Mercer Island water comes up clean, but E. coli advisory continues for at least one more day

The city of Mercer Island says new tests for E. coli and Total Coliform have come up all clear, and some restaurants may be allowed to reopen later on a limited basis Friday.

The city issued an advisory Thursday after tests detected the presence of the bacteria in its water supply. It ordered all restaurants and food service establishments closed, and advised residents boil their water.

The city says crews have been working around the clock to locate the source of the contamination and sanitize the system, pumping in extra chlorine.

The city is also increasing the number of daily samples taken and added sample locations.

More than a dozen restaurants are seeking permission to reopen with limited menus Friday using pre-packaged food. Public Health – Seattle & King County is working with the establishments to determine if there is a safe way to reopen, the city says.

Mercer Island schools remained open Friday, utilizing temporary hand sanitizing stations and distributing thousands of bottles of water and distributing packaged food for meals.

Although the tests came back negative, the city won’t lift the boil advisory until at least Saturday at noon, when the next round of test results will be analyzed and released.

In the meantime, the city continues distributing free water to those in need. Whole Foods Market is offering free use of its in-store water filtering machines at both its South Lake Union and Bellevue outlets for residents willing to make the drive.

Officials say they still have no idea where the source of contamination may have come from, and admit they might never be able to.