitation of groundwater resources should be regulated so as not to exceed

the recharging possibilities, as well as to ensure social equity. The detrimental

environmental consequences of over-exploitation of groundwater need to be effectively

prevented by the Central and State Governments. Overexploitation of groundwater should

be avoided, especially near the coasts to prevent ingress of seawater into freshwater

aquifers1. Clearly, a joint management approach combining government administration

with active people participation is a promising solution.

Conjunctive use of surface and groundwater


28/47

28

Large canal infrastructure network for providing irrigation has been the prime goal of the

Government of India, since the first five-year plan, which continued up to seventh five-

year plan. In some of the irrigation project commands such as Sarda Sahayak in UP,

Gandak in Bihar, Chambal in Rajasthan, Nagarjuna Sagar in Andhra Pradesh,

Ghataprabha and Malaprabha in Karnataka etc., problems of water logging are being

faced. The main reason for excessive use of surface water as compared to groundwater is

its much lower price for irrigation as compared to the cost incurred in using

groundwater. Water logging problems could be overcome if conjunctive use of surface

and groundwater is made. Groundwater utilization for irrigation in waterlogged areas can

help to lower the groundwater table and reclaim the affected soil. Over exploitation of

groundwater in areas like Mehsana, in Gujarat; parts of Meeurt and Varanasi districts in

Uttar Pradesh, Coimbatore in Tamil Nadu and Karnal district in Haryana etc. have

resulted in mining of groundwater20. Many research workers have focused the causes of

waterlogging21. Several groundwater flow modeling studies have focused on assessing

the waterlogged areas and measures to control problems of water logging and

salinization22,23. It is desirable that the irrigation needs for fulfilling crop water

requirements should be satisfied by judicious utilization of available canal water in

conjunction with groundwater so as to keep the water table within the acceptable range.

Thus, the optimal conjunctive use of the regions surface and groundwater resources

would help in minimizing the problems of water logging and groundwater mining.

Water conservation

Water conservation implies improving the availability of water through augmentation by

means of storage of water in surface reservoirs, tanks, and soil and groundwater zone. It

emphasizes the need to modify the space and time availability of water to meet the

demands. This concept also highlights the need for judicious use of water. There is a great


29/47

29

potential for better conservation and management of water resources in its various uses.

On the demand side, a variety of economic, administrative and community-based

measures can help conserve water. Also, it is necessary to control the growth of

population since large population is putting massive stress on all natural resources. Since

agriculture accounts for about 69% of all water withdrawn, the greatest potential for

conservation lies in increasing irrigation efficiencies. Just a 10% improvement in

irrigation efficiency could conserve enough water to double the amount available for

drinking. In India, sprinkler irrigation is being adopted in Haryana, Rajasthan, Uttar

Pradesh, Karnataka, Gujarat and Maharashtra. The use of sprinkler irrigation saves about

56% of water for the winter crops of bajra and jowar, while for cotton, the saving is about

30% as compared to the traditional gravity irrigation. An important supplement to

conservation is to minimize the wastage of water. In urban water supply, for example,

almost 30% of the water is wasted due to leakages, carelessness, etc. while most metro

cities face deficit in supply of water. It is, therefore, imperative to prevent wastage. In

industries also, there is a scope for economy in the use of water.

Rainwater harvesting

Rainwater harvesting is the process to capture and store rainfall for its efficient utilization

and conservation to control its runoff, evaporation and seepage. Some of the benefits of

rainwater harvesting are:

It increases water availability

It checks the declining water table

It is environmentally friendly

It improves the quality of groundwater through dilution,


30/47

30

Mainly of fluoride, nitrate, and salinity, and

It prevents soil erosion and flooding, especially in the

Urban areas.

Even in ancient days, people were familiar with the methods of conservation of rainwater

and had practiced them with success. Different methods of rainwater harvesting were

developed to suit the geographical and meteorological conditions of the region in various

parts of the country. Traditional rainwater harvesting, which is still prevalent in rural

areas, is done by using surface storage bodies like lakes, ponds, irrigation tanks, temple

tanks, etc. For example,Kul (diversion channels) irrigation system which carries water

from glaciers to villages is practiced in the Spiti area of Himachal Pradesh. In the arid

regions of Rajasthan, rainwater harvesting structures locally known as Kund (a covered

underground tank), are constructed near the house or a village to tackle drinking water

problem. In Meghalaya, Bamboo Rainwater Harvesting for tapping of stream and spring

water through bamboo pipes to irrigate plantations is widely prevalent. The system is so

perfected that about 1820 liters of water entering the bamboo pipe system per minute is

transported over several hundred meters. There is a need to recharge aquifers and

conserve rainwater through water harvesting structures. In urban areas, rainwater will

have to be harvested using rooftops and open spaces. Harvesting rainwater not only

reduces the possibility of flooding, but also decreases the communitys dependence on

groundwater for domestic uses.


