Polavaram Spillway gates operated successfully for the first time amid flash floods

The Polavaram flood water release spillway system, which is the lagest in the world has been operated successfully in its first season by lifting 48 hydraulic gates in a very short time. The hydraulic gates to control the flash flood lifted and simultaneously released 15 lakh cusecs of water through the spill channel into the Godavari in less time.

It is known that the Polavaram project is still under construction and all major works on the spillway have been completed by setting up hydraulic gates that can be operated automatically to release the flood water. The lifting of all 48 gates proved their efficiency and the role of gates became crucial in releasing flood water easily into the Godavari through the approach channel, spillway, spill channel, and pilot channel for 6 km.

The Godavari has had a record flood in 100 years due to rains and irrigation officials said that this is the first time in the history of 100 years that the Godavari has been flooded. However, the Polavaram project has been prepared in advance to withstand heavy floods from the top and all arrangements have been made to release the flood water from the spillway to the bottom. 48 ​​gates and 42 radial gates were installed in the spillway along with the installation of 4 hydraulic cylinders to lift them. Similarly, 24 power pack sets were also installed on the spillway and the gates were operated.

Polavaram project will have radial gates along with river sluice gates at the dead storage level. A total of 10 river sluice gates, each with 20 hydraulic cylinders two per gate, and 10 sets of power packs to operate. The flood approaching the spillway is first released through the river sluice gate and when there is dead storage in the reservoir, the gates are raised and water is released downstream to provide drinking and irrigation water to the Godavari delta.

It is known that the Polavaram spillway is designed to release 50 lakh cusecs of flood water downstream through 48 radial gates. which is greater than the Trigarges Dam in China that is designed to release 41 lakh cusecs of flood water. Apart from that, experts have designed the Polavaram spillway and gates based on 100 years of history

Megha Engineering Institute CGM M. Muddukrishna said that the Godavari has a history of 36 lakh cusecs of flood in a hundred years, so the spillway and gates of the Polavaram project have been designed to withstand a flood of 50 lakh cusecs. "Each radial gate is 16m wide, 20m long, and weighs 300 metric tons, and 432 tmcs of flood water per day is discharged downstream. Radial gates of Polavaram project have been designed with release capability," Muddy Krishna said

Polavaram project has 96 hydraulic cylinders for 48 radial gates and 24 power pack sets to operate them. Two gates can be operated with the help of one power pack set. Similarly, if there is any technical problem while operating the radial gates or any obstruction to the gates, the staff first logs the gates and removes the obstructions or technical problems. After solving, the radial gates will be operated for which 5 sets of staff log elements have been kept ready in the Polavaram project. They have been designed with a width of 17m and a height of 21m.

Currently, log gates are also available in full range. However, the spillway radial gates have been fully prepared to withstand the heavy flood coming to the Polavaram project and release it downstream. At present, more than 15 lakh cusecs of flood water are being released downstream from the Polavaram spillway gates.