Spillway discharge of flood at Srisaialm dam, the common reservoir for the two Telugu States of Telangana and Andhra Pradesh, commenced on Wednesday evening as the project authorities operated two crest gates and lifted them for 10-foot height each to let 53,600 cusecs of water fall majestically into the bucket and rebound into the air before falling into the river course.
The engineers of the project performed a ritual (puja) before switching on the motors to operate the gates after 6.30 p.m. as the water storage in the reservoir crossed 200 tmcft against its capacity of 215.8 tmcft and water level crossed 882 feet against the full reservoir level of 885 ft. Along with the spillway discharge, another 65,000 cusecs water was also being let into the river with power generation in the left bank power house of Telangana and right bank power house of Andhra Pradesh.
According to the dam authorities, the spillway discharge in July this year has taken place for the first time after 2007 due to flood reaching from the second week of June. Last year, the spillway discharge of flood could begin on August 19 and on August 9 a year before that (2019). The dam was getting over 4.16 lakh cusecs flood being released at Jurala and Tungabhadra dams in the upstream.
Power generation
“But for the release of nearly 50 tmcft of water with power generation by Telangana so far this water year (from June 1), Srisailam dam would have become surplus much earlier. Telangana has taken up power generation by operating one unit of the 6×150 megawatt power house initially, in the first week of June,” a senior engineer at the dam site told The Hindu . After July 19, the generation has been in two to five units.
About 55.3 million units of energy was generated in the left bank power house during June and another 226.37 MU this month, till July 27. Hydel generation in the right bank power house commenced on July 27 as AP was opposing generation by Telangana till the last week.
As of Wednesday evening, the upstream reservoirs from where Srisailam is getting flood were all getting sizeable volume of water. Almatti was getting 4.14 lakh cusecs and discharging 3.8 lakh cusecs. Similarly, it was 4 lakh cusecs n 3.87 lakh cusecs at Narayanpur, 3.82 lakh cusecs and 3.85 lakh cusecs at Jurala and 81,000 cusecs and 50,000 cusecs at Tungabhadra, respectively.
In the Godavari Basin, Sriramsagar was getting 12,800 cusecs inflow and Yellampally was getting 16,200 cusecs. Singur (1,750), Nizamsagar (679), Lower Manair (3,800), Kaddam (1,300 cusecs) were also getting inflows in a small measure. In the downstream, Medigadda Barrage was getting 1.43 lakh cusecs flood and discharging 1.46 lakh cusecs.
