The Control Specifications command allows the user to define when the HEC-HMS hydrology simulation starts and stops, and what computational time interval is to be used in the simulation. Each control specification establishes a time window over which a simulation will be performed. The window is specified using a separate start date, start time, end date, and end time. There is no limit on the length of a time window or the number of simulation time steps it can contain. The time interval defined in the control specification will also be used in displaying time-series results from the simulation.
Follow the steps below to use the Control Specifications command:
The Simulation Time Window section defines the starting date and time and ending date and time of the HEC-HMS hydrology simulation. The user can click on the [Date] button, which displays a calendar date selector from which the user can select a specific date. Similarly, the user can click on the [Time] button, at which point the software displays a 24-hour time selector from which the user can select a specific time.
The Simulation Time Setting section defines the computational time step to be used in the HEC-HMS hydrology simulation.
- From the Analysis ribbon menu, select the Control Specifications command.

- The Control Specifications dialog box will be displayed.

