Berms, dikes, concrete blocks used to divert water, mud
By Ann McCreary
The Texas Creek home of Tom and Cheryl Race was a bustling work site last week as trucks delivered many loads of gravel, which a bulldozer operator contoured into a large dike upstream from the house to protect it from future flooding.
At the same time, a crew of eight Americorps volunteers shoveled away about 300 pounds of mud and debris deposited by flash floods that swept through the Race property after a thunderstorm on May 28.
“It’s been a pretty amazing two days. I feel like I’ve been in a whirlwind,” said Cheryl Race last Friday (June 12).
“It’s amazing how much can get done. You can’t put a price on what it’s like to have a community around you when you’re in need,” she said.
The Race home is one of a dozen at-risk residences within the Carlton Complex burn area where protective structures like berms, dikes and concrete blocks are being installed this month to divert mud and debris flow.
Flash floods are common in and around areas burned by wildfire, especially those as severe as last summer Carlton Complex Fire.
The floods at the end of May were a prime example. Heavy rains flowed down the bare, charred hillsides in the upper Texas Creek drainage, gathering mud, debris and power as the water swept downstream.
Unfortunately for the Races, the floods happened shortly before their flood diversion was scheduled to be installed.
The deluge inundated the Race property with several feet of debris, carrying off equipment, firewood and landscaping, and destroying underground irrigation systems. The house itself was slightly above the high water level and was not damaged.
In the wake of the flood, engineers assessed the damage and revised their plans for the Race property to provide more effective protection.
In addition to construction of the new dike, 60 concrete “ecology blocks” (made from recycled concrete) were installed upstream and along the front of the Races’ home. The blocks will provide a barrier if Texas Creek — normally a small stream flowing past the house — floods again after rainstorms.
Federal, state funding
The flood diversions are being constructed with $400,000 in funding from the federal Emergency Watershed Protection Program under the Natural Resources Conservation Service (NRCS). An additional $100,000 in funding is provided by the Washington State Conservation Commission.
The Okanogan Conservation District is coordinating the projects, which will be completed by the end of June, said Bob Clark, senior conservation planner for the district.
Work is being done by Allemandi Construction Inc. of Wenatchee and McMillan Construction of Loomis.
The projects includes homes up the French Creek, Texas Creek, Benson Creek and Finley Creek drainages, as well as a couple of homes along Highway 153 and a home near Pateros.
On one property on Benson Creek that was particularly hard hit by floods last summer, work involves not only building a dike but rechanneling water and constructing a bridge across the new channel, Clark said.
Each property involved a separately engineered design and all the work is being done at no cost to the property owners, Clark said. “The landowners participating are very grateful,” said Clark.
Not all homeowners who qualified for the flood protection program, however, chose to participate. Last August, engineers from the NRCS surveyed structures in the area burned by the Carlton Complex Fire and identified about 45 properties that could be protected by building dikes or other diversions.
All but the dozen receiving the installations this month declined to participate, many because they didn’t like the large size of the flood protection structures.
Participating property owners are required to leave the flood diversion structures in place for at least three years, when the most extreme danger of post-fire flooding will begin to diminish. If they want to remove the diversion structures after that, they must pay for the work themselves, Clark said.
In addition to these 12 landowners, the conservation district is continuing to assist about 300 landowners impacted by wildfires and floods, said Kirsten Cook, outreach and education coordinator for the conservation district.
District staff are working on deer and cattle fencing projects which provide cost-share funding to landowners and labor for fence building, using Washington Conservation Corps crews.
In March, more than 36,000 pounds of grass seed were applied to critical slopes on private land, said Cook.
Additional seed will be made available to the Okanogan County Noxious Weed Control Board to reseed areas treated for weed infestations, Cook said.
Additional support for Carlton Complex landowners will depend on funding from the state Legislature, which is currently debating the next biennial budget in Olympia.