IDF A,B,C Coefficients vs SCS Storm Distribution
IDF A,B,C Coefficients vs SCS Storm Distribution
(OP)
Hello All,
I recently had a conversation with a colleague of mine regarding converting rainfall intensities from A,B C coefficients of the rational method to rainfall depths to further generate a SCS storm distribution.
I had never heard of this before and I would question the accuracy of doing so..however, I wanted to open up a discussion see if....
1) Is this possible?
2) If yes, where could I find referece material?
3) Are there limitations and/or concerns of doing this?
Thank you in advance. Any help in this matter would be greatly appreciated.
I recently had a conversation with a colleague of mine regarding converting rainfall intensities from A,B C coefficients of the rational method to rainfall depths to further generate a SCS storm distribution.
I had never heard of this before and I would question the accuracy of doing so..however, I wanted to open up a discussion see if....
1) Is this possible?
2) If yes, where could I find referece material?
3) Are there limitations and/or concerns of doing this?
Thank you in advance. Any help in this matter would be greatly appreciated.





RE: IDF A,B,C Coefficients vs SCS Storm Distribution
The applicability of a Chicago-style storm is generally specified by the local stormwater regulations.
Peter Smart
HydroCAD Software
www.hydrocad.net
RE: IDF A,B,C Coefficients vs SCS Storm Distribution
Yes agreed, however, would it be possible to create, for example a 100-year Chicago storm to a 100-year SCS?
My thoughts would be you would have to do a bit of math to break down the Chicago storm into unit intervals to be determine a total rainfall depth and then apply to the SCS distribution? Could you do this?
RE: IDF A,B,C Coefficients vs SCS Storm Distribution
Regardless of the origin of the mass curve, you can evaluate the IDF data for a duration of 24-hours to get a total depth for use with any of the mass curves. There's no need to "break down the Chicago storm". Just evaluate the 24-hour depth directly from the IDF coefficients.
Peter Smart
HydroCAD Software
www.hydrocad.net
RE: IDF A,B,C Coefficients vs SCS Storm Distribution