US 12 - Wallula to Nine Mile Hill - Build New Highway

Project News

In 2015, the Washington State Legislature provided funds for the Phase 8 roadway design and right of way acquisition as part of the Connecting Washington transportation funding package. Design and right of way acquisition are scheduled to begin in fall 2018 and fall 2020, respectively. A public open house for the US 12 corridor was held in Touchet on March 15, 2018. View the open house display boards on Flickr. The project overview map has been updated since the March 2018 open house. View the updated project overview map on Flickr. 

Needs & Benefits

Since 2003, WSDOT and the US Highway 12 Coalition have made significant progress toward widening US 12 from two to four lanes from the Snake River (near Burbank) to Walla Walla. Phase 8 will complete the approximately 10 miles of new four-lane divided highway that remain between Boise Inc. and Nine Mile Hill after Phase 7 is finished.

Completing this new section of US 12 highway will benefit the residents, businesses, and traveling public through improved safety, capacity, and mobility. In addition, the regional transportation system between the Tri-Cities and Walla Walla will better support the agriculture, the wine industry, and other freight traffic critical to Eastern Washington’s economic vitality. 

Project benefits include:

  • Increased safety: The proposed four-lane highway will improve safety by separating opposing traffic with a median. Grade-separated intersections with local roads will allow access to and from the new roadway. Building a four-lane highway will also ease conflicts between slow moving trucks and passenger vehicles.
  • Reduce congestion: A four-lane highway will improve traffic flow and provide improved passing vehicle movements.
  • Freight mobility:  Commercial trucks make up as much as 12% of traffic on US 12 in this area. Increasing capacity will reduce slowdowns and improve travel time for freight, tourism, recreational, and commuter traffic.
  • Economic:  Once complete, the new four-lane highway will connect Walla Walla to the western ports and enhance mobility within the region and state.


  • Fall 2018: Phase 8 will begin design 
  • Fall 2019: Phase 8 will begin right of way acquisition 
  • WSDOT plans to break ground for Phase 8 when construction funding becomes available


This project is partially funded by the 2015 Connecting Washington revenue package.

Funding Source ($ in thousands):

  • 2015 Connecting Washington: $34,000
  • Unfunded: $161,000
  • Total: $195,000


Bob Hooker
WSDOT Project Engineer
Design Project Engineer Office

US 12 Phase 8 map

US 12 Wallula to Nine Mile Road aerial