The Bonneville Power Administration is set to begin construction on a 500-kilovolt transmission line that will carry wind power from the Central Ferry Substation in Garfield County to the Lower Monumental Substation in Walla Walla County.
Approximately 2.5 miles of the 38-mile line will be built in the northwest corner of Garfield County, transferring renewable power from wind energy products like the soon-to-be-completed Lower Snake River Wind Energy Project.
The BPA received approval for the approximately $99 million project last month and is set to begin construction in the summer, BPA spokesman Michael Milstein said.
“Wind generation is the main driver,” he said. “It’ll carry about 840 megawatts (peak amount) of wind energy. It’s not all renewable (energy), but the majority will be wind. That’s where we’re really seeing the big growth in energy generation.”
Milstein said the system in that area of the state currently does not have enough capacity to handle the wind energy coming online.
“That section of the grid is kind of a bottleneck right now,” he said. “It’s like trying to put four lanes of traffic on a two-lane highway. We’re trying to expand that capacity. Some might be going to the Portland and Seattle areas, depending on where (the) producer has contracted to send that power.”
For the project to be approved, the BPA was required to meet National Environmental Policy Act requirements, which included several alternate routes for the transmission line and an environmental analysis. The area where the line will be built is rural and relatively undeveloped, Milstein said, and few environmental impacts were identified. In one area where the line crosses the Tucannon River, devices will be attached to the wire to prevent birds from running into it, he said. Some access roads will have to be upgraded.
The project is expected to create 170 jobs associated with construction, Milstein said.
“It’s an exciting project and it will both improve the capacity of the grid and provide some support for economic growth – jobs building the line itself and jobs through additional power projects that are feeding into it.”
The entire project consists of 161 new lattice steel transmission towers, which range in height from 104 to 189 feet. The approximate span between towers is 1,200 feet. The project is expected to be complete in about two years, in the summer of 2013.
“It’s definitely one of the larger projects we’ve undertaken in the last year,” Milstein said. “There aren’t many places where we’re adding to the grid, but this is a place that’s growing with wind power.”