The swimming beach at Island Lake County Park has been reopened June 13, as the Kitsap Public Health District has announced that water samples show bacteria has returned to safer levels.

KPHD initially closed the swimming beach June 11 due to high levels of E. coli bacteria in the water.

The closure level for E. coli is a geometric mean value of 100 MPN/100 mL. For samples taken June 10 at the beach, the GMV was 218 MPN/100 mL. MPN/100mL is a unit of measure and stands for the “most probable number” of bacterial colonies that grow in a 100 milliliter sample, per KPHD.

No illnesses were reported to the health district.

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, KPHD says.