  |
|
|
Department of Ecology News Release - March 13, 2003
03-039
SPOKANE - A plan to reduce harmful "total dissolved gas" in the Lower Snake River will be discussed at a meeting and public hearing on the evening of March 25 in Kennewick.
The Washington Department of Ecology (Ecology) is seeking public comment on the proposed cleanup plan, or total maximum daily load (TMDL), as it is sometimes called. The cleanup and accompanying implementation plan, when completed, will be submitted to the U.S. Environmental Protection Agency for approval.
A brief presentation followed by a formal public hearing will begin at 6:30 p.m. Tuesday, March 25, at Ecology's office at 315 W. 4th Ave. An informative question-and-answer session will follow the hearing.
The cleanup plan identifies ways to reduce total dissolved gas in the Lower Snake River - from the Idaho border to its confluence with the Columbia River
The "total dissolved gas" is simply air. In this case, most of the problem is from nitrogen. When water spills from the top of the dam, the high pressure mixes the air into the water. Fish living in "gassed-up" water can get "gas bubble trauma," much like scuba divers get the "bends."
Saturating the water with dissolved gases or air may result from either natural or human-caused conditions. The primary source of elevated dissolved gas in the Snake River is the water that spills from federal dams - Ice Harbor, Lower Monumental, Little Goose and Lower Granite.
Spills result when river flows exceed the capacity of the dam's powerhouse. Sometimes spills are caused on purpose to assist fish passage. The Snake River's salmon populations have declined significantly, and inadequate fish passage has been identified as one of the causes.
"It's been a real balancing act for resource managers," said Megan White, who manages Ecology's water-quality program. "Total dissolved gas is harmful to fish, and yet we need to flush more water through the dams to help fish pass through them safely. We're trying to balance both those factors - fish-passage needs with fish-breathing needs."
The public comment period on the plan will end April 4. To review the plan on the Web and get more information, go to http://www.ecy.wa.gov/biblio/0203004.html
###
Media Contact: Jani Gilbert, public information, 509-329-3495; pager, 509-622-1289.
Copyright © Washington State Department of Ecology. See http://www.ecy.wa.gov/copyright.html.
