FLOOD02335

• Designation Number: 258
• County: Pueblo
• Community: Pueblo
• Basin: Arkansas
• Title: Flood Insurance Study - Pueblo
• Date: 9/1/1986
• Designation Date: 9/1/1986
• Floodplain - Doc Type: Floodplain Report/Masterplan

4.0 FLOOD PLAIN MANAGEMENT APPLICATIONS

The National Flood Insurance Program (NFIP) encourages State and local
governments to adopt sound flood plain management programs. Therefore,
each Flood Insurance Study produces maps designed to assist communities
in developing flood plain management measures.

4.1 Flood Boundaries

To provide a national standard without regional discrimination,
the 1 percent annual chance (100-year) flood has been adopted by
FEMA as the base flood for flood plain management purposes. The
0.2 percent annual chance (SOO-year) flood is employed to indicate
additional areas of flood risk in the community. For each stream
studied in detail, the 100- and SOO-year flood plain boundaries
have been delineated using the flood elevations determined at each
cross section. Between cross sections, the boundaries were inter-
polated using the following sources:

For the Arkansas River, Fountain Creek, Wild Horse-Dry Creek, and
the Bonforte Boulevard Area, flood plain boundaries were delineated
on topographic maps at a scale of 1:24,000, with a contour interval
of 10 feet (Reference 21). These maps were supplemented by topo-
graphic maps for Fountain Creek at a scale of 1:1,200, with a contour
interval of 2 feet (Reference 17). Detailed flood plain boundaries
for University park Tributary were delineated on a topographic map
at a scale of 1:2,400, with a contour interval of 2 feet (Refer-
ence 18).

The 100- and SOO-year flood plain boundaries are shown on the Flood
Boundary and Floodway Map (Exhibit 2). In cases where the 100-
and SOO-year flood plain boundaries are close together, only the
100-year flood plain boundary has been shown. small areas within
the flood plain boundaries may lie above the flood elevations but
cannot be shown due to limitations of the map scale and/or lack of
detailed topographic data.

The 100-year flood plain boundaries for the west bank overflow
from Fountain Creek through downtown Pueblo were delineated on a
planimetric map at a scale of 1:1,200 (Reference 22), based on the
results of the hydraulic analyses discussed in Section 3.2. This
map was used for the overflow from Fountain Creek at Santa Fe Avenue
south to Elizabeth Street. Between Elizabeth Street and the Arkansas
River floodwall, flood plain boundaries were delineated at a scale
of 1:24,000 on the topographic map discussed previously (Refer-
ence 21). These boundaries were taken from a report prepared by
the study contractor for the City of Pueblo (Reference 2). The
SOO-year boundaries were adopted from the previous COE study
(Reference 1).

The SOO-year flooding leaves Wild Horse-Dry Creek and flows east
along the railroad yard north of the Arkansas River and joins shal-
low flooding from the west bank overflow of Fountain Creek. The

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