Contents preface (VII) introduction 1—37

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• Table 1.8 Statewise navigable length of inland waters in India (6)
• Total 10241 4303
• Total 10075 2498
• NEED OF IRRIGATION IN INDIA
• Table 1.10 Frequency of droughts in India (7)
• Frequency 6 3 6 3
• Table 1.11 Periodicity of droughts in different regions (8)
• DEVELOPMENT OF IRRIGATION IN INDIA
• 1.6. MAJOR AND MEDIUM IRRIGATION SCHEMES OF INDIA
• Table 1.12 State-wise ultimate irrigation potential and potential created and utilised
• (Unit: Thousand Hectares)
• Table 1.13 Old irrigation systems needing modernisation (8)
• 1.8. COMMAND AREA DEVELOPMENT

Grand Total	84044					12175.38				6021.22					21.65

Total estimated navigable length of inland waterways of the country is 14544 km (see Table 1.8) of which maximum navigable length (2441 km) lies in Uttar Pradesh and Uttaranchal followed by West Bengal with 2337 km. Table 1.9 shows navigable lengths of important river systems of the country.

Table 1.8 Statewise navigable length of inland waters in India (6)

Sl. No.	State		Navigable Waterways (km)
		Rivers		Canals		Total
1.	Andhra Pradesh	309		1690		1999
2.	Assam	1983		–		1983
3.	Bihar and Jharkhand	937		325		1262
4.	Goa, Daman & Diu	317		25		342
5.	Gujarat	286		–		286
6.	Jammu & Kashmir	200		–		200
7.	Karnataka	284		160		444
8.	Kerala	840		708		1548
9.	Maharashtra	501		–		501
10.	Orissa	761		224		985
11.	Tamil Nadu	–		216		216
12.	U.P. and Uttaranchal	2268		173		2441
13.	West Bengal	1555		782		2337
	Total__10241_____4303'>Total	10241		4303		14544

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Table 1.9 Navigable length (in km) of important river systems in India (6)

Sl. No.	River System	Navigable Length
		By Boats	By Steamers
1.	Ganga	3355	853
2.	Brahmaputra	1020	747
3.	Rivers of West Bengal	961	784
4.	Rivers of Orissa	438	42
5.	Godavari	3999	–
6.	Krishna	101	–
7.	Narmada	177	48
8.	Tapti	24	24
	Total	10075	2498

Inland water transport is the cheapest mode of transport for bulk cargo. In view of this, the following ten waterways have been identified for consideration to be declared as National Waterways (6):

(i) The Ganga-Bhagirathi-Hoogli (ii) The Brahmaputra
(iii) The Mandavi Zuari river and the Cumbarjua canal in Goa. (iv) The Mahanadi

(v) The Godavari

(vi) The Narmada
(vii) The Sunderbans area (viii) The Krishna

(ix) The Tapti

(x) The West Coast canal

4. 
   NEED OF IRRIGATION IN INDIA
   

The rainfall in India is very erratic in its spatial as well as temporal variations. The average annual rainfall for India has been estimated at 1,143 mm which varies from 11,489 mm around Cherrapunji in Assam (with the maximum one-day rainfall equal to 1040 mm) to 217 mm around Jaisalmer in Rajasthan. Besides, 75% to 90% of the annual rainfall occurs during 25 to 60 rainy days of the four monsoon months from June to September (2). In addition, there is also a large variation from year to year, the coefficient of variation being more than 20% for most parts of the country (2).

Erratic behaviour of the south-west monsoon is the main cause of India’s frequent droughts (Table 1.10) and floods. The recent proposal (Appendix–1) of the Government of India on interlinking of some major rivers of the country is aimed at (i) increasing the utilizable component of the country’s water resources, and (ii) solving the problems of shortages and excesses of water in some parts of the country. Table 1.11 shows the values of the approximate probability of deficient rainfall (deficiency equal to or greater than 25 per cent of the normal) for different regions (8). Dependability of rainfall is thus rather low from the agriculture point of view and storage is essential to sustain crops during non-monsoon periods and also to provide

10 IRRIGATION AND WATER RESOURCES ENGINEERING
water for irrigation during years of low rainfall. For a large part of any crop season, the evapotranspiration (i.e., the water need of a crop) exceeds the available precipitation and irrigation is necessary to increase food and fibre production. About 45 per cent of agricultural production in India is still dependent on natural precipitation. The need and importance of irrigation in India can be appreciated from the mere fact that the country would need to produce 277 million tonnes (against the production of about 185 million tonnes for 1994-95) of food to meet the per capita requirement of 225 kg (i.e., about one-fourth of a tonne) per year for an estimated population of 1,231 million in the year 2030 (8).

