Western TN stares at crisis as dam storage plunges

With rain playing hide and seek, even a week after the onset of South West Monsoon, the existing water in reservoirs were also fast depleting causing concern among water managers.

 The long dry spell has cast a crisis for Coimbatore as the Siruvani Dam, a main source of drinking water, remains pathetically meager at just 2.03 feet above the dead storage level. 

“It’s just a drizzle of disappointment as the catchments received only mild showers ever since the monsoon began. Only on Saturday, there was a moderate 13mm of rains, which helped in maintaining the storage level from going down further below the dead storage level,” said an official. 

In 2017, the water table went precariously below the dead storage level and water has to be pumped from the dam. While 101.4 MLD of water can be drawn from the dam, water supply has been reduced sharply to 38 MLD per day due to evasive rain. Yet, the official sounded positive that the storage level may improve once rain start in the coming days. 

The Siruvani dam last overflowed, when the South West Monsoon brought heavy rain resulting in floods in Kerala during August last year. 

Similarly, the Sholayar dam, one of the deepest reservoirs, has almost been reduced a cesspool. Its storage now remains in single digit of around five feet as against its full reservoir level of 160feet. 

“Exactly on the same day on Sunday last year, the dam had storage of 134.31 feet. The dam filled up fast and even overflowed several times as the monsoon began in advance and brought heavy downpour last year,” said an official.   

A vital reservoir under the Parambikulam Aliyar Project, the Sholayar dam mainly serves irrigation needs and for power production. Also the Bhavanisagar Dam, one of the world’s largest earthen dams, has 55.02 feet as against its full storage level of 105 feet. Yet, the dam holds just 5.7 TMC as against its full capacity of 32 TMC. 

On this day on Sunday last year, the dam almost had double this capacity with 11.6 TMC (71.74 feet) and its inflow then was at its maximum of 6,840 cusecs. The current inflow is a dismal 413 cusecs. About 200 cusecs is drawn from the dam daily for drinking water requirements. 

It is no better in the Stanley Reservoir in the Mettur dam as a week after recording a surge in inflow following rains in catchments, the inflow has now started to decline gradually. The inflow remains less than 500 cusecs as against 919 cusecs on June 9. 

The storage level also hovers around 45.2 feet and there is no immediate possibility to open the sluices of the dam for irrigation in delta districts. The official also added that he is yet to receive any communication on release of water from dams in Karnataka as per the direction of Supreme Court. 

With water level in reservoirs dipping faster, the water managers have downed water supply to residential areas, resulting in sporadic break out of protests by people across Western districts. 

The Agro Climate Research Centre in Tamil Nadu Agricultural University (TNAU) has predicted normal rains for Coimbatore in the South West Monsoon.