CHAPTER THREE

Current Dam and Levee Infrastructure, Management, and Governance

This chapter summarizes current dam and levee physical infrastructure, and management approaches with respect to safety, including methods and standards used in design, inventory, operation and maintenance, and emergency management. It also addresses the governance framework in place to facilitate and guide dam and levee safety, including the legal framework and the roles and authorities of agencies at different levels. Gaps in current practice and governance related to fostering community resilience are identified. Because policies, management, and jurisdictional responsibility for safety differ between dams and levees, this chapter describes dam and levee issues separately.

“Safety” to many dam and levee professionals is associated primarily with reducing the likelihood of flooding. Dam safety efforts since the 1972 failure of Buffalo Creek Dam1 have therefore focused on strengthening safety programs, reducing the potential for future failures, conducting periodic inspections, remedying deficiencies, and preparing emergency action plans (EAPs). Progress in those endeavors has been substantial on a national scale. There has also been consistent movement in recent years toward risk-informed dam safety assessments among many dam owners. Development of EAPs and the carrying out of tabletop and full-field exercises have also become established dam safety practices among many owners.

Despite such challenges as limitations in safety program resources, a large number of dams rated as having “high” or “significant” potential of death or loss of property in the event of failure (see Box 3.1for description of the rating system) are inspected in a timely ­manner according to guidance from the Association of State Dam Safety Officials (ASDSO)2 (e.g.,

_____________

1Information about the Buffalo Creek Dam failure can be found at www.wvculture.org/history/disasters/buffcreekgovreport.html (accessed December 23, 2011).

2ASDSO was established in 1983 and represents state, federal, and local dam professionals, academics, and manufacturers and suppliers. The organization was established to provide guidance for nonfederal dam owners. Although it holds no regulatory authority, it has played a major role in coordinating dam safety efforts across the country and between the states and the federal agencies. It has been the major advocate for dam safety policy, technical guidelines, and training. See www.damsafety.org/about/?p=1ca717dd-18d5-4803-a7eb-cd45aad31210 (accessed February 7, 2012).



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CHAPTER THREE Current Dam and Levee Infrastructure, Management, and Governance This chapter summarizes current dam and levee physical infrastructure, and manage- ment approaches with respect to safety, including methods and standards used in design, inventory, operation and maintenance, and emergency management. It also addresses the governance framework in place to facilitate and guide dam and levee safety, including the legal framework and the roles and authorities of agencies at different levels. Gaps in current practice and governance related to fostering community resilience are identified. Because policies, management, and jurisdictional responsibility for safety differ between dams and levees, this chapter describes dam and levee issues separately. “Safety” to many dam and levee professionals is associated primarily with reducing the likelihood of flooding. Dam safety efforts since the 1972 failure of Buffalo Creek Dam1 have therefore focused on strengthening safety programs, reducing the potential for future failures, conducting periodic inspections, remedying deficiencies, and preparing emergency action plans (EAPs). Progress in those endeavors has been substantial on a national scale. There has also been consistent movement in recent years toward risk-informed dam safety assess- ments among many dam owners. Development of EAPs and the carrying out of tabletop and full-field exercises have also become established dam safety practices among many owners. Despite such challenges as limitations in safety program resources, a large number of dams rated as having “high” or “significant” potential of death or loss of property in the event of failure (see Box 3.1 for description of the rating system) are inspected in a timely manner according to guidance from the Association of State Dam Safety Officials (ASDSO)2 (e.g., Information about the Buffalo Creek Dam failure can be found at www.wvculture.org/history/disasters/buffcreek 1 govreport.html (accessed December 23, 2011). ASDSO was established in 1983 and represents state, federal, and local dam professionals, academics, and manu- 2 facturers and suppliers. The organization was established to provide guidance for nonfederal dam owners. Although it holds no regulatory authority, it has played a major role in coordinating dam safety efforts across the country and between the states and the federal agencies. It has been the major advocate for dam safety policy, technical guidelines, and training. See www. damsafety.org/about/?p=1ca717dd-18d5-4803-a7eb-cd45aad31210 (accessed February 7, 2012). 49

