The replacement of the 100-year-old Fremont Siphon has begun, and traffic detours will be part of this almost two-year-long construction project. The King County Wastewater Treatment Division wants everyone to be aware, and prepared, for the impacts of this project.
On Thursday, May 14th and Friday, May 15th, access to NW Canal St from 2nd Ave NW will be closed. Crews will be finding underground utilities and preparing for relocation of a City of Seattle water pipe and overflow storm drain. Local vehicle traffic can access the alley north of NW Canal St through the parking lot west of 123 NW 36th. Burke-Gilman Trail users should follow the detour south of the trail to get around the work area safely. Normal traffic patterns will return to normal when in-street work is not required.
Very soon, crews will also begin installing a watertight ring of concrete cylinders called secant piles, before digging the launch shaft for the tunneling machine. The watertight ring keeps groundwater out of the shaft area and protects against settlement.
Construction on the siphon replacement will be done from 7a – 6p weekdays, and 9a – 6p on Saturdays as needed. Noise and other disruptions will be a part of this project. Please avoid the project area, and sidewalks next to the project area, and do not engage individuals working at the site in conversation or other distractions.
Most importantly, any and all questions and concerns can be directed, 24 hours a day, to the project information line at 206/205-5428.