The Storage package is used to specify the storage properties of cells in MODFLOW 6 transient models. The STO: Storage Package pane is on the MODFLOW Packages and Programs dialog box under Flow Packages. The Storage package is required if a model is transient. A model is transient if it has at least one transient stress period as defined in the MODFLOW Time dialog box.
The user must specify whether the confined storage properties will be specified using specific storage or the storage coefficient. (The storage coefficient is the specific storage times the layer height.) In the latter case, the "Confined_Storage_Coefficent" data set will be exported to the Storage package input file.