FLOOD10171

• Designation Number: 218
• County: Boulder
• Community: Unincorporated Boulder County
• Stream Name: Lower Boulder Creek
• Basin: South Platte
• Title: Flood Hazard Area Delineation - Lower Boulder Creek - Valley View Road to Boulder Weld County Line
• Date: 3/1/1983
• Designation Date: 7/1/1983
• Floodplain - Doc Type: Floodplain Report/Masterplan

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FLOODING SOURCE IOO-YEAR FLOODPLAIN DATA FLOODWAY DATA
CReSS IOOyr. DISCHARGE THALWEG FLOODPLAIN FLOODWAY WIDTH Z FLOODWAY
IDENTIFICATION STATION I FLOOD ELEV. (IIIISL)
SECTION (CFS) ELEV. (MSL) WIDTH (FT) LEFT (FTl RIGHT (FT) TOTAL (FT) ELEV. (MSL)
97 856+10 14,200 5125.3 5135.1 3850 * 180 360 540 5135.6
98 864+50 14,300 5128.9 5136.6 3850 * 600 40 640 5137.0
99 869+20 14,300 5131.9 5137.9 3440 * 735 45 780 5138.4
100 874+00 14,350 5133.6 5139.9 2975 *11 960 100 1060 5140.3
101 881+20 14,350 5137.3 5142.6 3570 *.11 1450 80 1530 5143.1
102 885+75 14,400 5138.3 5143.6 2670 II 1400 90 1490 5144.5
103 891+10 14,400 5138.8 5146.1 1775 II 1280 50 1330 5146.9
Fourmile Canyon Creek 104 897+1 0 14,400 5140.5 5149.8 2040 * 350 138 488 5150.1
105 902+60 13,300 5141. 3 5151.6 1045 530 80 610 5152.2
106 909+80 13,300 5141.2 5152.6 1255 1140 86 1226 5153.0
107 915+60 13,300 5141. 8 5153.0 1260 * 1210 30 1240 5153.4
108 922+40 13 ,300 5144.5 5154.0 1965 * 838 10 848 5154.2
109 929+00 13,300 5154.6 5162.5 2240 450 250 700 5162.6
110 934+05 13 ,300 5156.2 5165.2 1250 260 540 800 5165.4
North 66th Street 112 935+00 13,300 5157.7 5167.1 2040 320 630 950 5167.4
113 939+60 13 ,300 5158.6 5167.6 1140 320 560 880 5168.0
114 946+20 13,300 5161.4 5169.3 1610 250 650 900 5169.6
115 954+06 13,300 5165.2 5171. 8 1540 *11 750 150 900 5172.8
116 959+00 13,300 5167.9 5174.1 1700 * 735 135 870 5174.6
117 965+00 13,300 5169.8 5176.7 2190 460 280 740 5177 . 4
South Boulder Creek 118 970+00 13,300 5172.6 5179.5 2140 310 620 930 5180.4 .
119 974+90 (4,800) 5173.7 5181. 2 1850 *11 80 60 800 1060** 700 5182.0
120 983+60 (4,800) 5177 .1 5182.8 1290 II 20 295 315 5183.8
121 990+30 (4,800) 5179.9 5187.5 940 *11 30 20 50 5188.3
122 993+00 (4,800) 5180.9 5191. 2 2250 * 20 28 1365 1620** 303 5192.1
Va1mont Drive 124 994+50 (4,800) 5181.9 5195.4 2990 85 60 1140 1565** 570 5196.0
125 996+90 (2,800) 5183.9 5195.5 1370 II 400 46 446 5196.1
Union Pacific R.R. 127 998+90 (2,800) 5184.9 5195.6 2675 II 700 63 450 1480** 1793 5196.2
128 1005+20 (11,000) 5187.2 5196.5 2600 *11+ 370 910 1280 5197.0
Valley View Road 129 1010+50 (11,000) 5189.1 5199.5 2750 *1'. 680 ++ 51 731 5199.9
Upstream Study Limit

;Distance in feet above mouth
From center of channel looking downstream
* Width includes island area(s) and/or other high ground
between outer floodplain boundaries
II Cross Section does not extend to high ground
+ Width measured to I{;. of South Boulder Creek channel
. Width does nDt ioc1ude South Boulder Creek channel

** Split f1oodway; Area between 1st and 2nd numbers not included
++ Floodway limit located 130 feet past end of Cross Section
( ) Discharge represents estimated flow in Cross Section. For
total dischargi' refer to Figure 3 "Discharge Probability
Profiles"

in floodway

Hydrology and Hydraulics completed
by Omaha District Corps of Engineers.

MULLER ENGINEERING COMPANY, INC.
CONSULTING ENGINEERS
1410 VANCE ST., SUITE ~
LAKEWOOD, COl.ORAOO 80215
[phone]

URBAN DRAINAGE AND FLOOD CONTROL DISTRICT

COLORADO WATER CONSERVATION BOARD
BOULDER COUNTY

IOO-YEAR F'LOODPLAIN AND FLOODWAY
REFERENCE DATA
LOWER BOULDER CREEK

TABLE
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