Prospects for Critical Infrastructure
Thomas D. O’Rourke
Critical infrastructure needs have changed significantly both in the wake of disasters such as the terrorist attacks of 9/11 and Hurricane Katrina and as a result of emerging technologies. It is important to understand critical infrastructure’s interdependencies, high-tech opportunities, and the need for long-term investments. Other key aspects are interoperability, real-time monitoring, intelligent networks, and effective modeling and simulation. Underlying all of these is the necessity of communication and education among the various stakeholders—utilities, federal and local governments, businesses, communities, and, of course, engineers!
The concept of critical infrastructure is evolving. In the 1980s, the National Council on Public Works Improvement (1988) concentrated on public sector infrastructure, such as highways, roads, bridges, airports, public transit, water and wastewater facilities, and municipal/hazardous waste services. In the 1990s, the core concept of infrastructure was redefined in terms of national security. After 9/11, the number of “critical” infrastructure sectors and key assets listed in the National Infrastructure Protection Plan1 was expanded
1 The Department of Homeland Security’s 2009 National Infrastructure Protection Plan is available at www.dhs.gov/xlibrary/assets/NIPP_Plan.pdf.
and now includes 16 sectors: chemical; commercial facilities; communications; critical manufacturing; dams (including locks and levees); defense industrial base; emergency services; energy; financial services; food and agriculture; government facilities; health care and public health; information technology; nuclear reactors, materials, and waste; transportation systems; and water and wastewater systems (Federal Register 2013).
The national protection plan defines a broad spectrum of assets in need of security, which is complex and unwieldy with respect to unifying concepts and modeling for engineering purposes. In contrast, the concept of a “lifeline,” developed by the Technical Council on Lifeline Earthquake Engineering to evaluate the performance of large, geographically distributed networks during earthquakes (O’Rourke 2007), involves a smaller number of critical systems—electric power, gas and liquid fuels, telecommunications, transportation, waste disposal, and water supply. If flood and hurricane protection systems are added, one can identify a subset of seven geographically distributed networks that are intimately linked with the economic well-being, security, and social fabric of the communities they serve. Thinking about critical infrastructure through this subset of lifelines helps clarify common features and provides an effective framework for understanding interdependencies among the different systems.
Hurricane Katrina in 2005 challenged the 9/11 paradigm of protection of critical infrastructure. The hurricane protection system (HPS) of New Orleans was authorized by the US Congress under the 1965 Flood Control Act, and its design and construction were supervised by the US Army Corps of Engineers. But when Hurricane Katrina struck, the HPS was incomplete and no parish had the full level of protection authorized in 1965. As the Interagency Performance Evaluation Task Force concluded, the HPS “did not perform as a system”; it had been constructed in a piecemeal fashion over many years that represented a history of “continuous incompleteness” (IPET 2008).
A new paradigm emerged after Hurricane Katrina, centered on the concept of resilience, and much has been written and discussed about this concept. In current parlance, the resilience of an organization or community is an overarching attribute that reflects its degree of preparedness and ability to respond to and recover from shocks. The term has become the scaffolding on which to build a community or organization that is well prepared and responsive to a wide range of demands, including natural hazards and human threats. Current US policy for critical infrastructure is an amalgam of concepts and activities based on the development of community resilience and the protection of critical infrastructure.
CRITICAL INFRASTRUCTURE IN THE 21ST CENTURY
Critical infrastructure is shaped and characterized by three specific features. First, much of it, especially in cities, is located underground, where it is removed from direct observation unless uncovered, and its state of repair and proximity to other structures is often unknown. Urban congestion increases risk due to the close proximity of many pipelines, cables, and supporting facilities. Damage to one facility, such as a cast iron water main, can cascade rapidly into damage in surrounding facilities, such as electric and telecommunication cables and gas mains, with systemwide consequences.
Interoperability is another key feature of modern infrastructure. Electric power, natural gas, water, oil, telecommunications, and transportation are all interdependent, as illustrated in Figure 1. Electric power is essential for the reliable operation of virtually all other infrastructure systems. During extreme events electric power is, in effect, the gateway for local damage to escalate or cascade into other systems. Telecommunications are used for surveillance and control of virtually all lifeline networks, and will become increasingly important as information technologies are improved for
FIGURE 1 Infrastructure Interoperability (after Peerenboom, Fisher, and Whitfield 2001). SCADA = supervisory control and data acquisition.
network monitoring and operations. Transportation is necessary for moving people and resources and, after extreme events, crucial for emergency response and recovery. Many communities have come to recognize that critical infrastructure also supports economic well-being and therefore must be part of policy and planning for business continuity.
