Across a Lowcountry landscape where few natural inland ponds are found, more than 21,000 acres of man-made ponds now collect rainfall that otherwise would filter into the ground or run off.
More are dug every day.
Nobody fully understands yet how development stormwater ponds hurt or help the overall coastal environment, much less how to manage them. But an effort is underway to find out.
Seven research schools and agencies have agreed to work with the S.C. Sea Grant Consortium, which is seeking funds to bring a "more bang for the buck" approach to various stormwater projects underway.
The idea is to collaborate on the efforts, to find answers for community concerns about the ponds.
The initiative is being launched with $200,000 in combined state and federal grants.
It's long been needed. The ponds have been installed with new buildings for a quarter century. They sequester pollution, such as gasoline, oil, pet waste, fertilizer nutrients, garbage and varnish from lawns and streets, that otherwise would run into the waterways.
But as The Post and Courier reported in July, the build-up of toxic sediment makes the ponds tougher to handle and a high-dollar hazardous substance removal job waiting to happen.
Meanwhile, marine life-killing "algal blooms," a chronic problem in the ponds, have begun to occur in the ocean along the developed Grand Strand beach.
"We don't have a good handle on the characteristics of the ponds and the elements they're bringing in. There's concern out there that people don't know what they have (with the ponds), what the responsibility is and what it means over time," said Rick DeVoe, consortium director.
Ideally, the collaborative effort could lead to more effective ways to design and install new ponds and retrofitting of older ponds that are becoming dysfunctional, DeVoe said.
"I absolutely think (the collaborative initiative) is the right way to go," said algal ecologist Dianne Greenfield, with the Belle Baruch Institute for Marine and Coastal Sciences.
The ponds are complex systems each with different mixes of nutrient loads and hydrodynamics, or flows, she said. Better understanding interactions like that and how the ponds react to the various elements is essential to better management of them.
One example of the ponds' complexity: Algae forms in the water from nutrients the runoff brings, helping to absorb the pollutants to keep them out of the creeks and streams. Except that can lead to algal blooms, aquatic specialists say.
The ponds have become the standard for handling rain runoff at residential and commercial developments.
A recent estimate by Belle Baruch researchers put the number of ponds at more than 14,000 along the South Carolina coast. Charleston officials say there are now more than 800 of the ponds in the city alone.
Along with causing algal blooms, the pollutants leach into the groundwater.
They settle layer upon layer across the bottom until the ponds have to be dredged and the sludge removed at costs that can be hundreds of thousands of dollars - according to a S.C. Department of Health and Environmental Control study 10 years ago.
The research schools are University of South Carolina, College of Charleston, The Citadel, Medical University of South Carolina, Clemson University, Coastal Carolina University, and S.C. Department of Natural Resources.
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