On September 8th, 2025, highway traffic on HWY 12 will be diverted onto Tieton Reservoir Road while a construction project is performed by WSDOT.
Message boards will be placed in advance by WSDOT to notify the public. Although the closure has been requested through the end of October, it is expected that work will be completed prior to that date. The most current expected re-opening date for HWY 12 is October 10th, 2025. During the closure, the detoured route will have portions of Tieton Reservoir Road with legally established speed limits. The legal speed limits will be as low as 35 mph in some areas, and the legal limit will be as high as 50 mph in other areas. Please view the detour map for more information. These speed limits are considered temporary for construction only at this point in time.
UPDATE 8/28/2025: A detour map has been provided and is available online here. The start date has been changed to September 8th, and the contractor has October 10th as a tentative reopening date.