Gibson Dam Hydroelectric (GDH) of Washington, US, is exploring the possibility of harnessing hydroelectric potential at the 60.6m high Gibson dam on the Sun river.

The dam, built by the US Bureau of Reclamation (USBR) in the 1920s, is a 293m long arch concrete structure capable of storing 122Mm3 of water for use by the Fort Shaw and Greenfields irrigation districts from May to October.

On 20 April the Federal Energy Regulatory Commission issued a three-year preliminary permit to GDH giving the company sole rights during the three-year period to determine whether it is economically feasible to build a hydroelectric power plant and to sell the electricity for a profit.

GDH is studying the feasibility of the project including the cost of building 32km of transmission lines and installing two turbines at the dam’s outlets. The study would also determine the cost of constructing a 15MW power plant with an annual energy production of 50GWh and would analyse the market for the power.

Power production would be limited to generation only when the irrigation districts draw the water.