The Calispell Powerhouse
The Calispell Powerhouse, originally known as the Dalkena Generating Station, is located on Calispell Creek, near Power Lake Dam. The plant was originally built in 1920 by the Dalkena Power Company for use by the town of Dalkena and its sawmill. Washington Water Power bought the facility in the late 1920’s and operated it until its purchase by the PUD in 1953.
The Powerhouse is a small hydro plant with a total capacity of less than 1 MW. The project originally consisted of Power Lake Dam, 3,900 feet of wooden flume, 600 feet of wooden penstock and the Powerhouse. In the 1930’s, the wooden penstock was replaced with 20” cast steel penstock. The Powerhouse contains 2, 250 kw Pelton wheel driven generators. The wooden penstock was replaced with a buried 30” concrete lined pipe in the 1950’s. The only outlet to Power Lake, other than the natural spillway, is through the flume and penstock.
Power Lake Dam
Power Lake Dam is located in southern Pend Oreille County, about 15 miles west of Newport. The lake is located on the North Fork of Calispell Creek, about three miles upstream of where it flows into Calispell Lake. The facility is owned and operated by the PUD. Water from the lake is used to produce hydroelectric power at the PUD’s Calispel Power Plant. Power Lake Dam is defined as non-jurisdictional by the Federal Energy Regulatory Commission under the Federal Power Act and are regulated by the Washington State Department of Ecology.
Power Lake Dam was constructed around 1920 by the Calispel Light and Power Company. In 1953, the dam was sold to the PUD. The concrete-encased steel penstock, connecting the dam to the powerhouse, was originally a wooden flume. This was removed and replaced by a 30-inch pipeline in the 1950’s.
In 1995, the dam was raised to prevent overtopping during the design flood event. The increase in dam height was accomplished via construction of a concrete parapet wall at the crest of the rockfill dam. The parapet wall raised the dam crest by about 7 feet to elevation 2416.0 feet. This increased the spillway capacity to 10,520 cfs. An additional goal of the facility upgrade was protection of the toe of the dam from erosion during high spillway flows. This was accomplished by placing a shotcrete facing over the toe of the dam and left side of the spillway channel.
Power Lake is a 62 acre reservoir impounded behind the 50 foot high Power Lake Dam on Calispell Creek. The lake has a normal storage volume of 800 acre-feet at the spillway crest elevation of 2403.0 feet, and a maximum storage of 1686 acre-feet at the dam crest elevation of 2416.0 feet.