FLOOD10485

• County: Arapahoe
• County: Douglas
• Stream Name: Big Dry Creek
• Basin: South Platte
• Title: Big Dry Creek ‎(Arapco)‎ & Tributaries - Major Drainageway Planning - Phase B Preliminary Design Report
• Date: 4/1/1998
• Prepared For: Arapahoe County, Douglas County, Englewood, Greenwood Village, Littleton, UDFCD
• Prepared By: WRC Engineering, Inc.
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

TABLE 111-4
BIG DRY CREEK (ARAPCO)
PEAK RUNOFF COMPARISONS
tOO-YEAR FLOW
WRC FEAM (1975) VTN (1975) WRC (1995)
DESIGN PT LOCA TION (cfs) ( cfs ) ( cfs )
398 S. Platte River 10,700 12,600 8,895
387 Broadway 10,700 12,600 8,878
374 Orchard Road 10,700 12,600 8,491
337 Arapahoe Road 9,200 11,800 6,538
278 Dry Creek Road 9,200 11,800 4,413
240 County Line Road 7,300 10,900 3,558
62+174/176 University Boulevard 7,300 10,900 6,50 I (In)/1,600 (Out)
52 Quarry Road 2,600 3,800 2,115
TABLE 111-5
BIG DRY CREEK (ARAPCO)
PEAK RUNOFF COMPARISONS - NO DETENTION
100- YEAR FLOW
MOST PROBABLE LAND USE
WRC
DESIGN PT LOCATION VTN (1975) WRC (1995)
(cfs) Without
Detention
(cfs)
398 S. Platte River 12,600 11,894
387 Broadway 12,600 11,834
374 Orchard Road 12,600 11,665
337 Arapahoe Road 11,800 10,897
278 Dry Creek Road 11,800 9,684
240 County Line Road 10,900 8,943
62+174/176 University Boulevard 10,900 7,177
52 Quarry Road 3,800 2,115
1-18

BASFL02F.WK3

WRC ENGINEERING, INC.

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23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
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53
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55

TABLE 111-6
SUB-WATERSHED FLOW SUMMARY
MOST PROBABLE DEVELOPMENT
WATERSHED 2-YEAR 5-YEAR O-YEAR 50-YEAR 100-YEAR
DESIGNATION CFS CFS CFS CFS CFS

7
5
10
9
6
5
10
6
8
9
4
7
9
10
9
8
9
12
7
9
5
7
7
5
9
6
16
6
39
24
61
44
31
10
16
55
13
23
41
46
24
43
9
6
7
8
9
6
35
8
5
11
8
50
48

32
24
43
41
27
23
43
25
34
35
17
33
41
43
29
27
30
40
23
36
20
29
30
20
38
25
71
28
88
63
131
92
62
35
51
105
31
45
87
91
50
100
35
27
33
36
28
27
87
37
23
36
27
100
87

45
34
61
58
38
33
62
37
49
50
25
47
58
61
40
38
41
55
33
51
29
41
42
29
54
35
103
40
113
83
169
118
78
49
69
134
41
57
110
117
63
133
49
38
47
52
39
39
113
53
33
50
37
129
110

99
76
138
130
86
74
137
83
107
110
55
103
126
136
86
81
89
117
68
113
64
91
94
64
118
79
219
90
217
166
305
210
144
108
147
235
80
101
206
208
118
254
111
87
109
119
81
87
224
117
73
107
82
230
190

127
98
178
169
112
95
178
108
138
142
72
132
162
176
109
104
116
149
86
146
83
117
120
83
152
103
278
117
270
209
373
257
177
138
189
283
101
123
255
252
146
314
144
114
141
155
104
113
281
151
95
138
105
279
228

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