thread162-321197
"As indicated by psmart, the Tc is very small (less than 5 minutes). Thoughb the municipality expressed that it would be up to the engineer to choose a rainfall duration for design. I guess I should choose a standard duration but I do not know what that standard would be."
The OP indicates a small site since the Tc is "less than 5 minutes". It is common industry practice to simply use the Modified Rational Method to approximate a reasonable runoff volume for the needs of a small site.
"As indicated by psmart, the Tc is very small (less than 5 minutes). Thoughb the municipality expressed that it would be up to the engineer to choose a rainfall duration for design. I guess I should choose a standard duration but I do not know what that standard would be."
The OP indicates a small site since the Tc is "less than 5 minutes". It is common industry practice to simply use the Modified Rational Method to approximate a reasonable runoff volume for the needs of a small site.