Planning studies

This site features current biennium (July 2019-June 2021) and frequently requested planning studies. If you are unable to find a particular WSDOT planning study, please visit the WSDOT Library's Planning Studies collection and/or contact Michel Wendt at the WSDOT Library at 360-705-7710.

Frequently requested studies

SR 166 - Bay Street / Bethel Avenue / Maple Avenue Intersection Pre-Design Study
WSDOT is conducting a pre-design study of the intersection of SR 166 and Bay Street, Bethel Avenue and Maple Street in Port Orchard. The existing traffic signal has reached the end of its useful life and is in need of being replaced. Through collaboration with local community businesses and technical staff, WSDOT proposes to replace the existing traffic signal with a modern single-lane roundabout. The project is scheduled for design in fall of 2020 and construction is anticipated for summer 2022.

US 195 Corridor Crash Analysis (pdf 10.5 mb)

Current biennium (July 2019-June 2021) planning studies

US 2 Upper Wenatchee Valley Corridor Transportation Study

This study is a joint effort between North Central Region and the Chelan-Douglas Transportation Council to address mobility and safety performance of multimodal travel on US 2 from Coles Corner (MP  84.51) through Leavenworth to Cashmere (MP 110.13). The project team will identify a set of near- and long-term improvements for multimodal travel that include transit, freight, cars, bicyclists, and pedestrians. The project team will work directly with the public throughout the process to ensure that the input and concerns of diverse stakeholders understood, considered and directly reflected in the final recommendations.

Nicholas Manzaro


US 2 West Plains Sub-area Management Plan Phase 1

Eastern Region is leading this study to address the mobility gaps along US 2 between the US 2 and I-90 interchange (MP 283) and the Fairchild Air Force Base entrance (MP 275.33). In order to help alleviate traffic loading directly on to the US 2 corridor, this study looks at other possible parallel frontage road connections for 6th/12th and 18th/21st. This study refines previous studies that have been completed in the West Plains area, which have indicated performance concerns and mobility gaps (congestion) for the US 2 corridor in Airway Heights, as well as a need for a local parallel roadway network. Land use development in the West Plains vicinity is outpacing the available multimodal transportation system in the area. There is a need, particularly in and around US 2, to collaboratively refine past study efforts and plan "practical solutions" using Transportation System Management and Operations (TSMO) low-cost solutions.

Charlene Kay

Bonnie Gow


I-5 Operations and Demand Management Analysis

The Northwest Region Mount Baker Area is leading this effort to address several mobility challenges along segments of the I-5 corridor within the urban area of Bellingham (MP 250 to MP 258). Congestion occurs regularly during peak travel at the I-5 interchanges and on the connecting regional arterials. WSDOT is conducting this analysis to understand when and where congestion occurs, and the travel characteristics of users of this section of the I‐5 corridor. WSDOT will use this information to assess the need for operations, demand management strategies, and evaluate their effectiveness.

Todd Carlson

John Shambaugh


I-5 Tacoma Mall Boulevard Access Study

Olympic Region, in partnership with the City of Tacoma, is leading this study to identify strategies, such as alternative routes, to reduce congestion and address future travel demands around the Tacoma Mall area. The study area includes the I-5 and 38th Street interchange (MP 129.10) and local streets. This study is included in the 2019 Transportation Budget (ESHB 1160).

Dennis Engel

Cara Mitchell


SR 523 145th Street Multimodal Corridor Study

The Management of Mobility Division is coordinating an update to the 145th Street Multimodal Corridor Study (aka SR 523), which was led by the City of Shoreline and completed in 2016. This update will reflect changes to current projects and continued assessment of needs along the entire length of SR 523 from SR 99 (MP 0) to the junction of SR 522 (MP 2.45). This study is included in the Transportation Executive Information System as project L1000148.

Celeste Gilman

Nazmul Alam


SR 240 - Richland Corridor Improvements

Growth in Richland has led to increased congestion at several existing intersections on SR 240 from I-182 (MP34.57) and SR 225 (MP 20.47). South Central is leading to effort to improve safety and mobility performance throughout the transportation network through infrastructure improvements, operational enhancements and transportation demand management strategies. This study is included in the Transportation Executive Information System as project L2000202.

Alex Sanguino

Summer Derrey


SR 303 Corridor Study

The City of Bremerton and Olympic Region have launched a comprehensive study of the SR 303 (Warren/Wheaton) corridor. Using the Practical Solutions approach, the study will look at the corridor from Burwell Street to McWilliams, particularly the segments within city limits. The study will recommend safe, reliable, and cost-effective transportation options that support livability, investment, and economic vitality for people and businesses. 

Katie Ketterer


SR 500/Fourth Plain Operations Study

Southwest Region is studying the intersection of State Route 500 and Northeast Fourth Plain Boulevard in Clark County to identify issues affecting safety, mobility, and travel reliability in the corridor. Recent data has identified SR 500 at Fourth Plain Boulevard (MP 4.44) as having the most traffic congestion and motorist delays of any highway intersection in Clark County.

Judith Perez


SR 518: SR 509 to I-5 - Corridor Planning Study

In 2017, between 73,000 and 131,000 vehicles used SR 518 every day. WSDOT anticipates that considerable growth in nearby communities and the airport will fuel demand and delays at peak travel times. The Management of Mobility Division is leading this study to determine priorities for future highway work or transit service adjustments and  to develop practical, cost-effective concepts to help improve trip reliability and safety along the corridor. This study is included in the 2019 Transportation Budget (ESHB 1160).

Thomas Noyes


I-5 - Tumwater to Mounts Road Corridor Study

Olympic Region, in collaboration with local partners, is studying transportation system performance on I-5 through Tumwater, Olympia, and Lacey. The study area extends from the SR 121/93rd Avenue SE/Tilley Road Interchange in Tumwater (MP 98.68) to Mounts Road, just east of the Nisqually River (MP 116.70). This section of I-5, which transects the Nisqually River delta, experiences congestion, recurring delay, and unreliable travel times. The results of this study will recommend 20-year strategies to address mobility and environmental performance. This study is included in the Transportation Executive Information System as project L1000231.

Dennis Engel

Karen Parkhurst

Bradley Bobbitt


Webpage contact

Candice Tobin
Multimodal Planning