County completes emergency bypass pipe for Lake SerenePublic invited to weigh in on plan for permanent fix of periodic flooding
An emergency bypass pipe on Lake Serene is already lowering the water level, providing temporary relief for some 95 property owners whose yards and basements flooded again this year.
Lake Serene is located in unincorporated Snohomish County, west of Highway 99 between Mukilteo and Lynnwood. For years, residents around the lake have experienced flooding during winter months or during periods of heavy rainfall.
Snohomish County Public Works crews completed the pipe Friday, March 10 after 16 days of work in which crews laid 537 feet of pipe and four catch basins, and coordinated the replacement of six water lines and one sewer line.
“I am proud of the work that has been done,” Public Works Director Steve Thomsen said. “Given the quick turnaround that was needed to respond to this emergency, all of Public Works collaborated on making this successful.
“In particular, Surface Water Management’s drainage team did a great job quickly pulling together a buildable, effective project, and our Road Maintenance crews worked tirelessly every day for more than two weeks to construct this project.”
The project is designed to lower lake levels about one foot below the highest recorded water levels on Feb. 17.
The lake has fallen more than 6 inches in the past few weeks, and the project will lower the lake level about another 7 inches, according to county officials.
County staff will monitor lake levels and downstream flows throughout the day to ensure that the system is functioning as expected and does not cause downstream drainage problems.
The cost of the emergency bypass pipe is estimated at $215,000. It was paid for with Snohomish County Surface Water Utility fees, which are generated by all property owners in the watershed.
"The quick completion of the bypass pipe is a great relief," Snohomish County Councilmember Stephanie Wright said. "I appreciate the work of everyone involved in developing this project to protect both homes and infrastructure."
In early January, the existing private drainage system became almost entirely blocked, water levels in the lake rose and Serene Way was at risk for flooding.
County Executive Dave Somers issued an emergency order Feb. 13, and work on the emergency bypass pipe began almost immediately.
The pipe is designed to protect Serene Way and other public infrastructure from flooding and provide some relief to lakeside property owners, according to county officials. It connects to an existing downstream drainage system.
“In just over two weeks, we were able to address the flooding emergency and devise a sensible solution to a complex problem,” County Executive Dave Somers said.
“We are confident this will protect both public infrastructure and lake residents from the worst flooding. Our crews worked through cold, sleet, snow and rain to get this done. They deserve our gratitude.”
Also on Feb. 13, the Snohomish County Council introduced legislation to approve a permanent fix to the periodic flooding on Lake Serene, since the existing emergency bypass will only relieve the most extreme events.
A public hearing is set for 10:30 a.m. March 22 to consider the legislation. The hearing will be held in the council chambers in the Administration East Building at 3000 Rockefeller Avenue in Everett.
The County Council is expected to vote on a decision following the hearing.
Under the proposed legislation, the county’s surface water management utility would pay most of the cost to protect public property. Lakefront property owners would pay an additional $197 per year for 10 years. That would cover the extra cost to reduce lake levels beyond what is required to protect county roads and public safety.
With that money, the county would begin a project this summer to construct a new pipe along the only public access point to the lake: the boat launch. That pipe would bypass the collapsed section that runs through private property and connect to the remainder of the old pipe. The county would own and operate the new outlet of the lake.