UPDATE: Sunday, 10:15 a.m. | All residents of Mercer Island must continue to boil tap water before drinking it, or use bottled water, according to the mercergov.org website.
Authorities expect the next round of test results around midday Sunday. There are no reports of illness at this time, according to the site.
Due to the water-boil alert, the regular Sunday morning Mercer Island Farmers Market has been canceled.
ORIGINAL POST | All water customers on Mercer Island are being advised to boil their water before drinking it, or use bottled water, until further notice after tests showed the presence of E. coli bacteria in the water system, the city said Saturday.
In addition to the boil advisory for residents, Public Health — Seattle & King County has ordered all food establishments, including restaurants, coffee shops and delis on the island, to close until the warning is lifted. Officials said the number of affected establishments is less than 100. Health inspectors also plan to give guidance to schools, childcare, long-term care and skilled nursing facilities.
The advisory, announced Saturday afternoon, recommends that boiled or purchased water be used for drinking, making ice, brushing teeth and food preparation.
Water is safe for bathing, according to the advisory.
Evidence of the bacteria, which can cause diarrhea, cramps, nausea, headache or other symptoms, was found in four of six water samples during a routine test Friday. More samples were tested Saturday but officials won’t get the results until Sunday, Washington State Department of Health spokesman Bob James said.
Investigators will take another round of tests on Sunday to measure against earlier findings, and only then will they be able to tell whether the island’s water supply is safe enough to use again, James said. Since testing for the bacteria takes 18-24 hours, the ban will almost certainly last through the weekend, he said.
Seattle Public Utilities, which provides water to the island, is inspecting system facilities, flushing water mains in possible problem areas on the island and making sure chlorine levels are adequate. No E. coli has been found in the drinking water of any other part of the water system, officials said.