Christine Palm

With cautious optimism, folks working on managing the invasive hydrilla in the Connecticut River are starting to see signs of their efforts. I had the privilege of going out recently with two of them to Chapman Pond in East Haddam, one of the U.S. Army Corps of Engineers (USACE) field research demonstration sites that are part of a coordinated effort to test and treat our waterways. Connected to the Connecticut River by two tidal creeks, Chapman Pond is perfect for such experimentation.

On July 30, the USACE New England District and the Corps’ Aquatic Plant Control Research Program applied a selective EPA-approved aquatic herbicide to Chapman Pond to demonstrate control of hydrilla. You can see in the “before and after” pictures below how dramatically the herbicide appears to be working!

As you can imagine, it’s very important that any herbicide used has little or no long-term effects on important native aquatic plants such as eelgrass (Vallisneria americana) that provides vital underwater habitat for fish and other aquatic fauna. It was thrilling on our visit to see my guides, Dr. Mark Heilman and Shaun Hyde of SePRO (a company supporting USACE on the demonstration project) scoop up handfuls of eelgrass — still as shiny and lush as ever. Meanwhile, the hydrilla — which just weeks earlier had blanketed the pond’s surface with a dense, slimy grey-green mat — was gone! Wild rice (Zizania palustris), an important shoreline plant in the river was also healthy and flowering.

Boaters who zoom across the river may not think too much about its ecology, but they sure do notice when their propellers are clogged up with pervasive hydrilla. Homeowners along the river have seen their formerly pristine views marred. Folks who fish now have a hard time getting their hooks to penetrate the dense mat of slime. And anyone who cares about our delicate web of interconnected waterways is alarmed by hydrilla’s rapid spread to inland lakes and ponds.

PLEASE be part of the solution by ALWAYS cleaning your boat before moving it in or out of the river. Watch this short video by Dr. Heilman explaining the importance of good “boating hygiene.”

DEEP’s “Clean, Drain and Dry” program is vital to help stop the spread of hydrilla. Learn more about it HERE. 

While it’s far too early to claim full success, early research demonstration efforts on the river are encouraging, thanks to the ongoing work of many organizations and people. Efforts to manage and reduce hydrilla are exacting, laborious, time-intensive, and expensive. Everyone involved in this work has my sincerest admiration and gratitude.

The Connecticut River Conservancy is one of those partners. Their ongoing cleanup needs volunteers.

The Lower Connecticut River Valley COG continues to advocate effectively for remediation. 

The US Army Corps of Engineers leads the hydrilla management demonstration program, which has been funded through federal appropriations encouraged by Senator Richard Blumenthal and many other Connecticut and Northeast federal representatives. The demonstration program has the following website with extensive information about the project and its partners.

The Connecticut Agriculture Experiment Station has long been a leader in research. I am proud that a bill I wrote and got passed in 2022 established within CAES the Office of Aquatic Invasive Species. Read more HERE. And if you’re having trouble falling asleep some night, I invite you to read the actual bill HERE.