SPOKANE, Wash. (AP) — A small earthen dam in Stevens County that was rated the worst in the state in 2016 had a slightly improved condition when it was re-inspected in 2021, according to an analysis released this week by The Associated Press.
The Van Stone Pit Lake Dam was the only high-hazard dam in the state listed in unsatisfactory condition and in need of immediate repairs, the worst category, when it was inspected in 2016, the analysis found. But it is now one of 50 high-hazard dams in the state listed in poor condition, the analysis found.
The state regulates about 1,100 dams, most privately owned.
The Van Stone Pit Lake Dam is on land that used to belong to a timber company. The land was foreclosed on sometime after 2016 by Stevens County officials for failure to pay taxes.
That 2016 inspection found overgrown vegetation on the earthen dam, holes in the downstream face; seepage on an embankment slope; inadequate spillway to handle heavy rains; and three homes in the probable flood inundation area. Not much has changed, except the dam’s rating was raised one notch after the 2021 inspection.
“Overall, the inspectors revealed that the dam is in poor condition,” the state Department of Ecology said last week. “Ecology recommends that the dam be removed.”
The agency does not think the dam is in imminent danger of failing.
Dating from the 1920s, the earthen dam is of unknown construction “because it was not built under Ecology’s permitting process,” the agency said.
“It is important to note that we do not own this dam, but will be providing assistance because it is in the best interest of the community,” Ecology said.
The dam, about 23 miles north of Colville, serves no purpose and was created when construction of a road berm impounded the water, documents said. It is 25 feet tall, about 100 feet long and about 15 feet wide.
Dams are categorized by the hazard they pose were they to fail. A high-hazard dam is likely to result in the loss of at least one human life if it were to fail.
Dams also are assessed by their conditions — ranging from satisfactory to fair to poor to unsatisfactory.
A dam in unsatisfactory condition has safety deficiencies requiring immediate action, but there are none of these in Washington. A dam in poor condition typically has safety deficiencies that may realistically occur, meaning repairs are necessary.
An Associated Press analysis tallied more than 2,200 high-hazard dams in poor or unsatisfactory condition across the U.S. — up substantially from a similar AP review conducted just three years ago. The actual number likely is higher, although it’s unclear because a couple states don’t track such data and many federal agencies refuse to release details about their dams’ conditions or the dangers they pose.
Many of the state’s giant hydro-power dams are owned by federal agencies or utilities.
There are a variety of reasons for the rising number of troubled dams. A heightened emphasis by some state regulators has turned up new concerns. Deferred maintenance has resulted in worsened conditions. Dams that were built decades ago now often pose more of a hazard than originally envisioned because homes, businesses and highways have cropped up below them.
A changing climate also plays a role. A warming atmosphere can bring stronger storms with heavier rainfall that can overwhelm older dams lacking adequately sized spillway outlets.
The $1 trillion infrastructure bill signed last year by President Joe Biden will provide about $3 billion for dam-related projects, but that’s just a fraction of what’s needed for safety upgrades and repairs to the thousands of dams across the country.
Of Washington’s 50 high-hazard dams listed in poor condition, the most are in Yakima County with seven.
Below are the state’s 50 poor condition dams, listed alphabetically by county:
Camano Island Cattle Co., Adams
Gap Road Reservoir, Benton
Paterson Ranch Reservoir, Benton
Blair Reservoir, Benton
Meadow Lake, Chelan
Colchuk Lake, Chelan
Square Lake, Chelan
Eightmile Lake Outlet, Chelan
Klonqua Lake, Chelan
Tri Mountain Estates, Clark
Haight Reservoir, Clark
Zirkle Partridge Ranch, Grant
Beacon Hill, Grays Harbor
Fairview Reservoir, Grays Harbor
Lords Lake East, Jefferson
Swano Lake, Grays Harbor
Sylvia Lake, Grays Harbor
College Hill, Grays Harbor
Newcastle Railroad Embankment, King
Lake Kittyprince, King
Upper Sunlight Lake, Kittitas
Johnson Creek Reservoir, Klickitat
Trask Lake, Mason
Belfair Wastewater Treated Water Pond, Mason
Indian Creek, Pacific
Slavic Lake, Pierce
Buck Mountain Reservoir No. 1, San Juan
Whistle Lake, Skagit
Kayak Lake, Snohomish
Rainbow Springs, Snohomish
Nielsen Dam B, Snohomish
Nielsen Dam C, Snohomish
Spokane Hutterian Brethren, Spokane
Fairfield Sewage Lagoon No. 1, Spokane
Newman Lake Flood Control, Spokane
Deer Park Sewage Treatment, Spokane
Ponderosa Lake, Stevens
Van Stone Pit Lake, Stevens
Den Hoed Dam No. 1, Yakima
Evans Konnowac, Yakima
Black Rock Orchards, Yakima
Parker Reservoir, Yakima
Evans Pond, Yakima
Roy Farm Irrigation Pond, Yakima