After what seemed to be an endlessly cold spring, we are finally getting our first taste of summer weather. For many, summer in Dane County means time at the beach. Madison area beaches open for the season on Saturday, May 28th – Memorial Day weekend.

To protect the health and safety of residents, the Public Health Madison and Dane County (PHMDC) Laboratory monitors most public beaches in Dane County. During the swimming season laboratory staff conduct water quality testing at 13 Madison beaches, UW beaches and two Dane County beaches. All other Dane County Beaches are monitored by the Wisconsin Department of Natural Resources (DNR) or by local municipalities. If a water test shows concerning results, the beach will close until levels of bacteria or blue-green algae return to normal.

In Dane County, a common health and safety challenge at area beaches are blooms of blue – green algae – which are not actually algae, but a type of photosynthetic (sunlight-loving) bacteria known as cyanobacteria. Blue-green algae blooms occur naturally in lakes, streams and ponds and some varieties are capable of producing toxins. When water temperature, wind and wave patterns combine with high nutrient levels in the water, they can grow into ugly mats that are most often blue-green in color, but can also be reddish-purple, or brown.

The appearance and smell provide a built-in warning to keep people away. This is a good thing, since exposure to its toxins can produce a range of reactions, from rashes and lip blistering to sore throats, headaches, muscular and joint pain as well as asthmatic and gastro-intestinal problems.

When a bloom does appear, PHMDC will close the beach for all swimming. Since winds and currents can make some blooms disappear as quickly as they appear, some of these closings may not be for very long. If you see a bloom, the best and safest response is to keep yourself, your children, and your pets out of the water. Dogs exposed to blue-green algae can suffer near fatal or fatal consequences.

According to PHMDC´s Laboratory Manager, Kirsti Sorsa, “PHMDC will also close a beach if the water tests positive for E-coli contamination which is frequently caused by storm water runoff rich in contaminants such as goose and pet waste. This kind of bacterial contamination tends to spike after heavy rains. Since most beach closings are due to weather conditions, it is impossible to predict how many beaches might be closed at any given time. During some summer seasons we might see very few closings and during others we may see several beaches being closed in just one day,” says Sorsa.

Reports of beach closings and up-to-date beach conditions including the results of lab testing are available at the PHMDC website at www.publichealthmdc.com/beaches.

The Public Health lab also tests the water of all public and commercial swimming pools in Dane County.

If you believe you have been exposed to blue-green algae, contact your health care provider right away. You should also report this to a lifeguard and call Public Health at (608) 266-4821.