Home » Fremont Siphon Sewer Project Moves Forward

Fremont Siphon Sewer Project Moves Forward

A drawing of the new, microtunnel configuration to replace the Fremont Siphon. Diagram provided by King County

After investigating a range of alternatives, King County has set in place a plan to replace the existing Fremont Siphon – a critical wastewater conveyance line – with a new crossing under the Lake Washington Ship Canal.  Two microtunnels will be built just west of the existing siphon, under the canal, and connected to the North Interceptor conveyance pipelines on the north and south sides.  The new pipes will be designed to the same capacity as the existing system, and the County will retain the nearly 100-year-old Fremont tunnel for other wastewater treatment uses.

During construction, King County plans to build a retrieval pit on the Fremont side of the Ship Canal, which will place a temporary access restriction in a portion of Canal Park.  Construction will also require street work, and affect access along the Burke-Gilman Trail during the project.

A simplistic drawing of the Fremont Siphon. Provided by King County

Next steps for this replacement project include developing a preliminary design, passing the environmental review, settling on a final design and acquiring proper permitting – all scheduled to happen by 2014.  Expect King County representatives to make further presentations to community groups, another community-wide meeting, newsletters, and press releases to keep the neighborhood informed as the project elements develop.

King County has extensive experience working on sewer projects in densely populated urban areas, including in parks and along waterways.  They are committed to working closely with residents, businesses, recreational users and commuters in the our area.  For more information, visit the project web page or e-mail Monica Van der Vieren at monica.vandervieren@kingcounty.gov

A Related Note:

The King County Department of Natural Resources & Parks Wastewater Treatment Division would also like to remind everyone to take care about what they flush.  Think trash, not toilet about these items:  grease, cleaning wipes, hair, disposable diapers, nursing pads and baby wipes, condoms, facial wipes, tampons and pads.  The label might say “flushable,” but disposable wipes and other products are clogging our sewer lines, damaging pumps, and can cause raw sewage overflows.  Don’t flush trouble!

To learn more, including how to get rid of things you no longer want or need, visit the website.