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE BOX 3.1 Dam and Levee Hazard Classification The National Inventory of Dams (NID) hazard classification system (see Table 1) is broad, qualitative, and based on the potential threat to life and property in the event of dam failure. The criteria for inclusion in the inventory are provided in Table 2. A dam is given a “high” hazard rating if its failure can result in fatalities, whether the dam is small or large and has the potential for a single or thousands of fatalities. The rating is also regardless of its condition (e.g., its likelihood of failure). Current emphasis is appropriately on high-hazard dams, but there can be a wide disparity in the consequences of failures of these structures. Other consequences of dam failure, such as economic and environmental losses, are qualitatively evaluated TABLE 1 Hazard Classification for Dams Likelihood of Economic, Environmental, or Hazard Classification Likelihood of Loss of Human Life Lifeline Loss Low None expected Low and generally limited to owner Significant None expected Yes High Probable; one or more expected Yes (but unnecessary for this classification) SOURCE: FEMA (2004b). ASDSO, 2005). As a result of these inspections, many dams have undergone safety modifi- cations for hydrologic, seismic, and other deficiencies. But efforts to improve dam safety are not complete; about half of the dams that should have EAPs do not (Altinakar et al., 2008; see Box 3.2), and there is a backlog of safety repairs to be addressed. Moreover, improving safety needs to be a continuing and adaptive process that is responsive to changing structural and societal conditions. The concept of safety among dam and levee professionals has not evolved beyond reducing the likelihood of failure. DAM AND LEVEE INFRASTRUCTURE Before a community can address risks associated with dam or levee failure, it must know that a dam or levee is present and poses risk. Information on dam and levee loca- tion, physical properties (e.g., size and type), design requirements, ownership, maintenance responsibility, and regulatory framework is critical for understanding the hazards and risks 50

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Current Dam and Levee Infrastructure, Management, and Governance and defined in equally broad terms. The hazard classification process does not include an assessment of the sociological or other effects on a community, nor does it consider the broader local and regional effects (economic and other) of the loss of a critical infrastructure (power, water supply, flood protection). Hazard classification is assigned primarily by state or federal regulatory agencies. The Federal Emergency Manage- ment Agency guidance states that classifications “should be based on the worst-case, probable scenario of failure or mis-operation of the dam, i.e., the assigned classification should be based on failure consequences that will result in the assignment of the highest hazard potential classification of all probable failure and mis-operation scenarios” (FEMA, 2004b, p. 7). TABLE 2 National Inventory of Dams, Dam or Reservoir Size Criteria Categorya Criteria Excluded Dam height Over 25 ft 6 ft or lower, regardless of reservoir capacity Reservoir size At least 50 acre-ft Maximum, 15 acre-ft or less, regardless of dam height Hazard Any dam that poses a “significant threat to hu- man life or property in the event of its failure” Height is measured from the dam crest to the downstream toe; size is reservoir impoundment capacity. a SOURCE: USACE (2011a). associated with the infrastructure. The National Inventory of Dams (NID) and the National Levee Database (NLD) were established to provide information about dams and levees in the country. The next sections describe those inventories and information in them about dam and levee physical infrastructure and ownership. National Inventory of Dams The National Dam Inspection Act of 1972,3 passed after the failure of multiple dams, required the U.S. Army Corps of Engineers (USACE) to create the NID. The first ver- sion of the NID was delivered in 1975, and is generally updated on a 2-year cycle (the last update was in 2009).4 Since 1975, the NID has been managed by USACE or the Federal See Public Law 92-367 (available at npdp.stanford.edu/ndia.html). 3 See damsafety.org/media/Documents/PDF/2009NIDupdate_March2010.pdf. 4 51

