Thanks to active monsoon, Mettur dam brims for record 79 days this year

Almost six decades ago, the dam remained in its full reservoir level (FRL) for a maximum of 92 days for the whole year with intermittent breaks. Also, this year, the dam had brimmed continuously for 42 days, since the dam got filled up last on 11 November.

“After about 42 days, the water level dipped to 119.740 feet from its FRL of 120 feet only on Monday at 8 am following an increase in its outflow for delta irrigation,” said a PWD official.

The outflow, which remained at 3,500 cusecs on Saturday, has been increased to 12,000 cusecs for irrigation purpose in the delta region. Earlier, the discharge from the dam was maintained low as water requirements for delta irrigation was met out by rains.

With rains slowing down, the farmers sought to increase the discharge to irrigate crops spread over in 16 lakh acres in 12 districts along the Cauvery river basin. However, the inflow into the dam has gradually reduced to 3,939 cusecs on Monday from 4,100 cusecs on Sunday. It was 4,843 cusecs on Monday last week.

The dam first got filled up on September 7 and continued to be in its FRL till 21 September. After about two days, the dam again reached its brim and remained full for about six days till 29 September.

Then, there was some lull in inflow for a few weeks until the North East Monsoon picked up pace helping the water level in the dam to reach its full capacity on October 23 and remainedso till November 7.

For the fourth time, the dam touched its 120 feet mark on November 11 and had its full capacity until December 22, continuously for about 42 days. It was in 1975 last that the dam remained in its FRL continuously for about 45 days. Similarly, in 1959 that dam remained in its brim for a total of 92 days for the whole year with intermittent breaks.

For the second consecutive year, the dam has received surplus water from Karnataka due to active monsoons bringing copious rains in its catchment areas.

“Till Monday this year, the Mettur dam has received a total of 256 tmcft, which is 79 tmcft more than the prescribed quantum of water to be released by Karnataka. Tamil Nadu is entitled to receive 177.25 tmcft in a year. Last year the dam received a surplus inflow of nearly 199 tmcft due to heavy rains. The outflow from Mettur dam has also crossed 172 tmcft so far,” the officialadded.

The PWD official hope that there would not be any issues in releasing water for samba cultivation from the dam on its customary date of June 12 next year. “In the existing scenario, there wouldn’t be any issues in opening water from the dam for delta irrigation in June, 2020,” the official said.

The dam has missed its customary date consecutively for the last nine years due to poor storage. The dam was last opened on the exact date onJune 12 in 2011.