Floods and Other Disasters: Knowing More, Yet Losing More

Despite more knowledge and ability to manipulate nature, we have increased our exposure and susceptibility to natural hazards. Why? Distinguished Carolina Professor Susan L. Cutter explores our current hazardscape

[Historical natural disasters reveal that the severity of the human toll could be lessened—if society and technologists would take heed. But despite the fact that the Federal government handles flood insurance, there is no Federal national database collating data from past disasters that could inform current policies! So pointed out Distinguished Carolina Professor and geographer Dr. Susan L. Cutter from the University of South Carolina in the 2014 Gilbert F. White Lecture in the Geographical Sciences given at the National Academy of Sciences on December 4. Using field research from Hurricanes Katrina (2005) and Sandy (2012), Cutter examined societal factors making people and places vulnerable to hazards, why hazards vary with location, and what must change if people and property are to be genuinely protected. 

Relevance to the unusually powerful Great Easter 1913 winter storm system and flood? A century later, that natural disaster—which killed some 1,000 people and wreaked more property damage than Hurricane Katrina centered on the industrial north—is still the flood of record in Indiana and Ohio as well as in parts of a dozen other states. Climate models predict more intense rainfall in the Midwest in the coming decades, including the effects of Gulf and Atlantic hurricanes penetrating further inland. Indeed, 70+mph winds from Hurricane Sandy in 2012 caused so much damage in Ohio that Ohio itself was made eligible for Federal disaster relief. If climate models prove accurate, intense concentrated rainfall of the scale of the mammoth 1913 storm system and flood today—whether from hurricane or from winter storm system—would be devastating to key national infrastructure. Below, with Cutter's permission, is a summary of her talk “In Harm’s Way: Why More Knowledge is Not Reducing Losses" along with some of her slides.]

We are on a “disaster loss up escalator” in the United States, declared Susan L. Cutter, Distinguished Carolina Professor at University of South Carolina. Despite the fact that we know more today about hazards than we did half a century ago, the statistics are clear: annual U.S. losses to natural disasters have nearly tripled—from under $25 per capita (2009 dollars) in the 1960s to more than $70 per capita in the 2010s (2009 dollars), despite the fact that population itself has doubled.

Why is that? Some explanations are clear: because of greater population density and greater personal/business wealth, smaller-magnitude weather events can produce bigger losses. But it is also clear that intense weather events are increasing in frequency, and that people are building in more high-hazard areas (in part because often they have desirable views, say, of coastline beaches). But the real explanation goes deeper. “In many ways, we have a failure to act to help reduce loss,” Cutter said.

Cutter suggests three causes of the hazard loss paradox:  lack of loss accounting, lack of understanding science, and lack of the use of science in public policy and practice. 

No national database of disaster losses

“We don’t have a national database of hazard event and losses in the United States!” Cutter pointed out, ticking off her first major point about causes for the hazard loss paradox. “The National Oceanic and Atmospheric Administration (NOAA) has a database, but it is only weather. The U.S. Geological Survey (USGS) has some data, but it’s inconsistent. Every Federal agency has some data, but it’s not in one place, and [no single database covers] all hazards.”

The absence of a comprehensive Federal national database of natural disaster losses is not a new concern. In 1999, Cutter recounted, the National Academy of Sciences produced two separate studies followed by a third in 2001, all calling for disaster loss accounting and pointing up the need for such a national database. Fourteen years later, the situation has not changed. That being said, she noted, no other nation has a national database, either.

These three National Academy of Sciences reports from 1999 and 2001
all called for a Federal national database on natural disaster losses.

That begs a key question: “How can you reduce losses when you don’t know where the hazards are, or when, where, and how much?” Cutter asked. “How do you begin to tackle the problem of reduction when you don’t know the baseline?”

A private database does exist at the University of South Carolina. Called the Spatial Hazard Events and Losses Database for the United States (SHELDUS), it has more than 800,000 records from 1960 through 2013, geocoded to the county level across the nation, drawing on information from NOAA, USGS, the Department of Agriculture, and other sources of loss information. Until mid-2014, it was searchable online free of charge. Because no Federal support exists to maintain SHELDUS, however, “we had no option but to change to a fee basis,” Cutter said.

Second, she pointed out, hazard science knows some things well. “We know that mitigation works: for example, putting hurricane straps between the rafters and the roof makes a difference in a high wind environment,” Cutter said. “We also know that mitigation pays: every dollar in mitigation spent saves four dollars in losses.” Much is known about monitoring, about the physical basis for extreme events, and about how many people live in high-hazard areas. Forecasts are getting ever better for the timing of hurricanes and impact areas.  