The third key feature is institutional fragmentation. Much infrastructure is not only institutionally balkanized—independent organizations are responsible for electric power, telecommunications, water supplies, transportation, waste conveyance and treatment, and gas and liquid fuel delivery—but also divided between public and private ownership. This compartmentalization makes it all but impossible to develop a unified approach.
Proper management of infrastructure requires an understanding of the different institutional and corporate cultures that are the basis for working relationships, competition, employee incentives, and levels of service.
Modern Tools and Needs
Critical infrastructure in the 21st century will involve radical improvements in real-time monitoring, intelligent networks, remote sensing capacities, and complex system modeling and simulation.
One example of emerging technology for intelligent infrastructure involves fiber optics technology. Brillouin optical time domain reflectometry (BOTDR; Figure 2) for infrastructure monitoring has been applied successfully to monitor construction effects on tunnels, pipelines, and buildings (Klar and Linker 2010; Mair 2008). The BOTDR technology involves the precise measurement of phase shifts in light frequency (a single optical fiber 30 km long can resolve strains to 10 microstrain). BOTDR can monitor changes in temperature and pressure over very large distances, and is thus akin to a “smart” skin for geographically distributed infrastructure such as highways, bridges, pipelines, and tunnels.
System performance is important for at least three main reasons (O’Rourke 2010). First, it provides the basis for planning and engineering at a scale commensurate with large, geographically distributed effects. Second, it is the logical extension of integrated component behavior, and for a network represents the ultimate expression of performance in terms of diverse environmental effects. Third, it provides the only way by which managers and engineers can gauge the scale and regional impact of network behavior. System performance sets the stage for quantifying the regional economic
FIGURE 2 Fiber Optics for Intelligent Infrastructure (after Klar 2012)
consequences and community impact of an earthquake as well as planning for emergency response and system restoration.
The current generation of hydraulic network models for large, geographically distributed water supplies has evolved sufficiently that engineers and managers can use them to plan and design for complex performance under the highly variable and uncertain conditions associated with geohazards. For example, the Los Angeles Department of Water and Power has developed a decision support system based on an accurate simulation of its 12,000 km of pipelines and related facilities (O’Rourke 2010). The system comprehensively accounts for seismic and geohazards as well as the interactions among water, electric, social, and economic impacts to produce a multimodal simulation of earthquake effects, ground failures, accidents, and human threats (Figure 3).
Simulations for different scenarios allow system personnel to visualize a wide range of responses for an entire system or a specific part of that system. By running multiple scenarios, with and without modifications of the system, engineers and managers can identify recurrent patterns of response and develop an overview of potential performance, helping them plan for many eventualities and improving their ability to improvise and innovate during an extreme event.
FIGURE 3 Diagram of Los Angeles Department of Water and Power Multimodal Simulation
The plan that emerges from any particular suite of scenarios, however, is not as important as the planning process itself, because as a disaster unfolds, the reality of the event will diverge from the features of the most meticulously designed scenario. With good planning, however, emergency managers and lifeline operators can improvise, and skilled improvisation enables emergency responders to adapt to field conditions.
Investment and Financing
Sustaining critical infrastructure requires adequate financial resources and a long-term commitment to finishing complex projects. Consider, for example, the New York City water supply, which is delivered by City Water Tunnel 1 (commissioned in 1917) and City Water Tunnel 2 (commissioned in 1935). The state of repair of both tunnels can only be inferred from indirect evidence because neither can be dewatered for inspection.
A third water tunnel is crucially important so that each of the first two tunnels can be taken out of service, inspected, and repaired. The construction of City Water Tunnel 3 began in 1970 and is scheduled to open in 2013. The
new tunnel will require nearly 100 kilometers of tunneling over a period of five decades at an estimated total cost of more than $6 billion. This project is indicative of the size, financial requirements, and time frame associated with many critical infrastructure projects.
