The Water Resources Department is identifying more locations to construct minor check-dams across the tributaries of the Palar River. The proposal to construct such structures follows the recent success of check-dams built in Kancheepuram and Chengalpattu districts.
The department plans to build small storage structures, particularly at over-exploited zones — where groundwater extraction rate is higher than that of recharge. Officials of the WRD said two check-dams – one across the Ongur River near Vanniyanallur village in Chengalpattu district, and one at Sempoondi across the Killiyar River in Madurantakam taluk – were recently constructed. The waterways continue to have a flow near these check-dams since October last year, they said.
Vanniyanallur village, and some of the nearby villages, fell under over-exploited zones, necessitating the need for a check-dam. Now, nearly 212 hectares of land yield harvest twice a year.
Following the construction of the check-dam, the over-exploited zones have now registered significant groundwater recharge. The quality of groundwater in the wells has also improved, and addressed the drinking water needs, said officials.
The check-dam, which was built at a cost of ₹4.75 crore with the assistance of the National Bank of Agriculture and Rural Development, stores nearly two million cubic feet of water and retains flow for nearly 300 metre on the river. This is enough to sustain groundwater reserves for more months in a year; increase agricultural productivity and meet the drinking water needs of residents, they added.
Similarly, the check-dam across the Killiyar River at Sempoondi has benefited nearly 90 hectares of land, enhancing water supply for irrigation and drinking in a minimum of five villages.
“We are looking for possibilities to build more such check-dams in the Palar tributaries. These recharge structures can be built quickly, and have a lasting impact. The livelihood of farmers in the villages surrounding the check-dams has improved,” an official said.