Pollution released into beach waters from sources like agricultural runoff or untreated sewage can expose swimmers to harmful microorganisms called "pathogens." These pathogens can be present at or near the site where polluted discharges enter the water. Pollution can also be created by people who leave trash or animal waste at beaches.

E. coli is a common bacteria found in human and animal digestive systems. The presence of E. coli is used as an "indicator" by beach managers when testing recreational water, and is used to monitor for the possible presence of other more harmful microbes, such as Cryptosporidium, Giardia, Shigella, and Norovirus.

In the event that beaches are closed or advisories are posted, it is most often because water samples indicate that harmful bacteria, viruses, protozoa, or parasites are likely present in the water.

EPA supports local and state efforts to protect and clean up beaches. EPA also supports monitoring and notification efforts by local beach programs.

Learn more about E.coli at beaches by exploring the links below.