A proposed indoor salmon farm on Maryland’s Eastern Shore is poised to clear a key regulatory hurdle over critics’ fear that its discharges will threaten the state’s only Atlantic sturgeon spawning grounds.
The Maryland Department of the Environment has issued a tentative permit that would allow the salmon-rearing facility to discharge up to 2.3 million gallons a day of treated “purge” water into Marshyhope Creek, a tributary of the Nanticoke River.
The Marshyhope is the only waterway in Maryland known to harbor spawning sturgeon. The long, bony-looking fish are federally classified as endangered along most of the East Coast, including the Chesapeake Bay region.
It’s the first of several permits that AquaCon, the Norwegian aquaculture company proposing the salmon farm, needs to begin construction. Others include water appropriation, stormwater, wetlands, and waterways, as well as an aquaculture permit from the state Department of Natural Resources.
An AquaCon official said the company has gone to great lengths to ensure that the wastewater discharges don’t upend Marshyhope’s ecosystem.
“We have spent more than one year with MDE on the permit terms,” said Henrik Tangen, executive chairman and president of AquaCon. The state’s discharge conditions, he said in an email, “are significantly more stringent than comparable terms for other similar facilities [worldwide], the U.S. included, taking all local environmental issues into consideration.”
The company, which went public with its plans in 2020, aims to raise fish inside a $300 million, 25-acre building in an industrial park on the outskirts of Federalsburg, a small town in rural Caroline County. According to AquaCon’s website, it’s one of four such facilities that the company hopes to build in Maryland to supply the Mid-Atlantic region with the popular fish.
Concerns for sturgeon
By AquaCon’s own calculations, discharges from the Federalsburg facility would compose up to 15% of the Marshyhope’s water flow. Several environmentalists say the creek is too small to absorb that much wastewater.
“We’re really strongly opposed to this,” said Judith Stribling, a retired Salisbury University biology professor and former president of the Friends of the Nanticoke River. “The notion of salmon aquaculture is admirable, and the objective of producing good, quality food that would in most places not have a serious impact on the environment seems like a good one. But this location could not be worse.”
Environmentalists point to several issues with the wastewater. Among them: It will be colder than the water in the surrounding river during the summer, potentially upsetting the spawning season; the purged water could contain diseases and chemicals harmful to aquatic life, and any change in the stream’s salinity or other water chemistry could affect sturgeon spawning.
The wastewater would enter the creek just upstream of the MD Route 313/318 bridge. That would put the discharge just outside the portion of the Marshyhope designated by the National Oceanic and Atmospheric Administration’s fisheries unit as critical habitat for sturgeon. The bridge marks the classification’s upstream boundary.
Still, sturgeon have been documented swimming in the creek above the bridge, according to state surveys.
Although the Endangered Species Act protects sturgeon and their critical habitats, federal agencies have taken no direct role in reviewing the potential impact of the AquaCon project. That responsibility is delegated to the state in this case, according to Sean Corson, Bay office director for the National Oceanic and Atmospheric Administration.
Lee Currey, director of MDE’s water and science administration, said his agency’s staff believes the permit limits and requirements they have proposed should safeguard Atlantic sturgeon.
Even so, he added, “The applicant will need to be able to demonstrate to us that their design is going to be able to achieve these.”
Wastewater management plans
If built, the Federalsburg facility would produce up to 16,000 metric tons of salmon a year, company officials say.
The company plans to use a “recirculating aquaculture system,” in which the fish will be raised in a series of large indoor tanks filled with water from wells. That water will be almost completely recycled, with fish waste filtered out and converted to methane to supply energy for the operation.
Up to 60,000 gallons of wastewater from processing the fish for the market will be piped daily to the town of Federalsburg’s sewage treatment plant, which also discharges to Marshyhope Creek. Naomi Howell, MDE’s chief of industrial wastewater permitting, said that plant’s discharge permit is up for renewal, and the agency plans to impose new requirements related to the plant’s handling of the aquaculture facility’s waste.
The town’s wastewater plant will be able to handle what’s piped over from the factory with 300,000 gallons of capacity to spare, said Lawrence DiRe, Federalsburg’s town manager.
