Seismic hazard mitigation
California is internationally known as ‘earthquake country’ because of its many earthquakes.
The State of California has developed several acts and codes that aim to reduce seismic risks.
The Alquist-Priolo Act for example prohibits development on active seismic fault traces
through land use restrictions (Beatley & Berke 1992, Olshansky 2001). Areas with a high
potential for ground failure can be developed but, according to the Seismic Hazards Mapping
Act, only if the risks of inhabiting a high-risk area are appropriately mitigated (Olshansky
2001). There is a so called unified building code that sets seismic safety standards for all
building constructions. According to the un-reinforced masonry law, communities in high risk
areas have to prepare an overview of all un-reinforced masonry buildings in their community
and establish a mitigation program to reduce these risks. Note that retrofitting is not mandated
(though strongly advised), communities only have to establish a plan for the un-reinforced
masonry buildings and stick to that plan. The exact contents of the plan are up to the local
government (Beatly & Berke 1992).
3.3 Local government
The primary tasks of local governments in natural hazard issues are the initial emergency
response in case of a disaster, an issue that is beyond the scope of this paper, and the
implementation of federal and state mitigation codes and regulations (Palm & Carrol 1998,
FEMA 1997).
Briechle (1999) has thoroughly examined the decision-making process of over 500 local
governments concerning natural hazard mitigation issues. The results of her research are quite
dramatic: only 11% of local governments considers natural hazard mitigation as a priority.
Eighty-three percent of localities had experienced a declared disaster, but only 52% reported
flood as a serious threat, 22% reported earthquakes as a serious threat and 11% reported
hurricanes as a serious threat. A total of 29% of local governments reported the implementation
of mitigation measures, of which development restrictions in high-risk zones are the most
popular measure. Sixty-five percent of local governments experienced concerns about the
financing of mitigation measures, while 34% indicated that funding from state or federal
sources might help to facilitate mitigation measures. State and federal mandates and legal
requirements are the most-heard motivation for adopting mitigation measures (Briechle 1999).
These results indicate once again that strong mandates from higher level governments and
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