FLOOD07429

• Designation Number: 60
• County: Morgan
• Community: Brush
• Stream Name: Beaver Creek
• Basin: South Platte
• Title: Floodplain Information Report - Beaver Creek, Brush, Colorado
• Date: 4/1/1976
• Prepared For: Brush
• Prepared By: Gingery Associates, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

channel area for the lOO-year flood event would be 3 to 4 feet
per second. Average flow velocities in the flood plain west of
th~ main channel, including the downtown area, would average
between 1 to 3 feet per second. The flood plain east of the main
channel would have aver~gc velocities ranging between 1 and 4
feet per second. Flood flow depths would be shallow throughout
the reach, ranging from approximately 0.5 to 1 foot along the
east edge of town to a maximum depth of 4 to 4.5 feet on Clayton
Street.
Between County Road DLD and the Burlington Northern Railroad,
the average flow velocity for the lOO-year flood event in the main
channel would be approximately 2 to 3 feet per second. The fringe
areas of the flood plain would experience average velocities of
1 to 2 feet per second west of the main stream and approximately
0.7 to 1.2 feet per second east of the main stream. Flow depths
in the wide flood plain area west of the creek would average be-
tween 1.5 to 2 feet.
From County Road DLD to the upstream study limits, the main
channel velocities are muc h higher, r~nging from 6 to 10 feet per
second. Through the same reach, the overbank or fringe area velo-
~ities average betWeen 2.5 to 5 feet per second west of the Beaver
Creek main channel and 2 to 4 feet pcr second cast of Beaver Creek
channel. The average flow depths on the agricultural areas wLthLn
the flood plain on the \lest average botwocn 0.5 and 2 feet.
Special note should be made of the potential hazardous flood
velocities and depths in the downtown and residential area of the
City. Average velocities for the lOa-year flood event were esti-
mated to range between 1 to 3 feet per s~cond; however, localized
velocities on streets and around obstructions may be 2 or 3 times
the average velocity. Velocities in excess of 2 to 4 feet per
second and depths in excess of 2 to 3 feet can be considered as
hazardous to human safety and welfare.

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Other "'loodin'! sou::-ces

Other sources of possible flooding in Brush include the BrUSh
L~teral C~nal and BaJg~r Cree~ overflows. Both of these flood

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sources were inspected and evaluated to ascertain ~n opinion on the
extent and possibility for diverting flood waters into the City of
Brush.
The USGS quadrangle maps show the ground topography east of
Badger Creek to slope towards the City of Brush, approximately 4.5
miles cast. As a result, there is concern for the possibility of
flood waters overtopping the channel b~nks in Badger Creek at the
Burlington Northern railroad and State Highway 6-34 highway crossings and
for the flood waters to travel east to Brush.
Hydrologic calculations indicate the magnitude of the lOO-year
flood on Badger Creek to range between 25,000 cfs and 30,000 cfs.
Hydraulic computations shOW that the backwater effect created by
both the railroad and highway embankments is sufficient to overtop
the channel banks. However, the depth of water overtopping the
channel banks at either location is not sufficient to move the ex-
cess flood waters over the 4.5 miles of CUltivated fields and
irrigation later",ls "nd "mbankments and into Brush. Flooding, how-
ever, can be expected to occur for some distance cast of Badger
Creek along the railroad and high'",ay. Th" worst situation is along
the railroad because of the higher embankment and no provisions for
flows to overtop the embankment.
Flooding has been oxperienced in Brush due to overflows from
the Brush Lateral traversing through the west ~nd north portions
of the City. During tho 1935 flood, much water was diverted from
Bijou Creek into the Upper Platte and Beaver Canal and thence into
the Brush Lat'~ral, only to spill within the City of Brush causing
much damage and consternation. Since that .occurrence, an overflow
spillway has been constructed on the Upper Platte and Beaver Canal
at Badger Creek. This spillway will permit excess flood flows in
the canal to be spilled at a specified and safe location.
Storm runoff may still enter the lateral at many locations
within the City, resulting in possible overflow at other locations.
During period$ of high rainfall and runoff, the City and local

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