Bridgeport, WA — Workers are preparing to install a new 45-ton turbine at the second-largest hydropower producing dam in the United States, part of a multiyear upgrade that will generate power for an additional 30,000 Northwest homes.
The $120 million project at Chief Joseph Dam on the Columbia River is one of several planned around the country as the federal agencies that operate hydropower dams replace aging equipment and use new technology to produce more power from the same amount of water.
In the Northwest, about one-third of the region’s low-cost electricity comes from hydropower dams, many of which were built decades ago and require upgrades.
The region also is home to the largest power-producing dam in the country — Grand Coulee Dam — where work is wrapping up to replace 18 turbines. Ten new turbines are to be installed downstream at Chief Joseph Dam by 2014.
Chief Joseph Dam already supplies enough power for the city of Seattle. Between both dams, the new turbines will produce enough power for an additional 60,000 homes once they are fully operating.
These massive hydropower projects are key to integrating an increasing renewable energy supply, such as wind power, into the electric grid, said Mark Jones, manager of federal hydropower projects for the Bonneville Power Administration, the federal agency that sells electricity wholesale to public utilities in the region.
The frequent starts and stops of intermittent wind power can stress the electric grid, but hydropower can be dialed back to offset those stresses more easily than some other power sources, such as a nuclear or coal plant.
The 31 dams in the Columbia River system also offset carbon dioxide emissions equivalent to 20 coal plants, Jones said.
BPA is evaluating smaller projects that could improve reliability and efficiency in the power supply. Electricity ratepayers pay for all the projects.
“Most of what we spend money on is to just try to maintain the system for the next generation. By maintaining the aging infrastructure, investing in reliable upgrades, we continue to be able to produce reliable, low-cost power for the region,” Jones said. “And everywhere we can, we try to gain new efficiencies.”
Michael Garrity, Washington state conservation director for American Rivers, said upgrades such as these can help create flexibility in how other Columbia River dams are operated to better protect fish and wildlife and still meet regional water demands.
“That’s particularly true in areas where you know the dams are going to be around a long time and there’s no controversy about removing them. This certainly fits that case,” he said.
But Garrity said dam operators also should be moving toward a time when fish passage could be restored to the upper Columbia River.
There is no fish passage beyond Chief Joseph Dam. BPA has been working with area American Indian tribes to improve fish passage and habitat throughout the region. Construction of a new fish hatchery for the Colville Confederated Tribes is expected to begin in the coming months.