Starting tomorrow morning, crews will be on North Beach testing the sewage pipeline, known as North Beach Force Main that runs from the North Beach Pump Station to the Carkeek Park Pump Station.
Click here for a larger version of the map.
According to the Wastewater Treatment Division of the Department of Natural Resources and Parks, the samples will be taken during low tide periods, so crews will need to arrive as early as 4 a.m. to unload equipment on the beach. The contractor will then install shoring and excavate the top soil layers by using a trackhoe. The crews will then dig around the pipe by hand in order to limit potential damage to the pipeline. The excavated soil will be stored on site, and water from the excavation will be pumped to an infiltration pit on the beach during the work.
Once the pipeline is exposed, crews will support it and install a valve prior to removing a small sample of the pipe. They’ll then close the valve and test the seal before filling the area with the stored soil. There will be King County staff on site to monitor the work and address questions from beach- and park-goers.
The Department of Natural Resources says neighbors and beach users can expect the following:
- Work hours are coordinated with the low tide periods; mobilization on the beach will occur prior to the low tide, potentially as early as 4 a.m. pending approval of a variance by the City of Seattle. People may notice noise and lights in the beach area before daylight.
- Crews with hand tools will access the beach area through Blue Ridge Park in coordination with King County staff.
- A landing craft will be used to deliver a trackhoe and other equipment to the beach, and to remove the equipment once the work for the day is completed.
- An excavator, electric dewatering pumps, and a generator will be used in the beach area.
- Excavated marine soils will be stored on site and used to backfill the excavation.
To learn more about the project, click here.