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Grim Social Expectations for New Madrid Fault Earthquake
The Mid-America Earthquake Center at the University of Illinois at Urbana-Champaign, in partnership with other entities, has published its fine and useful Phase I report titled “Impact of Earthquakes on the Central USA” (released to the public November 20, 2008). (1) This careful engineering and social impact study begun in 20-06 vastly improves the knowledge base about possible future behaviors of the New Madrid Seismic Zone, thus providing for the first time a framework on which to anchor social plans to mitigate the suffering expected in the aftermath of the destruction. Interestingly, the report uses the term “risk” only twice in the main body of the report, preferring other terms (more below).
The Mid-America Earthquake Center is one of three national earthquake engineering research centers established and funded by the National Science Foundation and its partner institutions. It consists of a consortium of nine institutions, which together produce core research in consequence-based risk management, engineering engines, social and economic science, and information technology. (2) The Federal Emergency Management Agency (FEMA) funded the project through a grant from the US Army Corps of Engineers (Construction Engineering Research Laboratory) (W9132T-06-2), which managed the project. Other partners in the project included the Institute for Crisis, Disaster and Risk Management at George Washington University; the state geological survey organizations of eight states in the center of the US; the US Geological Survey; and the Central U.S. Earthquake Consortium (CUSEC, founded in 1983, headquartered in Memphis, Tennessee). (3) Innovative Emergency Management, a military and government contractor founded in 1985, and headquartered in Baton Rouge, Louisiana, provided overall Phase I project coordination. (4)
Authors of the report are Amr S. Elnashai (project principal investigator, Mid-America Earthquake Center at University of Illinois, Urbana-Champaign), Lisa Johanna Cleveland (technical project manager, University of Illinois), Theresa Jefferson (principal investigator, GW sub-contract, formerly of George Washington University), and John Harrald (co-principal investigator, formerly of George Washington University).
Professor Elnashai holds a bachelor of science (Cairo University 1977) in civil engineering, a master of science (Imperial College, London, UK 1980) in reinforced concrete structures, and a Ph.D. (Imperial College, London, UK 1984) in structural engineering. He has been on the faculty of the Department of Civil and Environmental Engineering at the University of Illinois, Urbana-Champaign, since 2001. He was the associate director of the Mid-America Earthquake (MAE) Center, with primary responsibility towards research coordination, from June 2001 to September 2003, when he became acting director. In 2004, he became the center’s director. Before joining the University of Illinois, he was professor of earthquake engineering and head of the Engineering Seismology and Earthquake Engineering Section at Imperial College (London, UK). Dr. Elnashai has been a Visiting Professor at the University of Surrey (UK) since 1998 where he maintains close ties. (5) Biographical information for Lisa Johanna Cleveland is not currently available. Theresa Jefferson earned her master’s degree in operations research and a doctor of science degree in engineering management at George Washington University. In August 2008, she moved from George Washington University where she was assistant professor in the Engineering Management and Systems Engineering Department since 2000, for Virginia Tech Center for Technology, Security, and Policy as a research professor. (6) John Harrald, Ph.D., earned his bachelor of science from the U.S. Coast Guard Academy, his master’s degree from the Massachusetts Institute of Technology, and his Ph.D. in management science from Rensselaer Polytechnic Institute. He recently (August 2008) left George Washington University for Virginia Tech Center for Technology, Security, and Policy as a research professor. (6) Scientists have learned in the past 25 years that earthquakes do not happen only in the western United States. Indeed, strong earthquakes have occurred repeatedly in the past in the central Mississippi Valley, also known as the New Madrid Seismic Zone. Several faults comprise this zone stretching from Marked Tree, Arkansas, to