NOAA Atlas 14 - precipitation intensity
NOAA Atlas 14 - precipitation intensity
(OP)
I normally work in really large drainage areas, so I may be overthinking this...
I have a small site, less than 5 acres. I need to calculate pre-post project stormwater calcs.
My plan is to use rational equation and use NOAA Atlas 14 for precipitation intensity (I) in the equation. Looking at the in/hr values in the table, it seems like the discharges are really small. Am I missing something?
I have a small site, less than 5 acres. I need to calculate pre-post project stormwater calcs.
My plan is to use rational equation and use NOAA Atlas 14 for precipitation intensity (I) in the equation. Looking at the in/hr values in the table, it seems like the discharges are really small. Am I missing something?
RE: NOAA Atlas 14 - precipitation intensity
your Tc is probably 10 minutes, so you should be seeing some fairly high intensities
make sure you are looking at intensity and not depth ("data type" at the top of the screen)
RE: NOAA Atlas 14 - precipitation intensity
Yes, I am using the precipitation estimates.
RE: NOAA Atlas 14 - precipitation intensity
say you are in Sedgewick Kansas
time of concentration is 10 minutes for your site
25-year, 10-minute rainfall intensity is 6.89 inch/hour
Q=CIA will give the peak discharge
Rational method doesn't use the total storm duration to determine peak discharge
RE: NOAA Atlas 14 - precipitation intensity
Peter Smart
HydroCAD Software
www.hydrocad.net
RE: NOAA Atlas 14 - precipitation intensity
RE: NOAA Atlas 14 - precipitation intensity