CLICK HERE for the Water Quality E. coli Monitoring Report for Clark Lake
More Information regarding E.Coli:
The “Advisory” standard of 235 CFU/100 mL (E. coli in water) was adopted based upon data from three USEPA studies conducted in the late 1970s (2-4). These studies indicate that E. coli and/or Enterococci are the best bacterial indicators to assess the risk of acquiring a gastrointestinal illness as a result of using recreational waters. These levels are the original recommendation of USEPA and they were reaffirmed in a revisiting of the issue in 2002 (1).
Additional epidemiological studies are set to take place during the BEACH program and should be completed by 2006. These studies are detailed in the following reports and are available free in *.*.pdf format from the USEPA website.
The epidemiological studies indicated that a level of 235 CFU of E. coli/100 mL of recreational water is approximately equal to 8 cases of gastrointestinal illness per 1000 recreational water users.
The “Closure” level of 1000 CFU E. coli/100 mL was adopted by the WDNR based upon data from the studies mentioned above and represent a risk of approximately 14 cases of gastrointestinal illness per 1000 recreational water users.