DRWA monitors fecal coliform bacteria at popular recreational sites throughout the watershed. Fecal Coliforms are bacteria that live in the intestines of warm-blooded animals. They are not necessarily harmful themselves, but they may indicate the presence of viruses and pathogens that are harmful to humans (generally causing intestinal ailments). We report results in number of fecal coliform colonies per 100 milliliters.
The State Water Quality Standards for recreation are:
|
River
Use
|
Standard
if 5 or more
samples at site |
Standard
if fewer
than 5 samples at site |
| Primary Contact Recreation (Swimming, Fishing) |
less than 200 colonies
per 100ml |
less
than 400 colonies
per 100ml |
| Secondary Contact Recreation (Boating) |
les
than 1000 colonies
per 100ml |
less
than 2000 colonies
per 100ml |
Because we only take one sample per site per collection, we compare our results to the right column in the table above
| Deerfield River Fecal Coliforms 2001 | ||||||
| (Number of colonies per 100 ml) | ||||||
| Site | 3-Jun-01 | 17-Jun-01 | 1-Jul-01 | 15-Jul-01 | 5-Aug-01 | 19-Aug-01 |
| Cold River | 17 | 123 | 200 | LE | ||
| Deerfield Academy | 25 | NS | 114 | LE | ||
| South River Confluence | 800 | 69 | 690 | LE | ||
| Stillwater | 32 | 240 | 110 | LE | ||
| Potholes | 104 | 600 | 220 | LE | ||
| Wilcox Hollow | 210 | 200 | 158 | LE | ||
| Zoar Gap | 0 | 12 | NS | LE | ||
| Green River Covered Bridge | 140 | 106 | 48 | LE | ||
| Sunburn Beach | 330 | 405 | 380 | LE | ||
| North River above BBA | 773 | 185 | 400 | LE | ||
| West Branch Deerfield River | NS | NS | 142 | LE | ||
| NS=Not Sampled LE=Lab Error | ||||||
| Red: violates swimming standards | ||||||
| Orange: violates swimming and boating standards | ||||||
Our first testing this year (June 3) occurred after a big storm and we found fecal coliforms at all sites except Zoar Gap. Most counts were within acceptable limits (below 400), but the North River above BBA in colrain and the confluence of the South River violated State Standards for swimming and fishing.
The June 17 collection shows how conditions change with weather: A storm moved through the watershed during sampling, so that early collectors took their samples a few minutes after it started raining, and the late collectors were definitely sampling the "first flush" of the storm in the river. Note the high reading at the Potholes, probably the most popular swimming hole in the watershed: this peak likely results from surafce runoff to the storm sewers in Shelburne Falls which empty into the river just upstream.
On July 1 we sampled 12 hours after a thunderstorm, and a few sites had high bacteria counts again. At his point it looks as if our marginal sites may be the North River above BBA and the South River confluence, while the cleanest spots are Zoar Gap and the Cold and Green Rivers.
Our incubator malfunctioned on July 1, "frying" our bacteria plates, so we can't report data for that date.
We can see that different weather patterns result in varying levels of bacteria throughout the watershed, pointing to the need to continue sampling until we have a respectable collection of data.
 |
The
DRWA Water Quality Monitoring Program is funded in part by the Massachusetts
Environmental Trust.
|
This
web site made possible in part by the Valley Charitable Trust Fund administered
by Fleet National Bank, and by the Community Foundation for Western Massachusetts
|