On Thursday night, Dec. 11, Montesano area residents came out to hear the current status of the Lake Sylvia Dam from representatives with the city of Montesano, Grays Harbor Emergency Management, and Washington State Parks.

The deluge of rain over the of past couple days caused increased stress on the aging dam. The dam is located within Lake Sylvia Park and is managed by Washington State Parks.

Montesano Mayor Tyler Trimble opened the town hall by welcoming everyone and acknowledged hosting the meeting on such short notice.

“As we were in a planning meeting, it came to our attention that we should probably have a town hall and at least get some information so people understand what is actually going on so it doesn’t look like we’re falling behind the eight ball somewhere,” he said, adding that “it’s important for you to hear clear and concise and accurate information.”

Discussions and planning to mitigate the possible effects of the atmospheric river began a week ago with the city and Emergency Management and continued into this week.

“Tonight, we want to continue the conversations and expand from our state partners and into the community so that you all know what is going on,” Trimble said.

Miles Wenzel, the Southwest Region manager with Washington State Parks, provided an overview of the management of the dam and that an emergency action plan was written several years ago.

“Recently, more studies were done, more observations were done of the condition of the dam,” Wenzel said. “A lot of information came back roughly a year ago that had specific information on the condition of the dam.”

Because cracks were observed earlier this year, Washington State Parks worked with the Department of Ecology Dam Safety Office to update the emergency action plan. Additionally, electronic lake monitoring was installed, along with visual lake monitoring.

“This updated plan is more robust in what our actions are and at what lake level things are happening at,” said Wenzel.

The four to five inches of rain that fell on Monday caused a lot of large woody debris to be pushed into the spillways. This resulted in the lake rising roughly one foot an hour and triggering the alert to raise from Level 1 to Level 3 in quick succession.

Wenzel said that “what that means visually when you’re out of the park. you walk over the train trestle, you see that little concrete curbing and you see the grass field down to Sylvia Creek. Water was flowing over that concrete curbing, which is our emergency spillway.”

On Tuesday State Park crews and Montesano Public Works removed the debris from the spillway and the lake.

“And as soon as we did that work, we really saw significant lowering of the lake,” said Wenzel. “It was very impressive to see all these different people coming together.”

He concluded by saying that as of Thursday, the lake level was below the 102-foot mark, which is emergency Level 2.

“We are going to stay in that emergency Level 2 through the weekend because we do have another weather system coming in next week for the next five days,” Wenzel said. “So I just want to reiterate from my perspective, I couldn’t think of a better team to work with.”

Hannah Cleverly, deputy director of Emergency Management for Grays Harbor County, discussed the actions Emergency Management took on Monday once the lake level began rising.

“On Monday evening, upon notification, I started making phone calls to the city of Montesano and their representatives, and additionally to the sheriff of Grays Harbor County. … We made a decision that we were going to come into the Emergency Operations Center, which is located right up here on Spruce in the Forestry Building.”

When emergency level 3 was reached, early Tuesday morning a notification via the Grays Harbor emergency alert system was sent to residents in the area identified as possibly at risk.

Later on Tuesday, Emergency Management was activated to their full notification and the city of Montesano declared an emergency; the county declared an emergency on Wednesday.

“From there, we have continued to show up in the Emergency Operations Center. We have continued to monitor the lake levels,” Cleverly said. “And throughout this week and throughout our planning meetings, we have also additionally been working toward a plan for worst-case scenario.”

Both Montesano Fire Chief Dave Busz and Police Chief Robert Wilson shared how their respective departments have played a role in the situation, expanding a bit about what they shared at Tuesday’s Montesano City Council meeting.

“On the emergency side, I’m responsible for rescue and response after the event so we work with an end goal, we come backwards to what our solutions are going to be,” Chief Busz said. “We had kind of a broad stroke plan and then we had targeted-like surgical solutions. We knew we had an inundation map and a specific set of addresses and parcels that we wanted to target because we know who lives there because we mapped that out through our pre-planning process.”

Busz assured the audience “in the event that we have a complete damn failure, not that it will happen — but we want to prepare for the worst, hope for the best — we have a very surgical and targeted solution.”

In his remarks, Police Chief Bob Wilson said, “It’s been a long 72 hours, but I think we’ve done a lot of good work done in the right way to ensure public safety.”

He directed the audience to the inundation map on the wall, which displays the worst-case scenario should the dam rupture and fail.

“The best way to describe where that inundation zone will end up is if you’re heading out on West Pioneer and you’re heading toward the cemetery, there’s a little bridge that you’re going to go back to, and that is Sylvia Creek so that is where the water is going to accumulate in a worst case scenario,” Chief Wilson said. “And as you can see, there’s already some flooding going on there. That’s not because of the dam failing. It’s just our standard, a lot of water, but a short amount of time.”

Wenzel returned to the podium to provide an update on the situation going forward. Because there is another weather system arriving on Monday, “we’re actually going to keep the park closed through the weekend in preparation for next week’s weather event,” he said.

He added that the landslide at the park’s entrance has been partially cleared so emergency crews could access the park, but the hillside isn’t stable and it needs to dry out before crews can stabilize it.

“In the meantime, Parks staff has learned a lot about how this lake responds to weather. They’ve learned a lot about how much rain fills the lake,” Wenzel said. “We didn’t have that data before this year. … And we’re hoping with the data that we’ve collected that that’s going to help us tell a story and help us manage this lake level moving forward.”

A Q&A followed, and was short, with audience members asking about the opening of the gates, to which Wenzel said that all the gates had been open for months in preparation for a storm and that all five gates have since been removed. To the question of whether the Jan. 1 First Day hike would go as scheduled, the response was stay tuned for information.

When asked about the dam’s current state, Wenzel explained that there are crack monitoring systems installed on the dam that are inspected by both a private contractor and the Ecology Dam Safety Office. This week no movement was observed on the dam.

“There’s still more studies to be done, but the good news was, as far as testing or seeing what actually happens at 104 feet, this is the first time it’s ever been verified that the dam didn’t move at a Level 3 emergency,” Wenzel said.

The last audience member to have a comment shared “I appreciate everybody’s effort coming together, working on that. I appreciate you all getting a hold of me that night. My place is the place where all the water comes to be part of it.”