Societal water-use estimates were required for the other four components of the Coastal Carolinas focus area study. Estimates of water withdrawals related to the societal water use included categories of public supply, self-supplied domestic, industrial, thermoelectric power, irrigation for crops and golf courses, livestock, mining, and aquaculture. Estimates for wastewater returns to surface water bodies were also needed for the surface-water modeling component of the project. These estimates were derived from site-specific data when available or disaggregated from county level information previously published in the USGS series of national water-use reports. These reports were facilitated by the USGS National Water Use Science Project (NWUSP) under the Water Availability and Use Science Program (WAUSP) as part of the National Water Census (NWC) implemented under the SECURE Water Act.
The spatial and temporal compilation of the water-use estimates are dependent on the intended use of the information. Groundwater use estimates were aggregated by MODFLOW model-cell area for the years 2000-2015 and surface-water use and wastewater returns were aggregated by Soil Water Assessment Tool model-catchment area for the years 2000-2014. For the watersheds (HUC8/sub-basin) where the groundwater and surface-water models overlap, estimates were made for those watersheds to satisfy a need for spatial refinements to county scale estimates.