SHELDUS, the only database for U.S. hazard losses, is
not Federally supported.

Other aspects of hazard science are known less well. Key among them are how, when, and where to anticipate complex events or cascading events. “What is the surprise in the system that we don’t know and can’t imagine?” Cutter asked. “We know that there are incredible interdependencies between infrastructure systems, human systems, and natural systems, but we are not sure about the connectivity among them in all places for all things.” 

Also less well known is the effectiveness of existing policies and practices in hazards management, “in large part because we have not done a review or audit of these policies and programs to see if they actually are reducing loss,” she said. Vulnerability is an important component of disaster risk, “but we don’t know how to measure it” nor how to quantify how historic or antecedent social conditions that either increase or decrease vulnerabilities and exposure. 

One thing is clear, however, she emphasized: “Multidisciplinary and interdisciplinary perspectives are key in hazard science.”

Social vulnerability index

A geographer’s view of vulnerability and resilience differs from an engineer’s or a hydrologist’s because the focus is on “how vulnerability and resilience varies among social groups and varies geographically,” Cutter said. The goal of such studies “is to make a difference: to take the science and to put it into practice.” Over the past two decades, she and her colleagues have focused on ways to objectively measure social vulnerability, resilience, and recovery.

For measuring vulnerability, they devised a social vulnerability index (SoVI, pronounced SOE-VEE): “the identification of quantifiable attributes of populations that make them more or less susceptible to harm, and mapping them to look at geographic distribution,” she explained. 

Interpreting the map, however, requires a deeper, detailed understanding of the social geography across the country. For example, Cutter noted, in the Mississippi Valley, “vulnerability is related to female head of households, poverty populations, and African Americans. That’s very different from what you see in Arizona, where vulnerability is related to Native American reservations. Both are different from what you see in eastern Kentucky, where vulnerability is related to white, less educated, poverty populations. One of my favorite examples [of the need for detailed local knowledge] is Nebraska and parts of North and South Dakota,” she continued. “Although social vulnerability in parts of South Dakota is related to Native American lands, in other areas of the Great Plains vulnerability is related to in situ aging of the female population on the family farm, living on a fixed income with very little resource base or flexibility should that disaster hit. In many instances, the husband has died; the widow has stayed on the farm but the children have moved to the cities to seek employment, so resources are highly constrained.”

“We’ve done a lot of testing,” Cutter continued. The social vulnerability index “works in counties, in census tracts, and across different nations.” It is now gaining traction in policy circles as a way of planning how one might distribute or position resources for aid, response, and recovery. “During Hurricane Sandy, we got a call from the regional office of FEMA, asking us to do a run on SoVI for the three-state area because they wanted to see where they might need to deploy resources and target efforts,” she recounted. The index “gives governments a way of prioritizing that they would not have had before.”

Quantifying resilience

Cutter quoted the National Academy of Sciences definition of resilience as “the ability to prepare and plan for, absorb, recover from or more successfully adapt to actual or potential adverse events.” The concept of resilience has gained

keen interest not only in the U.S. Federal government but also in the United Kingdom and the United Nations. Meantime, the Rockefeller Foundation has embarked on a major effort to help cities develop disaster resilience and the National Academies has developed a Resilient America Roundtable to help communities develop a culture of resilience. 

“Everyone is talking about resilience as a way of moving from a focus on disaster risk reduction to a broader framing in sustainability,” Cutter observed. “The question is: how do we know if these efforts will be successful? We don’t have metrics: We don’t know how to measure resilience, and we don’t have a baseline. If we don’t have a baseline to know how resilient we are now in the absence of these policy innovations, how are we going to know whether or not they are effective?” Moreover, in the literature, Cutter said, the issue becomes resilience of what? and resilience for whom? Thus, attempts at developing metrics for resilience have been inconsistent with one another. “You can look at social resilience, or institutional resilience, or community capital. But across the nation, each of these different types of resilience has a very different geography.”

Measuring recovery

“Recovery is a natural laboratory, where we can actually see how vulnerability and resilience influence the capacity of communities to respond after an event,” Cutter noted. And research questions abound: Does the social transformation of the landscape follow its same trajectory after a disaster as beforehand? Is recovery spatially or temporally uniform? Or are there persistent inequalities in the recovery process? Answering such questions requires some objective way of measuring recovery.