31/47

31

Recycle and reuse of water

Another way through which we can improve freshwater Availability is by recycle and

reuse of water. It is said that in the city of Frankfurt, Germany, every drop of water is

recycled eight times. Use of water of lesser quality, such as reclaimed wastewater, for

cooling and fire fighting is an attractive option for large and complex industries to reduce

their water costs, increase production and decrease the consumption of energy. This

conserves better quality waters for potable uses. Currently, recycling of water is not

practiced on a large scale in India and there is considerable scope and incentive to use this

alternative. Estimates25 show that recyclable water is between 103 and 177 km3/year for

low and high population projections.

People participation and capacity building for making the people of various sections of

the society aware about the different issues of water resources man SPECIAL

management, a participatory approach may be adopted. Mass communication

programmers may be launched using the modern communication means for educating the

people about water conservation and efficient utilization of water. Capacity building

should be perceived as the process whereby a community equips itself to become an

active and well-informed partner in decision making. The process of capacity building

must be aimed at both increasing access to water resources and changing the power

relationships between the stakeholders. Capacity building is not only limited to officials

and technicians but must also include the general awareness of the local population

regarding their responsibilities in sustainable management of the water resources. Policy

decisions in any water resources project should be directed to improve knowledge,

attitude and practices about the linkages between health and hygiene, provide higher

water supply service levels and to improve environment through safe disposal of human

waste. Sustainable management of water requires decentralized decisions by giving


32/47

32

authority, responsibility and financial support to communities to manage their natural

resources and thereby protect the environment.


33/47

33

Work Plan

On an average, India receives about 120 cm of precipitation in a year, mostly as

rainfall. .On volume basis this is 394.5 million hectare metre (m. ham). (let us take 400 m.

ha m as an approximate figure). The main source of precipitation is rainfall. India is a vast

country in the world compared to any other country having an annual rainfall of about

117 to 120 cm. Rainfall over the entire country during monsoon is nearly 75% of the

mean annual, while during pre-monsoon and post -monsoon seasons the country receives

almost the same amount of rainfall which is about 10 to 11 % of the mean annual. In

January and February the country receives just about 3.5% of the mean annual rainfall

and it is mostly confined to Jammu & Kashmir, Himachal Pradesh, Po.jab, North-West

U.P., North Bengal and Assam. Different monsoons is shown below in Tables 1 & 2

respectively.

Table 1 .Rainfall distribution In various states of India (in mm)

Sl.No. States Meteorological

Sub-divisions

Rainfall

1 Andhra Pradesh Costal

Telangana

Rayalaseema

935

891

893

2 North Eastern States Arunachal Pradesh

Assam

Nagaland

3736

2423

2065

3 Bihar Plateau

Plains

1490

1267


34/47

34

4 Gujarat Gujarat

Saurastra

1002

590

5 Haryana Haryana 772

6 Himachal Pradesh Himachal Pradesh 1971

7 Jammu & Kashmir Jammu & Kashmir 967

8 Karnataka Costal

North Interior

South Interior

3366

837

914

9 Kerala Kerala 2961

10 Madhya Pradesh West

East

1144

1470

11 Maharastra Madhya

Marathwada

Vidarbha

Konkan

706

780

1124

2871

12 Orissa Orissa 1486

13 Punjab Punjab 760

14 Rajasthan West

East

465

937

15 Tamil Nadu Tamil Nadu

Pondichery

1008

1335

16 Uttar Pradesh East

Plains

Hills

873

806

1840

17 West bengal Sub-Himalayan

Gangetic

3079

1846


35/47

35

Note: The above mentioned figures are based on the total rainfall received from

June to September during 1977-78.

On the basis of these, different regions of the country can be divided into three

categories viz., high rainfall areas, medium rainfall areas and low areas. The areas

receiving above 1,150 mm annual rainfall are high rainfall areas, those receiving between

750 and 1,150 mm are medium rainfall areas and the areas with annual rainfall below 750

mm are low rainfall areas.

