2009-05-19_REVISION - M1980055HR

• Permit No: M1980055HR
• IBM Index Class Name: REVISION
• Doc Date: 5/19/2009
• Doc Name: EPP ‎(AM-01)‎ Att. P: Drainage; Att. Q: SWMP Repair; Att. R: Rock & Soil Characterization ‎(part 10)‎
• From: Denison Mines
• To: DRMS
• Type & Sequence: AM1
• Email Name: RCO
• Media Type: D
• Archive: No

Table 1. Regional flood frequency equations, Colorado
. discharge
[Q
in cubic feet per seco nd; A
drainage area
in s
uare miles
P l
i
i
i
i
i
h
,
,
,
,
q
;
, mean annua
prec
p
tat
on,
n
nc
es; S, mean drainage-basin slope, in foot per foot]
Recurrence Interval, Standard error Average standard
in years Regression equation of the model, error of prediction,
in percent in percent
Mountain region
2 Q =11.0 (A) 0.663 (S+ 1.0) 3.465 58.5 59.6
5 Q= 17.9 (A) 0.677 (S+ 1.0) 2.739 47.7 48.6
10 Q = 23.0 (A) 0.685 (S+ 1.0) 2.364 43.7 44.6
25 Q = 29.4 (A) 0.695 (S + 1.0) 2.004 41.4 42.3
50 Q= 34.5 (A) 0.700 (S+ 1.0)1.768 41.4 42.3
100 Q = 39.5 (A) 0.706 (S+ 1.0) 1.577 42.4 43.4
200 Q= 44.6 (A) 0.710 (S+ 1.0) 1.408 44.2 45.2
500 Q = 51.5 (A) 0.715 (S+ 1.0) 1.209 47.5 48.6
Rio Grande region
2 Q = 0.03 (A) 0.979 (p) 1.615 77.7 82.6
5 Q = 0.12 (A) 0.940 (P) 1.384 64.0 67.9
10 Q = 0.25 (A) 0.914 (P) 1.277 58.2 61.9
25 Q = 0.52 (A) 0.884 (P) 1.117 53.4 56.8
50 Q = 0.81 (A) 0.864 (P) 1.121 51.2 54.5
100 Q = 1.19 (A) 0.846 (p) 1.074 49.9 53.3
200 Q =1.67 (A) 0.828 (p) 1.036 49.5 52.9
500 Q = 2.48 (A) 0.808 (p) 0.995 50.0 53.6
Southwest region
2 Q= 28.7 (A) 0.699 85.0 87.3
• 5 Q = 50.5 (A) 0.693 74.1 76.1
10 Q = 66.0 (A) 0697 71.4 73.4
25 Q = 86.3 (A) 0.704 71.2 73.4
50 Q = 102.0 (A) 0.709 72.8 75.0
100 Q= 118.4 (A) 0.715 75.6 78.0
200 Q = 135.5 (A) 0.720 79.1 81.7
500 Q= 159A (A) 0.728 85.0 87.9
Northwest region
2 Q = 0.39 (A) 0.684 (p) 1.304 82.6 85.6
5 Q= 2.84 (A) 0.674 (p) 0.833 71.5 74.0
10 Q = 7.56 (A) 0.671 (P) 0.601 68.5 70.9
25 Q = 20.6 (A) 0.669 (p) 0.362 67,1 69.7
50 Q= 38.8 (A) 0.667 (P) 0210 67.2 69.8
100 Q =104.7 (A) 0.624 75.0 76.7
200 Q =118.5 (A) 0.624 77.8 79.6
500 Q= 137.6 (A) 0.623 83,1 85.1
Plains region
2 Q = 39.0 (A) 0.486 234 258
5 Q= 195.8 (A) 0.399 204 224
10 Q = 364.6 (A) 0.400 212 234
25 Q = 725.3 (A) 0.395 232
256
50 Q=1116 (A) 0.392 250
278
100 Q=1640 (A) 0.388 267 300
200 Q= 2324 (A) 0.385 284 321
500 Q = 3534 (A) 0.380 306 348

ESTIMATING MAGNITUDE OF PEAK DISCHARGES 9