TN needs to act fast to save its flood waters

Chennai | Updated: Nov 14 2005, 06:08am hrs
In a year of good rains, about 200 tmc ft of water flows into the Bay of Bengal from the Tamil Nadu river basins, according to experts. Of this, 11 tmc ft is from water-starved Chennai alone. Last week, too, huge quantity of water flowed into the sea, after inundating vast areas in the city.

This is a sad state of affairs in a state which, for centuries, has had one of the best traditional rainwater harvesting and distribution management systems. The signal from the current rainy season and its aftermath is loud and clear the state has to act now to implement the recommendations of the committee appointed to assess and suggest measures to utilise the monsoon floods and outflows to sea, says CS Kuppuraj, a former public works department chief engineer, and one of the members of the committee. The committee was appointed in October 2001 and submitted its report in six months. The intervening years saw only drought. But when the floods came, the state was least prepared.

Tamil Nadu has two well-defined rainy seasons. It has 33 river basins from Araniar in the north to Kodaiyar in the south. Cauvery is the largest and most important basin. From these river basins, the committee has estimated that over 200 tmc. ft water is wasted into the sea. Half of this is from the Cauvery basin. The committee has, therefore, recommended actions for water conservation and groundwater recharge.

One of the policy changes suggested is to change the dependability norm to 25% from 50%. This means that the government should take up a project even if there are rains and floods once in four years.

The key recommendations of the committee are construction of new reservoirs, new check dams and new barrages. It has also suggested that there should be inter-linking of river basins. All these would cost over Rs 2,000 crore. Compare this with the Rs 1,000 crore spent on the New Veeranam project to pump about 1 tmc ft of water for six months, or Rs 400 crore for the Minjur desalination plant to supply 100 million litres daily. It will take 200 days running of the plant to get about half tmc ft of water, Mr Kuppuraj told FE.

He believes that with the proposed investment, the state can save at least 100 tmc ft of water and avoid most of the flood havoc. It would also regenerate lost aquifers all over the state. The government also needs to act on the order of the Madras High Court to restore water bodies to their original position. The court, in its order on June 30, 2005, has called for ruthless and pitiless removal of all structures encroaching on water bodies all over the state.