Low E. coli Levels Found At Lake Superior Beaches
Ann Arbor, Mich. — Cold water and E. coli do mix. While many Great Lakes' beaches have had problems with closures from bacterial contamination, it was long assumed that Lake Superior was too cold to have problems with microbes. This is not the case according to researchers studying lake contaminations.
Reynée Sampson and fellow researchers monitored 27 Lake Superior beaches in summer 2003 and found that E. coli levels (an indicator of fecal contamination in water) exceeded beach standards in about 1% of the samples taken. There was no connection between lake temperature and higher E. coli amounts. "In fact, our highest E. coli reading came when the water temperature was about 40o F," states Sampson, a graduate student at University of Wisconsin-Oshkosh.
Where the water sample is taken does affect the E. coli concentration, however, with shallow water having consistently greater levels of contamination than deeper water. Likewise, variation along the beachfront can be extensive, prompting Sampson to recommend multiple or composite samples to be taken at any given beach to more accurately reflect the true level of contamination.
Original Publication Information
Results of this study "E. coli at Lake Superior Recreational Beaches" are reported by Reynée Sampson, Sarah Swiatnicki, Colleen McDermott and Gregory Kleinheinz in the latest issue (Volume 31, No. 1, pp. 116-121) of the Journal of Great Lakes Research, published by the International Association for Great Lakes Research, 2005.
Contacts
For more information about the study, contact Gregory Kleinheinz, Department of Biology & Microbiology, Halsey Science Center, University of Wisconsin-Oshkosh, Oshkosh, WI 54901; kleinhei@uwosh.edu; (905) 336-4865.
For information about the Journal of Great Lakes Research, contact Marlene Evans, Editor, National Water Research Institute, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada; marlene.evans@ec.gc.ca; (306) 975-5310.
Since 1967, IAGLR has served as the focal point for compiling and disseminating multidisciplinary knowledge on North America's Laurentian Great Lakes and other large lakes of the world and their watersheds. In part, IAGLR communicates this knowledge through publication of the Journal of Great Lakes Research, available to members in print and electronic form. A searchable archive of the journal is available online and includes the abstracts of articles from the journal's inception in 1975 through the most recent issue. In addition, complete articles are available to members who have signed up for an electronic subscription.
