An existing three-dimensional model (MODFLOW-2000) by Petkewich and Campbell (2007) (https://pubs.usgs.gov/sir/2007/5126/) was updated to simulate six predictive water-management scenarios that were created to simulate potential changes in groundwater flow and groundwater-level conditions in the Mount Pleasant, South Carolina area. The model was recalibrated to conditions from 1900 to 2015. Simulations included six scenarios:

(1) maximize Mount Pleasant Waterworks reverse-osmosis plant capacity by increasing groundwater withdrawals from 3.9 million gallons per day (Mgal/d) in 2015 to 8.6 Mgal/d from the Middendorf aquifer;

(2) same as Scenario 1, but with the addition of a 0.5 Mgal/d supply well in the Middendorf aquifer near Moncks Corner, SC;

(3) same as Scenario 1, but with the addition of a 1.5 Mgal/d supply well in the Middendorf aquifer near Moncks Corner, SC;

(4) maximize Mount Pleasant Waterworks well capacity by increasing withdrawals from the Middendorf aquifer from 3.9 Mgal/d in 2015 to 10.2 Mgal/d

(5) minimizing Mount Pleasant Waterworks surface-water purchase from the Charleston Water System by adding supply wells and increasing withdrawals from the Middendorf aquifer from 3.9 Mgal/d in 2015 to 12.2 Mgal/d; and

(6) same as Scenario 1, but with the addition of quarterly model stress periods to simulate seasonal variations in the groundwater withdrawals. This USGS data release contains all of the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20175128).