Interconnecting Networks of Social Vulnerability, Resource Access, and
High-Resolution Inundation to Quantify Household Flood Impact
Abstract
The frequency of major flooding events continues to increase, fueling
the already growing concern in numerous fields about quantifying the
inequitable distribution of flood hazards. Our previous work of
overlaying high resolution flood exposure data with social vulnerability
information has already begun to highlight how different communities
experience varying levels of risk. However, this fails to capture the
complex nature by which flooding affects interconnected infrastructure
and service networks which further have an impact on an individual and
community’s risk. Our goal is to quantitatively define an individual’s
vulnerability to flooding, encompassing how both pluvial and fluvial
inundation impacts an individual’s place of residence and disrupts their
access to critical resources, including flood, gas, healthcare, and
emergency services, while still considering an individual’s
socioeconomic standing. With the goal of estimating household level
disruption of access to critical resources in near real time, our
approach relies on a multilayer network of social vulnerability,
transportation infrastructure, essential resources, and emergency
services. To estimate inundation in near real time, we utilize the Heigh
Above Nearest Drainage (HAND) method and a topographic depression
hierarchy algorithm to estimate fluvial and pluvial flooding. Using a
minimum cost flow algorithm, we determine an individual’s relative cost
to access resources before, during, and after a major flooding event.
Combining technical and social information leads to the identification
of communities that are more vulnerable to the physical, economical, and
social components of floods. This model will be useful in future
descriptive and prescriptive analytical frameworks by identifying
critical nodes across networks and providing actionable knowledge on at
risk communities. Our model will inform agencies involved in flood
management, urban planning, and emergency response on where they can
best apply resources to increase the resiliency of communities and the
infrastructure they rely on.