The U.S. Geological Survey, in cooperation with Wake County Environmental Services, initiated a comprehensive groundwater resource investigation to better understand the quantity and quality of groundwater in Wake County, North Carolina. In 2020, as part of the investigation, groundwater records were compiled electronically from 7,689 wells in and within five miles of Wake County and groundwater yield data was interpolated to estimate maximum well yield across the county. Maximum well yield values estimate the maximum well yield possible at a given location; the maximum well yield is not guaranteed and actual well yield likely falls within the range of 0 and the maximum well yield value. This data release includes the well record compilation (well_inventory.csv) and estimated raster surface of maximum well yield (max_well_yield.zip). The well inventory includes the characteristics: well location, well depth, casing depth, and well yield. The data contained in this data release and the methodology for development of the maximum well yield raster is further described in the associated U.S. Geological Survey Scientific Investigations Report (https://doi.org/10.3133/sir20225041).

As part of a collaborative study with the City of Raleigh, North Carolina, the U.S. Geological Survey developed a drainage network for the Greater Raleigh Area, North Carolina using the most recent available lidar data, representing the years 2015 and 2022. This dataset includes the delineated drainage network (drainage_network.zip) and rasters representing the breached and filled digital elevation model (raleigh_dem_fil.tif), the flow accumulation raster (raleigh_d8_fac.tif), and the flow direction raster (raleigh_d8_fdr.tif). Raster files are available as Cloud Optimized GeoTIFFs, meaning they are formatted to work on the cloud or can be directly downloaded. The drainage network was delineated for all locations with an upstream drainage area greater than 0.075 square kilometers (approximately 18.5 acres) and represents perennial streams, ephemeral streams, ditches, stream buried in pipes, and artificial paths through water bodies. This dataset was developed for use in the development of a model that can remotely predict streambank erosion potential along streams in the Greater Raleigh, NC Area. However, the drainage network and supporting raster files have the potential to be used in numerous applications including watershed delineation.

As part of a collaborative study with the City of Raleigh, North Carolina, the U.S. Geological Survey developed a drainage network for the Greater Raleigh Area, North Carolina using the most recent available lidar data, representing the years 2015 and 2022. This dataset includes the delineated drainage network (drainage_network.zip) and rasters representing the breached and filled digital elevation model (raleigh_dem_fil.tif), the flow accumulation raster (raleigh_d8_fac.tif), and the flow direction raster (raleigh_d8_fdr.tif). Raster files are available as Cloud Optimized GeoTIFFs, meaning they are formatted to work on the cloud or can be directly downloaded. The drainage network was delineated for all locations with an upstream drainage area greater than 0.075 square kilometers (approximately 18.5 acres) and represents perennial streams, ephemeral streams, ditches, stream buried in pipes, and artificial paths through water bodies. This dataset was developed for use in the development of a model that can remotely predict streambank erosion potential along streams in the Greater Raleigh, NC Area. However, the drainage network and supporting raster files have the potential to be used in numerous applications including watershed delineation.

A Soil-Water-Balance (SWB) model was developed to estimate annual net infiltration below the root-zone for the Greater Wake County area, North Carolina for the period 1981 through 2019. The model was developed as part of a study to assess groundwater availability in the fractured-rock aquifers underlying Wake County. Curve number, maximum net infiltration rate, and root-zone depth parameters for all land cover classes were adjusted in the SWB model to manually test parameter sensitivity and adjust for best fit. Annual net infiltration estimates from the SWB model were also compared with annual base flow estimates from the PART hydrograph separation technique using the USGS Groundwater Toolbox (Barlow and others, 2015) for available years of streamflow record at 6 sites within the model area (02089000, 02087570, 02087324, 02087359, 02088500, 02097314), as base flow is assumed to be nearly equivalent to effective groundwater recharge (Nelms and others, 1997). This USGS data release contains all the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20225041), as well as model output comparisons with base flow estimates. Also included in this data release is the map of hydrogeologic units in Wake County used in this study.

