Swan Lake North Pumped Storage Project P-13318

New License / Under Construction

Proposed Project Facilities

The Swan Lake North Project will consist of a new upper and lower reservoir, a high-pressure steel penstock connecting the upper reservoir with the powerhouse, a powerhouse with generating/pumping facilities, three low-pressure steel penstocks connecting the powerhouse to the lower reservoir, a transmission line, and substation, and access roads to the lower and upper reservoirs.

The asphalt, concrete, and geomembrane-lined upper reservoir will be created by a 7,972-foot-long, 58-foot-high earthen embankment and will have a surface area of 64.21 acres and a storage capacity of 2,568 acre-feet at a maximum surface elevation of 6,128 feet above mean sea level (msl). A bell-mouth intake fitted with a 38.6-foot-wide by 29.8-foot-long inclined screen and headgate will withdraw water from the upper reservoir and deliver it to the powerhouse through the 13.8-foot-diameter, 9,655-footlong, high-pressure steel penstock that will be predominantly above-ground with a 14-foot-long buried segment.

The powerhouse will partially be buried and will be constructed adjacent to the lower reservoir and contain three 131.1-MW variable speed reversible pump-turbine units for a total installed capacity of 393.3 MW. Upon entering the powerhouse, the steel penstock will trifurcate to distribute flow to each pump-turbine unit, with flow distribution controlled by a spherical valve located at the intake of the pump-turbine
units. The maximum hydraulic capacity of each turbine will be 3,230 cfs. Each turbine will discharge into the lower reservoir through a separate 9.8-foot-diameter, 1,430-footlong steel low-pressure penstock that will be predominantly aboveground with a 78-footlong
buried segment.

The asphalt, concrete, and geomembrane-lined lower reservoir will be created by a 8,003-foot-long, 65-foot-high earthen embankment and will have a surface area of 60.14 acres and a storage capacity of 2,581 acre-feet at a maximum surface elevation of 4,457 feet msl. Each reservoir will be fitted with a drainage system designed to detect, collect, and monitor water leakage from the reservoirs. A 500-foot-long, riprap lined trapezoidal spillway will be built into the crest of the upper and lower reservoir embankments at an elevation of approximately 6,135 feet msl and 4,464 feet msl, respectively.