Does anyone know why the "Time steps" fields in the Analysis Options and the "Impervious/Pervious area" fields in the Subbasins Physical properties Dialog boxes are deactivated/grayed out after the first execution of an SSA model?
What if I decide that the Time steps and or the Impervious area of a subbasin need to be adjusted after the model is executed? What then? Would I have to re-enter the entire model again? This seems counter-intuitive, and it defeats the purpose of putting a model together in the first place.
In SSA, the routing time steps and "Impervious/Pervious area" fields in the Subbasins Physical properties Dialog boxes are deactivated/grayed out by default if Rational, Modified Rational and DeKalb Rational Methods are used as the Hydrology method.
The program uses 10 seconds as the default routing time steps. The code is written so that a range of Tc values would determine the time step.
The Impervious/Pervious area fields are grayed out and instead Runoff Coeffiecient fields will be activated, since these parameters are not used in Rational methods, they will be activated once you select other hydrology methods such as EPA SWMM and SCS methods that require the impervious and pervious criterias.
If my post answers your question, please mark it as an Accepted Solution, so that others can find answers quickly!