NOTICE: This is the public GitHub repository for the USGS Soil-Water-Balance model. Code found here is under development and may not be suitable for important project work. The official version of the code may be found at: http://wi.water.usgs.gov/Soil_Water_Balance/.
The Soil-Water-Balance (SWB) computer code has been developed to calculate spatial and temporal variations in groundwater recharge. The SWB model calculates recharge by use of commonly available geographic information system (GIS) data layers in combination with tabular climatological data. The code is based on a modified Thornthwaite-Mather soil-water-balance approach, with components of the soil-water balance calculated at a daily timestep. Recharge calculations are made on a rectangular grid of computational elements that may be easily imported into a regional groundwater-flow model. Recharge estimates calculated by the code may be output as daily, monthly, or annual values.
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