In cooperation with the South Carolina Department of Transportation, the U.S. Geological Survey updated the foundational geospatial layers for the South Carolina StreamStats web application (https://water.usgs.gov/osw/streamstats/), which provides analytical tools useful for water-resources planning and management (Kolb and others, 2018). This dataset presents the digital elevation model, lidar-derived flow direction, flow accumulation, and percent basin slope raster data layers used for analysis in StreamStats. It also includes the streamline vector data used to hydro-enforce the raster data layers.

This dataset contains an inventory of South Carolina U.S. Geological Survey (USGS) streamgages evaluated in 2017 as part of gage network gap assessment. Both continuous record and crest stage gages are included in this dataset. The data are grouped into three categories: rural streamgages with equal to or greater than 10 years of peak-flow data, rural streamgages with less than 10 years of peak-flow data, and urban streamgages.

In cooperation with the South Carolina Department of Transportation (SCDOT), the U.S. Geological Survey prepared geospatial layers illustrating the boundaries of the regions used in the South Carolina (SC) Stream Hydrograph Methods presented in Bohman (1990, 1992). The region limits were described in written text and depicted in figures in Bohman (1990,1992), but have not been provided as geospatial layers (due to the age of the original publications). This project used best-available geospatial data from the U.S. Environmental Protection Agency (USEPA) ecoregions (2013) to create equivalent geospatial representations of the Bohman (1990, 1992) region boundaries for the SC Stream Hydrograph Methods. These layers will be used in the SC StreamStats application to generate hydrographs for estimated storm runoff simulations. The StreamStats application (https://streamstats.usgs.gov) provides access to spatial analytical tools that are useful for water-resources planning and management, and for engineering and design purposes. The map-based user interface can be used to delineate watershed areas, retrieve basin characteristics, estimates of flow statistics, and more.

This dataset was produced by the US Geological Survey as a supporting dataset to be used for the purpose of calculating stream gage basin characteristics in preparation for the South Carolina StreamStats application. This integer raster dataset represents runoff curve numbers for the combinations of hydrological soils groupings and land cover types within the South Carolina StreamStats study area. Soils data were from the USDA, NRCS SSURGO soils database and land cover data are USGS 2019 NLCD data. The dataset will be used in peak flow regression equations that are used to predict flow in South Carolina streams. The StreamStats application provides access to spatial analytical tools that are useful for water-resources planning and management, and for engineering and design purposes. The map-based user interface of StreamStats can be used to delineate drainage areas, get basin characteristics, estimates of flow statistics, and more. Inventory of data release: SC_RCN_LU_CO.tiff (1 .tif file): Cloud optimized GeoTIFF containing integer rasters that are runoff curve numbers for soils/land cover combinations

Reliable peak-streamflow information is critical for proper design of stream-related infrastructure, such as bridges, and StreamStats is a Web-based Geographic Information Systems (GIS) application that provides a user-friendly interface to estimate peak flows (https://streamstats.usgs.gov/ss/). StreamStats develops these peak-flow estimates using basin characteristics for the entire contributing area to a user-selected point; however, infrastructure planners often need to estimate flows for an area downstream from a known control such as a reservoir release or a weir. This dataset was compiled in cooperation with the South Carolina Department of Transportation (SCDOT) to provide a GIS layer of filtered regulation points from the U.S. Army Corps Engineers (USACE) National Inventory of Dams and upstream basin polygons for those points, for use within the South Carolina StreamStats client application. A select few characteristics were computed for each basin in the polygon dataset to enable the application to estimate flows above and below each regulation point and better assist SCDOT personnel when designing new or revising existing stream-related infrastructure.

In cooperation with the South Carolina Department of Transportation, the U.S. Geological Survey calculated four land cover basin characteristics rasters as part of preparing the South Carolina StreamStats 2021 application. These datasets are raster representations of impervious surface, developed, forested, and storage land cover attributes within the South Carolina StreamStats 2021 study area, and will be served in the South Carolina StreamStats 2021 application to describe delineated watersheds. The StreamStats application provides access to spatial analytical tools that are useful for water-resources planning and management, and for engineering and design purposes. The map-based user interface can be used to delineate watershed areas, get basin characteristics and estimates of flow statistics, and more.

