Is the water safe? That’s a question many swimmers might be asking as they contemplate a dip this Fourth of July. The state conducts weekly water tests at all state beaches. When high levels of bacteria are found, the beach can be closed or a warning posted. Iowa Department of Natural Resources spokesman Steve Pennington says the testing shouldn’t discourage anyone from swimming at state beaches.He says the testing is purely precautionary, and there are no known cases of anyone getting seriously ill from swimming at state beaches. Pennington says the water tests don’t actually look for the bacteria that cause illness. The instead test for three forms of bacteria that show up along with the other bacteria.They’re called indicator bacteria because they indicate the possible presence of the bacteria that cause illness. Pennington says there are some precautions you can take when swimming in any natural body of water; don’t swim immediately after it rains, don’t swallow the water, and take a shower after swimming.