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE BOX 3.2 Emergency Action Plans An Emergency Action Plan (EAP) identifies the actions and responsibilities of different parties in the event of an emergency, including uncontrolled flow from a reservoir or other controlled waters. As defined by FEMA (1998, p. 3), an EAP for a dam is a formal document that identifies potential emergency conditions at a dam and specifies pre-planned actions to be followed to minimize property damage and loss of life. The EAP specifies actions the dam owner should take to moderate or alleviate the problems at the dam. It contains procedures and information to assist the dam owner in issuing early warning and notification messages to responsible downstream emergency management authorities of the emergency situation. It also contains inundation maps to show the emergency management authorities the critical areas for action in case of an emergency. The requirements for EAPs are established by dam safety regulatory agencies at the national level, by such individual agencies as the Federal Energy Regulatory Commission, or by individual states. Figure 1 indicates that 48 percent of high-hazard dams that should have EAPs do not (Altinakar et al., 2008). Figure 2 indicates that about 71 percent of significant-hazard dams do not have EAPs (Altinakar et al., 2008). EAP oversight occurs pri- marily at the state level, but EAPs are examined by the Association of State Dam Safety Officials and the National Dam Safety Review Board. The latter two organizations have no authority to mandate revisions of EAPs to make them more effective, and state agencies often operate under tight budgets, making EAP oversight a challenge. Nevertheless, EAPs serve important functions for the dam owners and the broader community. Consequences of not having an EAP have been demonstrated, for example by the 1982 failure of the Lawn Lake Dam in the Rocky Mountain National Park in Colorado which caused the deaths of three people and $31 million in damage (NPS, 2004). A district court found that the government “in creating this relationship with citizens, also creates a duty for itself to develop orderly procedures for dealing with emergencies.”a EAP effectiveness is dependent on the correctness of the underlying assumptions (e.g., accurate estimation of risks and appropriate responses), reasonable care in the regular review and modification of plans, and ap- propriate education and training of those with responsibility in the execution of the plan. See Coates v. United States, 612 F. Supp. 592 (C.D. Ill. 1985). a 52

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Current Dam and Levee Infrastructure, Management, and Governance FIGURE 1 (a) Classification of high-hazard dams by height vs status of EAPs. (b) Classification by age vs status of EAPs. Based on entries in National Inventory of Dams as of September 28, 2008. Y = Yes, EAP exists; NR = EAP not required; and N = No, EAP does not exist. SOURCE: Modified from Altinakar et al. (2008). Used with permission from the authors, copyright 2012. Figure 1A in Box 3.2 Figure 1B in Box 3.2 Bitmapped, Bitmapped, low-res low-res FIGURE 2 (a) Classification of significant-hazard dams by height vs status of EAPs. (b) Classification by age vs status of EAPs. Based on entries in National Inventory of Dams as of September 28, 2008. Y = Yes, EAP exists; NR = EAP not required; and N = No, EAP does not exist. SOURCE: Modified from Altinakar et al. (2008). Used with permission from the authors, copyright 2012.. Box 3-2 gure 2B Figure 2A in Box 3.2 Bitmapped, Low-res 53

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE Emergency Management Agency (FEMA). It is currently maintained and updated by USACE. Before the September 11, 2001, terrorist attacks on the United States, the NID was freely accessible online and distributed on CD. The NID is still online,5 but informa- tion on hazard classifications, locations of nearest downstream towns, and dam conditions are password protected and not available to nongovernment users. The NID includes information about the location, physical characteristics, dam type, foundation type, designer, owner, and hazard-potential classification of about 84,000 dams. Dams in the database are more than 25 ft high, hold at least 50 acre-ft of water, or are considered to pose a significant hazard if they fail (USACE, 2011a). Dams included in the NID meet the criteria listed in Table 2 of Box 3.1. The hazard-class distribution of all dams in the NID is shown in Figure 3.1. High-hazard dams (at least one death expected in the event of failure) make up almost 17 percent of the inventory. Some 31 percent of the dams in the inventory (those classified as having high or significant hazard potential) are expected to result in economic, environmental, and lifeline losses in the event of failure. Because the states have primary regulatory authority over dams, and because they have different criteria for defining the dams they regulate, the available information on dams that meet the NID criteria varies. Figure 3.2 shows the distribution of dams in the NID. Box 3.3 provides some statistics about the nation’s dams derived from the NID. Since its development, there have been concerns about the accuracy and complete- ness of the NID. Recently, for example, the state of Washington conducted a focused survey to identify nonpermitted dams that should be in the inventory and regulated by the state ( Johnson, 2010).6 The survey identified 28 dams classified as high-hazard dams (including 11 that had safety deficiencies requiring immediate attention) and 11 classified as significant-hazard dams. According to Washington state, high-hazard dams are those whose failure would place three or more homes at risk downstream, and significant-hazard dams one or two homes.7 National Levee Database The NLD is less mature than the NID, having been initiated as a result of the National Levee Database Authority (Public Law 109-148) following Hurricane Katrina. The NLD was constructed and populated under the authority of USACE and made available online to the public on October 27, 2011. To date, it contains information only on USACE levees. Although the National Levee Database Authority calls for inventorying all levees in the country, state and federal funding has not been made available to gather data on nonfederal levees. See nid.usace.army.mil (accessed November 4, 2011). 5 Washington State has jurisdiction over any dam that can impound 10 or more acre-ft of water at the dam crest. 6 See WAC 173-175-130, Engineering Design Reports (available at apps.leg.wa.gov/WAC/default.aspx?cite=173-175-130). 7 54

