Below Gills Creek Road in Lancaster County, a stream has stopped flowing. It’s become a pond, stuck behind four metal pipes blocked with branches, garbage, and debris. There's barely any water making its way through to the other side. Cooper McKim speaks with experts on how outdated culverts are impacting both humans and the stream's ecosystem.
Public Works Director, Jeff Catoe, is in charge of managing culverts like this. He says even minor thunderstorms cause these streams to overflow onto the road. Catoe says, "when there's too much water coming, there's also debris coming downstream. They tend to clog those culverts creating a damming effect until the water pushes into the banks. [That] causes damage to the road itself and to the structure." Culverts are intended to allow streams to flow naturally past a road, as a passageway for fish and flowing water.
In 2009, the Fish and Wildlife Service called Catoe and said these road crossings are a hazard to the stream's ecosystem as well. In fact, it's wiping out an endangered mussel species called the Carolina Heelsplitter. A biologist with the Fish and Wildlife Service, Morgan Wolf, says "the Heelsplitter is what's considered critically endangered. We have what's thought to be 154 individuals left on the planet." The majority of the remaining populations are in Lancaster County, stuck in streams like Gills Creek with problematic culverts.
The Carolina Heelsplitter is a small, fresh-water, mussel species native to South Carolina. Wolf says obstructed culverts stop nutrients from making their way downstream. Plus, increased flooding events cause debris to collect in their habitats, or to even wipe out their nests.
Wolf says updating the road crossing structures is one of the first steps to creating a long-term habitable environment for the Heelsplitters. She says, "in the past, they would put in a couple of culverts and then realize that it wasn't passing the water during storm events. So they thought, 'We just need two more.' What they're not realizing is that the stream isn't naturally encompassed within these four structures. Even though they added two more structures, it's not going to accommodate the amount of water flowing through this system."
Wolf says the Heelsplitter is crucial to maintaining a healthy water quality. They're filter feeders use toxins and bacteria for nutrients that would otherwise kill fish. She says, "they can filter at least a gallon of water every hour, that's one mussel, so if you multiply that by a thousand, that's a huge, huge deal for these systems." She adds that Heelsplitters also deserve protecting.
"They can't just pick up, pack up, and move when conditions aren't favorable. We dump all of this just destruction and nasty stuff on top of them, and somehow they just persist. If we don't do something to protect them, it's a large part of our natural history that's going to go by the wayside," Wolf says.
Since the partnership between Lancaster Public Works and the Fish and Wildlife Service (FWS), they've built two new culverts in the County. They're arched structures that let the whole stream pass underneath, uninterrupted. Wolf says they're already working: "There was no flooding on adjacent lands that we were getting before. We got a call from the county a couple of weeks later that said structures look great, they worked perfectly. We were really proud of that. If you could ever have a test for a structure, it would be the 1000 year storm event that we just had." Wolf says, during October's flood, an entire tree trunk passed underneath without getting stuck.
Wolf expects the updated culverts to improve water quality over time, slowly help the Heelsplitter population survive and rebuilt their population. "Fingers crossed, the habitats gonna be there and within the next year we're going to be putting mussels out in this very stream, where once we had written off the heelsplitter," Wolf says.
Links
Information on the Carolina Heelsplitter
Lancaster County Public Works
South Carolina FWS Field Office Info on the Heelsplitter