“Well, being geographers and liking to go out into the field after disasters, we’ve developed a number of ways to do this,” Cutter recounted. One “crude but useful” technique was repeat photography: returning to the same locations every six months to photograph the same homes and other structures to document their stage of recovery. The photographs could be categorized using such objective evidence as debris removal, demolition, or rebuilding, and a property coarsely scored as showing no recovery, 25%, 50%, 75%, or full

recovery. Then, “because we [geographers] are very good at all things spatial, you can then take those points and create a surface [map] representing both the spatial and the temporal change,” Cutter said. After Hurricane Katrina in 2005, because so many people were rushing to New Orleans, the team decided to focus on residences on the largely overlooked coast of Mississippi. They have now photographically documented recovery at six month intervals along the 130-mile Mississippi coast for nine years.

But recovery in a region is influenced also by “the historical conditions that allow that place to become what it is today,” Cutter said. “The environmental and social history of coastal Mississippi has been shaped not only by hurricanes, but also the historical legacy of social and economic development and segregation.” 

For example, during Hurricane Camille in 1969, there were two separate evacuations, one for whites, the other for blacks. They went to different places. There were inequalities in food aid: Families who had the same number of children who were white got more money from the Federal government than families who were African American. The same thing happened with Small Business Administration loans: 90 percent of them went to white small businesses, not black small businesses. After Camille, Federal disaster money was used for a social good. “Camille struck during the Nixon Administration, and Mississippi refused to integrate its schools,” Cutter recounted. “The Federal government, at the urging of Leon Panetta [then Director of the Office for Civil Rights, a sub-agency of the U.S. Department of Education], said we are not giving Federal aid money to Mississippi until you integrate the schools. The governor of Mississippi said no. Federal disaster aid was withheld and Mississippi given until December 31, 1969, to integrate the schools. And they did.” 

The patchwork quilt of recovery
is discussed in this 2014 book

That segregation legacy still resonates in coastal Mississippi. “In many ways, Hurricane Katrina was a replication of what happened in Camille 35 years earlier,” Cutter observed. “It was not as segregated a society in 2005 as it was in 1969, but the vestiges of residential segregation were still there in terms of housing location and the quality of the construction for minority residents.” 

The scale at which recovery is viewed also matters, Cutter noted. At the county level along the Mississippi coast, the general pattern of recovery looks fairly good, but examination at the neighborhood level reveals a veritable patchwork quilt of recovery. As late as 2010, there were still areas in demolition mode. “That is an indication that the scale really matters: that there are some communities and neighborhoods that are simply not recovering, despite the fact that the general pattern looks fairly good,” she observed. Remote sensing imagery also records geographical shifts in development. And changes in demographics reveal that both young families and retirees were leaving the area.

In short, different types of measurements document that “today’s coastal Mississippi has a smaller spatial footprint, a smaller population, fewer retirees,” Cutter summarized. “The majority is still white, but diversity is increasing, largely through an influx of Hispanic populations. There is increasing social vulnerability. We project that it will take about 19 years for the population of communities to return to what they were before Hurricane Katrina.” 

A tale of two regions

Cutter’s second case study was Hurricane Sandy, which hit New York City and the coast of New Jersey in 2012. “Just as we focused on Mississippi because everyone was going to New Orleans, and we focused on New Jersey because everyone was going to New York City,” Cutter said, showing a slide that depicted the social vulnerability map underlying the storm track. As with the Mississippi coast, field teams began documenting the rebuilding of structures immediately after Sandy and at six-month intervals thereafter.

The contrast couldn’t have been greater. “In Mississippi six months after Katrina, zero of those points had fully recovered. But in New Jersey six months after Sandy, nearly 75% of those structures that we visited had recovered,” Cutter said.

In comparing the two case studies, Cutter pointed out factors that made the two recoveries so different. In Mississippi, there was slowness in Federal investment in infrastructure, and the governor made a decision to use the initial recovery money for business development, specifically the Port of Gulfport—meaning that low- to middle-income housing was not constructed, and former residents had to go somewhere else to live. “One of the biggest issues retarding redevelopment was the availability and affordability of flood insurance” from the National Flood Insurance Program, Cutter continued. Because the base flood elevation [the flood height having a 1% chance of being reached or exceeded in any given year] along coastal Mississippi is so high, coverage would require the homes to be elevated 8 to 9 feet above base elevation, plus 1 or 2 feet of freeboard [safety margin] on top of that. “So you’re talking about massive structures,” Cutter noted. In later years, recovery along the Mississippi Coast was further retarded by multiple shocks having nothing to do with Hurricane Katrina. During the mortgage crisis of 2007–2008, people could not get mortgage financing to rebuild their homes. The Deepwater Horizon Gulf oil spill in 2010 fouled the white beaches and hit both the tourism and fishing sectors of the local economies. And in 2012, the area was struck by another hurricane, Hurricane Isaac. 

