Failed dams, other damage challenge several agencies
By Marcy Stamper
The Washington Department of Fish and Wildlife (WDFW) will repair the uppermost of five dams in the upper Benson Creek watershed as soon as weather permits.
All five lakes failed in an August 2014 rainstorm when logs and debris cascaded down from a hillside severely burned in the Carlton Complex Fire, damaging the spillways and sending a destructive deluge of water, mud and debris into the creek and Benson Creek Road and closing Highway 153.
WDFW owns the two lakes highest in the watershed — Chalfa Dam, the one it will repair, and an unnamed smaller lake that will be allowed to fill with silt and become a wetland, according to Chris Matson, an environmental engineer with WDFW. The three lower lakes are privately owned.
The repair of Chalfa Dam addresses safety concerns for property and infrastructure below the lakes, but other complex ecological, economic and infrastructure issues in the Benson Creek watershed are yet to be resolved.
Representatives from WDFW and the Okanogan Conservation District met with Benson Creek residents and irrigators two weeks ago to learn about WDFW’s plans and discuss other concerns in the watershed.
Because of the severe disruption of the ecosystem — including damage to the road, creek, irrigation pipe and private property — there are competing interests, according to Terri Williams, a conservation planner with the conservation district who chaired the meeting. Moreover, there isn’t enough information or money to address them all, she said.
“It’s an exceptionally complicated system in the first place, because there are so many interests, in water and ownership — and then there’s the land itself,” said Williams.
Carmen Andonaegui, a WDFW habitat program manager, summarized the issues for biologists, farmers and irrigators, and property owners: water storage and flood control, erosion and sediment, land values and property access, seasonal versus year-round flows in Benson Creek, and fish habitat.
The owner of the middle — and largest — lake, called Rabel Dam, made emergency repairs immediately after the breach, according to James DeMay, dam safety section manager for the Washington Department of Ecology. The other three lakes no longer hold water and there are currently no plans to restore them, he said.
The dams themselves didn’t fail, but logs and debris clogged the spillways and outlets, which eroded over time, emptying all five lakes within a day, said DeMay.
Ecology regulates the three larger dams and inspects them every five years. The other two are too small to be in the agency’s program, but the dam owners must inspect them annually.
Sediment has been accumulating more rapidly since the fire because area above the lakes burned so severely that there is little vegetation to hold the soil in place, and some soil actually repels water, said Williams. The upper Finley Canyon area around the lakes is among the most severely burned in the Carlton Complex Fire and scientists predict it will take a long time for the high slopes to recover, she said.
The U.S. Forest Service manages the area above the lakes, starting with the upper shoreline of Chalfa Dam. The agency has no plans to revegetate the area immediately around the lake, but will replant trees higher in the watershed this year or next, according to John Rohrer, range and wildlife program manager with the Methow Valley Ranger District. Virtually all the conifers burned, but some deciduous trees near the lake survived, he said.
The rancher who holds a grazing allotment in the area has also been working on obtaining funding for aerial seeding, said Rohrer.
Irrigation system destroyed
Despite long-standing obligations to provide water to a group of irrigators on Benson Creek, damage to the dams and pipes meant no water was used for irrigation in 2015, said Williams. In a typical year, by July or August, the creek is a mere trickle — sometimes completely dry — but since no water was diverted in 2015, Benson Creek flowed all summer, according to Jerome Thiel, a member of the water users’ association.
Possible fixes include switching irrigators to wells, instead of rebuilding the damaged pipe system, and putting water in trust to safeguard irrigation rights. Some residents want the creek run year-round, but others want the opportunity to work on their land when the creek is dry.
Reactions of property owners on Benson Creek taking stock of the impacts to their land and livelihoods range from acceptance to impatience.
Mark Raymond, who owns property on lower Benson Creek, was frustrated that the upper watershed seemed to have gotten priority. “How do you expect me to hang on? I’m losing real estate and potential value on my property since 2014,” he said. Raymond said he can’t access much of his land and has had to put a construction project on hold.
Others said not being able to irrigate last summer affected their livelihood and that their property had lost value from fire and flood damage.
Mike Sarratt said at least 2,000 cubic yards of sand had flushed onto his property. Higher in the watershed, that sediment is still piled 100 feet high and 1/4-mile long, he said.
Williams acknowledged the frustration of people all over the county whose property has been destroyed by fire or flood. “This is a natural disaster,” she said. “It’s beyond the ability of any one agency to address.”
The group is also studying the need for larger culverts to accommodate the higher flows predicted because of erosion. The rain that caused the destructive flood in 2014 was only a five-year event, said Williams.
“The potential for change is so great on Benson Creek. We have to think so carefully about what we do — one person’s culvert affects the next one down,” said Lynda Hofmann, a habitat biologist with WDFW.
The conservation district has asked the state for $8 million for design and planning for culverts in areas affected by wildfire. The funding has been included in the governor’s budget, but it is not known if the Legislature will fund it, said Williams.
The district received $1.5 million from the state last spring and completed “the easy work,” like fence repair and some restoration, said Williams. A more comprehensive request for some $12 million was not funded.
Despite the lack of consensus about what to do — and lack of money to do it — the group agreed to keep meeting, calling itself the Benson Creek Watershed Group. There was wide support for consulting a hydrologist and the conservation district will ask the Legislature for money to hire one.
“There are a multitude of different uses the water’s put to,” said Williams. “We have to balance all needs. It’s probably not going to be perfect, but we can try to make it fairly good.”