Cairo at the southern tip of Illinois. Earthquakes along the New Madrid Seismic Zone cause disruption in much larger areas than earthquakes of similar magnitude in the western United States. “For example, the San Francisco, California, earthquake of 1906 (magnitude 7.8) was felt 350 miles away in the middle of Nevada, whereas the New Madrid earthquake of December 1811 rang church bells in Boston, Massachusetts, 1,000 miles away. Differences in geology east and west of the Rocky Mountains cause this strong contrast.” (7) The New Madrid Seismic Zone is a circumscribed region in the central United States distinguished from adjacent parts by its geologic instability manifested by earthquakes, as described elsewhere. (8-9) This curious zone also goes by the names of the New Madrid Fault Zone, the New Madrid Fault Line, the New Madrid Rift Zone, the New Madrid Rift Complex, the Reelfoot Rift, and the Reelfoot Complex, among other appellations. The new report by Elnashai, et al., adds clarity to this mishmash of terms (more below). The New Madrid Seismic Zone is an intraplate seismic zone--smack dab in the center of the North American Plate—as opposed to the more familiar interplate seismic zones, such as California’s San Andreas Fault Zone, which mark transform boundaries between tectonic plates. (8)
The term “New Madrid” comes from the town of New Madrid (pop. 3,000 and declining), Missouri, which was at or near the epicenter of the infamous earthquakes of 1811-1812, which experts believe were of magnitude 8. The magnitudes were determined based on witness reports at the time of the events, liquefaction features, such as sand blows, that observers can still view dating from the event, and fault structure. “At the time of these earthquakes, the Central U.S. was sparsely populated, with very few structures. Of the few buildings constructed in the region, many were likely for residential or agricultural use and of low quality. Currently, however, the Central U.S. is vastly populated with major population centers in Memphis, Tennessee and St. Louis, Missouri. Both of these cities are likely to sustain damage from a New Madrid Seismic Zone event, and Memphis in particular could see severe damage,” note the authors. (10) The little town of New Madrid, Missouri, still exists on the west shore of a loop of the Mississippi River. The term “Reelfoot” comes from the Reelfoot Lake formed during the New Madrid earthquakes of 1811 and 1812 when the Mississippi River overflowed its eastern banks, diverting water into a shallow depression. Reelfoot Lake, in turn, was named after Chief Reelfoot of the Chickasaw tribe memorialized in an Indian legend that ties together his clubfoot and earthquakes in the region. (8-9) The chance of a magnitude 6 or 7 earthquake occurring within the next 50 years along the New Madrid Seismic Zone is roughly 90%. Additionally, more than 3,000 earthquakes have occurred in the New Madrid Seismic Zone since 1974. (10) In April 2008, an earthquake occurred near Mt. Carmel, Illinois, along the Wabash Valley Fault in southern Illinois. The eight states at risk of harm from a New Madrid Seismic Zone event are Alabama, Arkansas, Illinois, Indiana, Kentucky, Mississippi, Missouri, and Tennessee. The Mid-America Earthquake Center study also assessed two nearby earthquake zones, the Wabash Valley Seismic Zone in southern Illinois and southeast Indiana and the East Tennessee Seismic Zone in eastern Tennessee and northeastern Alabama, whose discussion is beyond the scope of this report. The report cleverly marries eight scenarios to the eight states to “provide scientifically credible, worst case damage and loss estimates for the purposes of emergency planning, response and recovery.” (11) This novel approach combines geological realities with geopolitical entities. The study is an aggregate of eight individual studies corresponding to the eight individual states at risk from an earthquake event in the New Madrid Seismic Zone. For example, the scenario for the Illinois New Madrid Seismic Zone event is a magnitude 7.7 earthquake (magnitude suggested by the U.S. Geological Survey) caused by a rupture of the northeast extension of the New Madrid Fault, which produces intense shaking in southern Illinois. The report identifies the forty Illinois counties nearest to the fault that are expected to incur high levels of damage in a 7.7 earthquake event, thus providing an evidence-based approach to allocation of state and county planning and response resources.