Frequency_of_droughts_in_India_(7)'>Table 1.10 Frequency of droughts in India (7)

Quarter	1801–25	1826–50	1851–75	1876–1900	1901–25	1926–50	1951–75	1976–2000
Century
Drought	01,04,06	32,33	53,60,62	77,91	01,04,05	39,41	51,65,66	79,82
Years	12,19,25	37	66,68,73	99	07,11,13		68,72,74	85,87
					15,18,20
					25
Frequency	6	3	6	3	10	2	6	4
of drougts

Table 1.11 Periodicity of droughts in different regions (8)

Region	Recurrence of the period
	of deficient rainfall
Assam	Very rare, once in 15 years
West Bengal, Madhya Pradesh, Konkan,
Coastal Andhra Pradesh, Maharashtra,
Kerala, Bihar, Orissa	Once in 5 years
South interior Karnataka, eastern Uttar Pradesh,
Vidarbha	Once in 4 years
Gujarat, eastern Rajasthan, western Uttar Pradesh,
Tamil Nadu, Kashmir, Rayalaseema, Telengana	Once in 4 years
Western Rajasthan	Once in 2½ years

In addition, the export of agricultural products earns a major part of foreign exchange. Because of vastly different climate in different parts of the country, a variety of crops are produced in India. The country exports basmati rice, cotton, fruits (mango, apple, grapes, banana etc.), vegetables (potato, tomato etc.), flowers (rose etc.), and processed food products in order to earn precious foreign exchange. Still further, about seventy per cent of the country’s population is employed in agricultural sector and their well-being, therefore, primarily depends on irrigation facilities in the country.

5. 
   DEVELOPMENT OF IRRIGATION IN INDIA
   

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irrigation has received much attention since the beginning of civilization. The Grand Anicut across the river Cauvery was built in the second century. At the beginning of the 19th century, there were a large number of water tanks in peninsular India and several inundation canals in northern India. The Upper Ganga canal, the Upper Bari Doab canal and the Krishna and Godavari delta systems were constructed between 1836 and 1866. The famines of 1876–78, 1897–98 and 1899–1900 led to the setting up of the first Irrigation Commission in 1901 to ascertain the usefulness of irrigation as a means of protection against famine and to assess the extent of irrigation development required and the scope for further irrigation work. At this time (1901) the total gross irrigated area was only 13.3 Mha which increased to 22.6 Mha in 1950 as a result of a spurt in protective irrigation schemes (8).

The Bengal famine of 1943 underlined the urgency of increasing agricultural production to meet the needs of the growing population. After independence, the country began an era of planned development starting with the first five-year plan in 1951. The Planning Commission assigned a very high priority to irrigation development for increasing agricultural production. Giant projects like the Bhakra-Nangal, Hirakud, Damodar Valley, Nagarjunasagar, Rajasthan canal, etc. were taken up. This resulted in a great spurt in irrigation development activities and the irrigated area increased from 22.6 Mha in 1950–51 to 68 Mha in 1986–87. In June 1993, the irrigated area was 83.48 Mha i.e., 2.39 Mha more than that in June 1992. The year-wise development of irrigation potential in India since 1950–51 and up to 1994–95 is shown plotted in Fig. 1.1. The present food grain production is slightly more than 200 million tonnes.

	100
										85	87.8
	80								83
								76.5					grainproduction(Milliontonnes)
Irrigationpotential(M.Ha)							67.5
	60
						56.6
											250
	40				44.1						200
				37.1					179.5	182		190
							171
									150
		29
										145.5					Food
	20		22.6		94	104.6			109.7				100
			82
		50.8										50
	0	1950-51	60-61	68-69		80-81		89-90			0
		73-74	84-85	92-93	93-94	94-95
							Year
Fig. 1.1 Development of irrigation potential and production of food grains in India