In cooperation with the South Carolina Department of Transportation, the U.S. Geological Survey developed a StreamStats web application (https://water.usgs.gov/osw/streamstats/) that provides analytical tools for water-resources planning and management (Ries and others, 2017). This data set presents the lidar-derived flow direction, flow accumulation, streamline, and hydro-enforced digital elevation model raster data used for analysis in StreamStats. Rasters are included for each of the following hydrologic unit codes (HUCs): 03040101, 03040102, 03040103, 03040104, 03040105, 03040201, 03040202, 03040203, 03040204, 03040205, 03040206, 03040207, 03040208, 03050101, 03050102, 03050103, 03050104, 03050105, 03050106, 03050107, 03050108, 03050109, 03050110, 03050111, 03050112, 03050201, 03050202, 03050203, 03050204, 03050205, 03050206, 03050207, 03050208, 03050209, 03050210, 03060101, 03060102, 03060103, 03060104, 03060105, 03060106, 03060107, 03060108, 03060109, and 03060110. The raster data is organized into four main zip folders, which are called “Flow_Accumulation_Grids,” “Flow_Direction_Grids,” Hydro_Enforced_DEM_Grids,” and “Streamline_Grids.” Reference: Ries, K.G., III, Newson J.K., Smith, M.J., Guthrie, J.D., Steeves, P.A., Haluska, T.L., Kolb, K.R., Thompson, R.F., Santoro, R.D., and Vraga, H.W., 2017, StreamStats, version 4: U.S. Geological Survey Fact Sheet 2017–3046, 4 p., https://doi.org/10.3133/fs20173046.

In cooperation with the South Carolina Department of Transportation, the U.S. Geological Survey calculated four land cover basin characteristics rasters from the National Land Cover Database (NLCD) 2019 as part of updating the South Carolina StreamStats application. These datasets are raster representations of impervious surface, developed, forested, and storage land cover attributes within the South Carolina StreamStats study area, and will be served in the South Carolina StreamStats application to describe delineated watersheds. The StreamStats application provides access to spatial analytical tools that are useful for water-resources planning and management, and for engineering and design purposes. The map-based user interface can be used to delineate watershed areas, get basin characteristics and estimates of flow statistics, and more.

Reliable estimates of the magnitude and frequency of floods are an important part of the framework for hydraulic-structure design and flood-plain management in Georgia, South Carolina, and North Carolina (study area). Annual peak flows measured at U.S. Geological Survey streamgages were used to compute at-site flood-frequency estimates at those streamgages in the study area based on annual peak-flows records through 2017. Flood-frequency estimates also are needed at ungaged stream locations. A process known as regionalization was used to develop regression equations to estimate the magnitude and frequency of floods at ungaged locations. This model archive provides the inputs and outputs for (1) the at-site flood-frequency statistics and (2) the regression models developed to allow for estimation of flood-frequency statistics at ungaged stream locations in the study area. The inputs and outputs for the at-site flood-frequency statistics are provided under the SAWSC PeakFQ input and output files for at-site flood-frequency statistics child item. The inputs and outputs for the regression models are provided under the SAWSC rural flood-frequency regression models (R scripts and applications) child item. Further details concerning the inputs and outputs are provided within the metadata and ReadMe files underneath each child item within this data release. Information describing the contents of this model archive is provided below in a text-based file attached to the front landing page for this data release.

Reliable estimates of the magnitude and frequency of floods are an important part of the framework for hydraulic-structure design and flood-plain management. Annual peak flows measured at U.S. Geological Survey streamgages are used to compute flood-frequency estimates at those streamgages. However, flood-frequency estimates also are needed at ungaged stream locations. A process known as regionalization was used to develop regression equations to estimate the magnitude and frequency of floods at ungaged locations. This dataset contains the supporting tables and updated hydrologic region boundaries used in the 2017 flood-frequency study for Georgia, South Carolina, and North Carolina.