The Bio Survey Group removes protected mussels, making way for work on the Brent Spence Bridge Corridor Project over the Ohio River.
* Divers are relocating mussels from the Ohio River in advance of Brent Spence Bridge construction.
* The relocation is required by law to protect endangered, threatened or potentially threatened species.
* Seven endangered mussel species were found in the construction zone during a 2022 survey.
Chase Mowry steps out of a 25-foot flat bottom boat on the Kentucky side of the Ohio River, the Brent Spence Bridge above providing limited shade on a 90-degree afternoon.
He dons a helmet, attaches an oxygen line and ventures about 20 feet off shore and 20 feet under water.
He's on the hunt for mussels.
A half hour later, he emerges with his catch: a single threehorn wartyback mussel, its closed shell measuring no more than an inch.
By day's end, the wartyback will have a new home, just upstream, relocated as part of the Brent Spence Bridge Corridor Project.
And the $3.6 billion bridge project will hit a new milestone. Actual construction must be underway by this time next year - or the hunt for mussels will have to be repeated.
7 mussel species found in 2022
Under law, transportation officials must determine the environmental impact of infrastructure projects on species that are endangered, threatened or potentially threatened. That's required whether a location for work actually hosts the listed species or is just suitable for them.
In a 2022 survey of Brent Spence construction locations in Ohio, officials determined one herb, four bats and two fish species would be impacted or potentially impacted.
They also identified seven kinds of endangered mussels as vulnerable, finding 216 of them in bridge construction areas. The list included 108 wartybacks, 101 washboards, two ebonyshells, two Ohio pigtoes and a single sample each of elephantear, monkeyface and butterfly mussels.
The Ohio Department of Natural Resources requires that the endangered mussels - and, indeed, all mussels - be moved out of harm's way.
Over the last two weeks, that work fell to BioSurvey Group, a biological consulting firm from Liberty, Indiana, that's handled mussel relocations in more than 15 states.
Finding mussels 'all by touch'
Two crews from BioSurvey worked the Kentucky side of the river, directly under the Brent Spence, on the afternoon of Aug. 15.
As Mowry entered the water, four other members of his crew steered their boat away from shore and monitored his progress. He combed the river's bottom one meter at a time, focused on the area on the western edge of the Brent Spence where a brand new double-decker bridge will be built.
Divers develop expertise in finding mussels in the murky Ohio, said Matt Gilkey, aquatic biologist with BioSurvey. "It's all by hand. It's all by touch," Gilkey said.
They come to BioSurvey with diving know-how, added Ryan Schwegman, the firm's chief operations officer. "We teach them how to find mussels," Schwegman said in an interview with the Ohio Department of Transportation.
Mussels need salvaging not just because the state requires it, Schwegman explained. They are also worth saving, he said, because they protect the river's ecosystem by filtering impurities like algae and bacteria and serving as food for other aquatic life.
"We're doing our part to protect the resource and keep it for future generations," he said.
Sometimes, divers find thousands of mussels. Sometimes, they don't
Sometimes, BioSurvey divers find and relocate thousands of mussels during a job. Just last year, its website reported:
* They worked with four other firms to move more than 9,000 in downtown Grand Rapids, Michigan, for a dam removal project in the Grand River.
* They collected more than 1,600 at the now-closed William H. Zimmer Power Station near Moscow, Ohio, for a dredging project in the Ohio River.
* They collected more than 1,000 from the Great Miami River near Troy, Ohio, for a proposed dam removal project.
In Cincinnati, divers harvested just 57 mussels under the Brent Spence over two weeks. With a contract worth $200,000, that comes to about $3,500 per mussel.
Each day, divers deposited the mussels they found in mesh bags that remained submerged in the river. Each afternoon, the crew dumped the day's take about a half mile upstream, near the John A. Roebling Suspension Bridge.
"We just drop them from the boat and let them burrow," Gilkey said.
That included the threehorn wartyback that Mowry pulled up, which is not among the endangered Ohio wartybacks. If it was endangered, Gilkey and his colleagues would have had to place and catalog it individually in a new spot.
Even zebra mussels get a new home
Cincinnati restaurants that serve mussels - mostly in dishes with wine or red sauce - likely buy saltwater varieties from seafood farms or commercial ocean fisheries.
The Ohio River and other inland waterways are home to freshwater mussels.
Pesky zebra mussels are among the most plentiful in the Ohio, with broken shells among the twigs, trash and other debris where the BioSurvey boats worked under the Brent Spence.
Zebras are considered invasive, attaching themselves to boats, rocks, piers and each other, crowding out other native species.
But even those have to be relocated.
"Every single mussel is considered protected," Gilkey said. "We're moving everything we find."