Last Modified: 2023-11-08 12:26:29.552

Software Version

HEC-HMS version 4.12 beta 3 was used to create this tutorial. You will need to use HEC-HMS version 4.12 beta 3, or newer, to open the project files.

Project Files

If you are continuing from Creating a New Meteorologic Model, you may continue to your current project files. Otherwise, download the initial project files here:


In this tutorial you will create a control specifications that sets the time window and time interval for a simulation. 


  1. Open the HEC-HMS project named Punxsutawney.
  2. Create a new control specifications: Click on the Components menu and select the Control Specifications Manager option. The manager window will open. Press the New… button to create a new control specifications.
  3. Change the default name (Control 1) to May 1996 and enter a description of Storm of May 1st 1996. Press the Create button to create the new control specifications.
  4. In the Watershed Explorer, click on the control specifications you just created. Enter the correct start and end times in the Component Editor. The start date should be 28Apr1996 at 01:00. The end date should be 04May1996 at 00:00. Select 15 Minutes for the time interval as shown in the figure below.

    Question: The control specifications specify a time interval of 15 minutes. What will happen if precipitation data in the meteorologic model is hourly?

    HEC-HMS will equally distribute the hourly precipitation total over 15 minute intervals. If the hourly total was 1 inch, each 15-minute interval would be 1/4 of an inch.


In this tutorial you control specifications were created that will dictate the duration and time interval of a simulation.

Project Files

Download the final project files here:

Continue to Creating and Computing a Simulation Run