Post Falls Dam accident injures worker and causes damage, but Avista says there’s no risk of dam failure

A construction worker was injured Tuesday morning when a crane flipped over and hit the Post Falls Dam.

The accident caused minor cosmetic damage at the site, but there is no risk of dam failure, said Avista spokesman Jared Webley.

In a news release, the utility company said it occurred in the North Channel Dam Spillway. The injured crane operator, who is employed by Slayden Constructors, a contractor working on the site, was taken to a hospital with non-life-threatening injuries.

“At this point, the crane failure does not appear to have caused any significant damage to the dam structure or impact on generation at the powerhouse,” Avista said in its news release.

Dam operators called the National Weather Service in Spokane to warn them of a potential dam failure that could cause a flash flood, which was precautionary, said meteorologist Miranda Cote. The watch was canceled not long after it was issued.

Ryan Bean, Avista’s plant manager for Post Falls Dam, said the incident occurred at approximately 9:15 a.m. when the 100-ton crane flipped upside down and its boom landed across the spillway, damaging the railings on top.

“Upon an immediate inspection by the operation staff and a subsequent follow up inspection with our dam safety personnel, it was determined there was no immediate threat to the dam,” Beans said. “The structure is stable.”

Bean said he did not know the cause of accident, but that it would be investigated.

Falls Park next to the dam is temporarily closed while they clean up the site.

Brian Harrison, a patrol lieutenant for Post Falls Police Department, said officers responded to the accident, and after consulting with Avista officials on scene, it was clear there was no concern of the dam failing.

“We knew pretty quickly there was no risk to the public,” Harrison said.

The police department regularly trains with other agencies to respond in case of an emergency dam failure. The most recent exercise was a couple of months ago, Harrison said. The department’s role would be to help notify the public and send officers to evacuate the areas downriver.

As part of the emergency response plan, there is a list of agencies Avista is supposed to contact in case of an accident, Harrison said, including the weather service.

Webley said he is not sure why the weather service put out the alert, but it was probably a miscommunication. He said Avista plans to sort out what happened.

Avista started a rehabilitation project of the North Channel Dam spillway this spring, with work expected to finish in spring 2027. The project will include rehabilitation of the dam’s concrete structure, replacement of nine steel spillway gates and gate hoists, and upgrades to the electrical and control systems. The work will also involve constructing a temporary retaining wall and dewatering the area upstream from the spillway.