Highway 501/ I-5 interchange work starts this month

The second stage of a two-part project aims to further remake the busy interchange at Interstate 5 and state Highway 501 in Ridgefield. The final leg of the $29 million job is expected to kick off at the end of this month, according to the Washington State Department of Transportation.

Workers plan to install a pair of roundabouts that will flank the freeway on Highway 501 — at 65th Avenue to the east, and South 56th Place to the west. Planners hope the additions help the functionality and safe

ty of two intersections now controlled by stop signs, said WSDOT spokeswoman Abbi Russell.

“The point is just to keep traffic moving,” Russell said. “No matter what time of day it is, traffic just flows. You don’t have to stop, unless somebody is coming.”

The goal is to improve traffic flow into an interchange that carries about 11,000 vehicles daily, according to WSDOT, working jointly with the city of Ridgefield.

The first stage of the project built a new Highway 501 bridge over the freeway, open to drivers since 2010, and cost $24 million. This year’s work carries a price tag of about $5 million.

The new roundabouts won’t be the first for Ridgefield. Highway 501 already sends drivers through one roundabout to the west.

Starting April 23, the park and ride lot at Pioneer Street and 65th Avenue will close while crews move equipment into place. The lot is used mainly by carpoolers, according to WSDOT, who may instead use the Salmon Creek Park and Ride, near the northern convergence of I-5 and Interstate 205. The Woodland Chamber of Commerce also offers a park and ride lot just north of Ridgefield, at I-5 Exit 21.

Construction at Highway 501 is scheduled to begin April 30 and should finish by this fall, according to WSDOT.

Drivers should expect lane closures, traffic shifts and other delays during construction. Plans call for workers to start on the east side of the freeway first, Russell said.

Eric Florip: 360-735-4541; http://twitter.com/col_enviro; eric.florip@columbian.com.