Update on South Magnolia CSO Control Project

King County Department of Natural Resources and Parks, Wastewater Treatment Division

Storage facility

Work continues to build a new  facility that will reduce untreated discharges of sewage and stormwater from the outfall off 32nd Avenue West in heavy rains.

Night work will be completed this evening, Friday, July 25.  The contractor was required to perform work on the Magnolia Bridge on/off ramps at night to reduce traffic impacts.  Work between the ramps was carried out during the day.  The contractor will pave the on ramp tonight, completing the installation of a new pipeline to tie the storage facility to the County’s existing pipeline on Port of Seattle property.  This pipeline carries wastewater to the Interbay Pump Station, located behind the Staples by the Magnolia Bridge.

The storage facility contractor has also completed shoring for the new underground storage tank and is continuing excavation.  Neighbors living above the Magnolia Bridge will experience less noise now that this work and the night work are wrapping up.

An upcoming power outage will be scheduled to connect the new underground power line installed from a point near Palisades restaurant to the storage tank.  Seattle City Light will notify affected customers when the outage is scheduled.

Next week, pavement patch will be laid on West Marina Place and 23rd Avenue West, resulting in traffic detours.  Final paving in this area is scheduled for August 4-8.

Conveyance (gravity sewer pipeline)

The County’s contractor has rapidly mobilized to begin work at both Smith Cove Athletic Field and on 32nd Avenue West.  Later this summer, the contractor will install a pipeline extending 3000 feet between these two points.  On 32nd, the contractor has built a temporary roadway to divert traffic around the area where drilling equipment will be set up to install the pipeline.

Crews working Saturday, July 26 to prepare for water line relocation

Work is underway to relocate underground utilities in the work area on 32nd.  Seattle Public Utilities crews are scheduled to cut and cap a water line on Monday, July 28.  To prepare for SPU to complete this work on Monday, Walsh crews will work a half day on Saturday, July 26.

Installation of steel conductor casings will occur at both Smith Cove Athletic Field and 32nd Avenue West.  The casings, large steel pipe sections, are needed to protect slopes at the entry and exit points for the new pipeline.  People nearby during this work will experience noise and some vibration from this work.  Monitoring of slopes and vibration will be carried out according to contract specifications during this work and drilling operations.

Please feel free to contact the South Magnolia CSO Control Project  24/7 Construction Hotline: 206-205-0968 if you have questions or concerns.