Coastal Construction Manual - National Ready Mixed Concrete ...

IDENTIFYING HAZARDS 3
Figure 3‐18.
Intact houses floated off
their foundations and
carried inland during
Hurricane Hugo in 1989
(Garden City, SC)
Figure 3‐19.
Storm surge at Horseshoe
Beach, FL, during Tropical
Storm Alberto in 2006
SOURCE: NOAA NATIONAL
WEATHER SERVICE
FORECAST OFFICE
Tsunamis
Outflow (flow in the seaward direction) of floodwaters
driven into bay or upland areas
Strong currents parallel to the shoreline, driven by the
obliquely incident storm waves
High-velocity flows can be created or exacerbated by the
presence of manmade or natural obstructions along the
shoreline and by weak points formed by shore-normal roads
and access paths that cross dunes, bridges or shore-normal
canals, channels, or drainage features. For example, evidence
NOTE
Storm surge does not correlate
to hurricane category according
to the earlier Saffir-Simpson
Hurricane Scale, so the scale
was renamed (Saffir Simpson
Hurricane Wind Scale) and
changed in 2010 to eliminate any
reference to storm surge (see
Table 3-1).
after Hurricane Opal struck Navarre Beach, FL, in 1995 suggests that large engineered buildings channeled
flow between them (see Figure 3-20). The channelized flow caused deep scour channels across the island,
undermining a pile-supported house between the large buildings (see Figure 3-21), and washing out roads
and houses (see Figure 3-22) situated farther landward.
COASTAL CONSTRUCTION MANUAL
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