The U.S. Army Corps of Engineers, and its Engineer Research and Development Center’s (ERDC) Aquatic Plant Control Research Program, will lead a demonstration project to determine the effectiveness of herbicides registered for aquatic use by the U.S. Environmental Protection Agency to safely reduce and control the spread of the CT River hydrilla. The project will investigate hydrilla’s growth patterns, water exchange dynamics in the CT River, and evaluate herbicide efficacy in laboratory conditions in 2023 to guide operational scale field demonstrations of herbicide efficacy in 2024.
How will hydrilla be treated?
The U.S. Army Corps of Engineers will be developing site-specific treatment plans for aquatic herbicides use in the CT River in the summer of 2024. There are several safe, well understood, and effective herbicides that are being considered for use. Selected herbicides will be added to the website once they have been chosen.
Post application monitoring surveys will be conducted in fall 2024 to assess the condition of the hydrilla as well as non-target impacts.
Will the hydrilla treatment impact recreation and fishing in the Connecticut River?
The hydrilla treatment should have minimal-to-no impact to recreation in the CT River. Other than a few morning hours when contractors are on-site carrying out the treatment, where some restricted public access may be needed, no long-term closures or restricted access is currently anticipated with this work.
The exact locations of where the hydrilla treatment would occur has not been selected yet, but the eight sites being considered are Keeney Cove, Mattabesset River, Portland Boat Works, Dart Island State Park, Chapman Pond, Chester Boat Basin, Selden Cove, and Deep River.
Regarding fishing, the treatment is expected to have minimal to no effects on fishing or to fishing access. Coves are popular fishing spots and the coves where work may take place will still be available for fishing outside of the morning hours when contractors are on site carrying out treatment.