what we do


Designing connections that balance regional mobility and local access

From rural highway off-ramps to complex freeway interchanges, Parametrix helps agencies plan and design interchanges that safely and efficiently move traffic from one road to another. We help agencies with freeway and local operational analysis for highway and local corridors, and have provided analysis for numerous interchange justification reports (IJR), interchange modification reports (IMR) interchange access modifications, and corridor studies. Our staff have developed great working relationships with FHWA and state DOT staff and can guide you through the approval process.

West Olympia Access Study and IJR | Parametrix
West Olympia Access Study and IJR 
Olympia, Washington
Client: City of Olympia and WSDOT
Partner: SCJ Alliance

The West Olympia Access Study (WOAS) has been a multi-year effort to improve mobility and access on the west side of Olympia. The initial phase was the WOAS that involved technical traffic analysis and alternatives screening to identify future transportation system improvements on both the freeway and local street network to accommodate anticipated growth. This led to an IJR and technical studies for US-101 between the interchanges with I-5 and Evergreen Parkway. This phase involved a corridor-level IJR; NEPA and SEPA environmental documentation; conceptual and preliminary design of a new half-diamond interchange at Kaiser Road; auxiliary lanes on the US-101 mainline; and modification of the Black Lake Boulevard interchange to provide a new westbound-off connection to Yauger Way.



  • SR 410/Traffic Avenue Interchange

    SR 410/Traffic Avenue Interchange

  • 116th Interchange at I-5

    I-5/116th Street NE Interchange

  • I-84 Karcher to Franklin | Parametrix

    I-84 Karcher to Franklin

  • I-5/Slater Road IJR | Parametrix

    I-5/Slater Road IJR

  • I-84 Meridian Road Interchange

    I-84 Meridian Road Interchange

  • West Olympia Access Study and IJR | Parametrix

    West Olympia Access Study and IJR