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Soil-Water-Balance (SWB) model datasets for the Greater Wake County area, North Carolina, 1981-2019

April 28, 2022

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 (, 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.