photo credit: Russian River Parks & Recreation District
The Vacation Beach seasonal dam, undamaged in this photo, sits
downstream from Guerneville.

A seasonal dam on the Russian River has failed, prompting road and beach closures ahead of the Labor Day holiday weekend.

Sonoma County Supervisor Lynda Hopkins, who represents West Sonoma County, said the Vacation Beach Seasonal Dam, downriver of Guerneville, appears to have failed in evening on August 29.

"One of the sort of steel elements in the sort of summer dam for Vacation Beach, which is installed annually by the Russian River Rec and Park District failed," Hopkins said.

"So there was a very, very sort of forceful jet of water, kind of a wave of water that went through and unfortunately it caused damage to the county road," Hopkins said.

Hopkins noted that drivers in the Vacation Beach area will most likely have to add extra minutes to their car trips going forward.

"We actually now have a hard closure at the Vacation Beach summer crossing and road," Hopkins said. "Because the road is unstable and unsafe at this point in time."

Hopkins said there's been no major issues reported downstream of the burst dam, but she does advise dock owners downstream watch for flow changes.

Hopkins said the damage to the seasonal dam was "pretty dramatic."

"So it's going to show quite a bit of erosion," Hopkins said. "We actually had the CHP helicopter come over from Napa and fly over the river and they could see that there had been kind of a water surge that went really down the river below Vacation Beach, very clear, you know, in the Monte Rio area before going out to the ocean."

Hopkins said her goal in the long-term is a permanent crossing, but said for now, "we are hopeful that before next season we will be able to reinstall, fix up the road and get the summer bridge in."

Hopkins said while some planks from the damaged structure have been removed by the Russian River Parks and Recreation District, which maintains the seasonal dam, she said they don't plan to remove it until after the Labor Day holiday weekend.