Table 2 .Distribution and extent of rainfall through different monsoons

Sl.No. Time & type of monsoon % of rainfall

1. South West monsoon (June to Sept) 75

2. Post monsoon season ((Oct to Dec.) 1011

3. Winter season ( Jan to Feb) 3-4

4. Pre-monsoon season ( Mar to May) 10-11

.

IV. Types of Water Resources Based on Uses

According to the uses water resources may be classified into three main groups.

1. For consumptive uses

2. Partially consumptive uses

3. Non consumptive uses

1. Consumptive uses

Irrigation, urban and rural water supplies are grouped in this ' category, since, in these

situations, water is directly consumed by living beings.

2. Partially consumptive uses


36/47

36

Use of water for domestic and industrial purposes, thermal and nuclear power

generation, etc. are partially consumptive as, a part of the water can be renewed for reuse

after proper conditioning.

3. Non-consumptive uses

This includes the quantity required for hydro-power generation, navigation,

pollution control, recreation, preservation of fish and wild life etc.

V. Water Resources in India

According to the placement, water resources of India are : divisible into twodistinct categories:

A. Surface water resources

B. Ground water resources

The precipitation that falls on land is the ultimate source for both the categories of

water resources.

A. Surface water resources

When rain falls, a sizable portion is intercepted by the vegetation, or temporarilydetained in surface depressions. When the available interception or the depression

storages are completely exhausted and when the rainfall intensity at the soil surface

exceeds the infiltration capacity of the soils, the over land flow begins. This water reaches

the rivers, streams, lakes, surface reservoirs, darns, etc. Our irrigation mainly depends on

surface water resources. Runoff water from streams and rivers is stored in reservoirs or is

diverted directly through canal system for irrigation. Water resources region can be

planned on the basis of river basins.

1. River systems in India

Rivers are the main source of surface water. A river basin has well defined

watershed boundary and also has relationship with ground water resources in most of the

cases.

India has been divided into six river basins for the purpose of assessment of the

available water resources. The following table will present the location, climatological

factors, annual run-off and approximate volume of water of these six river basins. These

are:

a. Indus basin

b. Ganga system


37/47

37

c. Brahmaputra system

d. East coast

e. West coast and

f. Rajputana region

Table 3 -Different river basins of India

Sl.

No.

Important

River basin

State in the

region

Cath

Men

t

Area

(m

ha)

Avge

Annua

l

Precipi

Tation

M ha

metre

Total

Precipi

-

Tation

M ha

metre

Mean

Tempe-

Rature

OC

Avg

Annua

l

Runoff

M ha

metre

Volu

me

Of

Wate

r

M ha

metr

e

1 Ravi, Beas,

Sutlej

J &

Kashmir,

Punjab

Haryana

Himachal

prade

35.4

0

56.00 19.82 1260 07.94 04.93

2 Ganga,

Yamuna

Chambal

gogra

Guwduk,

Kosi

U.P. Bihar,

M.P

Rajasthan

& West

Bengal

97.6

0

111 108.3 16.80 48.96 18.50

3 Brahmaputra

,

Subausiri,

Manar

Teest

Assam,

Meghalaya

,

Nagaland

West

Bengal

50.6

2

122 61.72 08.20 38.08 1.23


38/47

38

4 Cavery,

Krishna,

Godavari,

Mahanadi,

Subarnarekha

Damodal

Madhya

Prades

Bihar,

Orissa,

West

Bengal

A.P.

Maharastra

Karnataka

Tamil

Nadu

121 109 131.9 26.1 41.19 33.80

5 Tapti,

Narmada,

Mahi,

Sabarmati

Gujarat,

Kerala

Maharastra

Karnataka

49.1

6

122 59.98 25.5 31.06 6.92

6 Luni &Ghagaoa

Rajasthan 16.80

29.00 04.87 26.2 - 1.22

7 Total 370.

61

--- 386.7 --- 167.2 66.6

The assessment of this surface reservoir is also calculated by lots of assumptions

on run-off, rainfall temperature etc. So this resource can be an approximate figure. All

these water resources cannot be utilized due to the limitations imposed by the

physiographic factors.

