Is It Clean ?

The Connecticut River and its tributaries are much, much cleaner than they were ten, twenty, or thirty years ago. Citizens, businesses, cities and towns have spent hundreds of millions of dollars to clean up our waters, but unfortunately there are still times when it isn't the best idea to go swimming or boating. The map on this page identifes sites recently sampled for Escheria coli bacteria levels, also called E. coli bacteria.  Click on the blue, yellow, or red map icons to learn more  about bacteria levels at that site and site access information, or use the SEARCH at the bottom of the page and search by site name or town.

In addition to the bacteria level for each sampling event, it is noted whether or not it was a wet weather event. Wet weather is defined as any day in which >0.1" of rain fell within the 48 hours preceeding sample collection. Bacteria levels are typically elevated during wet weather events.

BLUE Clean for swimming and boating <235 cfu/100 ml
YELLOW Clean for boating only 235 - 575 cfu/100 ml
RED Not clean for swimming or boating >575 cfu/100 ml

Certain bacteria, viruses and other microorganisms can make you sick with stomach pains, rashes, breathing problems, diarrhea, or other intestinal problems. We test for the amount of E. coli bacteria in the water which is an indicator for all types of other "bad guys". These numbers represent a risk threshold, or the chance that you might get sick if you came in contact with water with a concentration of these bacteria. If a person follows the guidance used at theis website, they will have a less than 1% chance of contracting a water-borne disease. For more detailed information about bacteria standards for primary and secondary contact click here.

Connecticut River Bacteria Data 2008-2011

Connecticut River Bacteria Data 2012

Connecticut River Bacteria Monitoring Video

Field Guide to Visual Water Quality Indicators



Red Not Clean for Boating or Swimming
Yellow Clean for Boating
Blue Clean for Boating and Swimming