Impact of Tank Restoration Programme (Mission Kakatiya) on Groundwater Regime, Telangana State, India: A Case Study from Stressed Hard Rock Aquifers.

In 2015, to enhance the development of agriculture-based income of small and marginal farmers through sustainable irrigation sources, restoration of 27,472 tanks on massive scale was initiated by the Government of Telangana with people's participation. Ground water department monitored water levels and water quality of 172 wells identified from 9 overstressed watersheds in the state and studied the impact of tank restoration on groundwater regime for 6 years. Well hydrographs of monitoring wells reflect a rising trend of 0.80 m/year to 2.87 m/year in different watersheds with an average of 1.27 m/year. The trends have demonstrated an 19% more rise (average) in the influence zone as compared to the wells in non-influence zone. A significant improvement in groundwater quality in the influence zone was observed as the concentration of total dissolved solids (TDS), chloride (Cl−), nitrate (NO3−) decreased in the range of 5.8 to 91.1 mg/l/year (average, 7.7 mg/l/year); 1.4 to 33.1 mg/l/year (average, 5.3 mg/l/year) and 0.9 to 16.9 mg/l/year (average, 3.6 mg/l/year) respectively, while the bicarbonate (HCO3−) showed significant increasing trend ranging from 1.3 to 47.2 mg/l/year (average, 16.6 mg/l/year). HCO3−/Cl− ratios suggest more freshening of groundwater in tank influence zones than in non-influence zones. The tank restoration programme increased groundwater storage and thus provided an increase in land and agricultural productivity. It is recommended to bring policy initiatives for taking up such massive tank restoration programmes in similar geoenvironments by involving people at the village level, to sustain the long-term positive impact and to address the water requirements of people all over the country. [ABSTRACT FROM AUTHOR]