Advisory issued for Island Lake County Park

Avoid contact with water in the swimming area until further notice.

Kitsap Public Health District has issued an advisory at Island Lake County Park swimming beach due to high levels of E. coli bacteria in the water. We will monitor water quality at the beach and lift the advisory when bacteria return to a safer level.

Because there is an increased risk of getting sick, please avoid all contact with the water at the swimming area. This means no swimming, wading, or types of water play where water could be swallowed or get into your mouth, nose, or eyes. The risk of illness is greatest for young children, older adults, or anyone with a weakened immune system.

No illnesses have been reported to the Health District at this time.

Swimming beach monitoring

We monitor popular swimming beaches for bacteria during the summer months. We also check for toxic cyanobacteria (blue-green algae) and other safety concerns. If people or animals become sick after being in the water, or if you see an algae bloom or large numbers of dead fish, please report it online or by calling 360-728-2235. We will investigate and take action if necessary.

High levels of bacteria can be caused by wildlife and pets in the water, people swimming when they are sick with diarrhea, crowded swimming areas, infants swimming without swim diapers, or people entering the water without showering. 

Sampling results

The advisory level for E. coli is when the geometric mean value (GMV) is over 100 MPN/100 mL.

For samples taken June 16, 2026 at Island Lake County Park swimming beach, the GMV was 101.6 MPN/100 mL.

Resources

• Water Advisories | Kitsap Public Health

• Swimming Beach Monitoring | Kitsap Public Health

• Sign up for email and text alerts | Kitsap Public Health

• Recreational Water Illness | WA Dept. of Health