A water balance (or water budget) like the one shown in Figure 26 reveals the amount of water moving into and out of the system (recall that, in the basic model, aquifer recharge is balanced by surface seepage). A water balance is automatically created for the model domain every time a model is submitted for simulation. Positive fluxes represent sources of water to the zone/domain, while negative fluxes represent sinks of water.
If you click the chevron of the Water Balance chart, you will see that water balance analyses can be conducted not only for the model domain, but also for any zone added to the model domain (see Flow Properties tab of the Zone Attributes menu) or a single grid cell of the model. You will also see that default units are cubic feet per second (CFS), but users can change the units to gallons per minute (GPM) or cubic meters per day (m3/day) by using the drop-down menu next to ‘Unit’. Any changes made require that the ReDraw button is selected before the chart is updated.