Drivers should plan ahead for long delays and take alternate routes this weekend as crews completely close a portion of eastbound SR 520 in Redmond.

Crews will close all lanes of eastbound SR 520 between SR 202 and Avondale Road from 10 p.m. Friday, July 23, to 5 a.m. Monday, July 26.

During the closure, crews will pave the highway and move barrier to create a new work zone and begin construction in the median. Until now, crews have been working on the north and south sides of the highway.

“We need 30 percent of drivers to take another route or delay their trips,” WSDOT Traffic Engineer Brian Dobbins said. “The backups are expected to be similar to that of a bad afternoon commute.”

Detours will be posted for drivers to follow. All eastbound SR 520 traffic will exit at SR 202, take a right onto SR 202, left onto 180th Avenue SE, and left onto Union Hill Road to Avondale Road.

Drivers headed for the Sammamish Plateau are encouraged to take I-90 to East Lake Sammamish Parkway. Drivers coming from I-405 can use SR 908 to get to downtown Redmond.

WSDOT will work with the city of Redmond to keep traffic moving as much as possible along the alternate routes. Engineers will retime signals and police officers will be on standby to direct traffic if necessary.

This work marks the final phase of a project to widen SR 520 in Redmond by adding a new merge lane and HOV lane to both directions between West Lake Sammamish Parkway and SR 202. When it’s completed later this year, it’s expected to increase commute speeds, eliminate a chronic congestion chokepoint, reduce sideswipe collisions and is part of an overall plan to improve traffic flow on SR 520 and SR 202.