Dams (and their collapses) are one of those risks which are latent and underappreciated but devastating force-multipliers of weather and climate-related events.
The Derna dam collapses, even with only partial death reports is already the second deadliest recorded dam failure, and is close on the lower-end range of death estimates for the worst, the 1975 Banqiao Dam failure in China, following another weather catastrophe, Typhoon Nina.
(If memory serves, Nina both stalled out over the Banqiao region and intersected with a more northerly cold front, creating a deluge effect similar to that of Superstorm Sandy over New York and New England, where warm tropical moisture was wrung from the atmosphere as it intersected colder air. In Nina's case, over a meter of rain fell within 24 hours.)
Dams are deceptively complex structures which appear simple, and can be built with relatively simple technology and persist for long periods of time with little ongoing maintenance and administration ... until they cannot. Most especially, dams are especially prone to governmental dysfunction in oversight, regulation, maintenance, and emergency planning. That last should include planning, risk assessment, risk mitigating, public education about risks and procedures, warning systems, crisis communications (between dam operators and government, and dam operators and downstream communities), disaster drills, and training in rescue, recovery, and relief operations.
Libya, a failing state divided by conflict, and for over forty years an autocratic dictatorship under a single ruler, lacks autonomous, independent, capable, and effective institutions for operating such infrastructure. It's all but certainly not the only such region.
Even what are considered to be rich and well-functioning democratic states see dam failures, or near failures. The near-failure of the Oroville Dam in California in 2017 followed mismanagement by the state water authority. The actual failures of the Edensville and Sanford Dams in Michigan in 2020 followed years of mismanagement by a private owner and ineffective regulation by the Michigan Deparment of Environment, Great Lakes, and Energy. In that case, property was damaged but no lives lost. Lake Dunlap in Texas suffered a spillway failure in 2019, again with ineffective management and regulation by this time by the Guadalupe-Blanco River Authority, though again without loss of life.
One of the highest-risk dams in the United States is Isabella Dam, on the Kern River upstream of Bakersfield, CA. The topography somewhat resembles the images I've seen of Derna: a mountainous upstream terrain, narrow canyon, and a city lying directly in the floodplain of both the river and any potential dam collapse.
The problem presented by such dams with ongoing climate change is that all the factors involved compound:
- Climate change increases risks of extreme weather events, including Mediterranean-basin cyclonic storms as with Daniel.
- Climate-related stresses, including reduced crops and increased food prices, stress already-straining marginal states. The Arab Spring protests which ended up toppling Qaddafi's Libyan regime have been blamed in part on food stress from reduced harvests and increased food prices.
- Governmental corruption and ineffectiveness raise all potential disaster threats. What would be a modest property-related disaster with preparation, warning, evacuation, and response becomes a mass fatality event where one or more element is missing.
- Decreased liberal freedoms also tend to restrain technical concerns and criticisms. This was certainly the case at Banqiao, seems to be the case in Derna, and can be seen in other recent catastrophes such as the 2020 Beirut ammonium nitrate explosion (which also exhibited several other factors mentioned here).
A core problem with disaster and risk planning is that often contributing factors which are treated as independent turn out to be strongly correlated and interrelated. I believe we're seeing that again here.