VIJAYAWADA: An expert panel of the National Hydro Power Corporation (NHPC), in a report submitted to the Polavaram Dam Design Committee recently, proposed that construction works of the main dam cut off or diaphragm wall be completed between January and June 2018.
It recommended jet grouting works for the lower cofferdam during the same time along with earth and concrete works for the spillway. Jet grouting for the upper cofferdam would be taken up as per the final design.
During the flood season in the Godavari between July and October 2018, spillway works, gate works, spill channel and approach channel works should be completed. Among the recommendations made were completing works on the lower cofferdam, the 1,100 meters long main dam foundation treatment and upper cofferdam in the period from November 2018 to June 2019.
By July 2019, the main dam at the height of 53.2 metres should be completed along with the powerhouse complex. According to sources, two proposals for the upper cofferdam were recommended: one is of 1,660 metres long and another of 1,150 metres.