Water is vital for realizing full potential of agriculture sector and countrys development. The productivity in fields is severely affected by the vagaries of the 8C8son. Droughts, alternating With floods have been a common feature, making irrigation and modern agricultural technology indispensable. A good system of irrigation removes uncertainty about agricultural production by reducing the dependence on rains and assuring regular, continuous and copious water supply at the appropriate time for the crops. It helps in having multiple crops in a year from the field, ensuring full employment for the workers throughout the year. Assured supply of water helps adoption of modem agricultural technology, which in turn helps in increa8in~ productivity. Irrigation helps in more economical use of land by bringing in more area, including wastelands under cultivation. The importance of irrigation has been realized in the planning process and a large outlay has been provided for the sector. With sustained and systematic development of irrigation. Its potential has increased from 22.6 mha prior to 1951 to about 95.4 mha at the end of 2000. Against this, the utilization of irrigation potential at the end of 2000 was about 85.4 mha. Irrigation projects with a Culturable Command Area (CCA) of more than 10, 000 hectare are cla8sified as major projects and these with a CCA of more than 2, 000 hectare and upto 10, 000 hectare a8 medium projects. The irrigation system is based on three sub-systems, viz.
Tapping adequate resources of water
Preservation and conveyance of the water made available
Optimum utilization of the water resources called the water management systems.
Types of Irrigation
Three main types of irrigation are known:
Well Irrigation: Open wells, dug wells, dug cum bored wells and tube welle provide an assured supply of water. Tubewells are very popular in north India as power operated tube-wells can provide water for a longer period of time and cater to a large area.
Tank Irrigation: Tanks provide good storage of rain water for use in the dry season. They are found in different sizes In south India.
Canal Irrigation: Canals, carrying water from major rivers, transfer water to the deficient areas. They form the former means of irrigation in India accounting for about 40% of the irrigated land. Perennial canals have an assured supply of water throughout the year. While Inundated canals get water only during the rainy season. Storage canals get water from the reservoirs, conatructed specifically to store rain water.
Command Area Development Programme
It was initiated in 1974 − 75 with the objective of bridging the gap between potential created and utilized for optimizing agricultural production from irrigated land. The main assumption behind the program is that the potential for improvement in the utilization of water is maximum and that the underperformance of irrigation systems is directly linked to the absence of any government. Involvement and influence over on-farm development activities like land shaping and leveling, construction of field channels and drains. Realignment of field boundaries wherever necessary, enforcement of a proper system of warabandi and fair d18tribution of water to individual fields and supply of all inputs and services including credit and strengthening of extension services. The program Selection and introduction of suitable cropping pattern; Development of ground water to supplement surface irrigation; Development and maintenance of the main and intermediate drainage system and modernization, maintenance and efficient operation of the irrigation system. Beginning with 60 major and medium irrigation projects in 1974, the Program included 236 irrigation projects at the end of 2002 with Culturable Command Area (eCA) of 22.78 million hectare spread over 28 states and two union territories. The performance of CAD program has been found to be generally disappointing. Farmers disputes over land consolidations, absence of cooperation among various government departments and the lack of an integrated approach to the problem of soil and water management are the main resources of CADs poor performances. To make CAD a success, farmers active involvement and cooperation in development activities is very essential.
Dryland Rainfed Farming
Dryland or Rainfed agriculture is practiced on about 73 per cent of the net cultivated area but its contribution accounts for only about 42 per cent of the total food grains production. Coarse grains, pulses, cotton and oilseeds are produced in the rainfed areas. The main constituents of dry farming techniques are soil management, harvesting of water, new crop varieties and new agronomic practices. Soil management includes measures relating to soil structure, soil fertility and correction of alkalinity of the soil. Development of modern water harvesting procedures including the use of Aluminium foil, polymer films and widespread installation of small water reservoirs. The new agronomic practices envisage the proper application of nutrients.