A new version of previously published steady-state numerical groundwater flow models of the Great Basin carbonate and alluvial aquifer system (GBCAAS), and was developed in conjunction with U.S. Geological Survey (USGS) studies in Parowan, Pine, and Wah Wah Valleys, Utah. This version of the model is considered to be GBCAAS v. 3.0 and supersedes previous versions. This model added 15 transient calibration stress periods and 14 projection stress periods, aquifer storage properties, historical withdrawals in Parowan Valley, and observations of water-level changes in Parowan Valley to the previous steady-state versions. Recharge in Parowan Valley and withdrawal from wells in Parowan Valley and two nearby wells in Cedar City Valley vary for each calibration stress period representing conditions from March 1940 to November 2013. Stresses, including recharge, are the same in each stress period as in the steady-state stress period for all areas outside of Parowan Valley. This data release contains one calibration simulation and one projection simulation. The model is calibrated to transient conditions only in Parowan Valley. Simulated storage properties outside of Parowan Valley are set the same as the Parowan Valley properties and should not be considered calibrated. The projection simulation was used to estimate that reducing withdrawals in Parowan Valley from 35,000 to about 22,000 acre-feet per year should stabilize groundwater levels in the valley if recharge varies as it did from about 1950 to 2012 and that withdrawals of 15,000 acre-feet per year from Pine Valley and 6,500 acre-feet per year from Wah Wah Valley could ultimately (long-term steady-state) cause water-level declines of about 1,900 feet near the withdrawal wells and more than 5 feet over about 10,500 square miles. 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/sir20175072). This data release also contains source code needed to run the models. Model files presented in this data release were modified from an existing, calibrated, steady-state model of the Great Basin carbonate and alluvial aquifer system. SIR 2014-5213 (https://pubs.usgs.gov/sir/2014/5213/) and SIR 2017-5011 (https://doi.org/10.3133/sir20175011) document the construction and calibration of the previous versions of this model. Modifications that were made to the input files and discussion of model results are documented in SIR2017-5072 (https://doi.org/10.3133/sir20175072), which is associated with this data release. The model consists of a parent and a child model and must be run using MODFLOW-LGR. The child model is far removed from the area considered for this project, but is being kept with the model so that one model version exists of the Great Basin carbonate and alluvial aquifer system that incorporates all refinements and improvements. The model files documented in this data release should be used instead of previous versions.