Black Rock reservoir deemed too costly

YAKIMA – The U.S. Bureau of Reclamation says a massive reservoir proposed to improve water supplies in central Washington’s drought-prone Yakima Valley would be too costly, a decision that potentially ends years of studies that have already cost $18 million.

A final environmental impact statement released Friday evaluated the potential for the Black Rock reservoir, as well as two other projects that could provide more water for irrigators and municipalities and improve stream flows for fish.

But the bureau determined that all three projects would be too expensive and fail to meet all of the criteria necessary for major federal water resource projects, said Gerald Kelso, manager of the bureau’s Upper Columbia Area Office in Yakima.

The bureau recommends against pursuing any of the three alternatives, but says efforts will continue to improve water availability in the region.

“We are committed to working in collaboration with others to look for long-range solutions to future water supply needs in the Yakima basin,” Kelso said in a statement.

The Yakima Valley is home to thousands of acres of hops, wine grapes, tree fruit and other crops, but many irrigators face water shortages during periods of extreme drought.

State and federal officials have been researching additional water storage in the basin – and the Columbia River basin, as well – in hopes of alleviating water rationing for irrigators during dry years, improving stream flows for threatened and endangered fish and providing water to meet demand from growing communities.

As proposed, the Black Rock project would have drawn water from the Columbia River to a 1.6 million acre-foot reservoir behind Priest Rapids Dam.

An acre-foot is the amount of water needed to cover 1 acre 1 foot deep, or about 325,850 gallons.

The project’s cost was estimated at about $5.69 billion, but potentially as high as $7.7 billion. The impact statement also showed Black Rock would return just 13 cents for every dollar spent to build and operate it, down from 16 cents earlier this year.

The high cost wasn’t the project’s only flaw.

Another report, released in January, revealed that the reservoir could seep so much it would significantly raise the water table at the neighboring Hanford nuclear reservation, increasing the risk of spreading radioactive and toxic contaminants to the Columbia River.

Longtime supporters of the proposal, who paid $18,000 in recent months in radio and TV commercials promoting it, said the economic analysis failed to consider significant recreational benefits and understated benefits to fish recovery. They also said efforts could be made to mitigate any seepage toward the Hanford nuclear site.

The impact statement included mitigation proposals, but they weren’t enough to overcome the project’s other downfalls.

The conservation group American Rivers said it supports efforts to explore less expensive and less environmentally risky alternatives to Black Rock.

Former congressman Sid Morrison, chairman of Black Rock proponent group Yakima Basin Storage Alliance, said the report released Friday still shows the project is technically feasible.

He also said supporters likely will push for federal legislation to get the project built.

“Since their guidelines were changed 40 years ago, the bureau has never approved a project, yet a whole lot of things have been built,” he said. “What the agency uses for their guidelines isn’t adequate to measure what people want as we get into the 21st century.”

The bureau also found two other proposals didn’t meet criteria adequately and were not economically justified.

Wymer Dam, about 15 miles north of Yakima in the Lmuma Creek Canyon, would have resulted in a reservoir that held 175,000 acre-feet of water. The third proposal included Wymer Dam plus an additional system to pump water.