By MARY SELL, ALABAMA DAILY NEWS
The elephant-ear mussels in the Cahaba River are getting old.
The large mollusks serve as filters for the river and a food source for other animals that call the river home, including otters and turtles. They can live to be about 80, researchers say. But a few decades ago, they noticed a lack of young mussels in the river.
“This mussel is still living in the Cahaba River and it has not reproduced because it’s cut off from its host fish,” said Paul Johnson, program supervisor at the Alabama Aquatic Biodiversity Center within the Alabama Department of Conservation and Natural Resources.
That host fish is the Alabama shad, which should play a critical role in the reproduction cycle of the elephant-ears, carrying their larva up river. The shad and elephant-ear mussels are some of the many species impacted by the construction of dams on the Alabama River more than 40 years ago, Johnson said. Decades ago, many large fish from the gulf would swim all the way to the Cahaba.
“They used to have mullet runs in the Cahaba,” Johnson said. “And used to be able to catch 300-pound gulf sturgeon up there too.”
Now, the Army Corps of Engineers is in year one of a three-year study of possible ways to get fish around two dams on the Alabama river – the Millers Ferry Lock and Dam, completed in 1974 and located southwest of Selma, and the Claiborne Lock and Dam, completed in 1970 northwest of Monroeville.
“The basic idea is to restore a fish passage to the lower Alabama River and to connect the Cahaba River to allow the passage of fish naturally up the Alabama River into the Cahaba River, as was historically the case,” said Johnson, who is also a former director of the Tennessee Aquarium Research Institute.
The Nature Conservancy is putting up about $1.5 million in money and in-kind work as the required private partner on the study.
“Without human modifications, the Cahaba River, and really all of the rivers in Alabama, were directly and intimately connected to the Gulf of Mexico,” said Mitch Reid, executive director of The Nature Conservancy in Alabama. He called the effort to restore the rivers “the most significant ecological restoration project in the history of North America.”
Other impacted fish include the paddlefish and large striped bass.
Removal of the dams, around which local tourism and industry has been built, isn’t the end game, Reid said. He said canals that mimic natural rivers with flowing water could be an option.
“We have to move these fish,” Reid said.
He said it would be a “massive” project, but an economic opportunity for the Black Belt, as would more and bigger fish.
Blake Hale Hardwich, executive director of the Coosa-Alabama River Improvement Association, said she’s been in on some of the study conversations.
For Hardwich, who said she supports the recreational use and commercial navigation on the river, the worst-case scenario would be removal of the dams that also provide flood control.
The Army Corps owns and operates both locks. They do allow for boat traffic, but must be scheduled in advance with the Corps. According to the Corps, it receives around $1 million annually for the operation and maintenance of the two dams. It received just over $1 million in fiscal 2022 and should get about $1.3 million in 2023.
The Corps did not answer questions about the ongoing study.
Hardwich would like to see more commercial navigation restored on the Alabama River and hopes some ongoing dredging projects will help that.
“We’re trying to get business back on the river,” Hardwich said. “… My argument is to bring back commercial navigation and you’re not going to have an issue because you’re going to have the locks and dams in use.”
The corps told Alabama Daily News dredging along the Alabama River will begin near river mile 17 and continue north toward Claiborne Lock.
“This stretch of river is where most of the shoaling occurs,” the corps said in a written statement. “The dredge will mobilize to the project site in a few weeks and operations are expected to last approximately four to five months.”
The Alabama River predominantly has recreational vessels, however dredging of the channel could allow for commercial vessels to navigate the river system.
“There is interest from commercial barging companies that carry materials such as crushed stone, sand and gravel,” the Corps said.
Reid said the Corps tried in the mid-2000s keeping the locks open more frequently to allow fish to travel up river. It didn’t work, he said.
“They key in on flowing water, its velocity and how it tumbles over rocks,” he said.
Rep. Kelvin Lawrence, D-Hayneville, whose district includes Wilcox County where the Millers Ferry Dam is, said people he’s heard from are generally positive about the study.
“When you try to alter things that have been a certain way for a long time, there are some concerns, but I think, for the most part, the community is receptive (to the study,)” Lawrence said.
He said the river and dam are a tourist destination for the area.
“I think providing more fish, that would be a great thing and very well received by the community,” Lawrence said.
Reid is confident the study will lead to changes. If it doesn’t, other changes could be forced. If those elephant ear mussels in the Cahaba collapse, other species will be endangered.
“Then you can’t do anything with the river, because of the Endangered Species Act,” Reid said.
“… We’re trying to get ahead of that, but we know we’re running out of time.”