Surface water stored in reservoirs or diverted directly is distributed for irrigation

through the canal irrigation network. A canal starts either from a water storage dam or


39/47

39

diversion darn. Irrigation water flows through the complete canal system before it reaches

the farmer's field to be irrigated. The canal network consist- of canals, distributaries,

water courses and field channels.

B. Ground Water Resources

The main source of ground water is rainfall. However, ground water recharge is

supplemented by other sources such as seepage from canals and field channels, ponds,

tanks, effluent drainage from rivers, deep percolation from irrigated fields, etc. A part of

any of these water sources that infiltrates into surface soil may continue to move laterally

at a shallow depth. This water which flows below the soil surface may eventually reach

the stream channel. This flow of water below the surface is called sub surface run off. A

part of the sub surface run-off may enter the stream promptly, whereas the remaining part

may percolate deeply into the soil and remain above the water table in the zone of

saturated flow. This water table shows the upper level of ground water in the earth.

The total run-off in the stream channel includes the melted snow, the surface run-

off, the sub surface run-off and the ground water run -off. The portion of run-off water,

after infiltration reaches the ground water table, together with the contribution made to

ground water from a neighbouring basins, effluent rivers, natural lakes, ponds, artificial

storage reservoirs, and canals irrigations r constitutes the ground water resources.

This whole process is diagramatically explained below Figure 2

1. Ground water regions or India

The availability and development potential of ground water in India on the basis

of geological consideration can be described under the following three broad categories:

a. Unconsolidated rocks

b. Semi-consolidated rocks


40/47

40

Methodology

Utilization of Water Resources

Water resources are utilized mainly for three purposes:

1. Irrigation2. Industrial3. DomesticOut of these three, irrigation is the major consumer of water resources. The total

utilization of water in India is depicted in the following flow-chart in Figure 3. on the

Total Precipitation.

Total Precipitation

Our water resources are insufficient to meet the long term requirement of

agriculture, industry and other uses, unless its judicious and economic uses are ensured.


41/47

41

The total geographical area of our country is 328.7 million hectares (m.ha). About

42% of this area is under cultivation i.e., 140.7 m ha. Only 26.6% of this area is irrigated

through various sources. Following tables give the area irrigated by different sources

indifferent years and the States.

Table 6 .Irrigation potential or different sources or water

(Area in million hectars)

Sl.No. Sources 1981-82 1982-83 1983-84 1984-

85

1 Government canals 14.68

(36.3)

14.87

(37.2)

15.74

(37.5)

15.33

(36.5)

2 Private canals 0.84

(2.1)

0.495

(1.2)

0.495

(1.2)

0.495

(1.2)

3 Tanks 3.506

(8.8)

3.112

(7.8)

3.783

(9.0)

3.330

(8.0)

4 Tubewe/ls 9.900

(24.9)

10:684

(26.7)

10.973

(26.I)

11.265

(26.9)

5 Other wells 8.267

(20.8)

8.428

(21.1)

8.548

(20.4)

8.723

(20.9)

6 Other sources 2.566

(6.5)

2.375

(6.0)

2.411

(5.8)

2.600

(6.2)

7 Total irrigated area 39.764 39.969 41.995 41.779

(in bracket per cent of the area is shown)

Irrigation is mainly carried out through minor irrigation schemes as well as major

and medium irrigation schemes. Our nation has the potentiality to explore maximum

amount of water but technology and attempts have to be developed for the utilization.

Following table gives the potential created and utilized water.


42/47

42

Table 7. Net area irrigated by different sources (in thousand ha)

Sl

.No.

States Canals Tanks Tube

wells

Other

wells

Other

source

Total

Irrigat

ed area

1 Andhra Pradesh 1627 1100 114 470 126 3437

2 Assam 362 --- --- --- 210 572

3 Bihar 896 118 846 225 475 2760

4 Gujarat 245 25 130 999 15 1414

5 Haryana 1036 1 682 31 4 1754

6 Arunachal pradesh --- 0.5 2 1 87 90

7 Jammu & Kashir 280 0.5 2 1 11 302

8 Karnataka 480 410 0.5 336 131 1365

9 Kerala 86 58 54 NA 30 228

10 Madhya Pradesh 801 132 26 700 145 1804

11 Maharastra 379 260 -- 1046 117 1802

12 Manipur --- --- --- --- 65 65

13 Meghalaya --- --- --- --- 37 37

14 Orissa 655 233 NA 127 --- 1015

15 Punjab 1383 -- 1559 172 7 3121

16 Rajasthan 887 53 50 1219 30 2547

17 Tamil nadu 911 750 62 807 35 2565

18 Tripura --- 2 --- 0.5 23 30

19 Uttar pradesh 2473 330 3189 1314 349 7933

20 West Bengal 960 303 --- 17 209 1409

21 Union Territores 28 3 45 7 35 118


43/47

43

All India 13775 3986 6469 7557 2304 34491

NA = Not Available

Source: Water Use Efficiency in Agriculture by S. Giriappa, P.35.

