SR 161 - 31st Ave SW Overcrossing - Widening Study

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

WSDOT study team with help from local stakeholders and community members have identified three recommended strategies to reduce traffic congestion and improve traffic operations. The analysis looked at improving traffic operations along 31st Avenue SW (and SR 161) from the intersection of 31st Avenue SW and 9th Street SW/94th Avenue E to the intersection of SR 161 and 35th Avenue SE.

Additional work including the study's vision and need statements and community engagement efforts were important in developing the recommended strategies. 

  • Vision Statement: Provide a safe and efficient multimodal transportation system that improves mobility by reducing congestion consistent with anticipated growth.
  • Problem Statement: Traffic volumes over the SR 161 bridge exceeds current capacity leading to traffic queuing, traffic delay, and multimodal limitations.
  • The study online open house was completed on Nov. 6. Thank you to all those who participated and provided feedback. View the online open house survey results (pdf 562 kb).

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 is 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

Nazmul Alam, Study Lead
Phone 360-704-3207

Claudia Bingham Baker, Communications Manager
Phone 360-357-2789