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The total ultimate irrigation potential is estimated (6) at 115.54 Mha (see Table 1.12 for statewise distribution) of which 58.47 Mha would be from major and medium irrigation schemes and the remaining from minor irrigation schemes (6).
1.6. MAJOR AND MEDIUM IRRIGATION SCHEMES OF INDIA
Major irrigation schemes are those which have culturable command area (C.C.A.)* more than 10,000 ha. Irrigation schemes having C.C.A. between 2,000 and 10,000 ha are classed as medium irrigation schemes (8). The important schemes of the first two plan periods include Bhakra-Nangal, Rajasthan canal, Gandhi Sagar dam, Gandak, Kosi, Nagarjunasagar, Hirakud, Tungabhadra, Malaprabha, and Ghatprabha projects. Later, the multipurpose Beas project, Ramganga dam and canals, Sri Ramsagar, Jayakwadi, Ukai, Kadana, Sardar Sarovar, Tawa, Teesta, etc. were taken up for utilising the monsoon waters.
The performance of major and medium irrigation schemes was examined by the National Irrigation Commission (1972), the National Commission on Agriculture (1976), and several other committees. It was found that the available irrigation potential was not fully utilised. The difference between the available and utilised irrigation potential exceeds 4.0 Mha. Waterlogging and salinity damaged large areas. Moreover, the return in terms of increased agricultural production was far below the expectations. For all these deficiencies, the following causes were identified (8).
(i) Need for modernisation of the pre-Plan and early-Plan systems to provide water at the outlet delivery points to farmers at the right time and in the right quantity.
(ii) Lack of adequate drainage resulting in waterlogging conditions due to excess water used in irrigating crops as well as due to soil characteristics.
(iii) The absence of a distribution system within the outlet and the non-introduction of rotational distribution of water to the farmers.
(iv) Inadequate attention to land consolidation, levelling and all other aspects which can promote a better on-farm management of water.
(v) Lack of anticipatory research on optimum water use, particularly in black soils with considerable moisture retention capacity.
(vi) Lack of suitable infrastructure and extension services.
(vii) Poor coordination between the concerned Government organisations in the command areas.
Irrigation projects constructed prior to 1965 were designed to meet the irrigation demand of traditional crops. With the use of high-yielding varieties of seeds since 1965, many of the earlier projects became inadequate to meet the exacting demands for water in respect of high-yielding varieties of crops.
Modernisation of the old irrigation systems listed in Table 1.13 has, therefore, become necessary (8). The weaknesses in the old structures, adequate capacity of the canals to cope with the latest cropping patterns, deficiencies in the control structure system, causes of heavy
* Gross command area of an irrigation system is the total area which can be economically irrigated from the system without considering the limitations of the quantity of available water. Area of the cultivable land in the gross command of an irrigation system is called the culturable command area (C.C.A.). For more details, see Sec. 5.2.

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upto 1992–93 (6)		Potential Utilised		Minor			2670.42	59.04	472.40	4488.24	16.95	1815.75	1491.92	124.04	354.51	1416.59	500.50	2408.02	2236.10	42.24	39.14	9.33	56.41	1129.68	3266.38	2349.88	17.62	2121.37	84.05	18304.00	2345.90	78.14	47898.62
			Major and	Medium		2849.59	–	114.31	2300.00	12.00	1057.76	1803.00	4.20	140.10	1208.99	379.26	1434.50	1036.00	53.15	–	–	–	1349.05	2323.70	1899.62	–	1544.97	2.00	5828.00	1268.65	7.13	26615.98
Table 1.12 State-wise ultimate irrigation potential and potential created and utilised
		Potential Created		Minor			2887.94	68.09	583.05	5078.90	18.89	1921.27	1534.77	144.05	366.42	1546.56	536.13	2601.19	2489.40	51.22	45.08	11.04	65.90	1276.50	3320.00	2425.62	22.84	2118.97	91.88	19850.00	2832.37	82.41	51880.49
(Unit: Thousand Hectares)			Major and	Medium		3005.35	–	181.55	2770.00	13.00	1275.18	2047.00	8.21	172.10	1421.04	428.89	2032.00	2076.39	61.80	–	–	–	1426.56	2381.70	2043.36	–	1545.00	2.00	6860.00	1362.08	15.13	31128.34
	Total	Irrigation	Potential		9500	150	2670	12400	82	4847	4550	335	800	4600	2100	11200	7300	240	120	70	90	6100	6550	5350	72	4200	215	25700	6110	188	115539
	Minor Irrigation		Ground	Water		2200	e	700	4000	e	1500	1500	50	150	1200	300	3000	2000	5	15	e	5	1500	3500	2000	2	1500	15	12000	2500	49	39691
			Surface	Water		2300	150	1000	1900	25	347	50	235	400	900	800	2200	1200	100	85	70	75	1000	50	600	50	1200	100	1200	1300	41	17378
			Major and	Medium	Surface	Water	5000	e	970	6500	57	3000	3000	50	250	2500	1000	6000	4100	135	20	e	10	3600	3000	2750	20	1500	100	12500	2310	98	58470
			State					Andhra Pradesh	Arunachal Pradesh	Assam	Bihar and Jharkhand	Goa	Gujarat	Haryana	Himachal Pradesh	Jammu & Kashmir	Karnataka	Kerala	M.P. andChattishgarh	Maharashtra	Manipur	Meghalaya	Mizoram	Nagaland	Orissa	Punjab	Rajasthan	Sikkim	Tamil Nadu	Tripura	U.P and Uttaranchal	West Bengal	Union Territories		Total
			Sl. No.					1.	2.	3.	4.	5.	6.	7.	8.	9.	10.	11.	12.	13.	14.	15.	16.	17.	18.	19.	20.	21.	22.	23.	24.	25.	26.

e: included under Union Territories.

