Hydraflow Storm Sewer - TR-55 Tc Worksheet

[cattjake]

Good afternoon.

I have never used the Hydraflow storm sewer before but currently have a complex system to design.

I was wondering about the tr-55 tc worksheet for a grate inlet

Is this flow information leading from the drainage area to that particular inlet?

Also, how do you change the tc from a two-yr 24-hr rain to the 25 year 24hr?

Thanks,

[wfberry]

The Tc is Time of Concentration.  The time it takes for a "drop of water" to flow from the most distance area in drainage shed to its' outlet.  Hence, there is no difference.

Bill