Water Main Break Repairs and Road Closure Update

Update: 08/08/2025

City Declares Local Emergency to Address Water Main Breaks

The City of Mercer Island has declared a local emergency due to the impacts of multiple water main breaks along East Mercer Way, which occurred on Aug. 5 and 6, 2025. This emergency declaration, under Proclamation No. 365, was issued because the breaks caused water service outages, flooding, and the closure of a segment of the East Mercer Way roadway, impacting the public's health, safety, and welfare. To address the situation as quickly as possible, the City has invoked emergency powers, which includes the ability to enter into contracts and employ temporary workers outside of normal procedures. 

Update: 08/06/2025

Crews worked through the night to repair a water main break near the 8300 block of East Mercer Way. Water service has been restored to approximately 50 affected homes. This break required replacing a section of pipe, which is complex and time consuming to repair. The main has been flushed and the water is safe to drink; there may be some discoloration at first and it should gradually improve. Impacted residents are encouraged to run their water to speed up this process. Contact City of Mercer Island Customer Service at (206) 275-7600 or customerservice@mercerisland.gov to report any issue. 

There is a second water main break near the 7700 block of East Mercer Way (near Clarke Beach Park), which is impacting five homes. Crews are on scene and beginning to complete the repair. These five homes may experience intermittent service disruption while the emergency work is completed.  

The East Mercer Way roadway between SE 76th St and the north end of Clarke Beach Park sustained damage due to the water main break and will remain closed to all vehicle traffic, pedestrians, and bicyclists. Clarke Beach Park is also temporarily closed. A geotechnical engineer has evaluated the site and has recommended that the roadway remain closed until it dries out and is further evaluated. This road closure is anticipated to be in place for at least a week. See the attached map for recommended detours. The Fred Hutch Obliteride bike ride on Saturday, Aug. 9, whose route had been scheduled to use East Mercer Way, will be rerouted.

Updates will be provided as more information becomes available. 

What to do when your water is restored:

City crews have been able to maintain positive pressure throughout the work, isolating the water main and maintaining drinking water standards, so the water is safe to consume. Some cloudiness is expected while the water service is restored. Customers should flush their lines to help clear the cloudiness and possible sediment that may have been disrupted from the work. The most effective way to flush your system is to run *cold* water from the bathtub tap located at the highest part of your home (whatever tub is on the top floor of your home).