Introduction
Dams are defined as an artificial obstruction to natural flows, which
helps to accumulate water for agricultural reasons and energy
generation, potable water supply, flood mitigation, and also
recreational reasons (ICOLD, 2008). On the other hand, dams are
mentioned as one of the key assets in the Critical Infrastructures and
Key Resources (CIKRs) by the Department of Homeland Security (DHS) in
the United States. There was a huge initiative from the federal
government to coordinate a set of resilience and protection plans
series, started the process of understanding what features create
resilience in CIKRs (Gopalakrishnan & Peeta, 2010). Due to this
mission, dams and their environment should be designed for a safer, more
secure, and more resilient domination by preventing, deterring,
neutralizing, or mitigating the effects of deliberate efforts by
terrorists to destroy, incapacitates, or exploits their elements (Fisher
et al., 2010). There are also other programs for the protection of
critical infrastructures such as the Swiss Federal program for critical
infrastructure protection (CIP) to analyze its threats and identify
vulnerabilities and assessing risks.
In principle, to assess the risk and provide the protection plan for
dams and their downstream areas all relevant hazards and threats must be
considered. The risks or vulnerabilities related to dams often refer to
natural hazards such as earthquakes or floods or other technological
failures. On the other hand, the spectrum of hazards and threats can be
of many-sided nature, either technology- or human-related, natural and
operational as well as contextual, which should be considered while the
vulnerability of infrastructures should be assessed. Most of the
researches in the last decades focuses on the natural hazards threats
spectrum. However, the emergence of terrorist groups such as Al-Qaeda
and ISIS revived the idea of protection of human-related threats. The
spectrum of human-related threats ranges from unintended errors to
targeted malicious attacks, either physical (e.g., explosive devices) or
cyber, which deal with sophisticated models capable of describing
thought and ideology transposed to terror and destruction (Kröger &
Zio, 2011). Thus, risk assessment and vulnerability assessment should
expand to all properties related to the dams from farms, transportation
routes, energy lines, pipes, business areas, industries, cities or
villages, and even biosphere assets. There are much research works on
the loss of life and flood mortality highlighted by different models and
frameworks especially developed by Jonkman and his teams (S. Jonkman &
Vrijling, 2008; S. Jonkman, Vrijling, & Vrouwenvelder, 2008; S. B.
Jonkman, Maaskant, Kolen, & Needham, 2016; S. N. Jonkman, Maaskant,
Boyd, & Levitan, 2009). He divided different methods in loss estimation
into three categories as macro-level by characterizing the event,
Meso-level by characterizing the location, and finally micro-level by
investigating the individuals (S. B. Jonkman et al., 2016). In the
developed equation, the important property is people, and any risk
number is calculated based on the number of people at risk and two
reducing factors as sheltering fraction (Roozbahani, Zahraie, & Tabesh)
and evacuation fraction (FE) which is illustrated in
eq.1. The mortality fraction is the other factor (Fd)
that has been used in other risk assessment equations (eq.2) where N is
a number of people at risk and NPAR is the number of
people at risk.