The state Health Department posted signs Tuesday afternoon warning the public of high bacteria levels at Punaluu Beach Park on Oahu.

During routine monitoring, the department’s clean water branch found enterococci levels of 222 per 100 milliliters, exceeding the threshold of 130 per 100 milliliters.

Testing for enterococci indicates that potentially harmful microorganisms such as bacteria, viruses, protozoa or parasites may be present in the water, according to the state Health Department. Swimming at beaches with pollution in the water may make people ill, particularly children, the elderly and people with weakened immune systems.

Fortunately, while swimming-related illnesses can be unpleasant, they are usually not very serious and require little or no treatment, get better quickly upon treatment and have no long-term health effects.

The signs will remain posted until water sample results no longer exceed the threshold level. Updates are available at this link.