Retention Pond 24 hour 100-yr Storm values

[bschlang]

I'm designing a retention pond based on Urban Drainage (Colorado Front Range) which requires 1.5 times the 24-hour 100 year storm plus 1 ft freeboard.

I'm familiar using the 1 - 6 hour point rainfall values for varying design storms because it's listed in Urban Drainage. However I don't believe Urban Drainage gives data greater than 6 hour point rainfall values. Is there a way to calculate a 24-hr point rainfall value or do I have to search through a NOAA. Does NOAA categorize there rainfall data in to design storm frequencies (5-yr, 100-yr, etc)?

Thanks for any input.

 

[francesca]

Yes, NOAA does categorize design storm rainfall depths. It's also not hard to find the data you need.

http://hdsc.nws.noaa.gov/hdsc/pfds/index.html