JOIN USThe State government has tied up with a private firm, Farmland Rainwater Harvesting Systems, to construct injection wells to recharge groundwater by harvesting rainwater.
The firm has so far constructed over 350 recharge wells in the State under the Rural Development and Panchayat Raj schemes in several districts and over 30 injection wells in the City, mainly on IT campuses and offices, which claim to have seen exceptional results.
According to Vijay Raj of the firm, the V Wire technology adopted by the company has yielded good results. He said that in the conventional method, the depth of recharge point is limited to just around three metres and the rainwater is normally let directly into the borewell. In V Wire, the injection wells are constructed close to the borewell where the depth of recharge point varies from a minimum of 20 metres to 60 metres, depending on the soil profile.
The conventional method can cause adverse environmental impact in terms of waterlogging and soil salinity. “We are blindly following the method used in Chennai which is not suitable for Bangalore.
The City has more clay content in the top soil which makes it hard for water to seep in and percolate, whereas in Chennai, water easily percolates in sandy soil,” added Vijay. In V Wire technology, as the depth of the recharge point is more than 150 feet below the ground, water gets purified, with reduced salinity, hardness and fluoride contents.
A team led by Reema Parekh, programme coordinator from the Centre for Environment Education, evaluated the injection wells in various villages across Chamarajanagar, Chikkaballapur and Tumkur.
“Wherever these injection wells were constructed, the yield has improved. Similarly, many farmers too claimed that their farmland borewells were replenished,” she added.