Water Quality Results

Again in 2018, the Town of Colchester is testing the water along its 27 miles of shoreline in Malletts Bay and Lake Champlain. Our goal is to keep beach goers informed of water safety conditions and to identify possible problem sources of harmful bacteria.

This year's water quality results

Sampling Locations Map

Archival Test Data is now available for 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, and 2017 .

Call 264.5628 to report any Water Quality or Storm Water issues. Have Swimmers' Itch? Learn more about that here

Twelve water samples from 9 different sites are tested twice a week for the bacteria Escherichia coli (E. Coli). E. Coli is a very effective indicator for the possible presence of more harmful bacteria that can cause human health problems such as gastrointestinal dysfunction (gastroenteritis).

SINCE 2013: The Vermont State Health Department now recommends not swimming in water where E. Coli levels are higher than 235 colony forming units (CFU) per 100 milliliters of water. Vermont was one of the most stringent states in this regard, maintaining a level of 77 CFU while the Federal level was at 125 CFU. In the spring of 2012, the Federal level (determined by the EPA) was raised to 235 for a single sample (although most of their research is looking at data over a 30 to 90 day period and not a single occurence. Vermont decided to follow suite. For the general areas of the lake along Colchester's shores, when water samples come back with E. Coli levels higher than 235 CFU/100mL, those readings will appear in RED.

The 9 sites tested on a regular basis this year are the same ones used in the past few years and allow us to maintain consistency in our data collection. Other sites may be added for short-term testing due to specific conditions.

For Bayside Beach and Rossetti Natural Area, multiple samples are taken each testing day. If two or more of the samples have unsafe E. Coli levels, the affected beach will have signs erected warning of these high levels. The signs will remain until new tests come back with safe E. Coli counts. We do not close our beaches, but do inform the public of high E.Coli readings in this manner.

AS A GENERAL RULE: Swimmers should always stay clear of streams, and where streams and storm drains flow into the lake. A distance of at least 100 feet from stream and drain outflows is advised. Swimmers should also avoid swimming after rainfall for at least 1 - 2 days.

If you have any questions or comments, please email Steffen Parker, Water Quality Coordinator at sparker@colchestervt.gov or call the Stormwater Hotline @ 264.5628