Total ground water resources can irrigate 42.29 m ha, but present utilization is

only 10.01 m ha and remaining 32.28 m ha is left unutilized, though there is a potential to

explore it.

VII. Economic Use of Water Resources

Water is the most critical input in crop production. It also influences almost all the

bio-physiological processes of plants. When we speak of economic use of water, it refers

to the system which aims at optimum utilization of available water resources in crop

production without adversely affecting soil health. As we have discussed earlier the main

source of water for plant growth is irrigation, so while irrigating following important

points are to be kept in mind. These are:

--when to irrigate

--how much to irrigate

--how best to irrigate

Determination of water requirement and criteria for scheduling irrigation help to

define when to irrigate. The estimation of plant available moisture and deficit expressed

as depth in the rooting zone enables to decide how much to irrigate. Selection of suitable

method of irrigation in a given situation will meet the question how best to irrigate. Some

other measures for efficient management of irrigation water are discussed as below.


44/47

44

Solution of the problem

1. Check water logging

It is one of the major problems in water management. The concept of plant

available water capacity enables one to avoid application of excess water which further

helps to minimize waterlogging along with salinity and alkalinity. Frequent irrigations

maintain high soil moisture regime but it depends on the method adopted for irrigation.

2. Drainage

To avoid water logging condition and salt accumulation, the field should be

provided with a proper drainage system. The drainage provides suitable environment to

the development of plant root system and helps in optimizing crop production.

3. Disiltation of tanks

Siltation of tanks and reservoirs both traditional and modem, has added to the

gravity of problem of surface water management. It reduces the storage capacity of the

reservoir or tanks and increases in the volume and velocity of floods. Disiltation may be

difficult for the big reservoirs but this can be easily practised in tanks, ponds, ditches etc.

4. Ground water management

Management of surface water and ground water are equally important in water

harvesting and recycling. In areas that greatly depend on ground water for their irrigation

requirement, should be ensured that crops are provided with water during the critical

period of their growth. For this exploitation of ground water should be managed in a

balanced manner.


45/47

45

Total amount of precipitation received is constant, and its economical use is the

only way to increase production. At present, 29% of the total precipitation is lost through

surface run-off and 53% through infiltration. For better management of ground water, the

ultimate aim is to increase from 53% of the total precipitation moving into the soil to 100

per cent. This will recharge to ground water.

Ground water availability gets considerably reduced due to increased exploitation

and poor recharge conditions. Therefore, proper water balance between availability,

recharge and exploitation should be maintained. For this, a proper study and planning is

very necessary"

5. Watershed management

Watershed is the geographical area from which the entire surface run-off

originating due to the rainfall coverage flows through the existing drainage system

towards a common outlet Let us say, it is a small catchment area in which the excess

water of that particular region resulting from run-off is conserved either by check darns or

by gully plugs or through percolation ponds.

An important planning input is watershed management is to conduct the ground

water study. This study is undertaken to assess the ground water status, soil types and

water stored at various depths. With this information it will be possible to plan properly

the optimum utilization of the available water.


46/47

46

Conclusion

The above discussion underlines the fact that in the face of anticipated population

growth and technological advancement, the country's utilizable water resources are

limited and there is no ground for complacency in the matter. There is utmost need for

laying maximum emphasis on conservation and most efficient utilization of the available

water resources. Technological and management capabilities will have to be upgraded for

this purpose.


47/47

References

www.indiawaterportal.com

www.wbic.gov.in

www.cwc.gov.in

www.inseda.org
http://www.indiawaterportal.com/http://www.indiawaterportal.com/http://www.wbic.gov.in/http://www.wbic.gov.in/http://www.cwc.gov.in/http://www.cwc.gov.in/http://www.inseda.org/http://www.inseda.org/http://www.inseda.org/http://www.cwc.gov.in/http://www.wbic.gov.in/http://www.indiawaterportal.com/

water resources final

Documents