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Closure of State Route 169 in Maple Valley, Friday, Oct. 15 at 9 p.m. to Monday, Oct. 18 at 5 a.m., for construction to reduce flood risk


State Route 169 north of Cedar Grove Road in Maple Valley will be closed Friday, Oct. 15 at 9 p.m. until Monday, Oct. 18 at 5 a.m. so crews can replace two culverts to reduce localized flooding and improve fish passage.


Travelers who use State Route 169 in Maple Valley willrsz_kcfcd_21 need to detour around the full weekend closure of the highway in the vicinity of a significant flood risk reduction project this weekend. 

Both directions of State Route 169 will be fully closed between 196th Avenue Southeast and Cedar Grove Road Southeast, beginning Friday, Oct. 15 at 9 p.m. and Monday, Oct. 18 at 5 a.m. The adjacent Cedar River Trail will also be closed while crews work over the weekend.

The project will replace culverts under State Route 169 and King County’s Cedar River Trail, which are undersized and restrict runoff during high-rainfall events. Flooding from runoff causes hazardous road conditions, isolates nearby residences, and has caused repeated closures of the highway – most recently a five-day closure in February 2020.

The King County Flood Control District is funding the repair which will replace the existing 18-inch culverts with 15-foot-wide box culverts to minimize the risk of flooding of the highway and nearby residences. The new culverts will also improve fish passage by allowing unobstructed access to upstream habitat. 

SR 169 closure impacts
King County and the Washington State Department of Transportation are working closely to limit the impacts of the closure of SR 169. Residents and businesses near the project area have been notified about the upcoming closure and planned detour route. Residents in unincorporated King County can get real-time traffic information by checking the My Commute Map and by following the @kcroads on Twitter. Travelers can also find updated traffic information on the @WSDOT_traffic Twitter feed. 

What to expect during closure:
Travelers should allow extra time through the area during the weekend closure.
Local jurisdictions have been notified of the planned detour route.
Local and freight traffic will follow a signed detour route.
This work is weather dependent and subject to schedule changes.
Additional information and updates about the project are available at


The King County Flood Control District is a special purpose government created to provide funding and policy oversight for flood protection projects and programs in King County. The Flood Control District’s Board is composed of the members of the King County Council. The Water and Land Resources Division of the King County Department of Natural Resources and Parks develops and implements the approved flood protection projects and programs. Information is available at