In South Carolina, sea level rise and sinking land surface means that the coastal areas of the state will experience a relative sea level rise ranging between approximately 0.5 to 1.5 feet in 2030, 0.75 to 3.2 feet in 2050, and 1.75 and 10.8 feet by 2100. These ranges are based on scenarios that encompass uncertainties about physical processes and about future levels of greenhouse gas emissions. They cover low rates of sea level rise and low greenhouse gas emissions to high rates of sea level rise and high greenhouse gas emissions to convey the future risks for the purpose of long-term decision making. Many communities are already experiencing impacts of recurrent flooding, sometimes called nuisance flooding, associated with “king tides” and meteorological events. For the state and county and local governments, sea level rise and increased flooding pose a significant, costly, and persistent threat to roads and highways. These natural disasters and chronic flood damages will inevitably encourage South Carolinians to reconsider the status quo of road maintenance and repair. Under projected sea level rise, repetitive or severe damages will lead to tough decisions about whether to decrease routine maintenance, transfer control of the roads to different government authorities, or abandon existing roads.Although the South Carolina Department of Transportation (SCDOT) owns more than 50% of the roads and highways across the state, adaptation efforts related to road maintenance and abandonment can be expected to occur at both the state and local levels. The state, towns, cities, and counties have legal responsibilities to maintain roads, and they all certainly have an interest in ensuring that roads are safe and maintained. This white paper discusses how South Carolina law may impact local governments that are facing the effects of coastal flooding on their public roadways. The paper first outlines the statutory basis for road ownership and the duties that flow from such ownership. It then reviews potential causes of actions resulting from the breach of duties of maintenance and good repair. Finally, it addresses the procedural requirements for formal road abandonment and takings liability from loss of road access.

Sea level rise and sinking land surface means that the coastal areas in the South Atlantic are very likely to experience a relative sea level rise of one to four feet in the coming century. Many communities are already experiencing impacts of recurrent, sometimes called nuisance flooding, associated with “king tides” and meteorological events. For the state and county and local governments, sea level rise and increased flooding pose a significant, costly, and persistent threat to roads and highways. These natural disasters and chronic flood damages will inevitably encourage decision-makers to reconsider the status quo of road maintenance and repair. Under projected sea level rise, repetitive or severe damages will lead to tough decisions about whether to abandon existing roads, decrease routine maintenance, or transfer control of the roads to different government authorities. To begin to understand the potential scope of the problem, this white paper presents an analysis of roadways in coastal cities and counties in North Carolina, South Carolina, and Georgia vulnerable to sea level rise under one-, two-, and three-foot scenarios, using sea level rise data from NOAA’s Office for Coastal Management Sea Level Rise Viewer Data Download.

This study presents the first comparison of Landsat 8 Operational Land Imager (OLI) and Sentinel-2 Multispectral Instrument (MSI) in identifying soil salinity using soil physiochemical, spectral, statistical, and image analysis techniques. By the end of the century, intermediate sea level rise scenarios project approximately 1.3 meters of sea level rise along the coast of the southeastern United States. One of the most vulnerable areas is Hyde County, North Carolina, where 1140 km(2) of agricultural lands are being salinized, endangering 4,200 people and $40 million USD of property. To determine the best multispectral sensor to map the extent of salinization, this study compared the feasibility of OLI and MSI to estimate electrical conductivity (EC). The EC of field samples were correlated with handheld spectrometer spectra resampled into multispectral sensor bands. Using an iterative ordinary least squares regression, it was found that EC was sensitive to OLI bands 2 (452nm - 512nm) and 4 (636nm - 673nm) and MSI bands 2 (457.5nm - 522.5nm) and 4 (650nm - 680nm). Respectively, the R-Adj(2) and Root Mean Square Error (RMSE) of 0.04-0.54 and 1.15 for OLI, and 0.05-0.67 and 1.17 for MSI, suggests that the two sensors have similar salinity modelling skill. The extracted saline soils make up approximately 1,703hectares for OLI and 118hectares for MSI, indicating overestimation from the OLI image due to its coarser spatial resolution. Additionally, field samples indicate that nearby vegetated land is saline, indicating an underestimation of total impacted land. As sea levels rise, accurately monitoring soil salinization will be critical to protecting coastal agricultural lands. MSI's spatial and temporal resolution makes it superior to OLI for salinity tracking though they have roughly equivalent spectral resolutions. This study demonstrates that visible spectral bands are sensitive to soil salinity with the Blue and Red spectral ranges producing the highest model accuracy; however, the low accuracies for both sensors indicate the need of narrowband sensors. The HyspIRI to be launched in the early 2020s by NASA may provide ideal data source in soil salinity studies.