On a clear, cool winter day, 20 seniors and two teachers from the Charleston Charter School for Math and Science (CCSMS) got a chance to spend a few hours visiting Polk Swamp near the Town of St. George in upper Dorchester County with several U.S. Army Corps of Engineers, Charleston District engineers and scientists. CCSMS’ mission is to educate students for success in college and careers by providing an “innovative learning environment.” That “innovative learning environment” became, for a few hours and for those 20 seniors, Polk Swamp.
Polk Swamp is part of the Edisto River watershed, which is the longest undammed blackwater river in the U.S. It also contains a large stand of bottomland hardwood trees, which are disappearing at a rapid rate in the swamps and wetlands of the southeastern U.S. These trees, with their unique knee-like roots that grow toward the sky, have been damaged and destroyed from decades of ice and wind storms, tree falls, poor logging practices, and beaver infestations, which have also caused flooding from numerous obstructions to the natural flow of the swamp.
The students were invited to visit the swamp so they could learn how members of the Polk Swamp project delivery team were solving the problems at the swamp. Upon arriving at the site, they received an overview of the District’s missions and Polk Swamp and the history of the project. The class broke out into two groups; one went to learn about the ecosystem and one went to learn about hydraulic engineering and after 45 minutes, the groups switched.
Jesse Helton and Mark Messersmith, biologists, presented the ecosystem session. Helton and Messersmith discussed the importance of wetlands and how to identify them. Students were given the opportunity to take soil samples using an auger to compare upland and wetland soils. They were also asked to compare adaptations of plant species found in uplands to those found in wetlands. Students were very eager and asked about the District’s ongoing study in Polk Swamp and what kinds of career opportunities are available in the Corps. Helton and Messersmith also recalled to the students a recent day in the field where they traversed 11 miles of swamp choked with weeds, cattails, beaver dams and fallen trees with representatives from Dorchester County. The team donned hip waders and used canoes to move through the swamp, locating, documenting, and photographing major blockages to model the conditions of the swamp in order to develop alternatives to restore the stream channel and hardwood forest habitiat.
“I really enjoyed going down to the swamp and learning how beaver’s dams can cause a lot of damage to the ecosystem and how the dam can block off the water that the swamp needs,” said Antavius Farr-Heyward, a student at CCSMS.
The hydraulic overview was presented by Sara Brown, hydraulic engineer, and assisted by Anne McCartney, civil engineer. Brown explained that the role of a hydraulic engineer is to predict flows from a watershed, compute water levels, consider the impacts to the floodplain, assess how to improve water levels, and consider how to implement or construct a project that will improve the overall hydraulic, and in this case, environmental conditions in the watershed. Students were shown how District engineers prepare for field visits to Polk Swamp by gathering information such as maps, aerial photographs, land use and topographic data, past studies, rainfall data, etc. Brown explained how all this data plus information gathered during the fieldwork would be used to develop a model of the hydraulic conditions in the swamp. Students were asked to consider what other types of information would be needed before alternatives could be developed to implement and construct a project that would restore the hydraulic conditions to a more natural state.
Before departing, several students walked to the edge of the swamp, broke off cattails, and proceeded to “cover” the area with clouds of fluffy white cattail seeds, concluding their day in an “innovative learning environment.”