Select Page

2014-2016 Research Projects: Sustainable Coastal Development and Economy

Project: Evaluating the cause and effect after twenty years of assessing the impacts of coastal development on tidal creek headwaters

Principal Investigator

Denise Sanger, South Carolina Department of Natural Resources

Project Number

R/ER-41

Research Description

Relationships have been developed between coastal development and tidal creek environmental quality; however, further study is needed to determine whether the relationships observed are causal. Using data collected starting in 1994, the research team will revisit a number of systems that have undergone further development to determine if coastal growth has caused the ecosystem-level changes that have been observed. A number of the systems studied have since “jumped” land-use categories, and many of the natural watersheds previously studied have now been developed using Best Management Practices (BMPs), including stormwater ponds, to control runoff.

This study will provide new ecosystem-scale information to determine if the use of stormwater ponds has resulted in documentable reductions in pollutants or improvements in water quality. The overall goal of the project is to assess and refine the existing models relating the environmental quality in tidal creeks to their surrounding land use over a 20-year period.

The research team plans to (1) evaluate land cover, demographic, and modeled stormwater runoff changes in 48 tidal creeks over a 20-year period, (2) sample 18 tidal creek systems to determine if there are cause-and-effect relationships between coastal development and tidal creek environmental quality, (3) validate the relationships previously identified and assess the influence of BMPs, (4) develop predictive relationships to understand the impacts of continued development on the coast of South Carolina, and (5) develop outreach materials for target audiences in coastal South Carolina.

Research Results

McHouell, Brian. Master’s thesis, “Evaluating the Impacts of Coastal Development on the Sinuosity and Water Quality of Tidal Creek Headwaters in the Southeast .”  2016, College of Charleston.

Contact for Questions

Denise Sanger (sangerd@dnr.sc.gov)

Project: Hydrology and pollutant removal in detention ponds typical of the lower coastal plain of South Carolina

Principal Investigator

Erik Smith, University of South Carolina

Project Number

R/ER-42

Research Description

South Carolina resource managers and stormwater engineers require locally relevant quantitative information on the residential stormwater ponds typical of the coastal plain. Stormwater ponds, especially detention ponds, are the most common best management practice (BMP) for controlling runoff in coastal South Carolina. No studies published for coastal South Carolina have successfully constrained the relative roles of surface versus groundwater inputs, though groundwater is a significant component of watershed hydrologic budgets due to the region’s low gradient topography and shallow water table conditions. Researchers will determine the performance of ponds typical to coastal South Carolina with respect to hydrology and their ability to remove or retain nitrogen, phosphorus, sediments, and bacterial pathogens. Research will directly account for the relative roles of both surface water and groundwater flowpaths as sources of material delivery to ponds. The study will be conducted in ponds that vary in the degree of impervious surfaces within their catchment area and in the means by which runoff is routed to the ponds.

Over the course of this study, research will (1) quantify the complete water budget for selected stormwater ponds over the course of a year to understand temporal variability associated with rainfall and water table conditions; (2) quantify concentrations of pollutants in pond outfall and input waters to determine detention pond effectiveness; (3) quantify and compare water budgets and pollutant removal in a pair of ponds that vary in residential development density and a pair of ponds that vary in density of connected impervious surfaces; and (4) incorporate research findings into technical recommendations for regulatory agencies, local stormwater managers, pond management professionals, homeowner associations, and the broader scientific community.

Research Results

Corley, Samantha. Master’s thesis, “Quantifying Water Budgets to Evaluate the Hydrologic Performance of Two Stormwater Detention Ponds in Coastal South Carolina ,” 2015, Coastal Carolina University.

Contact for Questions

Erik Smith (erik@belle.baruch.sc.edu)

Project: Evaluating wetland function in coastal South Carolina to support low impact development (LID) decision-making

Principal Investigator

Daniel Hitchcock, Clemson University

Project Number

R/ER-43

Research Description

Coastal development increasingly combines low impact development (LID) practices, such as vegetation-based stormwater control, with traditional Best Management Practices (BMPs) like storm water detention ponds. Properly designed stormwater control measures (SCMs), such as incorporating vegetation for water quality improvement, may be a viable complement to or alternative for stormwater detention ponds. In coastal areas with shallow water tables and low gradient topography, surface and groundwater coupling complicates decision-making with respect to LID and stormwater management. The researchers will investigate the ecohydrological functions, including groundwater-surface water interactions, of natural and engineered wetland systems in the South Carolina coastal plain for stormwater quantity and quality management. They will also determine water table elevations and ranges for soil types typical in the region in order to determine suitability of infiltration and retention practices. The information collected will be publicly available through the Community Resource Inventory (CRI) and aid the development of an LID suitability index.

The researchers plan to (1) determine water budgets, nutrient and bacteria loading, and performance of natural and designed wetland systems; (2) develop siting requirements, design criteria, and specifications for wetland systems based on Objective (1); (3) define shallow water table ranges and variability for soils found in coastal South Carolina; (4) mine existing data and develop metrics and LID suitability indices to populate the online CRI and increase its utility for LID decision-making; and (5) convey these results to practitioners and decision-makers via the online CRI, various extension materials and programs, and by supporting the LID guidance manual.

