SR 161 - 31st Avenue SW Corridor Study

SR 161 - 31st Ave SW Overcrossing - Widening Study - Study map thumbnail

In July 2018, the SR 161 - 31st Avenue SW Study was completed and the report is now available for viewing. With the help of local stakeholders and community members, the Washington State Department of transportation identified three recommended strategies to reduce traffic congestion and improve traffic operations. 

Study Report (pdf 12.4 mb)

Why is WSDOT studying this bridge?

The merge of State Route 161/31st Avenue over State Route 512 in Puyallup is an important overpass for Pierce County residents and business owners. The SR 161 Undercrossing (also known as an overpass) is currently two/three lanes and a known bottleneck for commuters. The overpass is also designated as a functionally obsolete structure. The study will identify solutions to improve the predictable movement of goods and people along the State Route 161 corridor in the vicinity of State Route 512 using practical solution strategies.

The Washington State Legislature directed WSDOT to conduct a feasibility study for widening and improvement of the SR 161/31st Avenue Overpass.

The Next Steps
The feasibility study concluded with three recommended strategies to reduce traffic congestion and improve traffic operations. These strategies will be prioritized on a statewide basis for future implementation, but due to limited state funding, will also compete for funding with other proposed improvements in other areas throughout the state.

Needs & benefits

The intent of this study is to provide a sustainable and integrated multimodal corridor which improves mobility by reducing congestion with bridge widening and non-motorized improvements.


Fall 2016 - Gather data, analyze existing and future conditions and organize a stakeholder working group.
Spring to Fall 2017 - Identify and analyze possible improvement strategies, and stakeholder and community engagement.
Fall 2017 to Spring 2018 - Draft and finalize study report and provide recommendations.


Funding for this study was provided by the Washington State Motor Vehicle Account. A total of $1.1 million dollars was allocated during the 2013-2015 biennium.


Dennis Engel, Multimodal Planning Manager
Phone 360-357-2651