When a casino, resort, and tribal center for the Cowlitz Tribe were developed, it was determined the existing interchange was not sufficient to safely and efficiently support the near- and long-term increases in traffic volumes. Kittelson was hired to lead a multidisciplinary team to study, plan, and functionally design the new interchange and modify the nearby local roadway network.

While privately funded, the study and design were closely coordinated with the City of La Center and WSDOT to ensure standards and design expectations were met at multiple levels of government. The Kittelson team was required to perform the evaluation and design work in an open and collaborative manner to verify the design met local needs and was consistent with the most recent national guidelines.



Kittelson’s design incorporated a new interchange bridge with modified ramps and roundabout controlled terminals, as well as significant ped/bike improvements and multi-use pathways. To support the NEPA environmental review process, Kittelson completed the re-evaluation report and interchange justification report. The project team realigned approximately two miles of local roadways to improve safety and circulation, to meet WSDOT’s access management requirements for crossroads and address projected traffic volumes.

The Outcome

A Roundabout Way to Modify a Crowded Interchange

Kittelson’s work, via an open and collaborative design process, resulted in an aesthetically pleasing, low maintenance, and safe new gateway to the City of La Center and Cowlitz Reservation that supports long-term traffic demands and ped/bike activities. The firm successfully managed a multidisciplinary team and coordinated the legal team and local agencies to deliver to WSDOT, the City of LaCenter and the Cowlitz Tribe the new $40 million interchange. Three roundabouts and multi-use paths introduced to the interchange area have resulted in lower maintenance costs, and improved safety.




Mohegan Gaming Advisors, LLC


Cowlitz Reservation