In their efforts to combat the spread of a highly-invasive weed along the Connecticut River, scientists, conservation groups and public officials say they’ve had to confront a new problem that grows with even more alarming speed: online misinformation.

Their concern stems from a viral campaign that sprang up this week in opposition to an ongoing project by the Army Corps of Engineers to use chemical herbicides to halt the spread of hydrilla, an invasive plant that has taken over wide swaths of the river since it was first identified in the state in 2016.

In posts on social media and opinion pieces, critics have accused government officials of planning to “poison” rivers in Connecticut with the chemical diquat dibromide. Others have raised suspicions about the timing of project itself, which is scheduled to begin again after the July 4 holiday.

While officials acknowledge the use of diquat, they say it is being done in compliance with state and federal regulations following lengthy studies along the Connecticut River itself.

“We appreciate the strong interest in the U.S. Army Corps of Engineers’ efforts to combat the spread of this invasive and highly transmissible strain of Hydrilla,” Keith Hannon, the project manager for the Army Corps’ New England District, said in a statement Thursday.

“The threat of this strain to the Connecticut River’s natural ecology are real, and include degradation of river habitat and water quality, and harm to native plants and animals,” he added. “Additionally, the strain could affect the local economy through the loss of waterway navigability and fishing, lowering of property values, and increase in flood risk.”

Much of the attention to the project in recent days appears to have come from a series of social media posts made by Chris Webby, a Connecticut-based rapper who boasts more than 128,000 followers on X. In one video posted last weekend, Webby referred to the officials behind the project as “scumbags” and “filthy crooks.” The video was later shared by another account with more than 1 million followers.

An online petition circulated later by Webby has gathered 14,868 signatures as of Thursday.

When contacted Thursday about his posts, Webby said that he was “not an expert” on hydrilla or herbicides, and that he had done much of his research using ChatGPT after coming across social media posts by a man claiming to show the effects of diquat spraying on a lake in Texas.

That research led Webby to discover that diquat is banned in the European Union, and that it can have toxic effects on other aquatic plants and wildlife besides hydrilla.

“My question is, ‘Why diquat? Why the hold up after the fourth [of July]?'” Webby said in an interview Thursday. “Why now? Why all these places? We have questions. I’m not the only one.”

But public officials and local advocates who have worked for years with the Army Corps to combat the spread of hydrilla say that answers to each of those questions, and others, are available to anyone who has taken the time to ask them.

“It’s unfortunate that this really serious problem had to come to light through misinformation and conspiracy theories,” said Alicea Charamut, the executive director of the Rivers Alliance of Connecticut, a nonprofit conservation group.

Responding to Webby’s questions about why officials don’t look at using other, mechanical means to combat hydrilla, Charamut said they did consider using a device known as a “benthic mat” that prevents the plant from growing up from the river bottom. That proved impractical, she said, because of the speed at which hydrilla grows and the fact that the mats would also smother other, native plants.

“You’d have to cover the entire river in mats. It just doesn’t work,” she said.

Jeremiah Foley, a research scientist at the Connecticut Agricultural Experiment Station’s (CAES) Department of Environmental Science and Forestry, said the timing of the project is dictated by the life cycle of hydrilla. Infestations of the plant typically reach their peak in late summer, when they create dense mats that can crowd out native species, clog boat propellers and even block access to parts of the river.

The purpose of the project, he said, is to disrupt the plants before they reach their peak and begin spreading small sprouts, known as turions, that form into new plants the following year.

Allies of the project also bristled at Webby’s assertions that the use of diquat is being carried out in “secret” without public input. The reality, they say, is the Army Corps spent years studying the use of herbicides and holding public meetings to devise the best methods of fighting hydrilla without harming the broader ecosystem.

“Some of the stuff I read was that it was quietly passed, nobody knew, or they’re trying to get money for their programs … I mean, that’s really not based in reality,” said Bill Lucey, the Long Island Soundkeeper at the environmental nonprofit Save the Sound.

In 2023, Foley began working with the Army Corps to conduct experiments using dyes to study the flow of water in areas where they planned to use herbicides. By watching where the dyes went, he said, researchers gained a better understanding of where to apply the smallest amounts of herbicides necessary to attack the hydrilla.

“A lot of people have the misconception, when you put a chemical in the water, it is just flowing out of the system everywhere, and that is absolutely not the case,” Foley said.

Based on the results of those studies, the Corps decided last year to move forward with a plan to begin applying herbicides, including diquat, in five areas along the river. Before doing so, officials held three public meetings in towns along the river to present the plans, and Foley said he and other researchers conducted a inventory of all the aquatic vegetation within the selected sites so they would be able to go back later and see what was left.

“What we find is that many of those native plants that we recorded not only were still there, but [were] increasing in abundance,” Foley said. “At the same time, those invasives that we were targeting, principally hydrilla, are knocked out of the system.”

Foley’s experiments using dyes drew notice from national outlets such as the New York Times, which published an article on those efforts nearly two years ago. The actual treatments using herbicides were carried out in a series of demonstrations last summer that were open to the public, according to notices published last year by the Army Corps.

Last month, the Army Corps published another notice of its plans to expand the project to a dozen additional sites this summer along the Connecticut River, its tributaries, and one lake and a pond. The Corps also opened a public comment period on its plans, which remains open through July 13.

Foley said much of the work this summer at the new sites will likely be limited to conducting dye tracing experiments before crews can even attempt to apply herbicides.

Hannon, in an email Thursday, said the Army Corps does not yet have the state permits necessary to conduct its proposed herbicide applications this summer, and will publish an updated schedule of its plans once those applications are in place. An official with the state Department of Energy and Environmental Protection said in a statement that the agency has been “in touch” with the Army Corps regarding their plans to ensure that officials comply with all applicable state laws and regulations.

Christine Palm, a former state lawmaker from Chester who championed many environmental causes — including the establishment of CAES’ aquatic invasive species program — was among those who spoke out against Webby’s viral claims this week.

“He does not have credibility in the scientific world or in the environmental advocacy world,” Palm said. “He has wreaked havoc on years of thoughtful, careful, expert work.”

In response to those criticisms, Webby said he had reached out to officials at the Army Corps and DEEP and never heard back. He added that suspicions about the project have been validated by the feedback he’s received from others online.

“I’m not saying this is not being done for a reason. I’m saying I don’t like the sound of it,” Webby said. “It sounds like a lot of other people don’t like the sound of it.”

Charamut, with the Rivers Alliance, said she understands the public’s fear over the use of herbicides, which her group has fought to limit in the past. But the aggressive nature of hydrilla — which has spread as far north as Massachussetts — has left officials with no other viable alternatives, she said.

One positive result of the sudden attention to the project, she said, is an increase in calls to the Rivers Alliance from people asking about hydrilla and methods to combat it.

“People should be asking questions. This process was set up to give people that opportunity,” Charamut said. “But get your answers from trusted sources… not a rapper on the internet.”

Mark Pazniokas contributed to this article.