Elnashai, et al, divide the primary New Madrid Seismic Fault into three segments: the northeast segment, the reelfoot thrust, and the southwest segment. “The northeast and southwest segments are strike-slip faults while the central, or reelfoot, segment is a thrust fault…The ground motion maps developed for the New Madrid Seismic Zone are based on the rupture of a single segment, meaning the northeast, central and southwest segments are independent events which model the rupture of the entire fault segment length. Ground motion for each segment rupture is attenuated through rock and then propagated through the layer of soil on top of the bedrock layer.” (10) As noted earlier, the Mid-America Earthquake Center report shied away from the term “risk” for unknown reasons and uses three other elements to measure earthquake impact; namely “hazard,” “inventory” and “fragility.” The authors used HAZUS-MH MR2 for inventory data for all three categories over the eight-state region. The HAZUS building data classifies structures by building/construction type and occupancy of building use type. There are 33 occupancy types, including residential, commercial, industrial, government, educational, agricultural and religion, and 36 building types, including wood frame, concrete, steel, precast concrete, unreinforced masonry, reinforced masonry and mobile homes. The authors used information from the Homeland Security Infrastructure Program (HSIP) 2007 Gold Dataset (NGA Office of America 2007) for critical infrastructure. (14) The infrastructure components that the authors supplemented with HSIP data are:
*The authors added natural gas and oil major transmission pipelines (which were not part of the HAZUS-MH MR2 default inventory) as a new type of inventory. (15)
The beauty of this study is that it does not stop at quantifying damage to infrastructure from a magnitude 7.7 earthquake along the three segments of the New Madrid Fault, but assesses the impact of carefully quantified infrastructure degradations on human populations. The authors write, “Social impacts include a wide variety of requirements associated with a population in a post-disaster environment. HAZUS-MH MR2 encompasses several estimates including displaced households (residences and families), short-term shelter population, and casualties. The number of displaced households is estimated based on the extent of damage to residential buildings along with building classification (single family, multi-family dwelling)…Estimates for the number of people seeking shelter are calculated as a percentage of the displaced population, taking into consideration demographic composition factors including ethnicity, age, and income level. These demographic factors influence the number of families seeking shelter in a region. For example, those families with limited financial means are more likely to seek public shelter and require short-term housing.” Furthermore, social impact models “include more detailed predictions for the displaced population. Food, refrigeration, sleeping and water requirements are determined as well as space requirements for housing the shelter seeking population…The percentage of the displaced population requiring medical attention for chronic illnesses is estimated and can be included in response plans.” Casualty estimates in the HAZUS-MH- MR2 approach include all injuries and fatalities when reporting a total number. Four levels of casualties range from minor injuries not requiring hospitalization to fatalities. The authors found mistakes in the HAZUS-MH-MR2 methodology to derive the number of displaced people and the shelter seeking operation, but were able to work around the error. (1) For each of the eight states in the New Madrid Seismic Zone, Amr S. Elnashai, et al, wrote up a scenario, including damage to buildings and damage and functionality of “essential facilities” (see above), transportation lifelines, and utility lifelines. They go farther to identify the counties that will experience the most significant shaking and damage. Here we limit review to an earthquake event in Missouri. (Tennessee experiences the most damage of all the states in the Zone.) The earthquake event on the central thrust fault will produce substantial shaking in southeast Missouri, affecting 45 counties and the City of St. Louis. “Missouri is one of the most heavily damaged states of all the states in the New Madrid Seismic Zone region,” declare the authors. “Of the 1.9 million buildings in Missouri, nearly 122,000 buildings are at least moderately damaged, which equates to 6.5% of all buildings in Missouri…Nearly 98% of all cases of complete damage are experienced by residential structures…Wood frame structures unreinforced masonry buildings, and mobile homes experience the most damage…Nearly 200 schools and over 100 fire stations are at least moderately damaged. In addition, numerous facilities are completely damaged and will not be operational for an extended period of time. The day after the earthquake, 37 hospitals, nearly 300 schools, 67 police stations and 135 fire stations are not functioning…Much of southeast Missouri is without local emergency response services and medical care.” “The extensive damage to transportation lifelines makes traveling within southeast Missouri incredibly difficult…[O]ver 650 highway bridges are completely damaged and over 1,350 bridges are not operational immediately after the earthquake. Most bridges are in the counties that experience substantial, essential facilities functional losses and these counties were listed previously. Numerous railway, port