Vamsadhara river basin occupies 8015 square kilometers in Odisha and the remaining 2815 km2 flows in Andhra Pradesh. The river basin receives high annual average rainfall of magnitude 1400 mm. The portion lying inRayagada district of Odisha is predominantly hilly and tribal populated area. Andhra Pradesh and Odisha roughly estimated that 115 thousand million cubic feet water is available for use in the river. They entered into agreements to use the available river water in 50:50 ratio. Andhra Pradesh has taken up Gotta barrage and Neredi barrage projects to put its share of water for use. However Odisha has not taken up new projects in the basin area to utilize its share of water. In fact it is diverting Vamsadhara river waters to adjacent Rushikulya river basin by constructing Harabhangi dam without taking prior consent from Andhra Pradesh. Also, Orissa has raised objections to Neredi barrage project on the grounds of land submergence in its territory during unprecedented floods. Approximately 25% of the available water in this basin is being utilized during the monsoon season by constructing barrages across the river. Reservoirs up to 100 Tmcftwater storage capacity are to be constructed for the non-monsoon period irrigation requirements, by which 100% water utilization can be achieved. Peculiar situation of this river is that most of the land to be irrigated is located in Andhra Pradesh while the possible storage reservoirs are located in Odisha. Vamsadhara River water disputes tribunal was constituted under Interstate River Water Disputes Act to resolve river water sharing issues between the two states. Justice Mukundakam Sharma is the chairman of Vamsadhara Water Dispute Tribunal. The tribunal pronounced its final verdict in September 2017 and permitted AP state to construct the side weir at Katragedda and Neradi barrage. The tribunal also upheld the sharing of 115 tmc ft total yield at Gotta barrage between AP and Odisha in 50:50 ratio as per the agreement reached between the states on 30 September 1962.
The Vamsadhara Project
Project was constructed on Vamsadhara river. Vamsadhara is the main river of North Eastern Andhra. The North EasternAndhra region consists of three North Eastern Coastal districts in Andhra Pradesh state in India. Vamsadhara project is designed to meet the irrigation needs of North Eastern Coastal Andhra. The Vamsadhara project has two canals viz., the left main canal, irrigating about, and the right main canal covering an ayacut of. The left main canal was completed long back. The right main canal was delayed due to various reasons. Gotta Reservoir feeds the right main canal. About 166 villages in seven mandals viz., L.N. Peta, Hiramandalam, Burja, Amadalavalasa, Gara, Sarubujjili and Srikakulam will be benefited from the RMC.
Lower Vamsadhara Project
The Lower Vamsadhara project envisages construction of 58m high & 1700m long dam across the vamsadhara river near Minajhola village in Rayagada district creating hydraulic head of nearly 62 meters. This project would be a multipurpose project serving power generation, irrigation and flood control.
Vamsadhara and Nagavali link canal
A 30 km long gravity canal is planned to link the Vamsadhara and Nagavali Rivers. It will run from Hiramandalam reservoir to Narayanapuram barrage near Amudalavalasa and bring an additional 50,000 acres of ayacut under irrigation using 10 Tmcft of water from Vamsadhara basin.