21 million farmers now use underground water for irrigation of two-thirds of India's crops, and this takes out some 250 km of water per year that is only being renewed at a rate of 100 km³ per year (New Scientist, 2006). Currently it is estimated that around one million new groundwater pumps are installed annually to increase crop irrigation. Not only are there no data on the distribution of the pumps, but they are entirely uncontrolled as well as being subsidised by government. There are associated problems between states over the management of transboundary water resources; these are expected to worsen in the future, with a growing disparity between supply and demand for water (Shadananan Nair, 2004). There are further problems connected with the overexploitation of groundwater, brought about by the increasing use of small motorised pumps. In 2000, India's 81 million land-owning families had some 20 million tube wells and pump sets, a figure that grows by 500 000 per year. Unregulated use and cheap electricity has depleted aquifers, which has meant ever deeper wells and increased costs. This also poses severe problems for rural water supply, as these wells are the major source of drinking water. In addition there is concern over leachates from agriculture causing increasing aquifer pollution. The pollution and deterioration of groundwater in many areas is a matter of increasing pubic health concern, as is the quality of many of the rivers used by municipal authorities for drinking water supply, which are heavily polluted (TERI, 2002). Although there is a strong central government, the lack of constitutional powers makes it weak with respect to the co-ordination of the water sector. That leaves the sector and its institutions relatively constrained in what they can achieve in terms of planning and water management (Brisco, 2005). National water supply and sanitation strategies are set out in successive five-year plans. The nodal agencies for rural and urban water supply and sanitation are the Rajiv Gandhi Nation