Flash flood watch in place for Libby as water released from damaged dam

Engineers on Sunday decided to implement a controlled release of water from the Lower Flower Creek diversion dam above Libby to reduce pressure on the damaged structure as more rain hits the region this week.

A low spot on the earthen embankment was breached for roughly 12 hours during a flood event Dec. 11, resulting in moderate damage to the dam. There are no concerns with the larger Flower Creek Dam upstream.

“Forecast rainfall has the potential to cause additional damage to the [lower diversion dam], bringing the risk for uncontrolled water released into the town of Libby,” the National Weather Service stated in issuing a flash flood watch for Libby.

The watch is in place through Wednesday afternoon.

The Lincoln County Sheriff’s Office said the controlled release of water “is a risk mitigation operation, not an emergency response.”

The release was expected to last three days and be less than peak flows experienced during flooding. However, residents in nearby areas are advised to pay attention to changing stream conditions.

Another potent atmospheric river is expected to douse the region with more heavy rain through Wednesday.

Snow levels are anticipated to start around 7,000 feet Monday before falling to valley floors behind a cold front early Wednesday. Forecasts suggest 0.75 to 1.25 inches for the valleys of Lincoln, Mineral, Sanders and Flathead counties. Up to 3 inches could fall in the mountains.

“A high-end scenario could bring a total of 4 inches to the Cabinet and Purcell mountains,” the Weather Service warned in its Monday forecast.

The Fisher River near Libby was projected to crest at 6.33 feet on Wednesday, below the 7-foot flood stage.

Due to saturated ground, additional rainfall brings the risk of rock and landslides across the area.

During last week’s flood, a massive landslide destroyed a garage in the Eagle View Lane area of Sanders County. Several bridges and roads were washed out across the region, including the Granite Creek Bridge on Big Cherry Creek and the Keeler Creek Bridge near Libby. A bridge crossing Prospect Creek was washed out in Sanders County.

With more rain and high winds in the forecast this week, Lincoln County Sheriff Darren Short and other officials are urging residents to remain aware and take precautions to avoid the dangers that currently exist.

Alerts will be issued through the CodeRED system and the Lincoln County Health Department’s Facebook page. CodeRED allows emergency personnel to contact residents with up-to-date alerts via email, text message, voice calls or mobile app notifications.

A cyberattack in November affected the service, but it is operating again after work by county Emergency Management Agency Director Boyd White. For those who signed up before March 31, 2025, no action is needed. Those who registered after that date need to register again.

To sign up, visit accountportal.onsolve.net/lcema.

Another place for information is the county’s Emergency Operations Center. People can call 406-293-6295 for updates.

Short said residents should avoid driving on roads that may have been affected by floodwaters. Short himself had an experience where he drove up a road to install “road closed” signs, but upon his return he noticed a section of road where the soil had washed out underneath the pavement.

“That’s why I strongly urge people to be very careful where they are traveling on roads we’ve identified as affected. There are also Forest Service roads that are washed out, and we expect to see more,” Short said.

Jesse Haag, the county planner and local floodplain administrator, also shared a story of how quickly conditions have changed.

“We were at the Keeler Bridge assessing it, and before we left, it blew out and we had to take another way out,” Haag said. “The streams have dropped, but we’re not sure how the rain will affect things. It’s not the time to put our guard down yet.”

A Type 3 Incident Management Team was expected to arrive in Libby on Monday to assist with response efforts.

    A rock and mudslide damaged a garage on Eagle View Lane in Sanders County on Dec. 11, 2025. (Tracy Scott/Valley Press)