Coimbatore will see a fall in water supply if the Kerala government is to seal a pipeline below the dead storage level in the Siruvani Reservoir, said officials of the Tamil Nadu Water Supply and Drainage Board and the Coimbatore Corporation.
The officials in Coimbatore said the Kerala Irrigation Department started preliminary works to close the pipeline, which was 17.71 feet below the dead storage level. The reservoir now had 6.39 feet of water above the dead storage, taking the overall level above the pipeline to 24.10 feet.
As the Kerala officials could not access the pipeline because of the water level in the reservoir, they might be trying to close the sump that gets the water from the pipeline, the officials in Coimbatore said, based on their observation of the preliminary works carried out in the past two days.
If the Kerala officials seal the pipeline, said to be nine feet in diameter, or the sump, the city may witness a drop in supply of up to 20 million litres a day (MLD). This loss will be felt more as the TWAD Board and the Corporation bring down the supply to ensure that the Siruvani water lasts the entire summer, until the southwest monsoon sets in.
As of Tuesday, the Corporation received 49.50 MLD. When the reservoir is full, the Corporation gets up to 75 MLD.
The officials said that once they received the news that the Kerala officials were trying to seal the pipeline, they sent their senior engineers to ask the Kerala officials to halt the work until the two governments discussed the issue. But the Kerala officials rejected their requests. Chief Engineer of the Kerala Irrigation Department K.P. Balan could not be reached for his comment.
Last year, too, in May, when the level went beneath the dead storage, the Kerala officials attempted to close the pipeline but they could not proceed. Even as they began preliminary work, rains started and forced the officials to halt the work.
The officials added that they were keeping a tab on the work the Kerala officials carried out to inform their seniors and hoped to get a solution soon.
Water experts in Chennai say the inter-State 1973 agreement on Siruvani makes it clear that any change has to be carried out only with the concurrence of the two governments. At the official level, the Tamil Nadu government has conveyed more than once to Kerala not to disturb the old pipeline, whose existence has been acknowledged in the agreement. The experts say the pipeline should not cause any worry as all flows of the Siruvani river water get measured.
Meantime, the issue has taken a political turn with members of the Thanthai Periyar Dravida Kazhagam blocking a Kerala State Road Transport Corporation bus in Coimbatore to register their protest.