UW-Manitowoc keeps an eye on the summer party pooper in Lake Michigan

 By Derek Kohlbeck 

Ahh, spring is finally here and summer can’t be too far away. Are you already dreaming of lazy days on the beach, Jet Skiing, swimming or fishing on Lake Michigan? Don’t be alarmed to find a red octagonal sign staked in the sand at the beach this summer, a sign informing you that it might be safer to leave your swimsuits at home.  

Yet, E.coli is simply a type of bacteria that resides in warm-blooded animal intestines. In fact, E. coli is not always such a bad thing. It is a natural part of the digestive process in the large intestines of many birds and mammals, including humans.  

As Professor Hein explained, “We have a vast array of knowledge concerning E. coli, including its entire genome sequence.”  

It is one of the most widely examined microorganisms and can be easily developed in a petri dish. Under a microscope, E. coli is approximately one micrometer in diameter and has a rod-like shape (bacillus).  

There are several strains of E. coli. One of the most well-known E. coli strains seen in the news, a strain that causes food poisoning, is named 0157:H7. In the environment, E. coli is not a major threat. Rather, its presence is an indicator of pollution in terms of fecal contamination.  

As Professor Hein noted, “E. coli may indicate the presence of other micro-organisms and viruses that could cause disease.” When E. coli is present in a healthy lake, this is usually a sign of pollution, a possible risk for aquatic organisms as well as swimmers.  

This project monitoring the waters is a statewide effort coordinated by UW-Oshkosh and comprised of several universities and municipalities along the lake. Other partners include the Manitowoc County Department of Public Health, Manitowoc County Department of Soil and Water Conservation, City of Manitowoc, City of Two Rivers, Village of Cleveland, an advocacy group called Centerville CARES, and the Wisconsin DNR.   

In 2000 Congress passed the Beaches Environmental Assessment and Coastal Health (BEACH) Act. According to the U.S. Environmental Protection Agency, “The Act established uniform criteria for testing, monitoring, and notifying public users of possible coastal recreation water problems.” Although federal legislation approved the BEACH Act for the Great Lakes in 2000, it wasn’t until 2003 that Wisconsin became the first state to enact BEACH.  

In the summer of 2007, UW-Oshkosh asked UW-Manitowoc to manage the task of monitoring the waters of Manitowoc and Kewaunee counties. So, for the past two years, UW-Manitowoc has assisted Oshkosh in testing Lake Michigan’s beach water. UW-Manitowoc is particularly well-equipped to analyze the water due to the local knowledge and the school’s laboratory.  

For UW-Oshkosh, “Working with our group is an advantage over contracting to private labs because we are available 24-7 to perform needed experiments and monitoring,” Hein noted. Water samples are gathered from seven different sites in Manitowoc County: Point Beach, Neshotah Park, Memorial Drive North, Memorial Drive South, Red Arrow, Hika, and Fischer Creek.  

Source tracking – that is finding the direct cause of the E. coli – was conducted by the UW-Manitowoc Biology Department at Point Beach and Neshotah in 2007, and at Point Creek and Fisher Creek in 2008. The results led to 33 beach closures in 2007 and 24 closures in 2008. The researchers tested only six beaches in 2008 instead of seven so the lower number of closures in 2008 was primarily due to fewer sites tested.

Each year the ongoing project has included student participation. In the first two years, Professors Hein and Abler worked with UW-Manitowoc students Lindsey Lorenz and Kimberly Busse; however, low funding for the project has allowed them to employ only one student for the summer of 2009 – microbiology major Anna Hubbartt.  Hubbartt’s fascination for microbiology originated with her mother, who has a degree in the field.  

“It has always been my dream to work for the Centers for Disease Control,” Hubbart said, adding, “I am extremely grateful because it is really rare that a freshman in college gets a chance to do something as cool as this.”  

In examining the water quality of the lake, student workers begin by collecting 100 ml samples from the lake. Back in the laboratory, they apply a reagent – a substance that causes a chemical reaction – to the water. This reagent is called Coli-leret, and it has a florescent tag that will confirm the development of coliform bacteria and E. coli. The water is placed into the various compartments of a tray and when the reagent is added to the water, a chemical reaction takes place. If a yellow color appears in any of the compartments, this suggests the presence of coliform. If the coliform glows a florescent blue under a UV light, that indicates E-coli.  

“Concentrations are measured by a most probable number analysis,” Hein explained.   

This technique analysis helps them estimate the number of bacteria colonies existing in the water. In the environment E-coli is mostly a short-lived organism. The lake’s natural currents and wind-driven waves help disperse the bacterium.  

There are other factors that cause the tide water to become stagnant. Cladophora, which are large mats of algae, buffer the natural flow of the water. Also manmade outcropping aid algae growth and affect the tide.       

In 2007 Abler and Hein collected data on the types of E. coli present in Lake Michigan and found closer matches to avian DNA than to any other source. This would indicate that the E. coli contamination on the beaches might be the result of bird feces in the water. But, don’t hold the geese and gulls accountable just yet.   

Although the 2007 data revealed closer matches to avian DNA than any other source, birds are not the ultimate source of contamination. As Professor Abler explained, “the evidence we have accumulated in 2007 and 2008 indicated that in Manitowoc County, it is extremely likely that there are multiple sources of contamination – not a single smoking gun.”  

Still, Abler and Hein have not yet been able to pinpoint the cause due to the vast number of possible other contaminating sources that are individually tested. In 2008, the Biology Department was granted funding to test for cattle DNA, and expand their library of identified DNA samples. Since Manitowoc is an agricultural county, the attention has shifted toward cattle as being one of the major contributors of E. coli pollution in Lake Michigan.  

Professor Abler stated, “We look forward to gathering more data that will help beach managers understand the complex dynamics involved in beach contamination.”  

For now, beach goers simply need to heed the signs posted on the beach.