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losses in the irrigation channels, methods to augment canal supplies in tail reaches, and other aspects of modernisation are being looked into for some important projects.
Table 1.13 Old irrigation systems needing modernisation (8)

Sl. No.	Name of Canal System	Year of	Area irrigated
		Construction	(105 hectares)
1.	Godavari Delta (Andhra Pradesh)	1890	5.58
2.	Krishna Delta (Andhra Pradesh)	1898	4.42
3.	Sone Canal (Bihar)	1879	3.47
4.	Tribeni Canal (Bihar)	1914	0.48
5.	Western Yamuna Canal (Haryana)	1892	4.81
6.	Ranbir Canal (Jammu and Kashmir)	1904	0.54
7.	Tandula Reservoir (Madhya Pradesh)	1921	0.67
8.	Mahanadi Canal (Madhya Pradesh)	1927	0.85
9.	Nira Left Bank Canal (Maharashtra)	1906	0.48
10.	Godavari Canal (Darna Dam and	1916	0.32
	Nander Weir) (Maharashtra)
11.	Nira Right Bank Canal (Maharashtra)	1938	0.35
12.	Krishna Raj Sagar Dam and Canals	1930	0.51
	(Karnataka)
13.	Mahanadi Canals (Orissa)	1895	1.12
14.	Upper Bari Doab Canal System (Punjab)	1879	3.35
15.	Sirhind Canal (Punjab)	1887	6.00
16.	Ganga Canal (Rajasthan)	1928	3.03
17.	Cauvery Delta System (Tamil Nadu)	1889	4.29
18.	Periyar System (Tamil Nadu)	1897	0.62
19.	Upper Ganga Canal (Uttar Pradesh)	1854	6.99
20.	Lower Ganga Canal (Uttar Pradesh)	1878	5.28
21.	Agra Canal (Uttar Pradesh)	1873	1.38
22.	Sarda Canal (Uttar Pradesh)	1926	6.12
23.	Eastern Yamuna Canal (Uttar Pradesh)	1854	1.91
24.	Midnapur Canal (West Bengal)	1889	0.50
25.	Damodar Canal (West Bengal)	1935	0.73

The drainage problem is acute in the states of Punjab and Haryana. It also prevails in the command areas of some of the irrigation projects of UP, West Bengal, Gujarat, Madhya Pradesh, and Maharashtra. Serious waterlogging and consequent salinity problems have arisen in the Chambal Project areas in Madhya Pradesh and Rajasthan, the Kosi and Gandak Project areas in Bihar, Tungabhadra in Karnataka, Nagarjunasagar in Andhra Pradesh, and the Kakrapar system in Gujarat. Inadequate drainage and consequent waterlogging prevails in the Purna, Pravara, and Neera projects in Maharashtra, Dantiwara in Gujarat, Barna and Tawa in Madhya Pradesh, Lower Ganga canal in UP, Malampuzha in Kerala, Periyar-Vaigai in Tamil Nadu, Tungabhadra in Andhra Pradesh and Karnataka, the Sone system in Bihar,

INTRODUCTION

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Ranbir and Pratap canals in Jammu and Kashmir, Hirakud and Mahanadi Delta in Orissa, and Krishna Delta in Andhra Pradesh. According to the estimates of the National Commission on Agriculture (1976), a total area of about 6 Mha is waterlogged (8).

