The 219th Avenue interchange is a relatively recent addition to the I-5 corridor; it was dedicated on Oct. 16, 2008.
Most of the other I-5 interchanges in Clark County date back to the original construction of the freeway, although some have seen upgrades over the years – most recently a major expansion of the Cowlitz Way and Northwest La Center Road interchange in 2016, coinciding with the development of ilani.
The new Ridgefield connection would take off from the 219th Street overcrossing and continue west for approximately 1 1/2 miles to connect with Northwest 31st Avenue, which becomes Hillhurst Road after it crosses Williams Road heading north toward Ridgefield.
Pioneer Street is Ridgefield’s “main road in and out of town” and its only direct freeway connection, Kast said, so the project is billed as a way to improve traffic flow and provide an alternate route for emergency vehicles.
The benefits could extend beyond just Ridgefield, Kast said – traffic studies show that some motorists who use the Northeast 179th Street exit and follow back roads north to Ridgefield would likely shift to the new connection.
“The traffic model showed that all the interchanges from 179th up to La Center will benefit from having this additional connection,” he said.
The project is still at least five years away from breaking ground, but Ridgefield has taken the lead in a public outreach campaign to gather feedback about the proposed connection and possible routes. The website at Ridgefieldroundtable.org/i5-south-connection includes a survey that will remain open through April 5.
The project’s website lists seven possible routes under consideration for the connection, most of which head west from the interchange to land at various points along 31st Avenue, and would consist almost entirely of new right of way.
The one partial exception is an option that would head north and connect with Northwest Carty Road, which would then ferry drivers west. That version of the project would dovetail with a separate planned upgrade to Carty Road, according to Kast.
“That’s sort of our backstop proposal,” he said.
All of the possible routes would be two-lane roads and would likely not include any development along the corridor, Kast said, because they would fall outside the city limits. The exact routes vary slightly based on how factors such as overall length and impact on existing properties are prioritized.
The various routes all have projected price ranges between $50 million and $62 million, according to the project website, except for the northern option, which would cost $40 million to $45 million, although the separate Carty Road upgrade would cost another $50 million to $55 million.
All of the routes would likely involve upgrading the intersection on the east side of the freeway into a roundabout to handle the increased traffic. Traffic circles could also be used at the west end, Kast said, although the upgrades are still under consideration.
“Obviously being Ridgefield, we love roundabouts,” Kast said. “It’s sort of our go-to preferred intersection configuration, but it makes a lot of sense over there too on the east side of the project.”
After the public input phase, the next step will be to work with the county to seek design funds, Kast said, with the goal of starting construction within the next 10 years.