FLOOD10655 ‎(2)‎

• County: Chaffee
• Community: Salida
• Title: FIS - Salida
• Date: 9/30/1982
• Prepared For: Salida
• Prepared By: FEMA
• Floodplain - Doc Type: Current FEMA Regulatory Floodplain Information

Flood profiles were drawn showing computed water-surface elevations
to an accuracy of 0 e 5 foot for floads of the sel ected recurrence
intervals" The flood profiles presented in this study are based on
the effects of flow through unobstructed hydraul ic structures and
area, thus, considered valid only if these structures do not fail and
remain unobstructed. Hydraulic analyses were conducted by ewes
(Reference 1) and reviewed by the study contractor. Starting water
surface elevations were determined by the slope-area method.

Horizontal control is based on Colorado State Plane Coordinate System
South Zone 1929 use & GS Sea Level Datum. Elevation reference marks
used in this study are shown on the maps.

The Flood Hazard Boundary Map (FHBM) for the Arkansas River in
Salida (Reference 7), was reviewed during the hydraulic analysis of
this study. The FHBM was prepared using 7 1/2 minute USGS quadrangle
maps for contourinfonnati on. Channel cross-sections were field
surveyed by the City of Salida, at several locations along this reach
of the Arkansas River. These cross-sections were used to determine a
nonnal depth at each section, and a new Zone A boundary was then
delineated as shown on the Flood Insurance Rate map (published separ-
ately), for the City of Salida.

4.0 FLOOD PLAIN MANAGEMENT APPLICATIONS

The National Flood Insurance Program encourages state and local governments
to adopt sound flood p 1 a i n lnanagement programs. Therefore, each Flood
Insurance Study incl udes a fl ood boundary map designed to assi st commun-
ities in developing sound flood plain management measures.

4.1 Flood Boundaries

In order .to provide a national standard without regional discrimi-
nation, the lOO-year flood has been adopted by FEMA as the base flood
for purposes of flood plain management measures. The SOD-year flood
is employed to indicate additional areas of flood risk in the com-
munity. For each stream studied in detail, the boundaries for the
100- and 50D-year floods have been delineated using the flood eleva-
tions determined at each cross section; between cross sections,
the boundaries were interpolated using topographic maps at scale of
1:4800, with a contour interval of 2 feet (Reference 6). In cases
where the lOO-and 50D-year flood boundaries are close together, only
the lOO-year flood boundary has been shown.

Flood boundar; es for the 100- and 50D-year floods are shown on the
Flood Boundary and Floodway Map. Small areas wi thi n the fl ood
boundaries may lie above the flood elevations and, therefore, may
not be subject to flooding. Owing to limitations of the map scale,
such areas are not shown.

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