SR 160 Planning Study

SR 160 Long Lake Rd SE Planning Study

SR 160 Long Lake Road Planning Study Map

In March 2018, the SR 160 Long Lake Road SE Planning Study was completed and the report is now available for viewing. With the help of local stakeholders, and hearing directly from community members, the Washington State Department of Transportation narrowed the preferred alternative to a roundabout at the intersection of Southeast Sedgwick Road (State Route 160) and Long Lake Road.  

Study Report

Executive Summary (pdf 159 kb)

Study Report (pdf 8.6 mb)

Planning Study Description

State Route 160 (Sedgwick Road) is an important east-west connection that provides primary access between State Route 16 and the Southworth Ferry. SR 160 also serves local drivers, and regional commuters.

WSDOT completed a study of SR 160 between Phillips Road and Mayvolt Road Southeast/Lake Valley Road Southeast. The purpose of this study was to develop intersection control strategies that have the potential to reduce the frequency and severity of crashes at the intersection of SR 160 (SE Sedgwick Road) Long Lake Road Southeast.

This section of highway is classified as a rural two lane highway. The existing highway has narrow shoulders, and it has numerous intersecting streets and driveways. Drivers using Long Lake Road SE wishing to enter onto SR 160 currently have a stop sign.

WSDOT examined five possible alternatives for this intersection, with the preferred alternative being a single-lane roundabout at the intersection of Southeast Sedgwick Road (State Route 160) and Long Lake Road.

Needs & Benefits

The Long Lake Road SE intersection has been identified as a location in need of safety analysis due to the type, frequency and severity of crashes. Using WSDOT's performance-based approach to transportation decision-making, WSDOT evaluated and documented the roadway conditions on the state transportation system in the study area.


WSDOT, working with community members, identified and recommended a suitable alternative that will meet current and future needs.

The End Result

WSDOT produced a recommended alternative to address the needs at the intersection of State Route 160 and Long Lake Road Southeast. The study report will guide WSDOT moving forward in identifying future solutions.


Funding for this study was provided by the Dedicated Federal Highway Safety Improvement Program ($192,000) and the Washington State Motor Vehicle Account ($8,000). A total of $200,000 was allocated during the 2015-2017 biennium.


Fall 2016

  • Data collection
  • Develop scope of work
  • Preliminary data analysis

Spring 2017

  • Stakeholder communication
  • Community engagement

Summer 2017

  • Stakeholder communication
  • Community engagement
  • Data analysis
  • Safety analysis
  • Finalize options

Fall 2017 - Spring 2018

  • Community Engagement
  • Complete study report
  • Publish report


Dennis Engel, Planning Manager

Yvette Liufau, Study Lead