and airport facilities are also damaged. This level of damage leads to 26 airports, 25 ports and 16 railway facilities out of service in the days immediately following the event. With much of this damage and functional loss occurring in southeast Missouri, not only will it be difficult to travel within this area, but it will be much harder to get relief workers and aid into the area and injured or displaced families out of the area. “Utility lifelines are heavily damaged as well, particularly in southeast Missouri. Approximately 50 potable water facilities are completely damaged and over 650 facilities are not operating the day after the event. Communication facilities also incur major damage, with nearly 1,600 at least moderately damaged facilities and 865 non-functioning facilities immediately after the earthquake. In addition, over 100 electric power facilities are down and 63 natural gas facilities are not operating. Most of southeast Missouri is so heavily damaged that nearly all utility services are down in the days after the event.” “This massive loss of functionality in utility lifelines leads to hundreds of thousands of service interruptions…Nearly 150,000 households are without potable water and 100,000 without electricity immediately after the earthquake. After one week, many customers will see service restored, though 80,000 households are still without water and 40,000 without electricity. Even after one month, tens of thousands of customers are without water, electricity or both. Such major lapses in service will most likely prevent people from remaining in their homes causing them to seek temporary, or even long-term, shelter at public sheltering locations.” (18) Here we describe the social impact and direct economic loss for the state of Missouri, although the state of Tennessee incurs the most harm from an earthquake event, as described elsewhere. (19) “The central segment event generates six million tons of debris in the State of Missouri. Steel and concrete buildings account for 3.1 million tons of debris, while brick, wood and building contents comprise the remaining 2.9 million tons. A total of 240,000 truckloads with a 25-ton truck are required to remove all the debris created by this earthquake. Missouri is one of the most catastrophically impacted states in the NMSZ zone with regard to social impacts and economic losses…[N]early 122,000 people are displaced, which is far more than any other scenario discussed previously [only Tennessee has more displaced people]. Nearly all displaced residents reside in the critical counties in southeastern Missouri. Approximately 36,700 people seek temporary public shelter after the NMSZ event. Substantial amounts of space are required to house all those displaced. Nearly 18 million square feet of space is required, while 1.3 million gallons of water and over 500,000 MREs [meals ready to eat] are needed in the first week to care for the sheltered population.” “The tens of thousands of damaged buildings cause nearly 16,000 casualties, with most The Elnashai study correctly points out that states and counties not struck by the earthquake will likely remain deeply involved in response. For example, with many hospitals not functioning in the harder hit areas, medical facilities outside the critical counties are more likely to be operational immediately after the event and thus able to care for the injured. In addition, the operational facilities closest to the heavily damaged counties will likely need to care for victims evacuated from the critical counties in the first hours and days after the earthquake. (21) The authors write, “Some states are more likely than others to incur substantial casualties and economic loss based on their location in relation to the source of rupture. Southern states such as Alabama and southern Mississippi show very few casualties, if any, and minimal economic losses. As a result, these areas will be more likely to provide supporting services to heavily impacted areas after the earthquake. Such services may include sheltering displaced populations, providing medical services at functioning hospitals and providing staging areas for rescue and aid workers. The same is true for northern Illinois and most of Indiana. These states, or portions of states, see very few casualties or displaced residents. Such areas will be able to provide similar services to more northern areas that are heavily damaged from a NMSZ event.” (22) “The counties nearest to the source of seismic activity are likely to experience substantial damage to buildings as well as loss of critical services. This means that tens of thousands of homes will be damaged and residents will be displaced. For an earthquake nucleating in the northern portion of the NMSZ zone, thousands of buildings in southern Illinois and portions of Missouri and Kentucky will be damaged and tens of thousands will be without homes. The same is true for a southern NMSZ event, though in this case the heavily damaged areas will be northeast Arkansas, northwest Mississippi, western Tennessee and portions of western Kentucky. In addition, Memphis, TN, will be heavily damaged and its large number of highly vulnerable unreinforced masonry buildings will be significantly affected. This southern segment earthquake is likely to damage the greatest number of homes and affect the largest number of people when considering each individual segment rupture in the NMSZ. Critical infrastructure and lifelines will also be heavily damaged and will be out of service after the earthquake for a considerable period of