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The Uttar Pradesh government's experiment to recharge excess river water, via earthen canals, has succeeded in raising the water table and bringing down cultivation costs
The Uttar Pradesh government's experiment to artificially recharge groundwater has opened up a new and practical way to conserve and rejuvenate falling groundwater reserves. The project -- the Madhya Ganga Canal Project (MGCP), which occupies lower Ganga canal commands -- was initiated in 1988. It has succeeded in raising the water table, thereby reducing pumping costs for irrigation. In 2000, the International Water Management Institute (IWMI) carried out a study on the Lakhaoti branch canal of the MGCP, to assess the impact of the diversion of surplus Ganga water, during the kharif season, on groundwater levels and cropping patterns. The Lakhaoti branch is spread over 205.6 thousand hectares and covers the districts of Ghaziabad, Bulandshahr and Aligarh in western Uttar Pradesh. It is bound by the drainage canals of the Kali and Nim rivers. According to the study, the canal project has helped raise the groundwater table to 6.5 metres, and brought down the cost of pumping for irrigation from Rs 4,500 to an economical Rs 2,700 per ha metre. Earlier, farmers used to pump water to irrigate their crops even during the monsoons. This lowered groundwater levels causing severe water shortages during the dry season. Following the introduction of the MGCP project, seepage from the canals and fields helps recharge underlying aquifers. The irrigated area in the project region has increased from 1,251 ha in 1988-89 to 35,798 ha in 1997-98. In 1999-2000, the area under paddy irrigation was 14,419 ha. Thanks to the canal, the total annual cost of cultivation has declined from Rs 1,02650 to Rs 93,600. One of the conclusions drawn from this experiment has been that the traditional practice of supplying water only during the dry season needs to be changed. Instead, adequate water should be supplied during the monsoons too, to help farmers grow water-intensive crops such as rice and sugarcane. This way, irrigation and the recharge of groundwater aquifers can take place simultaneously. Also, it will help reduce the risk of a poor monsoon: farmers are guaranteed sufficient water both during the monsoons and post-monsoon. The MGCP was able to meet demand for domestic (2,397 ha m in 1997-98) and industrial uses (1,797 ha m in 1997-98) from recharged groundwater. The general belief is that despite some nearly 800,000 big and small dams worldwide, the reservoirs capture and store only about one-fifth of all rainwater. The bulk of it runs off into the sea. According to the Indian National Committee on Irrigation and Drainage (INCID), India has built more than its share of the world's dams. But 1,150 km3 of its rainwater still empties out into the sea annually, in the form of `rejected recharge' (INCID 1999). If we could store a fraction of this underground, by artificial recharge, groundwater supplies would increase significantly. The Indo-Gangetic plain experiences between 650 and 1,000 mm of rainfall annually. Only 200 mm of this percolates the soil to replenish underlying aquifers. Most of the rainfall is not absorbed into the already saturated soil and eventually flows unused into the sea. The MGCP helps prevent this runoff. Though in its nascent stage, the Lakhaoti branch system could serve as an example of how monsoon water can be stored in subsurface reservoirs without the need to construct dams. And, how farmers' livelihoods could substantially improve in areas that have similar hydro-geological characteristics as those of the western Indo-Gangetic plain. The project shows how equity and efficiency in water use can be achieved by proper electricity pricing and the regulation of groundwater. Contact: Dr R Sakthivadivel
-- C/o IWMI, Elecon
-- Anand-Sojitra Road
-- Vallabh Vidyanagar 388 001
-- Gujarat (InfoChange News and Features, July 2003)
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