Board Meeting 10/01/1987

• Board Meeting Date: 10/1/1987
• Description: CWCB Meeting
• Board Meetings - Doc Type: Meeting

.

floods. Photographs shall be taken of the
study reaches of the stream channel and
floodplain to support roughness coefficients
used for hydraulic computations. The methods
described in "Determination of Roughness
Coefficients for Streams in Colorado," U.S.
Geological Survey, 1985, are acceptable to the
Board.

.

7. Consistency. A comparison of any proposed
100-year flood profile with all previously
designated and approved information shall be
provided to the Board. Except where a clearly
identified change in flooding characteristics
or error in the existing data can be shown,
the proposed 100-year flood elevations shall
agree with those of other contiguous studies
on the same stream. Elevations of cross
sections shall be computed to match within
iO.5 foot of an existing valid elevation;
however, the final published lOO-year flood
water surface profile shall be shown to match
the contiguous study exactly. Where
elevations cannot be reconciled to within iO.S
foot because of changed flooding conditions or
an error in the previous analysis, a full
explanation and justification for the
difference shall be provided to the Board.

D. Published Report and Map

1.

Re>>orts. All
information which
for designation
entitled, dated,
document.

detailed
is presented to
and approval
and bound in an

floodplain
the Board
shall be
individual

2 .

Published Ma>> Scale.
area map scale shall
feet or such map scale
The Board recommends a
1 inch equals 400 feet.

The published flooded
be 1 inch equals 1000
Showing greater detail.
published map scale of

3. Discre>>ancies. Where discrepancies appear
between flooded area maps and water surface
profiles, any 100-year water surface profile
designated by the Board shall take precedence
over any corresponding flooded area map for
the same stream reach.

.

-17-