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Wastewater Treatment

King County, Washington

For questions about the Wastewater Treatment Division website, please send an e-mail message or contact us at:

King Street Center
201 S. Jackson St., Suite 500
Seattle, WA 98104-3855
Phone: 206-477-5371
Fax: 206-684-1741
Telecommunication device for the deaf (TTY): 711

Get Directions to our office location in Seattle, Washington.

Staff Contacts

North Creek Interceptor Project

Project construction phase

Update, September 21, 2015

Pipe installation continues at 208th Street Southeast

Beginning the week of September 21st, crews will install pipe under 208th Street Southeast (SR 524). No work will occur on the north side of 208th Street Southeast or on 14th Drive Southeast during the crossing, so no road closures or detours are expected. King County’s contractor will continue work in the wetlands on the south side of SR 524 in October.

View construction update (PDF, September 18, 2015)

See Project Description to learn more details about the project and to sign up for construction updates.

NCI project newsletter, February 2015

The North Creek Interceptor sewer project construction

Click on map for project description.
Vicinity map for North Creek Interceptor Project
Vicinity Map for North Creek Interceptor Project

King County has completed final design for the project. A contractor has been selected and is expected to start work in early 2015. The project should take about two years to complete.

Construction will include building 10,000 feet of pipe along a two-mile route from above 208th Street Southeast in Snohomish County on the north end of the project to 228th Street Southeast in Bothell on the south.

There will be a number of different types of activities at various work sites. King County will work closely with businesses, residents and the community in each area of work.

Need for project

The North Creek Interceptor is an important part of the regional wastewater system that serves portions of Bothell, Mill Creek and unincorporated Snohomish County. It carries flows from local jurisdictions to King County treatment plants. Construction will improve the sewer lines by providing additional capacity and needed upgrades to ensure safe and reliable operations for the future.

Being a good neighbor

King County is committed to being a good neighbor and will work directly with the community throughout the project to minimize construction impacts whenever possible. Residents can expect:

  • Advance notice of construction activities – mail, email, phone, door hangers
  • One-on-one problem solving with residents directly impacted by construction activities
  • Construction updates and news via notices, emails, and this website.
  • Project construction information line: 206-205-9795

Project alerts / updates

How to reach us