As advised by the Department of Health, King County Water District #54 (KWCD) on Saturday, June 17, 2023 issued a ‘Boil Water Advisory‘ for the cities of Des Moines and Normandy Park.

The advisory covers a large part of north Des Moines’ Marina and North Hill Districts.

KCWD #54 said that a recent routine test came back positive for E. coli, but subsequent re-tests came back coliform present, E. coli absent. These bacteria can make you sick and are a particular concern for people with weakened immune systems.  

The District began chlorination on Saturday, June 17, 2023 and will “continue as necessary.”

“We are committed to the health and safety of our residents,” KCWD said in a statement. “In an abundance of caution, water used for drinking, making ice, brushing teeth, washing dishes, and food preparation should be boiled. Boiling kills bacteria and other organism in the water.”

Here’s more from KWCD #54:

Following Department of Health guidelines and with an abundance of caution, we are issuing a boil water advisory.  

DO NOT DRINK THE WATER WITHOUT BOILING IT FIRST. Bring all water to a rolling boil for 1 minute, and let it cool before using.  Boiled or purchased bottled water should be used for drinking, making ice, brushing teeth, washing dishes, and food preparation until further notice. Boiling kills bacteria and other organisms in the water.

The presence of E. coli indicates the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, some of the elderly, and people with severely compromised immune systems. The symptoms above are not caused only by organisms in drinking water. If you experience any of these symptoms and they persist, you may want to seek medical advice.  People at increased risk should seek advice about drinking water from their health care provider.

What happened?  What is the suspected source of contamination?

The KCWD #54 does weekly water samples throughout the district. Only one sample came back E. coli present. Follow-up samples were submitted for testing and they came back coliform present, E. coli absent. Coliform bacteria are commonly found in the environment, such as soil and vegetation. We suspect the positive water samples were the result of a recent water main break, which dislodged mineral buildup that can harbor bacteria. The District will test more frequently until the issue is resolved. 

The following is being done to correct the problem: 

KCWD #54 commenced chlorination in the water system on Saturday June 17, 2023 and will continue as needed. Chlorination is used to sanitize the water system, but it has effects that some customers find unpleasant. Minerals, such as iron and manganese, are present in the water at all times and build up inside the pipes. Adding chlorine literally cleans off the mineral build-up.  This may cause some customers to experience cloudy or brown looking water. The District will aggressively flush the system to reduce these effects. We are also performing a Level 2 assessment required by the Department of Health.  

KCWD #54 has consulted with the Washington State Department of Health about this incident.  We will notify you when you no longer need to boil the water.  

For more information contact Eric Clarke at (206) 878-7210 or the office at 922 So 219th St, Des Moines, WA 98198.


The map below shows KWCD boundaries: