From: Markus Ritsch [MLRitsch@water-and-earth.com]
Sent: Sunday, August 03, 2008 3:00 PM
To: Kevin Stewart; Chad Kudym
Cc: Markus Ritsch
Subject: Re: July 2008 Peak Rainfall Intensity-Duration Amounts
Kevin,
 
This was pretty interesting.  Although July was a dry month, there was an unusually strong storm on July 6 between 2:30 PM and 3:00 PM to the east of Denver.
The Murphy Creek Golf Course (ID 870) had short duration rainfall intensity that exceeded the 100-year values for the 10 and 15 minute periods (see the tables below).
 
Why did I not see sensor 830 and sensor 2930 in the rainfall rate alarm log file?  These two stations also had high intensity short duration rainfall.
 
Let me know if you have any questions regarding the analysis or if you need more data/analysis from me.
 
Thanks,
Markus
 
 
 
5 Minute Peak Intensities
Station Date Tips Inches in/hr Return
870 7/6/08 2:46 PM 17 0.669 8.031 < 100-yr
830 7/6/08 2:40 PM 11 0.433 5.197 10-year
2930 7/18/08 7:04 PM 10 0.394 4.724 < 10-yr
730 7/6/08 2:29 PM 9 0.354 4.252 < 10-yr
 
10 Minute Peak Intensities
Station Date Tips Inches in/hr Return
870 7/6/08 2:51 PM 31 1.220 7.323 > 100-yr
730 7/6/08 3:05 PM 15 0.591 3.543 5-yr
2930 7/18/08 7:08 PM 14 0.551 3.307 5-yr
830 7/6/08 2:40 PM 12 0.472 2.835 > 2-yr
 
15 Minute Peak Intensities
Station Date Tips Inches in/hr Return
870 7/6/08 2:51 PM 40 1.575 6.299 > 100-yr
730 7/6/08 2:30 PM 20 0.787 3.150 5-yr
2930 7/18/08 7:11 PM 16 0.630 2.520 5-yr
 
 
30 Minute Peak Intensities
Station Date Tips Inches in/hr Return
870 7/6/08 2:54 PM 44 1.732 3.465 25-yr
730 7/6/08 2:30 PM 22 0.866 1.732 > 2-yr
2930 7/18/08 7:15 PM 17 0.669 1.339 < 2-yr
 
1 Hour Peak Intensities
Station Date Tips Inches Return
870 7/6/08 3:18 PM 46 1.811 > 10-yr
730 7/6/08 3:12 PM 42 1.654 > 10-yr
 
Markus Ritsch, P.E.
Water & Earth Technologies, Inc.
1225 Red Cedar Circle, Suite A
Fort Collins, CO 80524
 
Tel: (970) 225-6080
Fax: (970) 225-6990