The problems of aging US infrastructure are so severe that the traditional sources of public funding—taxes, bond issues, and tolls—are no longer adequate to meet national and regional needs. Sufficient liquidity is lacking in conventional public works financing to address rehabilitation and new construction. It is therefore crucial to attract private equity by developing alternative financing mechanisms, such as public-private partnerships and infrastructure banks, to expand and reinforce conventional fundraising mechanisms for infrastructure projects.
Information and Information Technology
From an engineering and scientific viewpoint, there has never been a more opportune time for advancing the state of the art and practice for characterizing and modeling complex infrastructure systems. Advanced geographical information systems, remote sensing, condition monitoring, model-based simulation, and systems engineering coupled with the capability of producing precise digital base maps, which can integrate the spatial characteristics of infrastructure, provide unparalleled opportunities.
To benefit from the enormous power of information technology, however, it is necessary to have access to information. Since 9/11 severe restrictions have been imposed on access to information about critical US infrastructure. Although these restrictions are based on legitimate concerns about security, they may become serious barriers to innovation unless we have suitable procedures for information accessibility and dissemination. It is extremely important to develop a consistent policy regarding the need to know vs. the need to secure information and databases about critical infrastructure.
Involvement of Engineers
Solutions to infrastructure require engineering input that is often absent or underrepresented when experts are convened to develop strategic plans and policies for urban centers. A survey of recent conferences provides some interesting statistics. At a 2011 conference in New York City sponsored by the Economist, entitled “Intelligent Infrastructure,” less than 10 percent of
the invited speakers were engineers. At a conference sponsored by Chatham House, entitled “The Future of Cities 2011,” there were no engineers among the 28 speakers. The meetings convened by the Rockefeller Center to produce the influential publication Century of the City involved only three engineers among approximately 300 participants.
Solutions for infrastructure are often advanced independently by planners and engineers. Conferences about cities and infrastructure convened by engineers generally do not include planners or significant representation of applied social scientists. Similarly, engineers are frequently underrepresented at conferences of planners and urban policymakers.
Clearly, more interdisciplinary dialogue is needed. The problems of critical infrastructure are suffused by social and technical issues that require close collaboration between engineers and applied social scientists.
US policy and practice for critical infrastructure have been shaped by 9/11 and Hurricane Katrina to protect critical facilities and support resilient communities. The emphasis on resilience has been growing, and in the wake of Superstorm Sandy has concentrated on coastal communities and the consequences of global climate change. It is likely that the concept of community resilience will evolve over time, similar to the way our awareness and policy formulations have changed with respect to critical infrastructure.
We are challenged to redefine infrastructure in terms of resilience, focusing on engineering and social science collaboration. The most promising prospects for improved infrastructure include understanding and managing interdependencies, reducing the constraints of institutional fragmentation, harnessing sensor and monitoring technologies to create “smart” systems, modeling complex networks, developing long-term financing mechanisms that attract private equity, and leveraging the power of information technology with improvements in access to and use of information about critical infrastructure.
Federal Register. 2013. Review and Revision of National Infrastructure Protection Plan. Available at https://www.federalregister.gov/articles/2013/06/06/2013-13427/review-and-revision-of-the-national-infrastructure-protection-plan#h-10.
IPET [Interagency Performance Evaluation Task Force]. 2008. Performance Evaluation of the New Orleans and Southeast Louisiana Hurricane Protection System. Final Report. US Army Corps of Engineers. Available at https://ipet.wes.army.mil/.
Klar A. 2012. Presentation at Technion-Cornell Joint Research Built Environment Workshop, October 15–16, New York.
Klar A, Linker R. 2010. Feasibility study of an automated detection and tunnel excavation by Brillouin optical time domain reflectometry. Tunneling and Underground Space Technology 25:575–586.
Mair RJ. 2008. Tunneling and geotechnics: New horizons. Geotechnique 58(9):695–736.
National Council on Public Works Improvement. 1988. Fragile Foundations: A Report on America’s Public Works. Final Report to the President and Congress. Washington: US Government Printing Office.
O’Rourke TD. 2007. Critical infrastructure, interdependencies, and resilience. The Bridge 37(1):22–29.
O’Rourke TD. 2010. Geohazards and large geographically distributed systems. Geotechnique 60(7):503–543.
Peerenboom J, Fisher R, Whitfield R. 2001. Recovering from disruptions of critical independent infrastructures. Presented at the CRIS/DRM/IIT/NSF Workshop on Mitigating the Vulnerability of Critical Infrastructures to Catastrophic Failure, Washington. September.