Saving water and energy in agriculture in Upper Ganga River Basin (UGRB)

With increasing demand on water resources for multiple uses, it is estimated that most of India's river basins could face severe deficit by 2030 with some of the most populous – including the Ganga, the Krishna, and the Indian portion of the Indus – facing the biggest absolute gap. This may further worsen the depletion of ground water resources and fossil fuel and unavailability of water for development objectives leading to erosion of economic, social benefits and the livelihood opportunities. Climate change has further added to uncertainty to these estimates suggesting greater factor of safety in projecting water gap.

Water use in agriculture is around 83% of total water use in India and there are good possibilities of saving water in agriculture sector. As irrigation with ground water has mushroomed as a source of independent as well as supplemental to canal irrigation, particularly in Ganga Basin, any saving in water consumption will lead to saving of associated energy also.

This paper is based on a research study sponsored by WWF under ‘Living Ganga Programme’ which was carried out in the year 2010–11⁽¹⁾. The results of the study indicate that current energy and water use efficiencies in Upper Ganga River Basin (UGRB) are very low and even a moderate increase in the use efficiencies can provide for required environmental flows to river Ganges in addition to diversion of substantial water savings to other development sectors. It will also save huge amount of fossil fuel and electricity leading to cleaner environment.

In a nutshell, planned withdrawals from Ganges by canal systems in UGRB are around 43080 cusec in Kharif and 19000 cusec in Rabi seasons (total around 27.3 BCM per year). The overall efficiency of a typical representative canal system, namely, Kanpur Branch Canal has been computed under this study as 29.2%. Extrapolating these results to Upper Ganga River Basin, It is estimated that 19.33 BCM water drawn directly from Ganges fails to irrigate the intended crops and ends up in evaporation or recharging of the basin aquifers. Reuse of this water for agriculture through ground water pumping requires the additional use of fossil fuel/electricity.

In Upper Ganga River Basin (UGRB), irrigation from ground water is provided through 950000 shallow diesel pump sets and 134000 electric pump sets owned by the farmers and 5871 deep state tube wells owned by the Irrigation Department. The overall energy efficiencies of tube well irrigation systems range from 5.4% to 29.0%.

It has been established through the findings that if we could only improve the existing water and energy use efficiencies by merely 10%, there are possibilities of saving 2.26 BCM of water in UGRB besides saving of 195 million litre of diesel and 0.52 million tonne of Carbon-Dioxide emission.

To achieve envisaged savings demand management as well as change management strategies have been suggested in this paper.