Research Results

Hitchcock, D. R., A. D. Jayakaran, and D. L. White. “Green Infrastructure in Coastal Landscapes: Ecological Design, Hydrological Function, and Sustainable Land Use Goals ,” Journal of South Carolina Water Resources, 2014.

Jayakaran, A.D., T.M. Williams, W.H. Conner, D.R. Hitchcock, B. Song, A.T. Chow, and E.M. Smith. “Monitoring Water Quality Changes in a Forested Freshwater Wetland Threatened By Salinity ,” Proceedings of the 2014 South Carolina Water Resources Conference.

Contact for Questions

Dan Hitchcock (dhitchc@clemson.edu)

Project: Development and validation of a novel molecular tool to rapidly detect and quantify harmful algal bloom (HAB) species linked with fish kills and public health concerns

Principal Investigator

Dianne Greenfield, University of South Carolina

Project Number

R/ER-44

Research Description

In coastal South Carolina, harmful algal blooms (HABs) are associated with one out of every four fish kills, and phycotoxins are routinely detected, making HABs an environmental and public health threat. Traditional methods for identifying and quantifying HABs use time-consuming microscopy, and many species are morphologically similar, which is problematic for both developing early warning systems and informing management decisions. Researchers propose to develop and apply a novel, cost and time-efficient genetic tool, Sandwich Hybridization Assay (SHA), which will enable water quality managers to rapidly detect and quantify harmful algal bloom (HAB) species associated with coastal fish kills and toxin production. SHA detects large subunit rRNA sequences using 2 oligonucleotides (signal and capture), with results reported as optical densities. Research will focus on the ichthyotoxic raphidophytes Fibrocapsa japonica and Chattonella subsalsa, as well as the domoic-acid producing diatom Pseudo-nitzschia pseudodelicatissima, since they pose serious regional environmental and public health threats.

Over the course of this project, researchers will (1) develop species-specific rRNA-targeted oligonucleotides for F. japonica, C. subsalsa, and P. pseudodelicatissima for regional populations,  (2) validate probe specificity using a variety of phytoplankton species, (3) evaluate assay ranges, limits of detection, and quantification by generating standard curves against known concentrations of cultured isolates, (4) validate laboratory-based quantification against environmental samples containing natural phytoplankton assemblages, and (5) transfer technology through workshops and peer-reviewed literature for enhancing end-user monitoring.

Contact for Questions

Diane Greenfield (dgreenfield@belle.baruch.sc.edu)

Project: Particle contamination: Direct effects on salt marsh-tidal creek organisms and indirect effects on the bioavailability and toxicity of polynuclear aromatic hydrocarbons (PAHs)

Principal Investigator

Stephen Klaine, Clemson University

Project Number

R/ER-45

Research Description

An emerging concern among environmental toxicologists and natural resource managers is the risks that manmade particles, such as nanomaterials, microplastics, and titanium dioxide, pose to marine ecosystems. It is still largely unknown how these particles will behave relative to that of naturally-occurring particles. Particle pollution may have direct adverse effects on organisms and indirect effects through delivery of adsorbed contaminates. In the water, particles can adsorb and change the behavior of organic contaminants such as polynuclear aromatic hydrocarbons (PAHs). While some collection and characterization of plastic debris has occurred throughout the world, no study has been reported for estuaries. Further, little work has been performed characterizing the direct and indirect adverse effects of particles on estuarine organisms. The researchers will quantify the direct effects of anthropogenic particulate contaminants on aquatic invertebrates and characterize the influence of these particles on the bioavailability and toxicity of a model organic contaminant, fluoranthene.

The researchers plan to (1) collect and characterize microplastics in South Carolina estuaries, (2) characterize the adsorption of a model PAH, fluoranthene, to microplastic debris and to two nanoparticles, multiwalled carbon nanotubes, and titanium dioxide in the presence of dissolved organic carbon, (3) quantify the innate toxicity of microplastics and nanoparticles on grass shrimp and copepods, and (4) quantify the bioavailability of adsorbed fluoranthene to shrimp and copepods.

Research Results

Au SY, Bruce TF, Bridges WC, and Klaine SJ. 2015.  “Responses of Hyalella azteca to acute and chronic microplastic exposures .” November 2015. Environmental Toxicology and Chemistry.

Weinstein JE, Crocker BK, Gray AD.  “From plastic to microplastic: degradation of high density polyethylene, polypropylene, and polystyrene in a salt marsh habitat .” Environmental Toxicology and Chemistry. July 2016.

Gray, AD, Weinstein JE. “Size- and shape-dependent effects of microplastic particles on adult daggerblade grass shrimp (Palaemonetes pugio) ,” Environmental Toxicology and Chemistry. November 2017.

Gray, AD, Wertz H, Weinstein JE. “Microplastic in two South Carolina Estuaries: Occurrence, distribution, and composition ,” Marine Pollution Bulletin, February 2018.

Au, Sarah. Doctoral dissertation, “Influence of Microplastics on Aquatic Organisms ,” May 2015, Clemson University.

Wertz, Hope. Master’s thesis, “Marine debris in Charleston Harbor: characterizing plastic particles in the field and assessing their effects on juvenile clams (Mercenaria mercenaria) ,” August 2015, College of Charleston.

Contact for Questions

Stephen Klaine (sklaine@clemson.edu)