The aquaculture facility’s only direct discharge to Marshyhope Creek will be from tanks used to “polish” the salmon before harvest, by purging them of bacteria that can affect their flavor. The bacteria that cause that muddy flavor in fish, known as geosmin, are naturally occurring, the company says, adding that it plans to disinfect the water before discharging it.
Because some area residents eat fish caught in the creek, MDE says it will require AquaCon to submit a study to show that its discharge won’t give those fish that unfavorable flavor.
The salmon will be cut off from food for several days prior to and during purging, so it’s expected the discharge will contain relatively little fish waste. But with the creek already impaired by some pollutants, MDE will require AquaCon to offset the phosphorus and nitrogen it’s projected to discharge to the creek.
One of the biggest concerns about the discharge is its temperature, which some fear could harm spawning sturgeon. The endangered fish tend to spawn from spring through summer when water temperatures warm up.
An MDE fact sheet lists the facility’s discharge temperature as 56 degrees, based on the company’s plans to draw its purge water from wells. But a 2021 study by fisheries ecologist Dave Secor and colleagues at the University of Maryland Center for Environmental Science reported sturgeon spawning activity in the creek in September when water temperatures ranged from 68 to nearly 81 degrees.
In a letter earlier this year to MDE, a Department of Natural Resources official said state biologists worried that such coldwater discharges could create a “thermal barrier” in the creek that would restrict fish movement. While most of the sturgeon spawning observed in the creek has been well downstream, the fish have been tracked all the way up the creek past the proposed plant’s outfall.
MDE plans to limit the thermal impact of the facility’s discharge by dictating that the creek water temperature within 120 feet of the outfall cannot vary over a 24-hour period by more than about 3.5 degrees from elsewhere in the creek.
If that is not possible, the agency says the company would be required to take steps to reduce the temperature alteration.
AquaCon chairman Tangen said meeting that would be “no issue,” even though it would be an added operating cost. He said that the company’s executives and advisers have “long experience” in safeguarding wild fish spawning based on their work designing and operating other operations like this one.
“With the terms set for the permit we are most comfortable on this particular issue,” Tangen said.
Success in other locations
In drafting the permit, MDE reviewed discharge requirements imposed by Maine regulators on two similar land-based salmon farms proposed near the Atlantic coast there. MDE also consulted with aquaculture and sturgeon experts in and out of government.
Ian Bricknell, professor of aquaculture biology at the University of Maine, said he reviewed AquaCon’s project and saw nothing of concern. Indoor aquaculture systems like this have been more successful at keeping out diseases and parasites than operations overseas that raise salmon in open water pens, he said, so they have less need of treating the fish with antibiotics or chemicals.
“When I spoke to them, they had a good plan,” he said. “It was a very sound design and should work well.”
Secor, the UMCES researcher, said the Maine salmon facilities differ from the proposed Maryland operation in one critical way: the size of the waters receiving a discharge. The Maine facilities would drain into vast coastal waters, while the Federalsburg project would release wastewater into the upper reaches of a creek, dozens of miles from open water.
“The only similar factories occur on much larger coastal bodies (e.g., the Penobscot Bay) where the failsafe of dilution of released sewage and biocides makes sense,” Secor said in an email.
Maryland’s state biologists raised several concerns. In his May letter, Tony Redman, the DNR’s environmental review director, said the permit terms MDE had drafted addressed some of his department’s concerns. But he called for frequent or even continuous monitoring of the plant’s discharge, warning that even a one-day deviation in acidity or dissolved oxygen levels from the wastewater could cause a fish kill.
He also noted that salinity in the water influences spawning among fish like sturgeon that migrate upstream from the Bay to reproduce, and he urged close monitoring for changes in salinity and conductivity, a more sensitive general indicator of water quality.
“We’ve tried to address all the concerns that we’ve heard,” MDE’s Currey said. But regulators want more information before making a final determination to issue a discharge permit. Toward that end, MDE has scheduled a public hearing at 5 p.m. on Aug. 10 at the Federalsburg Town Hall, 118 North Main St. Comments received by Aug. 17 also will be considered.
“There still needs to be a demonstration to us that the technology being used meets the requirements necessary to protect the aquatic community,” Currey said. “There’s still a ways to go.”