Climate change will affect water supplies in south Asia, where high-intensity floods and droughts are expected in the future. Increasing water storage is a key adaptation strategy, and the experience of irrigation tanks illustrates both the potential and challenges of this adaptation response.
The analysis presented in this paper shows that in water-scarce regions of India, run-off harvesting does not offer any potential for groundwater recharge or improving water supplies at the basin scale. The issues are many: (1) Water harvesting in the
Society for Promotion of Wastelands Development (SPWD) has been working in the Rayalseema reion of Andhra Pradesh since the mid 1990s on restoration of Panchayati Raj tanks. Around 40 tanks have been restored in the region by SPWD in collaboration with local Non Government Organizations (NGOs), through formation of representative community-based Tank Management Committees (TMCs).
Uncertainty in the occurrence of rainfall with respect to time and quantity is a major contraint to agricultural production in rainfed areas. To alleviate the constraint, groundwater is pumped at an unsustainable rate causing continuous water table decline. Groundwater recharge by the rainwater and runoff harvested in percolation tanks can augment the groundwater resource.
