Once the water-level in the Godavari river reaches the required level, pumping from the Purushottapatnam lift scheme to the Yeleru reservoir will begin.
Though the lift scheme is meant for filling the reservoir during the flood season of the Godavari to meet the water needs of the city and was inaugurated in August 2017 it could not be operationalised in time to meet that end. When it is ready for operation the water level in the Godavari is not adequate.
As a result, the Visakhapatnam Industrial Water Supply Company, like in many years in the past, resorted to pumping of water from the dead storage of Yeleru reservoir from about mid-April.
The Godavari level is 13.8 metres and is expected to touch 14.1 m, the minimum drawal level, by the end of June. “Once it happens pumping from the Purushottapatnam lift scheme is expected to begin,” said sources. Officials of VISCOW and the Irrigation Department have recently discussed the possibility and arrived at the tentative time of June-end , it was learnt.
With lifting during the flood season of four months from July to October the Yeleru reservoir is expected to be full reaching its total capacity of 24 TMC feet. Besides considerable increase in the availability in the reservoir, water flows by gravity and the pumping from dead storage will be a thing of the past.
Between 2000 and now the reservoir was full was only twice- in 2006 and 2009, say sources. The reservoir has been facing such a situation for several years with the North-East monsoon not bringing enough rain in its catchment resulting in less inflows.
However, rain in the catchment area of the Sabari, tributary of Godavari, and Sileru area is important for Godavari-level rising.
Initially lifting of around 1000 cusecs is expected from the Godavari into the first stage in the Polavaram Left Main Canal, 10 km away. From there water will flow by gravity 50 km to the second stage of the scheme. It will be lifted using eight motors and through 13 km pipeline water reaches the Yeleru reservoir.
Meanwhile, recent rain slightly improved the Yeleru reservoir level from 70.1 m to 70.4 m. Pumping will be stopped if it reaches 71.5 m. Supply to the city during the summer has been maintained with good management. Fortunately, summer had not been severe and there were a few spells of rain.
Source: The Hindu