Laura, a project lead with the Washington State Department of Transportation, gave a detailed update on the I‑5/170 Ninth Street interchange improvements project and said, “The interchange project will improve safety and mobility at the interchange, by replacing the existing signals that are out there today with roundabouts.”

The project would replace the existing signalized ramp terminals with two roundabouts, replace the two bridges that carry I‑5 over 170 Ninth Street, raise I‑5 about 4–5 feet in the project area, lengthen the southbound off‑ramp, add ramp meters, build two 10‑foot shared‑use paths north and south of 170 Ninth Street, and replace a fish‑blocking pipe with an open‑channel stream that provides roughly an 18‑foot minimum opening beneath ramps and bridge spans. Laura said the project also includes drainage treatment, updated traffic technology, lighting and acquisition of property rights “as needed to just support the the.”

Why it matters: the corridor serves commuters, freight, event traffic for the county fairgrounds and an amphitheater, businesses and many residences; officials said the improvements aim to reduce serious crashes, keep traffic moving during events and everyday use, and support local development. Laura said the project was first identified in the Connecting Washington funding package (2015) and received design funding in 2024; she said the team plans to advertise the interchange project for construction in 2028, begin construction in 2029 and build through about 2031.

Clark County projects that tie into the interchange include the DelVal realignment project (south and north DelVal realigned to meet at one intersection), a Fifteenth Avenue extension to connect to Tenth Avenue, and a Fifteenth to 206th Avenue project; WSDOT officials said those county projects are timed to coordinate construction so the corridor functions as a system. Laura noted WSDOT will design and oversee the I‑5 bridge and ramp work and that a small gap segment between the interchange and county work is included in the state project.

Residents asked how event traffic for the amphitheater and fairgrounds would be handled. Brian, a project manager working with the state presentation, said the design and modeling accounted for adjacent demand and that “manual control is about 5 to 8 times a year based on historical experience,” but that the roundabout configuration and temporary lanes at one County roundabout are intended to reduce the need for manual flagging. Brian added that temporary manual control would still be required for some large events.

Several residents voiced skepticism about roundabouts and cited recent local examples that, in their view, produce backups. Laura and Brian described traffic modeling and site‑specific design adjustments — including truck aprons and entry angles — used to test whether roundabouts will perform at this location. Laura said roundabouts “are very efficient at moving traffic” and tend to reduce severe, injury crashes by slowing vehicles, and that the public vehicle survey (truck lengths/axles) helped tailor the design for freight movements.

On property acquisition and schedule risk, Laura said WSDOT’s real estate services group would appraise needed parcels and work to purchase right‑of‑way at fair market value; she acknowledged that environmental review and right‑of‑way processes can be the longest parts of a project schedule. When asked how pedestrian crossings are being handled, Laura described shorter crossing distances, refuge islands and orienting ramp crossings so drivers are looking toward pedestrians.

The presentation also covered fish passage: the existing pipe under I‑5 will be replaced by an open channel routed beneath one of the new I‑5 spans and the ramps, connecting to a stream segment the county will build as part of the DelVal work.

What’s next: officials said they will complete design, environmental review and permitting, develop construction staging and an event‑management plan, and hold another open house in 2026. WSDOT staff provided the project website and an email signup for updates. Residents were encouraged to submit input during the design phase.

Ending: WSDOT and Clark County officials stressed ongoing coordination among multiple projects along the corridor; residents were invited to the 2026 open house and to contact the project team through the project webpage for more information.