Signs at Darling, Backbone, Geode, Prairie Rose and Beeds Lake state parks will warn swimmers to be cautious because of high bacterial readings. That means organisms that could sicken people probably were present Monday, the most recent readings available. We have never had a documented serious illness at any of our beaches. The state checks 35 beaches at least once a week. Signs at each state-park beach tell swimmers not to swallow the water, especially after rainfall.
Rain can wash animal wastes and sewage, along with the disease-causing organisms, into the lakes.
The signs also ask people to keep soiled diapers out of the lakes. Swallowing the pathogens can cause anything from minor stomachaches to severe intestinal problems. Skin rashes and eye, ear and nose infections are possible. In highly polluted water, more serious illnesses such as hepatitis can occur, the EPA says. Park administrators said they'll wait until more weekly fecal-bacteria tests are done before deciding whether to close beaches.