Gandikota Reservoir and the GNSS water network

Gandikota in the GNSS network

Gandikota stores water on the Penna and also serves as a major junction in the Galeru Nagari Sujala Sravanthi system. Krishna water reaches it from the Srisailam side through the right bank system, Gorakallu and Owk. From Gandikota, water can move toward Paidipalem, Chitravathi and the lower GNSS reservoirs. Its 26.85 TMC capacity is therefore only one part of its importance to Kadapa. ^{[2][3][9][13]}

Current irrigation planning also depends on how quickly water can be carried through the upstream system when Krishna flood flows are available. That makes conveyance capacity as important as the storage available at Gandikota. ^[15][16][17]

From proposal to a working reservoir

Gandikota appears in the irrigation record well before the Jalayagnam period. Andhra Pradesh budget records place Galeru Nagari in the state programme by 1989. A 1996 budget record names Gandikota in a combined allocation. In 1999 the state said sanction had been accorded for Gandikota Reservoir with an irrigation objective of about 70,000 acres in the then Cuddapah district. ^[6][7][8]

Implementation accelerated in the 2000s. GNSS Phase I received major administrative approval in June 2004 and state planning records show works under implementation in 2004 to 2005. Later feasibility material places completion of the dam works in 2012 to 2013. A Government of India inspection records the public inauguration on 22 September 2018. These dates mark different stages in the project. ^[1][2][3][9]

Expansion during the YSR government

Dr. Y. S. Rajasekhara Reddy’s government became a major implementation period for GNSS and the connected lift systems. In May 2009 he reviewed GNSS, Gandikota Lift Irrigation, Chitravathi, Pulivendula Branch Canal and other Kadapa irrigation works. A second review in August included GNSS Phase I, Gandikota Lift Irrigation and the Gandikota to Chitravathi works. ^[10][11]

Road replacement, village submergence, lift systems and command area works continued alongside construction. These works became part of the practical process of bringing the reservoir and its connected irrigation system into fuller use. ^{[5][9][10][11]}

Dam, storage and spillway

Project feasibility material gives Gandikota a Full Reservoir Level of 212 metres and a Minimum Drawdown Level of 202.9 metres. Gross storage is about 760.30 million cubic metres, equal to 26.85 TMC. The 2021 feasibility report lists live storage at 669.38 million cubic metres, about 23.639 TMC, with dead storage of 90.93 million cubic metres. The 2025 Central Water Commission dam register lists live storage at 631.465 million cubic metres, about 22.30 TMC. The two official publications use different live storage figures, so both are identified by source. The feasibility report also gives a water spread of about 10,773.89 hectares at Full Reservoir Level. ^[3][4]

The feasibility report describes a concrete lower dam about 320 metres long at the top and about 25.2 metres high from river bed level. The CWC register records 325 metres and 25 metres. Both sources give a designed spillway capacity of 8,180 cubic metres per second. The feasibility report describes a free flow ogee spillway with 14 bays. The spillway allows Gandikota to handle flood flows on the Penna as well as store water. ^[3][4]

Krishna water route to Gandikota

Transferred water reaches Gandikota from the Srisailam side through Gorakallu and Owk. The Government of India GNSS inspection records the flood flow canal from the Owk foreshore toward Gandikota as completed and carrying Krishna water. ^[2][3]

Gandikota also receives natural basin inflow, including contribution from the Chitravathi River recorded in project feasibility material. A separate lift system carries stored water in the opposite direction from Gandikota toward Chitravathi Balancing Reservoir. ^[3][9]

Distribution beyond Gandikota

The Gandikota Lift Irrigation Scheme moves water toward Paidipalem and the Pulivendula side. Another staged lift system carries water toward Chitravathi Balancing Reservoir. Farther down the GNSS chain, Vamikonda and Sarvaraja provide smaller balancing and distribution storages. Together these reservoirs show how water moves from a large regional storage into local irrigation networks. ^{[3][5][9][13]}

Rehabilitation and full storage

Fuller impoundment at Gandikota required road replacement and rehabilitation in villages affected by submergence. In June 2020 the Water Resources Department sanctioned ₹522.85 crore for affected and displaced families in seven villages. The government order linked the payment with the objective of impounding the reservoir up to 26.85 TMC. ^[2][14]

By this stage the dam structure, rehabilitation, roads, canals and downstream systems had their own timelines. That is why the Gandikota record includes several dates for different parts of the project. ^[2][5][14]

Current operating priority

Recent state outcome budgets continue to list faster movement of Srisailam water to Gandikota as a Kadapa irrigation priority. The focus is on moving water through the upstream system while it is available and then distributing it from Gandikota into the connected command. ^[15][16][17]