It may not be quite warm enough yet to take a plunge in an Iowa lake, but the Iowa Department of Natural Resources is once against testing the water at 34 state beaches. The D-N-R’s Mary Skopec says they’re testing for high levels of bacteria that could cause health problems. She says over time they’ve changed what they’re looking for to now look at e-coli bacteria more than coliform bacteria, due to a change in the state water quality standard. Skopec says they’ve also changed the rules that used to close beaches when high levels of bacteria were found in the tests. She says they instead post signs that say swimming is not recommended. She says that’s partly based on whether or not there’s human sewage poured into the water. This is the fourth year of the testing, and she says they’re starting to build a database. She says so far they’ve found that 97-percent of the time the beaches are within the E-P-A guidelines. She says that’s surprising with the large number of livestock in the state. Skopec says they’ve also learned that rain can make a big impact on the water. She says bacteria levels tend to increase after a heavy rainfall and it’s best to not be in the water until a few warm days help take care of the bacteria. While the testing just recently got underway, there’s already a swimming advisory posted for the beach at Backbone State Park in Delaware County and the Lake Darling State Park in Washington County for high levels of bacteria.