Long Lake Dam
Country	United States
Location	Lincoln / Stevens counties, Washington
Coordinates	47°50′14″N 117°50′23″W / 47.83722°N 117.83972°W / 47.83722; -117.83972
Opening date	1915
Dam and spillways
Type of dam	Concrete gravity
Height	213 ft (65 m)
Length	593 ft (181 m)
Reservoir
Creates	Long Lake
Total capacity	105,000 acre⋅ft (130,000,000 m3)
Power Station
Turbines	4x Francis
Installed capacity	71 MW

Long Lake Dam is a concrete gravity dam on the Spokane River, between Lincoln County and Stevens County about 30 miles (48 km) northwest of Spokane in eastern Washington. It forms Long Lake (Washington), a 23.5 mi (37.8 km) long reservoir, and has a hydroelectric generating capacity of 71 megawatts.^[1] The dam was built by Washington Water Power (now Avista Utilities), which operates five other dams along the Spokane.^[2]

Upon its completion in 1915, Long Lake Dam completely blocked salmon migrations to the upper portions of the Spokane River watershed, although much larger Grand Coulee Dam on the Columbia River extirpated salmon from the entire Spokane basin by 1942.^[3]

The Long Lake Hydroelectric Power Plant was also built in 1915. It was listed on the National Register of Historic Places in 1988. The listing included one contributing building and five contributing structures on 15 acres (6.1 ha) in Lincoln County, Washington and Stevens County, Washington.^[4]

It was built by the Washington Water Power Company^[5]

• List of dams in the Columbia River watershed
• Little Falls Hydroelectric Power Plant, also built by the Washington Water Power Co. on the Spokane River and NRHP-listed

• Historic American Engineering Record (HAER) documentation, filed under Ford, Stevens County, WA:
  • HAER No. WA-33, "Long Lake Hydroelectric Plant", 4 photos, 8 data pages, 1 photo caption page
  • HAER No. WA-33-A, "Long Lake Hydroelectric Plant, Spillway Dam", 16 photos, 6 data pages, 2 photo caption pages