A Soil-Water-Balance (SWB) model was developed to estimate annual net infiltration below the root-zone for the Greater Wake County area, North Carolina for the period 1981 through 2019. The model was developed as part of a study to assess groundwater availability in the fractured-rock aquifers underlying Wake County. Curve number, maximum net infiltration rate, and root-zone depth parameters for all land cover classes were adjusted in the SWB model to manually test parameter sensitivity and adjust for best fit. Annual net infiltration estimates from the SWB model were also compared with annual base flow estimates from the PART hydrograph separation technique using the USGS Groundwater Toolbox (Barlow and others, 2015) for available years of streamflow record at 6 sites within the model area (02089000, 02087570, 02087324, 02087359, 02088500, 02097314), as base flow is assumed to be nearly equivalent to effective groundwater recharge (Nelms and others, 1997). This USGS data release contains all the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20225041), as well as model output comparisons with base flow estimates. Also included in this data release is the map of hydrogeologic units in Wake County used in this study.

The U.S. Geological Survey and a consortium of local governments in North Carolina have partnered together to track water quality and quantity conditions in several of the area’s water-supply reservoirs and streams, known as the Triangle Area Water Supply Monitoring Project (TAWSMP). This data release contains the associated data described in the Open-File Report, "Triangle Area Water Supply Monitoring Project, North Carolina-Overview of Hydrologic and Water-Quality Monitoring Activities and Data Quality Assurance". These datasets were collected during October 2019 - September 2022 (Water Years 2020-2022). The data release includes nine items: 1. [Triangle_2020_22_Figure_1.pdf]: This figure shows site locations and types of water-quality sampling activities at each site. 2. [readme_Triangle_2020_22.pdf]: This document summarizes the sampling phase(s) of the TAWSMP and reports additional details for which the current data release covers. 3. [Triangle_2020_22_Table_1.csv]: This file contains all relevant site information for the water quality and streamflow monitoring network. 4. [Triangle_2020_22_Table_2.csv]: This file provides details on the physical properties or constituents that are monitored and their analytical methods. 5. [Triangle_2020_22_Table_3.csv]: This file contains a summary of the environmental sample results, including numbers of samples and ranges of concentrations, for each site. 6. [Triangle_2020_22_Table_4.csv]: This file provides the analytical results of field blanks, equipment blanks, and sampling-vehicle (ambient) blanks. 7. [Triangle_2020_22_Table_5.csv]: This file shows a summary of selected constituent data observed in blank and environmental samples. 8. [Triangle_2020_22_Table_6.csv]: This file provides environmental sample data, the corresponding replicate sample data, and the relative percent differences. 9. [Triangle_2020_22_Table_7.csv]: This file contains the analytical results for each environmental water-quality sample.

These datasets contain information used to compile the report (USGS OFR 2016-1137). It contains water-quality data, analytical results of field blanks, and analytical results for environmental and replicate sample sets for surface-water samples collected during water years 2012 and 2013 for the Triangle Area Water Supply Monitoring Program (TAWSMP). The water-quality data contained in appendix 1 are field paramters and the analytical results for the constituents analyzed for the project. Appendix 2 contains the results of the field blanks, and the results for the environmental and replicate sample sets are presented in appendix 3.

This U.S. Geological Survey Data Release contains the associated data described in the Scientific Investigations Report, "Trends in water quality of selected streams and reservoirs used for water supply in the Triangle area of North Carolina, 1989-2013". Since 1989, the U.S. Geological Survey and a consortium of local governments have tracked water-quality conditions and trends in the water-supply reservoirs and streams in the Triangle area of North Carolina located within the upper Cape Fear and Neuse River Basins. Temporal trends in water-quality were analyzed for thirteen stream and eight reservoir sites. Seventeen water-quality parameters and constituents were examined at these sites.

This U.S. Geological Survey Data Release contains the associated data described in the Scientific Investigations Report, "Trends in water quality of selected streams and reservoirs used for water supply in the Triangle area of North Carolina, 1989-2013". Since 1989, the U.S. Geological Survey and a consortium of local governments have tracked water-quality conditions and trends in the water-supply reservoirs and streams in the Triangle area of North Carolina located within the upper Cape Fear and Neuse River Basins. Temporal trends in water-quality were analyzed for thirteen stream and eight reservoir sites. Seventeen water-quality parameters and constituents were examined at these sites.

This U.S. Geological Survey Data Release contains the associated data described in the Scientific Investigations Report, "Trends in water quality of selected streams and reservoirs used for water supply in the Triangle area of North Carolina, 1989-2013". Since 1989, the U.S. Geological Survey and a consortium of local governments have tracked water-quality conditions and trends in the water-supply reservoirs and streams in the Triangle area of North Carolina located within the upper Cape Fear and Neuse River Basins. Temporal trends in water-quality were analyzed for thirteen stream and eight reservoir sites. Seventeen water-quality parameters and constituents were examined at these sites.