Wisconsin Beach Water Quality

Advisories in Wisconsin are issued and lifted by Wisconsin Department of Natural Resources and the local health departments that work with it, often within a couple of days, so the current answer is theirs: Wisconsin DNR beaches and the Wisconsin Beach Health database publishes current and historical E. coli monitoring data and beach advisories. This page gives you what Wisconsin monitors, how its programme compares with the rest of the country, and the link to that page. EPA puts the division plainly: "States, Tribes, territories and local governments decide whether to open or close a beach."

At Wisconsin DNR beaches and the Wisconsin Beach Health database, which publishes current and historical E. coli monitoring data and beach advisories. Link verified 2026-09-02. The sign at the beach entrance outranks any website, including that one, because it was put there by someone who looked at that specific water. EPA's own advice: "Be aware of any signs indicating the beach is closed or the water is not safe because of bacteria, riptides or other hazards. In areas that are not monitored regularly, choose swimming sites in less developed areas with good water circulation, such as beaches at the ocean. Avoid swimming at beaches where you can see discharge pipes or at urban beaches after a heavy rainfall."

In EPA's 2025 swimming season report, Wisconsin had 195 BEACH Act beaches. 117 of them were program beaches, meaning a programme reports notification actions to EPA at least once a year, and 117 of those were sampled for bacteria at least once during the season. Every program beach in the state was sampled. A further 78 beaches EPA counts sit outside the programme entirely. Those are EPA's counts.

Fecal indicator bacteria, which are not themselves the thing that makes people ill. They are counted because they are cheap and fast to measure and they track the presence of sewage and animal waste. Marine programmes generally count enterococci and Great Lakes programmes generally count Escherichia coli. EPA describes what a result actually implies: "In the event that beaches are closed or advisories are posted, it is most often because water samples for certain bacteria indicate that harmful bacteria, viruses, protozoa, or parasites are likely present in the waters." Nothing in a bacteria count says anything about chemicals, jellyfish, rip currents or algal toxins, each of which is a separate programme.

Wisconsin Department of Natural Resources publishes it as Memorial Day weekend through Labor Day weekend. In its own words: "The beach monitoring season runs from Memorial Day weekend through Labor Day weekend each year." Outside that window most beaches in the state are not being sampled at all, so the absence of an advisory in April or November usually means nobody has looked rather than that the water was tested and passed.

No, and this is the single most important thing on this page. An absent advisory can mean the water was sampled and the result was under the state threshold, or that the beach is one of the 0 program beaches in Wisconsin that nobody samples, or that the sample was taken before the rain that arrived last night. Results take about a day to come back from the lab, so even a fresh posting describes yesterday's water. EPA links digging in sand to illness too: "The EPA has linked digging in beach sand to an increased risk of gastrointestinal illness."

At Wisconsin DNR beaches and the Wisconsin Beach Health database, published by Wisconsin Department of Natural Resources and linked above. Advisories are lifted as soon as a follow up sample clears, often within a day or two, which is why the agency's own page is the place to read them rather than any copy; EPA says the same about its own national database: "States, territories and Tribes receiving beach grants submit information on beach monitoring and closures and advisories to the EPA, but they are only required to submit that information once a year, although some report more frequently. Therefore, BEACON has information about the previous year and earlier, but it does not have current information about advisories or closings." This page carries the durable half: what is monitored, by whom, and how much of the coast that covers.

CDC: "You can get swimming-related illnesses if you swallow, have contact with, or breathe in mists of water contaminated with germs. The most common swimming-related illnesses are diarrhea, skin rashes, swimmer’s ear, pneumonia or flu-like illness, and irritation of the eyes or respiratory tract." EPA names the groups most affected: "Children, the elderly and people with weakened immune systems are the most likely populations to develop illnesses or infections after coming into contact with polluted water, usually while swimming." The exposure route that matters most is swallowing water, which is why EPA's practical advice is about your head rather than your skin: "When waterborne pathogens are present, most swimmers are exposed when they swallow the water. You will be less likely to get sick if you wade or swim without putting your head under water." That is the two federal agencies quoted directly.

From EPA's BEACON Dynamic National Report, the public face of the database that BEACH Act states report into. We read the 2025 swimming season table as it stood on September 02, 2026 and stored the counts unchanged; a US Government work in the public domain. Wisconsin is one of 11 states where most beaches EPA counts sit outside the reporting programme. Every count on this page is EPA's.