Damage to Karnataka dam forces Andhra to open two reservoirs
The massive inflow of water into the Krishna river due to the washing away of one of the crest gates of Tungabhadra dam has forced the Andhra Pradesh government to keep open the gates of its two major reservoirs – Srisailam, Nagarjunsagar
The massive inflow of water into the Krishna river due to the washing away of one of the crest gates of Tungabhadra dam has forced the Andhra Pradesh government to keep open the gates of its two major reservoirs – Srisailam, Nagarjunsagar, to let out excess water in order to prevent any pressure on these dams.
On Monday, Andhra Pradesh state irrigation minister Nimmala Rama Naidu, along with engineer-in-chief (irrigation) M Venkateshwar Rao and special chief secretary Sai Prasad went to the Tungabhadra dam site to discuss with the authorities on early completion of “stop-lock” work to prevent massive outflow of water from the dam to the downstream, putting pressure on the reservoirs of Andhra Pradesh.
Earlier, another team of experts comprising chief engineer (designs) Thota Kumar, superintending engineer Shiva Kumar Reddy and executive engineer Venugopal Reddy and others reached the Tungabhadra dam site to assist the authorities in fixing the temporary gate to arrest the flow of water.
Following the snapping of the chain of the Tungabhadra dam gate on Sunday, the 33 gates of the dam were opened, releasing approximately 100,000 cusecs of water downstream, a situation that has raised alarms among residents and officials alike. The Tungabhadra river board has issued warnings to residents in the river basin, advising them to exercise caution and avoid crossing the riverbed and adjoining canals.
Before leaving for Tungabhadra dam site on Monday, Rama Naidu told reporters in Amaravati that 2,50,000 cusecs of water was being let out from Tungabhadra dam, which was already filled to the brim. “The flood is expected to continue for another two days. The dam has to be emptied up to below the crest gate level for which 60 tmc ft (thousand million cubic feet) of water has to be released to the downstream,” he said.
The release of such a huge quantity of water from Tungabhadra resulted in swelling of water levels in Srisailam reservoir, the first major dam in Andhra Pradesh-Telangana border, which is already filled to its brim. On Monday, the inflows into this reservoir was around 1.80 lakh cusecs and the authorities were forced to let out 2,66,933 cusecs of water to the downstream by opening all its nine crest gates.
At Nagarjunsagar, the second major reservoir on Krishna river in Andhra, the inflows on Monday were 1.69 lakh cusecs. The irrigation authorities are discharging 40,278 cusecs of water to maintain the reservoir balance.
An irrigation department officials said on condition of anonymity that there is an apprehension among the farmers of Rayalaseema region of Andhra Pradesh that the decision to empty Tungabhadra reservoir up to the crest gates level by discharging 61 tmc ft of water due to the washing away of the crest gate will affect the irrigation interests of the region.
According to this official, after a series of dry seasons, Tungabhadra dam was filled to the full reservoir level by July end itself, raising a lot of hopes of the farmers in Anantapur, Kurnool and Kadapa. They took up raising of paddy nurseries in full swing in 2,84,000 acres under Tungabhadra low-level canal and another 1,16,000 acres under Tungabhadra high-level canal in Kurnool in Kharif and Rabi seasons.
“Had there been no problem with the crest gates, there would have been 105 tmc ft of water in Tungabhadra dam. Now, with the damage to the gate, it would be losing around 61 tmc. Unless there are further rains in the upstream of the river, the farmers will be at loss,” the official added.
The irrigation minister, however, said there was no immediate threat to the irrigation needs of Rayalaseema at least for this season. “If we can complete the crest gate work at the earliest, there is a possibility of storing more water in the coming days due to rains. We can still fill the dam up to 105 tmc ft,” he asserted.