The Regional Board of Mayors learned Monday of a proposed Banks Lake Pumped Storage Project that could employ 2,500 people during construction and end up providing permanent employment for 150-200 workers.

Columbia Basin Hydropower managers told the mayors that the project could run as high as $1 billion and take several years to complete.

The target date for completion would be 2025, representatives stated.

But there’s a long way to go before anything could be declared “shovel ready.” The permit process and finding the money for the project are next on the agenda.

Grand Coulee Mayor Paul Townsend asked if the project would provide any tax revenues for the area. Tim Culbertson, secretary-manager, stated that if a private company provided the funding, then the project would be taxable.

The project would deliver water from Banks Lake through a 35-foot diameter penstock pipe to a pump-generating plant near Crescent Bay, then return the water through a second pipe to Banks Lake. In the process, the generating plant would produce some 1,000 megawatts of electricity to the power grid. It could generate at its maximum capacity of 1,000 MW for approximately 35 continuous hours, assuming a maximum five-foot drawdown of Banks Lake.

Grand Coulee City Clerk Carol Boyce said those pipes would go “right through our city.”

When asked if the pipes would be placed underground, Culbertson said it would depend on the costs.

The 30-foot-diameter pipe would start just south of the top of North Dam, some 40 feet underwater, and with gravity flow proceed some 900 feet to the pump generating plant. Then water from Lake Roosevelt would be returned to Banks Lake through the second pipe.

Culbertson said there would be need for the power because of early retirement of two large coal-fired power plants in the region due to environmental reasons and potential retirement of others in the future.

“You need some generation facility that can ramp up and down very quickly,” he told The Star later, adding that federal hydropower capacity is “pretty much fully tapped.”

He stated that California and Oregon have already decided to cut their environmental footprint by 50 percent in coming years by limiting the operation of gas-fired combustion turbines, and Culbertson added that Washington would likely follow.

Power generated would interconnect with either the Grand Coulee Dam 230 KV or 500 KV switchyards.

Columbia Basin Hydropower grew out of three irrigation districts in the Columbia Basin: East Columbia Basin Irrigation District, Quincy Columbia Basin Irrigation District and South Columbia Basin Irrigation District. Columbia Basin Hydropower currently owns seven projects, ranging in size from two to 94 MW, with total generation capacity of all projects about 150 MW. The power from five of the projects goes to the cities of Tacoma and Seattle. Two other projects are operated and maintained under contract with Grant County PUD.