Under Lake Forest Park, Brightwater continues to tunnel

Brightwater Project Update February 2011

from Brightwater staff

Tunneling train used to transport workers and materials emerging at the Point Wells Portal. Photo courtesy of King Co.

The tunnel machine that was launched at Point Wells in fall 2008 completed its four-mile run at the Ballinger site in June 2010. The machine was then reconditioned and in September 2010 began mining east from Ballinger towards Lake Forest Park. This work will complete the final two miles—between Ballinger Way and Lake Forest Park—of the 13-mile long Brightwater conveyance tunnel.

Workers inside a completed tunnel section. Photo courtesy of King Co.

Tunneling operations, including tunnel segment deliveries and barging of material removed from the tunnel, are taking place at Point Wells. The final two-mile section of tunneling from Ballinger to Lake Forest Park is expected to take a year and be completed in fall 2011.

Tunnel construction hours will continue Monday through Saturday from 7:00 a.m. to 12:30 a.m. until the tunnel drive is completed. Occasionally, underground construction will run longer depending on conditions and necessary maintenance stops.

Surface work in Lake Forest Park. Photo courtesy of King Co.

Though almost all of the remaining conveyance work is below ground or at one of the portal sites, there is surface work being done on 53rd Avenue Northeast, a residential street in Lake Forest Park. 

This construction is to support the final tunnel connection 320 feet below ground. Prior to making this connection, it is necessary to stabilize the deep ground where the two tunnels will be joined. The work on 53rd involves drilling and installing freeze pipes to circulate chilled salt water to freeze the ground around the tunnel where the final connection of the Brightwater tunnel system will be made later this year.

Visit the project web site  to learn more about our project. You can also email or call 206-263-9453 if you have questions or want to sign up for project updates.