Basalt Creek Parkway opens; Tonquin Road closes

For Immediate Release: Friday, August 11, 2017

Sponsored by: Department of Land Use and Transportation, Capital Project Services Division

Basalt Creek workBasalt Creek Parkway, a new 0.7-mile road between Grahams Ferry and Tonquin roads, opens to traffic at 6 a.m. Monday (August 14).

Tonquin Road detourBasalt Creek is part of the SW 124th Avenue Extension project, which connects the cities of Sherwood, Tualatin and Wilsonville. Basalt Creek has one travel lane in each direction with intermittent turn lanes. It includes a 100-foot bridge over the Portland & Western Railroad tracks, which was built to accommodate two additional travel lanes and a turn lane in anticipation of future transportation demand as the area develops.

124th Avenue Extension: The next phase

Starting Monday, a portion of Tonquin Road will be closed, west of Grahams Ferry Road to Basalt Creek Parkway, through April 30. Traffic will be detoured onto Basalt Creek Parkway. (See map). Tonquin Road will remain open to local traffic. The existing two travel lanes will be widened and intermittent turn lanes will be added.

At the same time, the Willamette Water Supply Program (WWSP) will install a portion of a 66-inch water transmission line under Tonquin. Once the installation is complete, the 2.7-mile water line will travel from 124th Avenue, south from Tualatin-Sherwood Road, then east on Tonquin Road and south on Grahams Ferry Road.

"This project represents a great partnership between Washington County, WWSP and the cities of Sherwood, Tualatin and Wilsonville," said Andrew Singelakis, director, Washington County Department of Land Use &Transportation. "The coordination of roadwork and the WWSP water transmission line is minimizing traffic impacts and saving money by reducing construction and project management costs."

In all, the 124th Avenue Extension project is expected to be complete in late 2018. It involves 4.4 miles of new and improved roadway, including:

  • Realignment of the intersection of Waldo Road, Knife River access and Tonquin Road. (Complete)
  • Widening of Grahams Ferry Road (between Tonquin and Day roads) to include continuous turn lanes and bicycle lanes. (Scheduled 2018)

For more information, visit the 124th Avenue Extension webpage, the Washington County Department of Land Use & Transportation FY2015-16 Annual Report and the Willamette Water Supply project map. For the latest road construction schedules, visit

Washington County is committed to planning, building and maintaining a great transportation system, ensuring the safety of all roadway users, and operating the County roadway system in a cost-effective and environmentally responsible manner.

Media Contact:

Melissa De Lyser, Communications Coordinator