Assessing the Hazard from Aging dams in the U.S.A.
Abstract
Climate change, inadequate maintenance, and aging beyond the design life
increase the probability of dam failure. Dam failures can have
significant social, financial, and environmental impacts. Financial
losses can extend beyond infrastructure replacement costs, with
cascading effects in multiple sectors such as electricity,
transportation, water supply, and environmental services. The existing
dam hazard classifications in the United States do not formally
characterize “hazard hotspots” considering these impacts. Given that
there are over 90,000 dams with different states of disrepair,
maintenance, and budgetary constraints, a better way to rank their
potential hazard and allocate resources for risk mitigation is needed.
We present an approach that is scalable over many regions for rapidly
assessing the magnitude and exposure of a dam failure for a preliminary
ranking of the priority areas of concern. The estimation of the
consequences of a dam failure including financial losses, affected
critical infrastructure, and population is addressed using publicly
available dam break and consequence tools and national infrastructure
datasets. Dams can be ranked using seven criteria following the
Analytical Hierarchical Process. The application of the framework is
demonstrated with dams in the Cumberland River Basin. The main barrier
to applying this approach at a national scale is the estimation of the
inundation area upon dam failure, and we outline a strategy to implement
it. The importance of increasing the resilience of dams is becoming more
critical given the increasing interest in hydropower as a renewable
energy source in the face of climate change.