go to the MRW results for 7.26.10
Mad River Watch volunteers collected
water samples throughout the watershed on Monday morning July 26th. Results show there were favorable
swimming conditions at some locations, while at others E.coli levels were above the state water
quality standard. The state water quality standard for recreational waters
measures E. coli
bacteria, an indicator of pollution from human or animal waste and the potential
presence of disease causing organisms. Eight of thirty-six sites tested were
found to be in violation of the standard at the time of sampling. Sites in
violation of water quality standards were located in Warren, Waitsfield and
Moretown and included: Warren
Village, Couples Club, Waitsfield Covered Bridge, Meadow Road bridge, Moretown
Village Swim Access, and Ward’s swimhole.
Heavy rains brought the river up to
approximately 3,000 cubic feet per second (cfs) on Wednesday July 21st, and
some scattered rain also fell on Sunday.
At the time of sampling on Monday morning, the volume of water flowing
in the Mad River (as measured at the USGS gage in Moretown) had declined to
approximately 170 cfs. This level
is higher than the median flow for this date (according to 80+ years of data;
about 60 cfs), thus the flow in the river was high and declining at the time of
sampling. Swimmers are more likely
to encounter safer conditions in declining and low flows since pollutants are
not being actively washed into the river by rain; rain that turns the Mad River
brown also brings E.coli levels up and increases the risk to swimmers of contracting a water
Since the heavy rain fell on July 21st,
the Mad River has appeared especially cloudy; the river did not return to it’s
usual clear appearance even after the high water subsided as typically
happens. Upon investigation, it
was discovered that several natural clay deposits along Stetson and Lincoln
Brooks in Warren were heavily eroded during the storm. This problem may have been exacerbated
due to several plugged and failed culverts along Stetson Hollow road. The river may continue to appear cloudy
until the erosion of natural clay deposits subsides.
For more information about E.
coli and the Mad
River Watch program, or to report a river-related illness call Friends of the
Mad Rive at 496-9127. Many thanks
to lab coordinator Cyndee Button and to this week’s Mad River Watch volunteers:
Elizabeth Walker, Michael Ware, Kate Sudhoff, Fran & Gary Plewak, Patti
Greene-Swift and Susy Deane.