the film forum library tutorial contact

Columbia, Snake Dams Scrutinized by Mike Lee, Herald staff writer Tri-City Herald, November 17, 2002

Agencies hope to work within hydropower system to improve water quality

The Columbia-Snake hydropower system is under scrutiny this fall for its role in elevating river temperatures and adding dissolved gases to two of the Northwest's largest rivers.

But even Environmental Protection Agency officials say they are not angling for lower Snake River dam removal as a possible solution to pollution problems that can harm federally protected salmon.

"This is not about taking down dams in any way," said Mary Lou Soscia, Columbia River coordinator for the EPA in Portland.

Instead, agencies are aiming to work within the existing system to upgrade water quality.

The two massive federal-state-tribal studies on temperature and gas problems will look at fixes, some of which are expected to be proposed in a document due out in December.

"Solutions are going to be in the implementation strategy, and we are still working on that," said Jani Gilbert, spokeswoman for the state Department of Ecology. "We want to work with dam operators to improve performance and move toward meeting the ... goals."

It's hard to gauge the potential impact of the studies on the Columbia-Snake hydropower system. However, similar total maximum daily load (TMDL) studies on the Yakima River have forced substantial water quality upgrades in recent years.

Unlike the Yakima River, the big questions on the Columbia-Snake system center on the roles of dams that provide enormous amounts of power for the region.

One preliminary report squarely blames the dams for raising water temperatures above state water quality criteria in the summer, something many river watchers have taken for granted and the topic of a suit environmentalists brought against the Corps of Engineers a few years ago.

Pre-dam temperatures also could get quite warm, according to the preliminary document, but elevated temperatures are much more frequent with the dams.

"The dams appear to be the major cause of warming," it said. "Free-flowing river water temperatures cooled more quickly in the late summer and fall."

Likewise, documents about dissolved gases implicated dams for mixing atmospheric gases with water below the spillways. The catch there, however, is that water often is spilled to help fish past dams, forcing managing agencies into a delicate balancing act.

"Part of the problem is that the river is very complicated and very complex," Soscia said.

Rick Parkin, temperature study leader for EPA in Seattle, said the temperature plan would be the more difficult of the two to address.

"(Studies) might show that we just can't make the river any cooler or as cool as the TMDL calls for," he said. "There is not a whole lot that probably can be done."

If so, the federal water quality standard might be amended to accommodate best efforts, Parkin said.

The Corps of Engineers and the Bonneville Power Administration already try to cool the lower Snake by releasing cold water from Idaho's Dworshak reservoir each summer. Soscia said Dworshak releases might be adjusted to provide additional cooling.

"We are really interested in using that as a model," Soscia said.

The Corps also has made dam upgrades to lessen the amount of dissolved gases in the river, making that the less sticky of the two problems. "They have a pretty good idea of what can be done to control gases, and they are well on their way to putting those in place," Parkin said.