Operation start: 1949

Power house: underground

Altitude above the sea level: 1,856 m

Pressure (h) 45 m

Installed/ available capacity: 34.24 MW / 25.24 MW

Turbines: 2 x 16.96 MW + 1 x 0.32 MW

Average annual production: 21.2 GWh

Open diversion canals: 2,000 m

Diversion tunnels: 5,797.72 m

Operation regime: Irrigation seasons


The Sevan HPP is the first stage of the Sevan-Hrazdan Cascade implementing water intake from Lake Sevan. It includes:

  • shore intake structure equipped with the fish protection system, intake channel,
  • water intake of the second stage, which directly takes water for the plant,
  • underground penstock,
  • underground plant structure,
  • tailrace channel,
  • switchyard,
  • ground control building.

The shore intake structure, equipped with the fish protection system is a water intake device with three openings, three fish accumulating tunnels which are connected with the fish accumulator tank, which, in its turn, is connected to the spill tunnel of fries. The shore intake structure provides the water releases from Lake Sevan to the HPP and the spill of fries back to the lake without injuring them. This has a significant environmental importance for Lake Sevan.

The HPP’s underground building is located on the depth of 100,0 m and consists of two blocks, i. e. turbine and water-discharge. Two needle gates are located in the water-discharge block, providing the intake of the necessary quantity of water through the Hydro Plant in case of emergency shutdown. Two units with radial and axial turbines are located in the building. The project capacity of each unit makes 17,0 MW, but because of the decrease of the Sevan Lake water level by 15,0 m the available capacity of each hydro unit makes 12,0 MW. There is also a small hydro unit (320 kW) in the building of the plant, which provides the Sevan HPP's restoration during the system's shutdown.

The diversion is of mixed type: the length of a feeding channel is 2,000 m, the length of the diversion pressure tunnel is 283.5 m, the length of the drainage tunnel is 5,514.22 m. The diversion capacity is 70 cubic meters per second. The estimated consumption makes 31.5 cubic meters per second, the idle flow rate makes 5 cubic meters per second.