History of N.Sagar Tailpond

Nagarjuna Sagar tail pond is a multipurpose reservoir located 21 kms downstream from the Nagarjuna Sagar Dam across the Krishna River near Satrasala in Guntur district. It’s gross water storage capacity is 6 Tmcft The reservoir water spread area extends up to the toe of the Nagarjuna Sagar dam. The project is under construction and expected to be completed by July 2014.

Hydro electricity generation 

Two units of 25 MW each hydro power generation units are under construction to utilize the head available across the dam from the river flood water and the water released to Prakasam Barrage requirements.

Peaking power generation

Presently, the 700 MW reversible hydro turbines (7 x 100 MW) located at the toe of Nagarjuna Sagar Dam are unable to operate in pumping mode due to non availability of tail pond for storing the released water during the power generation mode. With the completion of tail pond, surplus electricity from the electricity grid would be used for pumping the water back to the Nagarjuna Sagar reservoir and recycled for meeting peaking load on daily basis. Thus surplus electricity is consumed when it is available and used to meet the peak electricity requirements without letting the water out of the Nagarjuna Sagar tail pond. 700 MW peaking power for eight hours duration can be met with one Tmcft of live storage water available in the tail pond.

Irrigation potential 

200 Tmcft surplus water annually from the Godavari River is planned to be fed in to this tail pond by the Dummugudem Lift Irrigation Scheme which is under execution. The water transferred to this tail pond will be pumped to the upstream 410 Tmcft gross water storage capacity Nagarjuna Sagar reservoir to feed its right and left bank canals. Thus Nagarjuna Sagar reservoir need not receive the water supply from the upstream Srisailam reservoir.The retained water in the Srisailam reservoir would be used for upstream water uses from Jurala and Srisailam reservoir for irrigation needs in uplands of Telangana and Rayalaseema regions. The water from the Nagarjuna Sagar reservoir can also be pumped to the Srisailam reservoir by left bank Srisailam hydro electric power station (900 MW) in pumping mode in case of severe drought in Krishna river basin. Kalwakurthi lift irrigation project, Rajiv Bhima lift irrigation project, Nettampadu lift irrigation project, Kollapur lift irrigation project, Srisailam Left Bank Canal, Telugu Ganga irrigation project, Handri Neeva lift irrigation project, Galeru Nagari irrigation project, Veligonda irrigation project etc. which are in advanced stage of construction are depending on the Krishna river water available at Jurala / Srisailam dams.