Irrigation is a vital input in the agricultural productivity and agricultural growth. More than 80% of available water resources worldwide as well as in India are being presently utilized for irrigation purposes. However, in India, the average water use efficiency of Irrigation Projects is assessed to be only of the order of 30-35%. There is no doubt that modernization of irrigation system like concrete lining to the inner surface of the open channel; canal automation etc. will save water significantly. But these techniques require huge capital investment, hence uneasy to adopt. On this background it is appropriate to know the innovative, simple, low cost, easy to adopt, water conveyance techniques used in the command of few irrigation projects in Maharashtra.
Ultimate irrigation potential of India is 140 million hectare. Irrigation potential to the tune of about 102 million hectare has been created through Major/Medium/minor surface water irrigation projects and use of ground water. However, potential utilisation is about 87 million hectare only Mahato (2013).Irrigation sector is the biggest consumer of water as more than 80% of available water resources in India are being presently utilized for irrigation purposes. However, the average water use efficiency of Irrigation Projects is assessed to be only of the order of 3035%. Mahato (2013). Presently the annual agricultural output is just sufficient to sustain our food grain requirement. To meet the challenge of regular expansion of size of population, the productivity of the water and land has to grow, as both the resources are limited. Water is a major and vital input to increase agricultural productivity. Hence it is a Supplying water to the crop at right time, right place and right quantity is the main objective of good irrigation management, but in case of surface water reservoirs, the irrigation water is conveyed to the farm with the conventional wide spread open channel water distribution network. In fact, the above system is not capable to meet time based crop water need due to depletion of water use efficiency of the system with age. As the time passes lot of deficiencies including low water use efficiency get involved in this type of network.
1.1. Major Findings for Low Water Use Efficiency
The following major reasons have been identified for low Water Use Efficiency of Irrigation projects Mahato (2013):
i. Poor or no-maintenance of canals/distributaries/minors of irrigation systems resulting in growth of weed & vegetation, siltation, damages in lining etc.
ii. Distortion of canal sections due to siltation or collapse of slopes resulting in some channels carrying much less and some other channels carrying much more than their design discharges
iii. Non Provision of lining in canal reaches passing through permeable soil strata; x Leakages in gates and shutters;
iv. Damaged structures;
v. No regulation gates on head regulators of minors causing uneven distribution of water;
vi. Over irrigation due to non-availability of control structures and facilities for volumetric supply of irrigation water to farmers;
vii. Poor management practices;
viii. Lack of awareness among farmers about correct irrigation practices and cropping pattern.
1.2. Poor Irrigation management
Lot of efforts is being taken to manage the irrigation effectively. The conventional wide spread open channel water distribution network, neither meet the water requirement of the crop sown in the command area of an irrigation project nor able to irrigation at right time and right place. This induces moisture stress reduces the crop yield radically.
See Case Studies of Innovative Irrigation Management ==>