The long-pending Pula Subbaiah Veligonda project, which was undertaken as part of the ‘Jalayagnam’ scheme during the tenure of former Chief Minister Y.S. Rajasekhara Reddy, is nearing completion.
But for some laborious dismantling work of about 1,000 tonne head of the tunnel boring machine (TBM), all other works including the Tunnel-I, have been completed, Superintending Engineer (constructions) N. Nagesh told The Hindu while taking stock of the progress of works at the project site in the Nallamalla forests.
“Farmers can expect the Krishna water to reach their land during the coming kharif season,” he said, adding that they have a herculean task of dismantling the head of the TMB, which would save more than ₹24 crore to the exchequer.
With a view to speed up the works, manual drilling was carried out from the other side of the gigantic Tunnel-I to a distance of 1,053 metres. As a result, the originally proposed towing of the entire TBM has been ruled out now. Now the dismantling of the TBM is being carried out inside the tunnel itself.
“The head regulator works at Kollam Vagu is also nearing completion. We will be able to draw flood waters from the foreshore of Srisailam in all probability by August,” sources in the Irrigation Department said.
As part of the project, two giant tunnels have been designed not to disturb the natural environment of the wild animals in the Nagarjunasagar-Srirsailam Tiger Reserve. The project, which originally was scheduled for completion in 2008, had suffered time and cost overruns in view of enormity of the drilling work with the TBMs procured from Germany and the U.S.
Drilling work
The government is keen on completing the Tunnel-II by August by speeding up the drilling to at least 1,000 metre a month. The work was hit due to conveyor belt issues. However, with multi-directional excavation method, the officials will be able to drill a distance of 7.5 km expeditiously, according to sources, adding that plans are afoot to drill at least 30 metres a day.
The project has been designed to draw 43.50 tmcft of flood waters from the Krishna by gravity, which can irrigate 4.47 lakh acres in Prakasam, Kadapa, and Nellore districts, apart from supplying drinking water to over 15 lakh population in the fluoride-hit parts. Nallamala Sagar reservoir has been built by closing the Sunkesula, Gottipadia and Kakarla gaps to impound the Krishna water.