1.7. MINOR IRRIGATION
Minor irrigation schemes include all ground water and surface water irrigation (flow as well as lift) projects having culturable command area up to 2000 ha. Minor surface water flow irrigation projects include storage and diversion works and are the only means of irrigation in several drought-prone tracts such as undulating areas south of the Vindhyas and also hilly regions. Such projects offer considerable opportunity for rural employment and also help in recharging the meagre resources of ground water in the hard rock areas. When available surface water cannot be used for irrigation through construction of flow irrigation schemes due to topographical limitations, surface water lift irrigation schemes provide the solution.
Ground water is widely distributed and provides an instant and assured source of irrigation to farmers. It improves the status of irrigation supply and helps in controlling waterlogging and salinisation in the command area of a canal. Ground water development is the major activity of the minor irrigation programme. It is mainly a cultivator’s own programme implemented primarily through individual and cooperative efforts. Finance for such programmes are arranged through institutional sources. The first large-scale venture in scientific planning and development of ground water was initiated in India in 1934 when a project for the construction of about 1,500 tubewells in the Indo-Gangetic plains in the Meerut region of Uttar Pradesh was undertaken. Adequate energy for pumping ground water is essential for near-normal production of crops when there is severe drought. Hence, energy management is also essential. Besides electricity and diesel, biogas-operated pumps need to be popularised. The use of solar energy through photovoltaic systems will, probably, be the ultimate solution to the energy problem. Wind energy should also be tapped in desert, coastal and hilly regions.

1.8. COMMAND AREA DEVELOPMENT
The irrigation potential created by the construction of a large number of major and medium irrigation projects has more than doubled since independence. However, the available irrigation potential has always been under-utilized and the optimum benefits by way of increased production have not been fully realised. Several studies have been made to analyse the reasons for inefficient and continued under-utilisation of available irrigation potential and unsatisfactory increase in agricultural production in irrigated areas. The Second Irrigation Commission and the National Commission on Agriculture recommended an integrated command area development programme for optimising benefits from available irrigation potential. The objectives of the programme were as follows (9):
(i) Increasing the area of irrigated land by proper land development and water man-agement.
(ii) Optimising yields by adopting the best cropping pattern consistent with the avail-ability of water, soil, and other local conditions.
(iii) Bringing water to the farmer’s field rather than only to the outlets and thus assuring equitable distribution of water and adequate supply to tailenders.
(iv) Avoiding wastage and misuse of water.
(v) Optimising the use of scarce land and water resources, including ground water where available, in conjunction with necessary inputs and infrastructure.

16 IRRIGATION AND WATER RESOURCES ENGINEERING
The command area development programme is a series of coordinated measures for optimising the benefits from the irrigated agriculture. Some of these measures are (8):
(i) Scientific crop planning suited to local soil and climatic conditions. (ii) Consolidation of holdings and levelling/shaping of lands.

(iii) Provision of field channels to ensure equitable distribution of water to the farmer’s field.

(iv) Ensuring the supply of other inputs (good quality seeds, fertilisers, etc.).
(v) Construction of rural roads, markets, storages, and other infrastructural facilities in the command areas of irrigation projects.
The Second Irrigation Commission (10) stressed the need for a programme of integrated command area development involving cooperative efforts among the State Departments of Irrigation, Agriculture, Animal Husbandry, Community Development, Finance and Public Works and other institutions like Agriculture Refinance Corporation, Land Development Banks, Commercial Banks, etc. The commission suggested the formation of a special administrative agency for the coordinated and expeditious development of command areas under major and medium irrigation projects. The functions of such agencies would be to assign tasks to various departments and institutional organisations to enforce coordination among them and to ensure the implementation of the agreed programme. As a result, in 1973, State Governments were requested to set up Command Area Development Authorities for 50 irrigation projects in the country.
In December 1974, the formation of a Central Sector Scheme for Command Area Development Programme in selected irrigated commands was approved by the Government of India. This programme included the following components (8) :
(i) Modernisation and efficient operation of the irrigation system.
(ii) Development of a main drainage system beyond the farmer’s blocks of 40 ha. (iii) Construction of field channels and field drains.

(iv) Land shaping/levelling and consolidation of holdings. (v) Lining of field channels/watercourses.

(vi) Exploitation of ground water and installation of tubewells. (vii) Adoption and enforcement of a suitable cropping pattern. (viii) Enforcement of an appropriate rostering system on irrigation.
(ix) Preparation of a plan for the supply of key inputs like credit, seeds, fertilisers, pesti-cides, and implements.
(x) Making arrangements for timely and adequate supply of various inputs.
(xi) Strengthening of existing extension, training, and demonstration organisations.
The National Commission on Agriculture emphasised the need for development of land in the command area in an integrated manner comprising the following actions (8):
(i) Layout of plots and of common facilities like watercourses, field channels, drains and farm roads.
(ii) Consolidation of farmers’ scattered plots into one or two operational holdings. (iii) Construction of watercourses and field channels.

(iv) Construction of field drains where necessary and linking them with connecting drains.

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(v) Provision of farm roads.

(vi) Land formation to suitable slopes.
(vii) Introduction of the ‘warabandi’ system for rotational distribution of water.
For future irrigation projects, the National Commission on Agriculture suggested that the project report should be prepared in the following three parts (8):

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