SALEM: It is official. Mettur Dam will not be opened for Cauvery delta irrigation on June 12, the customary date. Officials estimate that in the given conditions and on the basis of rainfall predictions, the opening could go beyond middle of July.
Officials with the PWD Water Resources Wing, Mettur Dam Division, confirmed that a report was submitted on Saturday to the State government on the storage position of the dam and the other vital parameters.
According to the report, the dam held merely 5.2 tmcft of water as against its full capacity of 93.5 tmcft. The water level, as on Saturday, stood at 23.68 feet as against its full height of 120 feet. Technically, it required a water level of at least 90 feet and storage of 45 tmcft to open the dam for delta irrigation.
For the sixth consecutive year, the opening date was postponed. The story behind the trend may be told in many ways, but water managers saw the last irrigation year as one of the worst. Both monsoons failed and the inflow into Mettur Dam came in trickles. The dam could not be opened for Cauvery delta irrigation on June 12 because of poor storage. It was after the Supreme Court order, Karnataka released water and the Mettur Dam was opened on September 9, 2016 for Cauvery delta irrigation.
However, Karnataka could not sustain water release from its reservoirs and amidst intense row, the Centre sent a high level Cauvery Technical Team to Tamil Nadu and Karnataka to report on the ground realities in both the states with respect to water availability and the requirement of farmers. The Team visited Mettur Dam on October 9.
While the matter was being dealt at the politico-legal front, the monsoon also failed. Mettur Dam normally received its maximum inflow during this season.
The dam received 69 tmcft water as against the Cauvery Tribunal stipulated quantum of 192 tmcft.
The inflow during the summer months dropped to two digits.
The leftover stock of water was discharged for drinking water purpose at a rate of 500 cusecs per day. Thus, the storage dropped to single digits nearing the dead storage level (At five TMCFT, the storage is treated as dead).
South West monsoon rains began in Kerala in the last week of May this year.
The local catchments of Mettur Dam saw good rainfall with flash floods in Cauvery tributaries.