Paving on the South Right of Way of Shilshole Avenue Northwest

This in from King County about work on Shilshole Ave. NW:

Paving on the South Right of Way of Shilshole Avenue Northwest to Impact Traffic July 10-17

El pavimento al sur de la derecha de la Avenida Shilshole Northwest impactará el traficó el 10-17 de julio

To protect public health and the environment, King County is continuing to build a new 84-inch siphon pipe under Salmon Bay between the Ballard and Interbay areas of Seattle. The project will prevent sewer overflows into Salmon Bay and sewer backups in North Seattle homes and businesses.

Beginning tomorrow, July 10, crews will be grinding the existing asphalt and paving the south shoulder of Shilshole Avenue Northwest near the Ballard Siphon project site (see map below). The paving will support a detour around the project site when it extends into Shilshole Avenue Northwest later this summer; see below for more information.

During paving, Shilshole Avenue Northwest near Northwest Dock Place will be reduced to alternating one-way traffic between 9 a.m. and 3 p.m. Crews expect to complete this work by July 17 and will not be working weekends.

What to Expect During Paving Work:

  • Alternating one-way traffic on Shilshole Avenue Northwest near the project site from 9 a.m. to 3 p.m.
  • Traffic control signs and flaggers to ease congestion through the area
  • Parking restrictions in work area
  • High levels of activity and increased noise and truck traffic
  • Access to businesses on Shilshole Avenue Northwest will be maintained at all times
  • Typical work hours Monday through Friday, from 7 a.m. until 6 p.m.

Please use caution and follow posted traffic signs and flaggers.

Please plan for extra travel time when driving through this area.

Bicyclists and pedestrians are encouraged to use Ballard Avenue or Leary Way to detour around the site.


Detour Begins in Late Summer on Shilshole Avenue Northwest

El desvío comenzará a finales de verano en la Avenida Shilshole Northwest

Beginning this fall, the existing Ballard Siphon will be re-lined once the new siphon is complete and wastewater flow is transferred to the new siphon. The new pipe and existing siphon will accommodate growth in north Seattle and meet north Seattle’s wastewater needs through the end of the century.

This work requires the construction area to extend into Shilshole Avenue Northwest in front of the project site between 20th Avenue Northwest and Northwest Dock Place (see map below).

Traffic traveling west on Shilshole Avenue Northwest will be detoured to Leary Avenue West for approximately four months.

Westbound bicycles and pedestrians will be detoured to Ballard Avenue Northwest and should follow posted detour routes (see map below).

Eastbound traffic, including bicyclists, will remain on Shilshole Avenue Northwest.

What to Expect During the Detour:

  • Westbound traffic detoured to Leary Ave NW for four months late summer through the fall
  • Traffic control signs and flaggers to ease congestion
  • Increased truck traffic along detour route
  • May include parking restrictions along detour route
  • Access to businesses on Shilshole Avenue Northwest will be maintained at all times

24-hour project hotline/Para más información*: 206-296-3848

*Seleccione su idioma para solicitor hablar con un intéprete, este servicio es gratuito.

For more information on the Ballard Siphon Replacement Project, visit the project website at:

View construction photos here: