By Marcy Stamper
Melting snow and saturated soils in parts of the Methow Valley have spawned new streams, caused small mudslides, and washed out roads that became inundated when culverts became clogged with sediment and an unusually high volume of water.
One section of Rendezvous Road was so wet last week that a new culvert floated in the saturated ground and had to be weighed down with rocks and trees, according to Okanogan County engineer Josh Thomson.
There are minor problems around the county, but the most serious issues, resulting in the closure of a few primitive roads, are in the Methow Valley, primarily in areas that burned during the past two summers, said Thomson. “We’re still seeing increased runoff and sediment because of the fire,” he said.
While conditions have been changing daily as warm temperatures melt snow in some areas and dry out runoff in others, as of Tuesday (April 5), two primitive roads in the Methow Valley were closed to traffic.
Frost Road, about 3 miles west of town on Twisp River Road, was closed, as was the Twisp River side of Elbow Coulee Road, 2.5 miles further west. Elbow Coulee Road is open only at the north end, from the intersection with Patterson Lake Road to the Pine Forest turnoff.
There is considerable water on Elbow Coulee Road near the midpoint, according to Okanogan County Emergency Manager Maurice Goodall. “It will be closed until things dry up — there’s nothing we can do with it,” he said.
Frost Road problems
The most serious situation is at Frost Road, where county crews have been trying to keep the water to one side of the road so that the half-dozen residents can still get to their homes, said Thomson. The county maintains the road for about 1 mile.
“It was a big snow year after a burn. It’s the maximum runoff, with lots of sediment. Channels are filling up faster than we can clean them,” said Thomson.
Thomson said they have to wait until areas dry up to engineer a long-term solution. Trying to address problems in such wet conditions would only make things worse, he said.
On Frost Road, water was cascading down the hillside and had apparently ruptured an old concrete pipe that typically carries water along the shoulder. The privately owned pipe can usually handle the flow, but it is clogged with sediment and isn’t large enough for such a high runoff, said Thomson. Efforts by local residents to clear the pipe apparently caused more damage, he said.
The water on Frost Road was coming from higher up and not from that pipe, said Goodall.
The water crosses Frost Road at several spots and had flooded and carved a deep channel through a field along Twisp River Road. A good-sized culvert has been effectively carrying the water under Twisp River Road, said Thomson.
A dam at the lake near the end of the road owned by the Washington Department of Fish and Wildlife (variously called Frost Lake, Shaw Lake and Miles Lake) was allowing water to spill over as intended, according to Sherry Furnari, the Methow Wildlife Area Manager. Furnari checked the lake and dam three times last week and again on Monday (April 4). “It’s working as designed,” she said.
Water from the spillway goes into a ditch along the side of the road and down through a series of pipes and culverts, she said.
As in many parts of the valley, people said water was flowing down draws where they had not seen it for decades. A neighbor on Frost Road said this was the first time since 1996 that they had seen water coming over the spillway at the lake.
“The ground is sloughing and water is building up. Sometimes you just have to let things happen. The runoff if natural, but sometimes we have to channel it away from private property to keep people out of harm’s way,” said Goodall.
In the Upper Beaver Creek drainage, which burned two years ago, Storer Creek had overtopped its banks and was going across the road, said Thomson. County crews were monitoring Squaw Creek Road in the lower Methow Valley, which was reduced to one lane because of sloughing, said Thomson.
“It’s still several weeks until it tapers off, because the ground is so saturated,” said Thomson.
Once things dry up, the county will need to find a solution for Frost Road, but the situation is complicated by the fact that it is a particularly narrow right-of-way that will require permitting for a permanent fix, said Thomson.
Flooding in Twisp neighborhood
A problem at the Painter’s Addition neighborhood above Twisp, where water was flowing through streets and yards and threatening homes, appeared to be resolved this week. The problem was first reported on March 27, according to Andrew Denham, Twisp’s public works director.
Crews diverted the water with gravel and dirt to direct the stream away from a house to a vacant lot on May Street, where it was pooling and soaking into the ground without causing any damage.
The water appeared to be coming from the Lookout Mountain area and would usually go underground but, during this heavy runoff year, was remaining on the surface, said Denham.
Highway 153 slide
State Highway 153 was down to one lane just south of Black Canyon because of water over the roadway, with traffic controlled by a flagger, according to Wayne Rice, a maintenance supervisor with the Washington State Department of Transportation.
A citizen reported rock, mud and tree debris on the road at about 3:30 a.m. Sunday morning (April 3). A culvert in the bottom of the ravine had become plugged, said Rice.
Although the blockage is near mudslides that damaged and closed the highway after heavy rains in early March, it is not linked to the previous problems, which have been repaired and where a larger culvert is in place, said Rice.
The culvert causing the current problems is still plugged and crews have to wait until later this week (when the water is expected to subside) to dig it out, said Rice. “If we dig it out now, it will cave in and collect more sediment than we get out,” he said.
These problems are exacerbated in areas after a fire. “The problems are absolutely in burned areas. They’re still not re-vegetated,” said Rice.