New diversion dam is on the Army Corps' drawing table
April 30, 2009 · Updated 1:56 PM
By Dennis Box
The nearly 100-year-old White River diversion dam is moving closer toward being replaced by the U. S. Army Corps of Engineers.
Jeff Dillon, environmental coordinator for the Corps, said the project is in both the feasibility and design phase.
"We don't know the exact configuration and design right now," Dillon said. "But it would be a concrete and steel structure about 12 feet high with two gates to control the flow."
Puget Sound Energy constructed the diversion dam in 1911 when Lake Tapps and the White River Hydroelectric power plant operation were built.
Wood panels are used to control the flow and divert water into Lake Tapps and the Corps' fish trap.
The corps built the fish trap in 1942 during the completion of Mud Mountain Dam. Spawning salmon are trapped and transported by truck around the dam, which has no fish passages.
The wood panels on the diversion dam are often knocked down during high water and storms.
The panels were repaired in March after a storm in December and January knocked nine panels down.
The corps estimates a new diversion dam would cost about $17 million and would take about two years to complete. An estimate is the project would be started in 2008.
"We are going through a process of deciding what the fish and local folks need," Dillon said. "We and the federal interest in fish to be in sync with local interest. We need to make sure we have a barrier dam that works."
After meeting with Puget Sound Energy, Cascade Water Alliance, members of the Lake Tapps Task Force and government officials, a plan has been settled on for the federal government to fund the project.
The group considered another $3 to $4 million in improvements to the flume gate.
"We looked collectively at the entire gate structure," said Michael Gagliardo, general manager of Cascade. "We decided this stuff all works. It became clear the corps could do what it needed for the fish passage. So the corps will replace the existing dam. The corps obligation to the fish allows it to only pay for improvements for fish passage."
Cascade Water Alliance has purchased Lake Tapps, the flume and the hydroelectric plant, which was closed in January 2003, for an initial investment of $10 million.
If the Department of Ecology grants drinking water rights to the lake, Cascade will pay an additional $27 million. Cascade and PSE expect the final transfer of ownership to be completed in August.
According to Ecology spokesman Curt Hart, the drinking water rights for Lake Tapps are expected to be re-issued within the next few weeks,
The consumptive water rights for Lake Tapps were originally issued to PSE in June 2003.
The Puyallup and Muckleshoot tribes and the cities of Auburn, Pacific, Algona and Buckley, along with a private citizen, Robert Cook, appealed the issuance.
The appeal was upheld by the Pollution Control Hearings Board and remanded back to Ecology in August of 2004.
Dennis Box can be reached at firstname.lastname@example.org.