As many as 3,600 tanks in Kancheepuram and Tiruvallur districts, if properly preserved and networked, can provide five times the quantum of water that Chennai requires in normal times.
The estimated water that could then be harnessed through the tanks will be about 80,000 million cubic feet (TMC), according to a proposal mooted by veteran water expert S. Janakarajan.
Ordinarily, Chennai Metrowater supplies 830 million litres a day (MLD). The annual requirement would be around 11,000 million cubic feet (TMC). Besides, an allowance of five TMC has to be provided annually for evaporation.
For the purpose of calculation, five reservoirs – Poondi’s Satyamurti Sagar, Cholavaram and Red Hills, all in Tiruvallur district; Chembarampakkam tank in Kancheepuram and Veeranam tank in Cuddalore – are considered. The combined storage of the reservoirs comes to around 12.4 TMC and the last two tanks are not exclusively meant for Chennai.
As per the proposal, 1,350 out of 3,600 tanks have been identified, their database digitised and the cost estimates prepared. In view of rapid urbanisation in the neighbouring districts of Chennai, the utility of these tanks for agriculture has shrunk drastically over the years. By implementing the proposal, the tanks will not only be preserved but also used to meet the growing requirements of the city.
Averting disasters
The repeat of the devastating floods witnessed by the city and suburbs in December 2015 can be “effectively reduced,” states the proposal.
The proposal along with some others will shortly be submitted to the State government, according to P.R. Pandian, chief of the Tamil Nadu Federation of All Farmers’ Associations.
He has also taken the help of two former senior engineers of the Public Works Department, A. Veerappan and Elango.
An improved version of Athikadavu-Avinashi groundwater recharge scheme in the western region of the State, rehabilitation of five anicuts and channels of the Aliyar river system in Pollachi taluk of Coimbatore district, and a new system of treatment of domestic and industrial waste water form part of the set of proposals.
