FLOOD00275

• County: Adams
• Community: Westminster
• Title: Bruchez Farms Property - Big Dry Creek at Wadsworth Parkway
• Date: 1/1/1998
• Prepared For: Bruchez Farm
• Prepared By: Wright Water Engineers Inc
• Floodplain - Doc Type: Floodplain Report/Masterplan

a. Steo-Backwater Method. Flood water surface profiles
may be calculated by the standard step method employing
the Bernoulli energy equation with energy losses due to
friction evaluated with the Manning equation and other
losses evaluated by shock loss equations.

b. Alternative Methods. An alternative hydraulic
methodology may be accepted by the Board provided it
has been recommended for general use by a governmental
agency or notable scientific body, is well documented
and is available to the general user. In the case of a
computer program, documentation shall include a
published user's manual and a programmer's manual.

4.

Floodolain
boundaries
methods:

floodplain
of the following

Delineation Procedures.
shall be delineated

The
by one

a. Flood Contour Method. A reference line shall be
shown down the center of the low flow channel on the
work maps for all streams studied by detailed methods.
Flood contours, derived from the water surface profile
and corresponding to the map contours, shall be used to
define the boundaries of the 100-year floodplain on the
work maps. The flood contours shall have a vertical
interval equal to the contour interval of the work map
if a) the average slope of the water surface profile
between cross sections is flatter than one to
one-hundred, or b) the width of the floodplain is
greater than 200 feet, or c) there are, in the judgment
of the engineer, unusual topographic features.
Alternate flood contours or index flood contours may be
used in lieu of the above flood contour interval if the
slope of the water surface profile, in combination with
the work map contour interval and scale, would result
in an average horizontal spacing between flood contours
of less than 1 inch. A copy of the work map shall be
provided to the Board for review by the staff prior to
designation and approval under this rule.

b. Mao Contour Method. A reference line shall be shown
down the center of the low flow channel on the base map
for all streams studied by detailed methods. For the
selected channel and floodplain cross sections, the
100-year flood water surface elevations and floodplain

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