time. Such mass outages are likely to affect a region much larger than the 8 states studied above. Many hospitals nearest to the rupture zone will not be able to care for patients, indicating that those injured during the event will have to be transported outside of the region for medical care. Moreover, pre-earthquake patients will have to be moved out of the area to fully functioning hospitals. It is doubtful that the transportation system will be functioning to a level that allows such mass evacuation. Police and fire services will be severely impaired due to damage to stations throughout the impacted region. Many schools that serve as public shelter will be damaged and unusable after the earthquake. Transportation into and out of the areas near the fault rupture will be difficult if not impossible. Many bridges will be damaged and not passable, airports will be damaged and some ferry facilities and ports will be out of service. The massive loss of functionality of transportation systems and facilities will prevent displaced residents from leaving the region and also make it difficult for ground-transported aid workers and relief supplies to access the most heavily damaged areas. Utility services will be severely disrupted for hundreds of thousands of customers due to extensive facility and pipeline damage. Extended service outages will be highly likely for tens of thousands of customers, making it difficult for them to remain in their homes, even if they are structurally sound after the earthquake. Damage to major natural gas and oil transmission lines will lead to service interruptions that will affect areas as far away as the east coast and New England. Social impact estimates show that hundreds of thousands of people will be displaced and Areas nearest to the rupture will be heavily damaged and many transportation and utility lifelines will not function for an extended period of time. The parts of each state that are farthest from the rupture will remain largely undamaged and functioning. Expectations are that these undamaged regions will support the response and recovery of the severely damaged areas. In addition, Indiana and Alabama are not likely to experience significant damage from a NMSZ event and may also function as host states in the aftermath of a NMSZ earthquake.” (23) The authors list ten pressing research and development “products.” The eighth and ninth in the list follow: “During the response phase of the disaster management cycle, the prioritization of service needs will change. Over time focus will move from life-saving to life sustaining and finally life-supporting. The uncertainty regarding the length of time that will be required to deliver services during a catastrophic event is very high. The transition from response to recovery takes much longer during a catastrophe. Midterm economic effects are prolonged due to factors such as loss of infrastructure, loss of jobs, etc. More research is needed on speed-of-recovery factors of the socioeconomic systems. The response models currently focus on immediate responses and are not validated for longer time frames. Consideration of long term commodity distribution, medical services, and repair of cascading infrastructure failures is required. “Current preparedness goals are based on establishing adequate response system capabilities. The objective of response should be to successfully achieve observable and measurable goals. In order to do this, response managers must achieve critical success factors and avoid critical failures. The outcome-based metrics required to establish goals and to manage for success do not exist. The modeling and estimation of disaster caused needs conducted in this project can provide the basis for establishing these metrics and for developing outcome-based response strategies.” (24) The authors’ concluding paragraph reads, “In general, disasters that lead to catastrophic consequences produce cascading infrastructure failures which may result in unanticipated response requirements. Infrastructure failures not only influence the demands for service but also the mobility and capabilities of response organizations attempting to provide these services. There is a dearth of information on the manner in which people and systems behave following a catastrophe. There is a pressing need for collection and assimilation of such information possibly from other regions in the world with social and economic characteristics similar to the Central USA.” (24) The Elnashai study is laudable for its clarity, reach, transparency and innovation. It has moved the New Madrid Seismic Zone topic area far forward in delineating with great specificity what the intergovernmental and private sectors will face when the earthquake fault in the New Madrid Seismic Zone gives way again. There can be no hiding from this data by the federal government, states and counties located closest to the three segments of the New Madrid Fault. The eight states at risk for harm from a large earthquake in the New Madrid Seismic Zone will not be alone in their suffering from an earthquake’s impact. As integral economic and social units of the U.S., their distress will ripple outward to involve by degrees the rest of the nation. For example, an earthquake damaging Tennessee will be a nationwide catastrophic event, predict some experts, largely due to the interruption in transportation, communications, fuel supply, and other economic consequences that would be experienced as a result of damage to the infrastructure. (25) Notes: |
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