Local Information

Lacey: I-5/Marvin Road diverging diamond interchange work kicks off

Monday, October 29, 2018 - 10:35

Doug Adamson, communications, 360-357-2716

New design improves traffic flow, reduces potential for collisions

LACEY - Users of the Interstate 5/State Route 510 (Marvin Road) interchange will get a front-row seat as work kicks off to build Washington state’s first diverging diamond interchange. The project will reconfigure the existing overpass.

“We’re using proven innovation to help meet Lacey’s growing needs,” said Washington State Department of Transportation Regional Administrator John Wynands. “This type of interchange helps move traffic more efficiently, reduces the potential for collisions and provides enhancements for bicyclists and pedestrians.”

Crews began installing orange signs earlier this month, marking upcoming construction. Drivers initially can expect shoulder closures on I-5 and Marvin Road. As work progresses, construction will require lane and ramp closures and traffic shifts.

WSDOT will work to keep traffic moving during the two-year construction effort. WSDOT posted a new video showing the initial phases of work travelers can expect to encounter.

When construction wraps up on the $48 million project in late 2020, the transformed overpass will allow drivers to make free left turns onto I-5. A diverging diamond interchange intuitively guides drivers to the left side of the overpass via traffic signals, barriers and road striping.

Other benefits of the new interchange include:

  • A barrier-separated path for bicyclists and pedestrians across the overpass.
  • Southbound I-5 direct access to Hogum Bay Road via a dedicated right turn lane.
  • Direct access to planned Hawks Prairie development via the on-ramp to southbound I-5.

For project updates – including advance information about construction – and a virtual drive-through, visit I5exit111.com.

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