‘Like an avalanche’: Landslide creates large wave in Lake Roosevelt that damages docks

Earthen cliffs directly west of Colville Flats Beach gave way this weekend, causing a sizable wave in Lake Roosevelt that damaged several area docks downstream from Kettle Falls.

Eric Weatherman, 62, is the owner of Columbia Navigation, a tug boat and barge contractor that works to remove floating debris from the lake under contract with the U.S. Bureau of Reclamation. He boated out Monday to survey the damage.

He called it one of the largest slides he’s seen in his family’s 55 years of working Lake Roosevelt.

“It looks like a wall of water went up into the trees,” Weatherman said. “As the water returned back, it took out tons of and tons of trees and vegetation. Actually, it looked almost like an avalanche. All the debris was on the back side of the trees, which is a thing that big waves do.”

Even the water depth changed along the shoreline, he said.

“When we pulled up in our boat, areas in front of the slide that had been 3 to 5 -feet deep are now 10 to 15 -feet deep,” he said. “It displaced the river bottom, as well as the standing bank.”

Weatherman navigated the floating debris field and issued a warning to boaters to avoid the area.

“I’m going to say (the shore) lost 150 feet” back from the shoreline, he said. “There were trees on all of that area. All of that timber is in different states. Some of it’s buried, some is jammed into the bottom. Some of those were 70-foot trees and now only 15 feet are sticking out of the water.”

Weatherman said it appears the slide caused a massive wave from north to south as the land gave way. It then surged east toward Colville Flats Beach.

“Colville Flats was completely covered in water, and I think it took 10 years of accumulated debris there and refloated it,” he said. “The debris is everything from softball-sized to 70-foot trees and root balls.”

Lake Roosevelt was formed by damming the Columbia River at Grand Coulee Dam in 1942. Since then, the changing water depths have caused several areas of earth, sometimes referred to as chalk bluffs, to slough off.

Weatherman said it was the largest such event he could remember.

“I’ve seen two or three others, but not this big in terms of cubic yardage,” he said. “I’ve never seen a slide this tall. I’m going to say it was nearly 200-feet tall.”

Staci Lehman, spokeswoman for the Washington state Department of Fish and Wildlife, said the wave hit strong enough to dislodge a dock at Sherman Creek Hatchery, which is north of the slide. The wave sent a dock and several fish pens full of triploid rainbow trout for a ride.

Sherman Creek Hatchery is located on the west side of Lake Roosevelt, the same side as the slide. It’s also located up a creek from a bay, meaning that the wave had to have come inland some way before it caused the damage.

“We are not positive when it happened,” Lehman said. “One of our employees went to check on the net pens on Sunday morning. They saw that the dock had floated away.”

Crews jumped in a barge and went looking for the dock, which was quickly located down river from the hatchery.

“They brought it back. It’s now hooked to another dock in a temporary configuration,” she said. “The fish were all fine.”

Other state crews had filled the pens with the trout on Thursday. Triploid trout are bred specifically so that they cannot reproduce. Mostly, the trout provide a steady source of fish for anglers.

“Those pens would have been next year’s release, for spring of 2025, into Lake Roosevelt,” Lehman said.

She was not sure of how much it will cost to re-attach the dock and the fish pens back at the hatchery in a more permanent fashion.

Several lake residents posted on Facebook, including one photo that claims to have caught a 30-foot wave streaming away from the slide.

The Rickey Point Sail Club posted a picture Monday of something floating out in the water, under the caption: “Our dock.”

The sail club is located on the east side of Lake Roosevelt, directly across from where the slide took place.

On the club’s page, Becky Esvelt responded: “I think we need a new dock.” Earlier, Esvelt posted another photo showing the damage. “Good thing the boats were all out when the wave hit!”

Efforts to reach Esvelt and the sail club were not immediately successful on Monday.

Dispatchers from both the Ferry County and Stevens County sheriff’s offices said they did not receive any calls about the landslide or wave and had not heard of any reports of damage.

Lehman said state crews were still checking the area. She believes the slide was in an area of several undeveloped camping areas, but she was not sure.

“Apparently, where the land sheared off was near a wildlife area that DFW manages,” she said. “We are looking into it.”