South Magnolia CSO Control Project
August 29, 2014 Update -
On Tuesday, September 2, King County’s contractor will begin installing shoring for a drill pit on the east side of 32nd Avenue West. This work can be noisy, and will last 3-5 days. You can expect more construction activity on the street.
What neighbors can expect during shoring for the drill pit:
• New equipment and materials at the site.
• Increased construction traffic, including oversized loads along the project haul route (32nd to Magnolia Avenue W to Magnolia Bridge) as equipment is delivered
• Increased construction activity, noise and possible vibrations
• The contractor will be monitoring vibration levels throughout the shoring process
What is shoring?
It is a general construction term that refers to methods used to help keep excavations safe and open during underground construction and to prevent surrounding soils from running into the excavated pit. Many different shoring methods can be used depending on the type and size of excavation, surrounding soils, and water table.
Latest construction update: Construction on 32nd Ave W (PDF, August 29, 2014)
South Magnolia CSO basin project area
How will the new CSO facility work? View animation.
South Magnolia basin and project location.
King County is building a new gravity sewer pipeline and an underground storage tank in Magnolia. This facility will store peak combined sewer flows so that discharges of untreated wastewater and stormwater are limited to no more than one per year on a long-term average.
Why does King County need to do this project?
This project is included in a federal consent decree that requires completion by December 2015.
View meeting calendar for upcoming public meetings, and South Magnolia CSO Control Project Timeline (PDF), updated May 2013.