Work on siphon replacement this week will result in traffic slowdown, noise

Later this week, crews will be working on the Ballard siphon replacement project located at Shilshole Ave NW and 20th Ave NW.

Crews will be digging small holes on the north and south sides of Shilshole Ave NW to locate existing underground utilities, according to an update sent out by the King County Wastewater Treatment Division.

Work will take place on Wednesday and Thursday, Jan. 23 and 24. Drivers can expect some slowdown as flaggers will direct traffic through the construction area.

But don't complain too much. King County says the work is necessary to maintain utility services in the area during the relining of the 75-year old existing Ballard Siphon, which will start later this year.

In addition, crews are still building the structure on the north site that will connect the existing sewer pipes to the new siphon pipeline. On Friday, Jan. 25, crews will begin removing shoring from the project area, which could cause some significant noise.

If you recall from our earlier reports, the Ballard Siphon Project will replace the 77-year-old wooden sewer line with a new 84-inch siphon pipe under Salmon Bay. It will run between Seattle’s Ballard and Interbay areas to reduce the potential for sewer overflows into the Ship Canal and to meet north Seattle’s wastewater conveyance needs into the next century.

What to Expect During Utility Work:

  • Flaggers on site to ease congestion
  • Increased noise near the work area from the potholing equipment
  • Work will occur from 7:00 a.m. until 6:00 p.m. on Wednesday and Thursday, January 23 and 24
  • The road will be restored according the City of Seattle standards

What to Expect at the North Site:

  • Possible noise and vibration January 25 through January 31
  • High levels of activity involving crews, cranes, excavation equipment and trucks
  • Increased truck traffic on and around Shilshole Avenue Northwest
  • Shilshole Avenue Northwest sidewalk remains closed in front of the project site

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