MERCER ISLAND, Wash. — All properties have been deemed safe after residents of 20 Mercer Island homes were asked to evacuate after a leaking underground water pipe created unstable soil conditions.
Mercer Island City Manager Jessi Bon said she and Mayor Salim Nice met with residents Thursday afternoon and notified "some" residents they could return to their homes. Around 6:30 p.m., all residents were told they could return home.
The residents, who all live near 95th Court Southeast, were notified Wednesday night that they needed to evacuate.
The city discovered the water pipe leak on Wednesday afternoon when a geotechnical engineer reviewed the soil conditions. The leak was located in the water main that's near Southeast 40th Street and 82nd Avenue Southeast. If soil conditions worsen or the water line breaks, that could lead to potential flooding or a landslide, according to the city of Mercer Island.
The pipe provides water to Mercer Island and is owned and maintained by Seattle Public Utilities (SPU). SPU switched water service to the Blue Canyon line Wednesday night, which is owned by Mercer Island and runs along East Mercer Way. It is the backup water line that services the city's two reservoir tanks.
SPU turned off the water to the main line Wednesday night and reduced pressure.
“That was a really important step to reducing risk to a landslide,” Bon said.
Bon said the backup water service is adequately supplying the city's water needs, and residents are not being asked to conserve water. Water quality has not been impacted, Bon said.
City crews were able to isolate a section of pipe that restricts water flow in the area, mitigating the risk of property damage if the water main were to break, according to the city, citing a geotechnical engineer.
The city is working with SPU on repair and assessment. Bon said SPU would excavate the area and repair the leak.
Jackie Tan previously said three firefighters came to her door at about 9:45 p.m. Wednesday informing her of the evacuations. Her family left about 45 minutes later and stayed in a hotel Wednesday night.
Tan said she is worried and uncertain about what is going to happen over the next few days.
"There has been an issue with landslides on this particular street," Tan said.
In January of 2022, a burst water pipe in Bellevue led a home to slide completely off of its foundation due to unstable soil. The home had to be demolished, and the City of Bellevue settled a lawsuit with the homeowners for $3 million.