  The mobility of residents and their access to essential services can be
highly affected by transportation network closures that occur during and after
coastal hazard events. Few studies have used geographic information systems
coupled with infrastructure vulnerability models to explore how spatial
accessibility to goods and services shifts after a hurricane. Models that
explore spatial accessibility to health services are particularly lacking. This
study provides a framework to examine how the disruption of transportation
networks during and after a hurricane can impact a residents ability to access
health services over time. Two different bridge closure conditions, inundation
and structural failure, along with roadway inundation are used to quantify
post-hurricane accessibility at short- and long-term temporal scales.
Inundation may close a bridge for hours or days, but a structural failure may
close a route for weeks or months. Both forms of closure are incorporated using
probabilistic vulnerability models coupled with GIS-based models to assess
spatial accessibility in the aftermath of a coastal hazard. Harris County, an
area in Southeastern Texas prone to coastal hazards, is used as a case study.
The results indicate changes in the accessibility scores of specific areas
depending on the temporal scale of interest and intensity of the hazard
scenario. Sociodemographic indicators are also examined for the study region,
revealing the populations most likely to suffer from lack of accessibility.
Overall, the presented framework helps to understand how both short-term
functionality loss and long-term damage affect access to critical services such
as health care after a hazard. This information, in turn, can shape decisions
about future mitigation and planning efforts, while the presented framework can
be expanded to other hazard-prone areas.
