Wanapum moves closer in turbine replacement

New machine to increase power, improve fish passage

WANAPUM DAM — Grant County residents may not notice any change in the way they get their power over the next decade, but officials at the Wanapum Dam want them to know that they are part of something big.

Dam officials are currently replacing one of the structure's 10 hydroelectric turbines, which is the first step in a plan to replace each of the turbines over the next decade. Crews from the Grant County Public Utility District and contractor Voith Siemens have been working long hours at the dam this week in an effort to get the new turbine's largest component, the turbine shaft, installed.

Brad Strickler is managing the turbine replacement project with Grant PUD, and he said the new turbine will increase the plant's generating capacity and improve fish passage at the dam once it is installed. Strickler said the turbine replacement project has been both interesting and a challenging undertaking. He said all the groups involved have done

well on the project so far.

"This is the largest project that has been undertaken by the PUD since the dams were built," Strickler said.

In an effort to allow people to see the project firsthand, Grant PUD will be holding tours of the new advanced turbine at the dam this weekend. The Wanapum Dam will be holding tours from 10 a.m. to 2 p.m. Saturday. Officials say to wear comfortable shoes, and adults need to bring photo identification.

The Wanapum Dam originally went on line in 1963 using the same turbine generators that it is using today. Wanapum was built to house 16 power generating turbines, and still has the capacity to hold those extra six turbines if they were ever needed.

The cost of the project is $15 million per turbine, for a grand total of approximately $150 million when the entire replacement project is complete. Strickler said all 10 turbines are on schedule to be replaced by 2012.

The new advanced turbine's design was funded by efforts of numerous utilities and the U.S. Department of Energy, and this turbine will be the first of its kind in the nation. The turbine weighs approximately 318 tons, with the turbine shaft accounting for the heaviest portion at about 80 tons by itself.

The turbine shaft itself also incorporates a new design. The 22-foot shaft was made in Romania, and first arrived at the dam in late October. The shaft's hub will be spherical, which PUD officials said eliminates gaps from the leading and trailing edges of the blades. The new hub is also designed to reduce shear and turbulence. The turbine will utilize six blades for generation, which is a one-blade increase from the existing unit.

Once it is up and running, the new turbine will increase the plant's generating capacity from 900 megawatts to 1,038 megawatts. Wanapum Journeyman Powerhouse Operator David Knannlein said the PUD will evaluate the new turbine for a year, and the horsepower should increase from 120,000 to 150,000.

"I think it's a phenomenal piece of engineering," Knannlein said.

Knannlein said the installation does reduce the dam's total capacity by one unit, but that it's not really an issue this time of year.

The dam does not run all of its units at once, according to he PUD, and the dam is very flexible in adjusting to the peaks and valleys of power use.

The turbine is scheduled to go on line in February, in time to test during the system for the spring juvenile salmon migration. The design is anticipated to make passage easier for fish and improve survival rates. The PUD hopes to achieve a 98 percent survival rate for fish passing through the dam with the installation of the new turbines and will begin testing this spring for fish survival rates.

Strickler said once the turbine is installed, the team will continue to proceed through assembly of the rest of the machine for the next eight weeks. He said the turbine replacement would be an ongoing process until they start commissioning tests in January.

Strickler said the new state-of-the-art turbine system is state-of-the-art, and he said the new turbine system is going to be the right thing for fish and for the dam. He added that the people of Grant County are part of something big with this new turbine system.

"It's a privilege for me to work on it," Strickler said.