Crews with King County’s Wastewater Treatment Division responded to an overflow from a manhole on King County’s North Creek Interceptor, a major regional sewer line in service since 1970, on Dec. 25.

A manhole in a wetland west of the Bothell-Everett Highway between 208th Street Southeast (SR-524) and 214th Street Southeast overflowed for about 60 minutes.

Crews believe a substantial volume of wastewater was captured in a containment structure the County built to protect water quality pending completion of a major capital improvement project to add needed pipeline capacity in that area.

King County reported the overflow to health and regulatory agencies, and employees with the County’s environmental laboratory will sample and monitor water quality in the wetland as well as nearby North Creek over the next few days.

Construction is under way on King County’s North Creek Interceptor Project, which entails replacement of a conveyance pipeline that serves parts of Bothell and unincorporated Snohomish County.

The project includes construction of approximately 10,000 feet of new sewer line and is scheduled for completion in 2016.

Detailed information about the project, including maps, is available at http://www.kingcounty.gov/environment/wtd/Construction/North/NCI.aspx.