Private Pond May Have Contributed to Flood at Bottom of Rattlesnake Grade Last Week
BOGGAN'S OASIS, WA - A pond on private property a few miles up Rattlesnake Creek may have contributed to a large flow of water and debris that came down the bottom part of Rattlesnake Grade last week, causing significant damage and closing State Route 129 for several hours. Officials say the pond, which has been on the property for decades, is believed to have been expanded.
Following a heavy rainfall on the night of April 12th, trees, mud, water, and other debris made their way down to the Grand Ronde River near Boggan's Oasis. A small Washington Department of Fish and Wildlife bridge over Rattlesnake Creek was washed away as well. The bridge had been installed to create better fishing access.
A culvert that had been placed where the highway crosses the creek, approximately 1.39 miles upstream of the confluence with the Grande Ronde River, was also reportedly damaged. It had recently been installed to restore 8.97 miles of fish habitat.
Megan Stewart, District Programs & Operations Coordinator for the Asotin County Conservation District, surveyed the damage to fish and riparian areas the following day, including recent upgrades to improve steelhead populations. The creek is also home to resident trout and bull trout.
Rattlesnake Creek is a spawning location for steelhead and Stewart is sure the flooding and debris damaged the fish runs because it is spawning season. In addition, she says quite a bit of debris and mud went into the Grand Ronde River. There are numerous logs caught on islands downriver from the flood location, she says, adding that it is unknown at this time how much impact the flooding will have on fish populations in that river.
Meanwhile, the Washington State Department of Transportation still has the task of fixing SR 129.
"DOT already has a contractor that they are working with to get all the material along the road taken care of and removed, and then...also there's obviously some road damage too that needs to be repaired," Stewart says.
State and federal agencies will continue to work on making repairs to not only the highway and bridge, but the stream habitat and riparian areas.
"It will take us some time to come up with a plan for exactly what we should do," Stewart says. "Some of the vegetation will come back on its own. There's still some roots there and Cottonwoods seem to do fairly well with coming back."
Stewart says rehabilitating the damaged areas will be a lengthy process.
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