Sarsang Reservoir, Reservoir in Aghdara District, Azerbaijan

Sarsang Reservoir is a 13.85 km² lake on the Tartar River in Aghdara District, held back by a 125 m high and 555 m long dam that also carries a 50 MW hydroelectric station. Its rippled blue-grey surface splits into a wide main expanse and a narrower arm, with low earthen banks and a rounded dry peninsula on the right.

Built on the Tartar River in the Mardakert (now Aghdara) District, the reservoir began filling in 1965 and entered operation in 1976. Its 125-metre dam also carries a 50-megawatt hydroelectric plant. From the early 1990s until September 2023 it lay outside Azerbaijani control; on 15 October 2023 President Ilham Aliyev raised the Azerbaijani flag there. Reconstruction began in February 2026 at a cost of 16 million manats.

The reservoir's name comes from the Sarsang river and the village of the same name; the dam feeds the Sarsang hydroelectric station, which supplied 40 to 60 percent of the electricity of the self-proclaimed Nagorno-Karabakh Republic. In August 2013 the NKR proposed joint use of its irrigation water, and US OSCE Minsk Group co-chair James Warlick made a similar suggestion.

The reservoir lies in Aghdara District on the Tartar River, reached by the road opened in March 2025 from the reservoir to Umudlu village. The dam is 555 m long and 10.2 m wide, with the 50 MW Sarsang hydroelectric plant on it. Reconstruction of the reservoir began in February 2026 at a cost of 16 million manats, so access and conditions may change.

The dam wall is 125 m high and 555 m long, among the tallest in Azerbaijan. Its 50 MW hydroelectric station supplied roughly 40 to 60 percent of the electricity used in the self-proclaimed Nagorno-Karabakh Republic before 2023.