Generate Power And Protect Fish
We met Randy Stearnes, Community Relations Officer of Tacoma Power at Salt Water Park, (across the street from Powerhouse No. 2). Lodged in the gravel is an old 6 ½ ton Francis turbine from the Cushman Power House No. 2, complete with pockmarks or small holes. Stearnes explained that these are evidence of how much force the water had on the turbine - how much pressure it takes to move these and the force of collapsing water bubbles acting like bullets, creating the small holes. These holes, could affect efficiency, so in an active turbine, the holes are repaired. The turbines are used to turn the generators which produce electricity using magnetic fields. Stearnes said that in order for the generators to produce the right frequency of electricity, the turbines need to turn at 300 revolutions per minute, which is a little less than 900 cubic feet per second.
Tacoma Power owns and operates seven dams. Two in Mason County: Cushman No. 1(1925) on Lake Cushman and Cushman No. 2 (1930) on Lake Kokanee. Two on the Cowlitz River: Mayfield (1963) and Mossyrock (1968). Two on the Nisqually river: Alder Dam (1945) and LaGrande, original dam and powerhouse (1912) and dam and powerhouse addition (1945). They also own and operate one small flood control dam built in on the Wynoochee River (1973) and a Powerhouse (1993).
Across the street was the next stop of the tour - Cushman Powerhouse No. 2, the old concrete building with green trim and tall windows on Hwy 101, near Potlatch. Inside there was one of two new generators being built for the new Powerhouse, under construction at Cushman Dam No. 2, at the southwestern end of Lake Kokanee. Inside are the three working, original generators of the Powerhouse; the “Governor” – the old manual machine that was used to regulate the water flow. In the basement, Stearnes said most of the stuff is the same as it has been since the 1930’s. Upstairs has more modern touches with a new super computer that can be used to regulate water flow, taking the place of the “Governors” manual knobs and buttons. Though water flow can be regulated at each individual Dam, Tacoma Power usually regulates all their seven Dams from a central location in Tacoma.
Leaving Powerhouse No. 2, Stearnes hands out hard hats and said safety vests will be available up at the Dam.
At the Dam, we met up with Steve Fischer, one of the Assistant Generation Managers and Assistant Project Resident Engineer, Matt Wilson. Fischer moves us onto the crest of the dam and brings along pictures of an artist’s rendition to show us what the new “Fish Passage System” is going to look like and explains to us how it will work.
The juvenile fish will be caught in Lake Cushman with a ‘collector’ – a large floating fish collection facility. The caught fish will be shipped by truck to the top of Cushman No. 2 Dam and put in a transport hopper. This hopper moves on a tram which transports the fish down to the bottom of the dam, about 200 feet. The fish are then released into the North Fork of the Skokomish River to find their way to the Pacific Ocean.
The adult fish swimming up river will approach the fish pool at the same area the juveniles are released. The water will flow out and down, attracting the fish to swim up through the gates. The gates will close once a day and the fish will be crowded across the pool into the hopper. The hopper then transports the adults via the tram to the top of the dam to a fish handling facility, where the fish will be separated, counted, and marked if necessary to track them. They will then be transported past the upper Lake Cushman Dam to reach their final destination for spawning. When the coho return, the hopper could make up to18 runs a day on the tram.
The whole Dam Project cost is 27 and half million dollars with $18.8 million the cost of the Powerhouse and the rest for the Fish Passage System and other environmental costs. According to Fischer, those numbers were the original breakdown of the estimate and they are within $200,000 of closing on that original budget.
Tacoma Power received a $4.7 million grant from Department of Energy when they applied for an energy related Grant that also focused on how a company would be doing ‘good’ for the environment. After Tacoma Power described their Fish Passage System project and other environmental projects around the dam, they were able to receive the grant.
The other projects include two fish hatcheries, one on Lake Kokanee which will have coho, spring Chinook and steelhead; these will be raised to smolts and then will go directly into the North Fork of the Skokomish River. The other hatchery will be across from Powerhouse No. 2 on the Hood Canal and will raise sockeye. These will be released into Lake Cushman after a certain age, reared for a year, collected and released into the River, eventually to return as adults making their way back to the base of Cushman Dam No. 2. The two hatcheries are projected to cost about $10 million and will be designed by Tacoma Power, along with the Skokomish Tribe and Washington Department of Fish and Wildlife.
Fischer said most of his work lately involves fish, but of course, Tacoma Power is in the power business and the new generators are scheduled to be dropped into place on Nov. 13. The contractor has guaranteed the units will be ready for startup by January 1st followed by a full month of startup testing. If all goes well, the dam will be in commercial operation by early 2013.
Last November, Dale Hubbard visited Cushman No. 2 and reported on the beginnings of the project. We hope to continue the story on the whole Dam Project once the Fish Passage System is up and running and into the future with the two hatcheries.
Click on image below for Pictures of the Trip
All images by Jeff Slakey/2012
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