Make no mistake, hurricanes Harvey and Irma were natural disasters of unprecedented scale. As these storms loomed and came ashore, the immediate response of governments at every level has been laudable.
The work of first responders and ordinary people helping one another deserves even higher praise. These factors no doubt kept U.S. death tolls as low as they are.
That said, I do not want to get bogged down in the global warming debate; is the phenomenon of global warming real? Will the frequency of hurricane-level storms increase as a result of this phenomenon? Does our reliance on carbon-based energy exacerbate this phenomenon?
There is considerable scientific evidence that the answer to these questions is yes. But politicians, for political and economic reasons, resist this answer. At the same time it is a widely observable fact that ice caps and glaciers are melting, sea levels are rising, and oceans are warming. Shouldn’t that end the debate?
What is not debatable is that hurricanes are occurring more regularly along the southeast and Gulf coasts of the nation; 21 of the 30 most damaging U.S. hurricanes recorded occurred in this region within the last 25 years.
Also not debatable is the fact that the cost of storm-related damage has shot up in recent years. The four most damaging hurricanes in the nation’s history occurred in the last 12 years. Katrina damages came to $108 billion; Sandy’s $75 billion; Harvey damage estimates are between $86-$108 billion; Irma’s, between $64-$92 billion. Damages from the 17 other major storms in the last 25 years averaged $13.5 billion.
It is also true that hurricane damages have little to do with the severity of the storm. Storms are categorized 1-5 (5 being the most severe).
Hurricanes Katrina, Sandy, Harvey, and Irma never exceeded category 3 at landfall and all quickly weakened to a 2 or 1 as they moved inland.
The 17 other major storms in the last 25 years ranged from a tropical storm to a category 5, but the largest majority were in the category 2-3 range.
If storm severity does not dictate hurricane storm damage costs, what then has led to the sharp rise in these costs over the last 10-12 years? In a nutshell, failed federal, state, and local infrastructure maintenance and inadequate land use control programs.
Post-Katrina studies noted that Army Corp of Engineers’ levee maintenance programs had been underfunded for years. As a result levees and floodwalls were overtopped, and some were breached throughout the day of landfall. It was these over-toppings and breaches of the levees that led to the catastrophic flooding of New Orleans and associated damage costs.
Harvey storm damage was significantly increased by similar infrastructure failures; the aging (1940s) Addicks and Barker reservoirs, built west of Houston to contain heavy rains, were overtopped in places and, fearing a breach, controlled releases of water were ordered.
Other storm surge protection projects, the so-called “Ike Dike” and “mid bay” canal at the mouth of (or along) the Galveston ship channel were never funded—clearly a pennywise, pound foolish decision.
At the same time the total absence of appropriate local government land use controls led to overbuilding in vast areas below the dams and proximate to the Buffalo Bayou, such that stormwater run-offs could no longer be absorbed. When floodwaters were released vast areas of residential housing were flooded—the storm damage curve rose sharply.
In sum, Houston, long known for its reluctance to impose building codes, safety codes or zoning ordinances aimed at fashioning safer, more orderly patterns of growth to protect rapidly growing populations and critical oil refineries and chemical production facilities, has reaped what it has sown—heightened hurricane damages.
But Texas and Houston are not alone in their failure to put land use controls in place that steer critical industries, and dense populations away from low-lying flood-prone and storm surge areas.
Overdevelopment of the shoreline is the norm in all of the Gulf states, and along the whole eastern seaboard. Maine and Portland are not immune from these pressures. Federal mapping identifying the most hazardous coastal areas are regularly ignored by developers, and sadly, they are ignored by state and municipal governments charged with protecting the public’s safety.
Greater Miami is the poster-child for this development imprudence; 2.4 million people, 1.3 million homes are less than 4 feet above mean high. Irma storm surges (though not as bad as anticipated) were 6-8 feet in many parts of the state. When does the damage potential become unacceptable?
Orlando Delogu of Portland is emeritus professor of law at the University of Maine School of Law and a longtime public policy consultant to federal, state, and local government agencies and officials. He can be reached at firstname.lastname@example.org.