FLOOD09322

• County: Rio Blanco
• Community: Rangely
• Stream Name: White River
• Basin: Yampa/White
• Title: White River at Rangely
• Date: 10/1/1993
• Prepared For: Rangely
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Floodplain Report/Masterplan

cross sections. The maximum difference was slightly more .than one-
tenth of a foot at cross section 58, which is located upstream from
and out.side of the area of this study. Most of the differences
were thought to result from the use ()f a later version of HEC-2 for
the current study. Table 2 givel; the computed 100--YE!ar flood
water s'urface elevations (in fee.t,. mean sea level (m.s..l.)) from
the FIS and from the restored file between cross sections 33.2 and
46.0 (in the study area).

Table 2
100-Year Flood Water Surface Elevations
from FIS and RI~st()red File

Cross section

Computed 100-Year Water Surface
Ele,vations (in feet m.s.l...),
FIS,-FiJ,e Restored Filp"

3:,.2
310.0
3~'. 0
3!i.0
39.0
40.0
4:.. 0
4~~ . 0
43.0
4'1.0
4!,.0
41,.0
4-'.0

5204.59
5205.57
5205.75
5206.05
5207.63
5209.08
5210.32
5211. 73
5212.97
5214.14
5215.73
5218.33
5219.35

5204.59
5205.57
5205.75
5206.06
5207.63
5209.08
5210.32
5211. 73
5212.97
5214.13
5215.70
5218.34
5219.34

Hvdrau:,ic Analvsis of Existinq Levees.

The existing levee along the Whi"te River consists of' two main
sections, each constructed at different times. ThE! original
section of the levee runs along th,e rive,rbank near the old water
filtra1:ion plant. The section added in 1986 runs to the north and
west f]:om the end of the original levee and cuts across the large
bend of the White River. For t:he NFIP to recognize a levee as
providing flood protection, it mus"t meet certain criteria and be
certif,Led. The requirements of the NFIP for levees are described
in more detail in a later section of this report. The existing
levee~t Rangely is not c:ertifiE!d and is not officially credited
wi th p::oviding flood protection.

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