MIDDLESEX COUNTY — Eighteen legislators are condemning what they say are “false and misleading” social media posts surrounding the safety of using diquat and other herbicides to kill hydrilla in the Connecticut River that “triggered fear” among residents.
Use of the aquatic weed killer is banned in the European Union, United Kingdom and other countries. But Connecticut environmental officials and lawmakers said they support the use of diquat if used appropriately.
Lawmakers, led by state Rep. Renee LaMark Muir, D-Deep River, said in a letter Tuesday the fast-growing invasive species presents a “serious environmental threat” that needs to be addressed.
"Diquat, a non-selective herbicide, when properly applied and in the right amount, is not considered hazardous," the letter reads. "This product has passed comprehensive federal Environmental Protection Agency risk assessments for registration of aquatic use. The state Department of Energy and Environmental Protection permits all aquatic herbicide applications and certifies trained applicators to apply the product."
The controversy stems from an ongoing research and demonstration project being conducted by the U.S. Army Corps of Engineers.
The program now uses three herbicides: diquat dibromide, dipotassium salt of endothall, and florpyrauxifen-benzyl, according to the Army Corps. A proposed modification would add bispyribac-sodium, imazamox, flumioxazin, fluridone, penoxsulam, or combinations of the herbicides.
The agency has identified 12 “potential” sites, including Pameacha Pond and Mattabesset River in Middletown, Chester Creek and Parker’s Point in Chester, Hamburg Cove, Selden Creek and Joshua Creek in Lyme; Portland Boat Works, Post and Pratt coves in Deep River, the Salmon River in East Haddam, and Lake Pocotopaug in East Hampton.
Hydrilla, which can choke waterways, was first identified in the river in 2016 in Glastonbury, according to the Connecticut River Conservancy.
Legislators, including state Reps. Brandon Chafee, D-Middletown, and John-Michael Parker, D-Madison, said in the letter that the rumors allege “federal and state agencies, scientists, and environmental advocates are intentionally harming rather than protecting the river and other waterways.”
Environmental advocates support the program, DEEP said, including The Connecticut Fisheries Advisory Council, which represents a coalition of angling and conservation organizations; and The Connecticut Federation of Lakes.
"Hydrilla is a highly invasive and transmissible plant and its threat to the Connecticut River's natural ecology is very real, including the degradation of river habitat, water quality, native plants, and animals, and the loss of waterway navigability and fishing, lowering of property values, and an increase in flood risk,” the lawmakers wrote.
Inaction, the letter said, could "forever" change Connecticut River ecosystems, which it may "never recover" from.
“If we do nothing, the hydrilla problem will worsen, and other invasives will proliferate," the letter reads. "More chemicals will then have to be used to combat invasive plants.”
Keith Hannon, from the U.S. Army Corps of Engineers New England District, said last week it’s not guaranteed the spraying will occur.
“USACE is navigating permitting and budget constraints, and whether those constraints will continue is mostly unknown at the moment, so there is no commitment by USACE to conduct any herbicide applications anywhere in the CT River basin at this time,” he said.
Meanwhile, DEEP released a statement Tuesday saying "social media posts have claimed that this project has been stopped, paused, or canceled and have raised concerns about the safety of the herbicides."
It then clarified it hadn't been notified the project was paused and it continues to review permit applications for it while the Army Corps is managing the project timeline.
The project is intended to "control its spread and protect the river for future generations,” the agency said.
“While DEEP reviews and issues permits to ensure the work meets environmental and public health standards, the project itself, including the application of federally approved herbicides like diquat, is designed, managed, and carried out by the Army Corps and its certified contractors," the statement reads.
Alternatives to diquat include using mats to cover the plant beds and mechanical removal, but the legislators questioned these methods' efficacy.
"These methods have proven to be ineffective and only worsen the problem," lawmakers said in the letter.
State officials recommend the best way to address hydrilla is to “clean, drain and dry” watercraft and fishing gear after removing them from the water.
“The Connecticut River is our premier natural resource," the letter continued. "As its stewards, we must preserve and protect the river, its ecosystems, waterfowl, and wildlife, and ensure the safety of residents who live along, recreate, or work on the river."
Public comment on the project is accepted until July 13, can be made by emailing [email protected]. To report hydrilla sightings, navigate to portal.ct.gov/deep or ctriver.org.