You can define your IDF curves within StormNET by selecting a hydrology method that uses these (i.e., Rationa Method, etc.) within the Project Options dialog. Then, from the Input Menu, select IDF Curves. The IDF Curves dialog allows you to define the IDF coefficients for various storm frequencies and storm durations. Then, StormNET will automatically select the intensity from the IDF curve from the computed duration for each subbasin.
If you have any additional questions or need any further information, please contact me directly.
Sincerely,
Chris E. Maeder, M.S., P.E.
Senior Technical Engineer
chris.maeder@bossintl.com