Changes in the Availability of Freshwater along the South Carolina and Georgia Coast due to Potential Climate Change Scenarios
Year: 2012
Type: conference-paper
Abstract: Saltwater intrusion into freshwater aquifers and drainage basins can threaten the biodiversity of freshwater tidal marshes and the contamination of municipal, industrial, and agricultural water supplies (Bear and others, 1999). The balance between hydrological flow conditions within a coastal drainage basin and sea level governs the magnitude, duration, and frequency of salinity intrusion into coastal rivers. Future climate change is likely to aggravate the problems of salinity intrusion in the East Coast of the U.S., as increased air temperatures, changes in regional precipitation regimes, and potential sea-level rise alter these hydrologic balances. This study examines saltwater intrusion at two municipal surface-water intakes on the Atlantic Intracoastal Waterway (AIW) and the Waccamaw River near Myrtle Beach along the Grand Strand of the South Carolina Coast (fig. 1) and illustrates how future sea-level rise and a reduction in streamflows can potentially affect salinity intrusion and threaten the municipal water supply and the biodiversity of freshwater tidal marshes (Furlow and others, 2002). An updated salinity intrusion model of the Pee Dee River Basin (Conrads and Roehl, 2007) was used to evaluate the potential effects of climate change on salinity intrusion. The model was developed using data- mining techniques, including multi-layer perceptron (MLP) artificial neural network (ANN) models (Rosenblatt, 1958; Jensen, 1994). The USGS maintains a real-time streamgaging network of streamflow, water-level and specific conductance recorders in the Pee Dee and Waccamaw River Basins (fig. 1). Streamflow data records exceeding 50 years and specific conductance data records of up to 25 years are available. During the past 25 years of data collection, the estuarine system has experienced various extreme conditions including large 24-hour rainfalls, the passing of tropical systems and major offshore hurricanes, and record drought conditions. The ANN models were developed using data from a subset of this network. The models predict specific conductance at seven coastal gaging stations using data from five upland streamflow recorders, tidal water levels at the north end of the AIW, and wind speed and direction from a coastal meteorological station. The models were validated using historic measurements of specific conductance at selected coastal stream gaging stations. To simulate the effects of sea-level rise, the mean coastal water levels were incremented by 0.5-foot (ft) to simulate sea-level rises of up to 3 ft. To simulate the effect of reduced streamflow to the coast, the daily historical streamflows were reduced by increments of 5 percent to simulate reduction of up to 25 percent. Daily
Source: TigerPrints (Clemson University)
Language: English
Subfield: Environmental Engineering
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W256975607