Dry spell and rising mercury level worrying authorities

Will the city continue to get its regular drinking water supply till the next monsoon sets in?

The Corporation may struggle to maintain the current 115-MLD (million litres a day) water supply if summer showers do not add to the inflow and increase the storage in Vaigai dam. Last month, Mayor V.V. Rajan Chellappa exuded confidence that the administration would manage to maintain the regular supply till June 1. However, the continuous dry spell and rising mercury level are worrying the Corporation and Public Works Department.

“We are facing a drought after 10 years. The last dry spell occurred in 2003,” a senior PWD official noted.

The present storage of Vaigai dam (1,822 mcft as on Monday) was dropping by around 9 mcft every day owing to the water supply for the city and Andipatti-Sedapatti combined drinking water projects. These projects would require not less than 1,100 mcft of storage for the next 110 days (till June first week), according to PWD sources.

With the district getting only around 50 per cent of its average annual rainfall, the groundwater too is fast depleting. “As the groundwater table is going down, the borewells are failing to pump adequate water, forcing city residents to depend more on piped water supply for all their household needs,” another official said.

Meanwhile, the depleting water level in the Vaigai riverbed was threatening the water supply to extended areas of the city such as Tirupparankundram, Harveypatti, Tirunagar, Vilangudi and Avaniapuram. These areas have their infiltration wells on the riverbed from where they draw water. The Corporation was taking steps to ask the PWD to release water from Vaigai dam to augment the water source of the wells.

Likewise, the infiltration wells of water schemes of Dindigul, Sivaganga and Ramanathapuram districts that were on the Vaigai riverbed too were showing signs of failure. “If similar demand comes from Sivaganga and Ramanathapuram districts for water release, at least 750 mcft of water from the Vaigai credit would vanish making it tough for the city,” the PWD official said.

Besides, dead storage of around 200 mcft of water has to be reserved for the Chithirai festival. The PWD has to release 150 mcft of water when Lord Kallazhagar enters the Vaigai riverbed in April. “These events need not less than 1,000 mcft of water, leaving the city and Andipatti and Sedapatti high and dry,” the official added.

As a result, the Corporation, which had decided to sink two borewells each in the 28 newly-added wards of the city last month, is now planning to dig four borewells in each ward to offset scarcity during summer.

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