Carroll County approves $350K plan to eradicate zebra mussels from Hyde's Quarry

Zebra mussels are native to Europe, but have come to North America -- likely in the ballast water from a ship. In 2002, a population was found in the Susquehanna River. They've since spread further in Maryland, including to Hyde's Quarry in Westminster.
Zebra mussels are native to Europe, but have come to North America -- likely in the ballast water from a ship. In 2002, a population was found in the Susquehanna River. They've since spread further in Maryland, including to Hyde's Quarry in Westminster. (Courtesy of Maryland Department of Natural Resources)

The county approved a $349,966 plan to eradicate the zebra mussels that have been dwelling and reproducing in Hyde’s Quarry for at least three years.

Maryland’s Department of Natural Resources confirmed that the mussels — an invasive species that has not been seen on inland Maryland before — were present in the Westminster quarry last May. Since then, the Carroll County Land and Resource Management Department has been seeking a way to remove them before the warm reproductive season, and before they spread to any other water bodies.


“Zebra mussels are a highly invasive species,” Director Tom Devilbiss told Board of Carroll County Commissioners on Thursday. “They had not previously been found in Maryland except within the Chesapeake Bay, the upper parts of the Chesapeake Bay.

“Their occurrence in Hyde’s Quarry was a concern for us as staff, and actually for the state for that matter.”


According to the National Oceanic and Atmospheric Administration’s Minnesota Sea Grant website, the mussel's reproductive cycle is key to its rapid spread and high abundance. Egg production starts when water temperature warms to about 54 degrees, and a fully mature female mussel may produce several hundred thousand eggs per season.

Water supply

The Westminster quarry was originally purchased with the intention of using it as a water source in the future, Devilbiss explained, and zebra mussels are a concern because not only are they highly invasive, they will also interfere with that future use.

“Zebra mussels are very detrimental to the use [of Hyde’s] as a water supply,” he said. “Their prolific nature causes them to choke up and actually render water supply systems, their pipes, almost useless because they clog all those systems up.”

The county gave local dive company Undersea Outfitters until Sunday to move out of Hyde’s Quarry in Westminster after invasive species were found there over a month ago. Maryland’s Department of Natural Resources confirmed the presence of zebra mussels in the lake on May 24.

The almost $350,000 eradication plan will include injecting 400 tons of potash, an alkaline potassium compound, into the quarry to remove the species before they reproduce in the summer.


Devilbiss said the treatment was used in Virginia a decade ago and will not affect any other aquatic species in the quarry — plus the residual effects have kept the mussels from returning in the 10 years since it was applied in the neighboring state and is expected to do the same in Carroll.

He said the county needs to purchase a large quantity of the potash to ensure even distribution at a lethal level.

“You can’t miss these critters,” the director said. “Because they are in all the cracks and crevices; we have to get everywhere so we don't miss anything. We have to get all these critters.”

Commissioner Dennis Frazier, R-District 3, asked if the process would hinder the quarry’s future use as a water source, as residual potash would remain after the treatment.

According to Devilbiss, the quarry would need to have all of its water flushed out and refilled before it could be used as a water source.

“Our goal is to not only eradicate these things, but not let them have the opportunity to come back,” he said.

‘We didn’t put them there’

Commissioner Stephen Wantz, R-District 1, was the only commissioner to vote against awarding the contract to Canada-based ASI Marine Thursday, stating he did not think it should be the county’s responsibility to clear the quarry when it has been used for scuba diving for 18 years.

The mussels are transferred from one body of water to another through contaminated water-related equipment, aquatic plants, fouled boat hulls and other equipment, and in contaminated water, according to NOAA.

“I get it that we’ve got to get rid of them, but we didn’t put them there,” he said. “Wouldn’t there be some responsibility from those we think did?

“This bothers me to the Nth degree,” Wantz continued. “We are going to spend almost a half a million dollars to end something we did not create.”

Devilbiss said unless there is proof, there isn’t anything they can do to hold anyone else responsible.

“It’s a sort of a logical step to how they got in here,” Frazier said. “There aren't too many avenues for zebra mussels to get in here.”

The commissioners asked Devilbiss what would happen if they waited, or decided not to eradicate the mussels.

“Then they continue to reproduce, get a lot worse,”he said. “Another issue: we can’t control access to that quarry 100 percent. Anybody that gets in there could get out, go into another water body with the clothes they have on, and those zebra mussels could be transferred.

“We don't want someone to say they came from Hyde’s Quarry to another water body,” he said. “That’s not what we want to see happen.”

The money

Commissioner Eric Bouchat, R-District 4, agreed with his colleagues that there should be some measure to hold people accountable for bringing the invasive species to the quarry, but said he also understood that the county needs to solve the problem.

“Is there any possibility for grant assistance or anything?” he asked.

Ted Zaleski, director of the Department of Management and Budget, said the money for the project would need to be transferred from three sources: $85,000 from the capital project for environmental compliance, and the remainder from fiscal year 2016 and 2017 pavement management funding that hasn’t yet been allocated.

Only $8,000 in grant funding is available for the project, Devilbiss said, and that is through the Mid-Atlantic Panel on Aquatic Invasive Species.

Wantz was also the only commissioner who voted against making the budget transfers.

“It’s got to be done, but I'm just going to let it go at that,” he said. “We talked about it enough.”

Commissioner Richard Weaver, R-District 2, on the other hand, said he had to vote yes.

“I hate to do this,” said Weaver, “but we have a responsibility for public safety and water quality. We don't have any choice at this point.”

ASI Marine can now begin planning the eradication, which Devilbiss says will be finished before June.