In contrast, Cutter noted, a third of the housing stock along the Jersey shore is vacation homes. After Hurricane Sandy, those homeowners “were not flooded from their primary residences, so they already had a house they could live in while rebuilding,” Cutter said. Despite FEMA efforts, there was very little penetration of flood insurance: fewer than half of New Jersey communities carried flood insurance policies. But New Jersey is a highly capitalized, wealthy area. Also, “there was an emphasis on the part of Governor [Chris] Christie to get [reconstruction] moving in a hurry” and rapidly recover the shore, because many of the shore communities depend on summer tourism, deriving 80% of their annual income between Memorial Day and Labor Day. As a result, “many had fully recovered within the first six months,” Cutter said. “These two examples illustrate how context and antecedent conditions in areas make a difference in the timing and the geography of recovery.”

Getting off the hazard loss ‘up escalator’

How do we resolve this hazard loss paradox—that despite knowing more, we are losing more? In her view, getting off the hazard loss ‘up escalator’ will depend on major cultural shifts both within policy groups and within hazard science, her third point.

“We know that hazard science can make a difference—if it is used,” Cutter said. One obstacle, she noted, is the aversion of some political leaders to anything scientific. “They view science simply as a belief system: it’s different from their belief system, and therefore it’s bad and meaningless.” That being said, she noted, there are increased efforts by science agencies to engage policy makers. One example is an international group called Integrated Research on Disaster Risk, which is trying to infuse disaster science into public policy.”

Second, “emergency management has to become management, not response,” Cutter stated. “And it has to become pro-active management, not after-the-fact response. That’s going to take a major cultural shift at the national, state, and local level. We need to base public policy on evidence, not expedient politics and who’s in charge of what committees. We need to think in the long term, not just the election cycle of two years or four years. That’s no way to manage risk or develop disaster policy. And the policy community needs to think of hazard researchers as their friends: We can give you good information on which you can base policy.”

“In turn, hazard researchers have to make their research available,” she continued. “Publishing your research in a refereed journal is nice but it goes nowhere. You need to develop ways to reach the policy community. They are not going to read a 10-page technical report; they may read a 1-pager with the technical details stripped out and the key messages in there. You need to solve the problems of the policy maker and practitioner. In fact, you need to go to them and ask what are their problems. Last—my favorite, having worked on IPCC [Intergovernmental Panel on Climate Change] reports—hazards researchers have to get over this thing that they can’t say anything because they are uncertain and don’t know the certainty bands. Instead, we have to think about what is good enough information for the policy maker to use to make a sound decision.”

“Both communities,” Cutter concluded, “need to keep in mind the broader long-term vision: the goals of equity, fairness, and the development of a more resilient future for the next generation. That's why we’re in this business in the first place.”

Susan L. Cutter is Distinguished Carolina Professor at the University of South Carolina and Director of the university’s Hazards and Vulnerability Research Institute. She has authored or edited thirteen books, more than 150 peer-reviewed articles and book chapters. Her latest book Hurricane Katrina and the Forgotten Coast of Mississippi examines the post-disaster recovery along the Gulf coast and the role that historic, economic, and social factors play in producing the differential recovery that is so apparent today.

© 2015 Trudy E. Bell

Next time: Explosion at Equality

Selected references

An audio file of Dr. Cutter’s Gilbert F. White Lecture in the Geographical Sciences given at the National Academy of Sciences as well as a PDF of all her slides are available here. (The audio recording begins on slide 6.) Warm gratitude is expressed to Dr. Cutter for allowing me to reproduce several of her slides.

More about the hazard loss escalator appears in the 2011 journal article
“The Unsustainable Trend of Natural Hazard Losses in the United States,” by Melanie Gall, Kevin A. Borden, Christopher T. Emrich, and Susan L. Cutter in Sustainability 3:2157-2181, based on data amassed in SHELDUS. .

Bell, Trudy E., The Great Dayton Flood of 1913, Arcadia Publishing, 2008. Picture book of nearly 200 images of the flood in Dayton, rescue efforts, recovery, and the construction of the Miami Conservancy District dry dams for flood control, including several pictures of Cox. (Author’s shameless marketing plug: Copies are available directly from me for the cover price of $21.99 plus $4.00 shipping, complete with inscription of your choice; for details, e-mail me), or order from the publisher.