News and Opinion from Sisters, Oregon
News and Opinion from Sisters, Oregon
Squaw Creek is on the move -- and it's not just water running downhill.
A November 28 flash flood washed out a private bridge on the creek and severely eroded the Highway 20 overpass in Sisters. The creek changed its course in several areas due to the flood event. In fact, the channel has moved as much as 100 feet and more in places, according to Bob Bridgeford of the Upper Deschutes Watershed Council.
According to Bridgeford, the November 28 flood registered flows of 1,800 cubic feet per second, the second-highest flow ever recorded on Squaw Creek.
The banks of Squaw Creek have eroded severely due to the increased flows. The creek water, carrying a heavy load of sediment down from the mountains, is carving a deep canyon through town.
According to Bridge- ford, variations in flow below the irrigation diversion at Three Creek Road make it impossible for anchoring vegetation to take hold and prevent erosion.
Bridgeford noted that the Squaw Creek Irrigation District is lining canals to help put more water back in the creek.
When the creek runs heavy, it carves through the bare areas, cutting deeper and deeper. Sometimes, the creek carves a whole new channel.
"Sisters itself is potentially imperiled by this behavior," Bridgeford said.
In response to the peril from possible flooding, the City of Sisters is considering changing its rules regarding building along the creek.
"It's still in the real preliminary stages," said city planner Neil Thompson. "We want to be more restrictive, widen the riparian protective zone."
Action on those changes is likely this summer, Thompson said.
Meanwhile, an inspector from the Division of State Lands noted that the washed-out bridge from November 28 can only be replaced by a much longer bridge -- otherwise it will likely just wash away again.
And, Bridgeford noted, the creek channel has moved away from the Pine Meadow Ranch irrigation diversion by more than 100 feet.
The Forest Service and the Upper Deschutes Watershed Council and others are exploring ways to fix the situation on the creek.
"Everyone knows the first fix is to have constant flow," Bridgeford said.
With constant flow through town, vegetation can be replanted and have a chance to establish itself.
Jim Cornelius is editor in chief of The Nugget and author of “Warriors of the Wildlands: True Tales of the Frontier Partisans.” A history buff, he explores frontier history across three centuries and several continents on his podcast, The Frontier Partisans. For more information visit www.frontierpartisans.com.
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