Environmental Engineering Reference
In-Depth Information
only be determined for, a given location. Two examples of coastal impacts
are discussed here: New York City and the Sacramento-San Joaquin Delta
of California.
New York City (NYC) is both a mega-delta and a mega-city located along
the eastern seaboard of the United States. Return times of current 100-year
and 50-year coastal storms for NYC are strongly correlated with global and
local sea level rise (Figure 5.10, based on Kirshen et al., 2008a). Based on
historical records, the projected frequency of coastal storms can be trans-
lated into an estimate of the number of buildings in downtown NYC that
would be damaged by storms characterized by their current FEMA-based
return times (Figure 5.11, based on NYCOEM, 2009).
New York City has responded to these risks by considering a range of
adaptation options to reduce the vulnerability of its critical public and pri-
vate infrastructure over time (NPCC, 2009). One option envisions creating a
dynamic process by which FEMA systematically redraws its 100-year flood
maps as sea level rises, so insurance markets could appropriately spread the
risk. Other plans envision constructing retractable barricades to protect New
York from an impending storm—much like the barrage on the Thames that
protects London (where plans are underway to build a new barrier based on
observed and estimated sea level rise); the barrier that protects St. Petersburg,
Russia; and multiple devices now being installed to protect Venice at the
border of its lagoon and the Adriatic Sea. The city is considering adjust-
FIGURE 5.10 Projected return time of coastal storms relative to future sea level rise for
New York City (Based on Kirshen et al., 2008a).
