FLOOD06039

• Designation Number: 124
• County: Boulder
• Community: Unincorporated Boulder County
• Stream Name: Dry Creek
• Basin: South Platte
• Title: Floodplain Information Report - Dry Creek, Boulder County-Weld County, CO
• Date: 6/1/1978
• Designation Date: 11/1/1978
• Floodplain - Doc Type: Floodplain Report/Masterplan

respect[vely. The flood may occur In any year.
stat[stlcal analyses of streamflow records and
fall and runoff characterlst[cs In the general
watershed.

It Is based on
analyses of raln-
region of the

Sheet Flow
The water. which Is diverted from the.ma[n floodflow by
obstructions and variances In topography. This water flows at
shallow depths and normally at elevations different from the water
flowing In the adjacent channel or on the adjacent flood pla[n.
Due to the shallow depths and Irregular flow patterns associated
with this type of flow, computations to predict flow depth are
considered Impractical.

,

Standard Project Flood <S.P.F.)
The flood that may be expected from the mqst severe com-
b[natlon of meteorolog[cal and hydrological conditions that are
considered reasonably characteristic of the geographical area In
which the drainage basin [s located, excluding extremely rare com-
binations. Peak discharges for these floods are generally about
40 percent to 60 percent of the Probable Maximum Floods for the
same basins. Such floods, as used by the Corps of Engineers, are
Intended as practicable expressions of the degree of protection
that should be sought In the design of flood control works, the
failure of which might be disastrous.

Top of Waterway
This Is the roof of the opening [n a stream crossing
through which water flows under normal conditions. It Is the
underside of the deck span - sometimes called "low steel", the
roof of a box culvert, or the crown of an arched or circular
culvert.

28

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