Resilient Cities: Coping With Natural Hazards - Theme Cities: Solutions for Urban Problems - page 326

9.7.2 Initial Knowledge of Risks and Vulnerabilities

9﻽7﻽2﻽1 Hazard Mechanisms

The first s tage in any approach to risk reduction is to assess what types of natural
hazards are likely to affect any community or urban place, especially by review-
ing historical records of previous natural events in the area, and also to understand
the mechanisms involved. In our scientific era increasing research efforts have im-
proved our understanding of the way that these processes develop, move and decay,
not simply empirically, but also by modelling techniques (Zebrowski 1997 ; Blaikie
et al. 2004 ; Abbott and Sampson 2009 ; Smith and Petley 2009 ; Diacu 2009 ). Al-
though we do not have the ability to predict the next incidence of many of these po-
tential hazards, the general area of risk is usually known, and the path and speed of
their development—especially in climate-related events—can now be predicted and
publicised through various forecasting systems that involve national environmental
research agencies, and international co-operation. This specialist research on hazard
development and incidence is often beyond the capacity of individual urban places
to produce such work, although some carry out monitoring functions. Usually the
information from these specialist hazard agencies is forwarded to local and national
governments, although there are still too many examples where the warning is de-
layed, reducing the time for emergency measures to be implemented.

9﻽7﻽2﻽2 Vulnerability of Structures to Hazards

Greater understanding of the mechanisms of various natural hazards needs to be
complemented by detailed knowledge of the vulnerability of the physical struc-
tures, transport systems, utilities and food supplies. This involves an assessment of
the extent to which the physical infrastructures and buildings will be able to with-
stand extreme natural events by reviewing the strength and flexibility of buildings
and infrastructure to withstand any extreme event, such as earthquakes, storms or
floods. Although expert advice is often needed to assist in the process it should be
the responsibility of local government to have people capable of undertaking these
assessment exercises, which not only assess the city's buildings and infrastructures
but also those of private companies. For example, the severe storm codenamed
Sandy in October 2012 that affected 15 American states over an area as big as
Western Europe, only led to 120 deaths, a small number when one considers it left
damages of $ 30-50 billion. It was particularly devastating because of the flooding
it produced in and around New York and New Jersey; in the latter state almost a
quarter of a million people live less than five feet above high water level. Although
the main electric utility company that services New York City and nearby counties
designed its facilities to withstand a sea-surge of 3.8 m, the storm created sea surges
of over 4.3 m in some areas, illustrating that the risk level for key facility locations
had been under-estimated, even in an affluent city at the heart of the world economy.