Didymo found in White River

Didymo found in White River

July 16, 2007

An invasive algae, called “didymo” or “rock snot,” has been found on the White River. According to state biologists, the didymo algae has been confirmed on the mainstem between Stony Brook in Stockbridge and Cleveland Brook in Bethel. The White River Partnership is working with the state biologists and a number of other organizations, including Trout Unlimited and the Connecticut River Watershed Council, to educate the public about stopping the spread of the didymo algae within and beyond the White River watershed.

What is didymo?

Didymo does not present a health hazard to humans. However it can impact our native fish populations, like trout and salmon. The algae attaches itself to the gravel and rocks at the bottom of the river bed. When the algae blooms, it forms massive mats that coat the gravel and rocks. These mats crowd out the native organisms in streams and rivers that fish eat, which may result in their decline.

The algae is easy to spread. Each cell is very small, so they absorb easily into clothing, wading boots, and sandals as well as stick to hard surfaces like tubes, kayaks, and fishing gear. If these items do not dry completely, the algae can be spread the next time the item is used.


Although there is no known method of removing or killing the algae once it is in the river, WE CAN STOP IT FROM SPREADING! Simply soak all clothing, wading boots, sandals, etc in hot, soapy water for 30 minutes. Wash all hard surfaces like tubes, kayaks, and fishing gear with hot, soapy water as well. A 5{db44c3d5e5b2521111bb9179cb40e40c4d2777ab57a0c9e12ea819349259de2f} detergent solution is effective = 3/4 cups of any detergent (dish soap, antiseptic hand soap, or laundry detergent) per gallon of hot tap water will kill the algae.

We need your help!

The state biologists are developing signs to educate the public about how to stop the spread of didymo. White River Partnership and Trout Unlimited volunteers will be posting these signs along the mainstem of the White River over the next week. If you would like to help, please contact Mary Russ at 802-767-4600 for more information.