By Eric M. Johnson
OSO, Washington (Reuters) - Watching the now murky river from his kitchen window, Bill Best speaks in low tones of neighbors buried by a massive mudslide, where damage to salmon and steelhead trout spawning beds only adds to the grief in a rural Washington state community with deep ties to the land.
"The river's extremely important. We just thoroughly love this relatively natural, unspoiled river environment. It's why we are here," the 73-year-old avid fly fisherman said. "Hopefully in 20 to 30 years, it will be back to what it sort of used to be."
With the death toll from the March 22 mudslide at 36 and rising after millions of cubic yards of earth spliced with trees buried a neighborhood near Oso, the ecological damage to one of the nation's most storied steelhead fly fishing waters is already evident.
The roughly 45-mile (70-kilometer) north fork of the Stillaguamish River has been stained a dark gray-green by silt and nearly blocked by a mud dam, and a pumping system meant to aid search efforts is sending water mixed with sewage and chemicals back into the river.
Migrating salmonids, including federally protected Chinook salmon and steelhead trout, along with their eggs in the river's gravel beds and emerged smolt have surely been killed or will be damaged, state Department of Ecology spill responder Dick Walker said.
Soil samples won't be collected until search efforts end, but the amount of toxic chemicals leaking from households and cars crushed by the slide is relatively low compared to the volume of water, Walker said in an interview.
Yet silt, which suffocates spawning beds and harms fish gills as well as insect life, is likely to pile up down river in a Puget Sound estuary used in valley agriculture, and any increased water toxicity could possibly also harm shellfish production, scientists and an industry group say.
"It's going to have an effect on both the adults trying to swim upstream and small smolt salmon trying to swim downstream," Walker said, adding a monitoring station down river has already found damage to migrating smolts.
Between 1,200 and 1,600 Chinook return to the river each year, while steelhead number in the hundreds, said Bill Blake, co-chair of the Stillaguamish Watershed Council, adding it is too early to know the extent of damage to fish populations.
