Water samples collected by Friends of the Mad River (FMR) volunteers on Monday morning August 22nd show variable swimming conditions throughout the watershed, with fifteen of thirty-six sites tested exceeding Vermont’s water quality standard for E.coli in recreational water (no more than 77 colonies of E.coli bacteria per 100mL water).
The state water quality standard for recreational waters measures E. coli bacteria, an indicator of pollution from human or animal waste. High E.coli levels can pose a danger to swimmers since the presence of fecal borne pathogens is likely. E.coli levels tend to rise when rain washes pollutants into the river.
Rain showers and thunderstorms hit the Mad River Valley on Sunday; 0.4 inches of precipitation was recorded at the USGS gauge in Moretown. The flow of the Mad River as measured at the gauge peaked near 180 cubic feet per second (cfs) around 9:00am Monday morning; volunteers collected water samples between 7am and 10am. The flow at the time of sampling was a bit higher than the median for this date (50 cfs).
This was the last sampling date for the 2011 Mad River Watch program—the 26<sup>th</sup> season of the program. In 2011, there were 67 samples that exceeded Vermont’s standard for E.coli. There were 89 exceedences in 2010, 65 in 2009, and 14 in 2008.
For more information about E. coli and the Mad River Watch program, or to report a river-related illness call 496-9127, or visit www.FriendsoftheMadRiver.org. Thanks to this week’s Mad River Watch volunteers; samplers this week included: Mike Ware, Susy Deane, Fran & Gary Plewak, Ry Young and Kate Sudhoff. Thanks also to Cyndee Button for her great volunteer work as lab coordinator.