(KMZA)--Health alerts have been issued for three lakes in Nebraska due to the presence of toxic blue-green algae--including Iron Horse Trail Lake in Pawnee County.

The Nebraska Department of Environment and Energy made the announcement Friday.

Signs will be posted to advise the public to use caution. Designated swimming beaches are closed during the alert.

The state agency says recreational boating and fishing is allowed but the public should use caution and avoid exposure to the water, particularly avoiding any activity that could lead to swallowing the water.

Pets should not get in the water or drink from the lake. People can still use the public areas for camping, picnics, and other outdoor activities.