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Current Dam and Levee Infrastructure, Management, and Governance FIGURE 3.1 Hazard-class distribution of dams in the United States. SOURCE: USACE (2012). Figure 3-1 bitmapped pretty low-res FIGURE 3.2 Distribution of dams cataloged in the National Inventory of Dams. Red dots indicate high-hazard dams; yellow dots indicate significant-hazard dams; and black dots indicate low-hazard Figure 3-2 dams. Hazard classification refers to the consequences of a dam’s failure or misoperation, not to its condi- Bitmapped, tion. SOURCE: USACE (2011a). Low-res 55

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE BOX 3.3 Characteristics of U.S. Dams Based on the National Inventory of Dams About 84,000 dams are described in the National Inventory of Dams. Figures 1 and 2 show the distribution of dams by type (e.g., earth or rock embankments and concrete gravity) and by height, respectively. About half the dams are 25 ft or less in height, and the vast majority are earth embankments. Figure 3 shows the distribution of dam completion dates as listed in the NID. About one-third are older than 50 years, and by the end of this decade, about 56 percent will be older than 50 years. Figure 4 shows the distribution of dam ownership in the United States. Nearly 69 percent of dams are privately owned, and less than 4 percent are owned by the federal government. Federally owned dams, however, include many of the largest dams in the country (e.g., Hoover Dam, Grand Coulee Dam, and Bonneville Dam). Only a small percentage of dams in the United States pose a risk to communities. FIGURE 1 Distribution of dams by type in United States. SOURCE: USACE (2012). Figure 1 in box 3-3 Bitmapped FIGURE 2 Distribution of dams by height in United States. SOURCE: USACE (2012). Figure 2 in box 3-3 Bitmapped 56

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Current Dam and Levee Infrastructure, Management, and Governance FIGURE 3 Distribution of dams by date of completion in United States. SOURCE: USACE (2012). Figure 3 in box 3-3 Bitmapped FIGURE 4 Distribution of dams by ownership in United S tates. SOURCE: USACE (2012). Figure 4 in box 3.3 Bitmapped 57

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE FIGURE 3.3 Distribution of levees by ownership in the United States. SOURCE: NCLS (2009). Figure 3-3 Tens of millions of people reportedly live behind levees (NCLS, 2009). The NLD Bitmapped describes about 14,700 mi (22,500 km) of USACE levees.8 Little is known about the size of the national levee portfolio, especially about levees not under federal jurisdiction. It is estimated that there may be 14,000–16,000 mi (22,500–26,000 km) of levees operated by agencies other than USACE. The National Committee on Levee Safety (NCLS) estimates there may be up to 100,000 mi (161,000 km) of nonfederal levees in the nation (see Figure 3.3). Integration of levee data collected by the FEMA National Flood Insurance Program (NFIP) into the NLD, which is under way, will increase the total number of miles of levee systems in the NLD. More than 21,000 communities currently participate in the NFIP (FEMA, 2011b). An NLD steering committee that comprises USACE and state representatives has been formed, in part, to begin integrating information on nonfederal levees into the NLD. Some states are making their own efforts to inventory levees. In California, for example, the Department of Water Resources has built a levee database of its estimated 9,000 mi (14,500 km) of nonfederal levees since 1997,9 effort on which increased after Hurricane Katrina. The inventory is about 30-40 percent complete; a target date for completion has not been set. USACE is developing guidance and providing assistance to states to improve submission of voluntary information for the NLD. The National Committee on Levee Safety has proposed a levee hazard potential clas- sification system, shown in Table 3.1, similar in overall structure to that for dams (NCLS, 2009). USACE has used this hazard classification system for some of its levees, but See www.usace.army.mil/LeveeSafety/Activities/Pages/act_nldb.aspx (accessed November 1, 2011). 8 S. Ekanayake, CA DWR, personal communication, August 10, 2011. 9 58

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Current Dam and Levee Infrastructure, Management, and Governance TABLE 3.1 Proposed Hazard Potential Classification for Levees Number of Number People Potentially Hazard- of People Inundated Potential Potentially to Depths of Classification Inundated 3 ft or More Additional Considerations High >10,000 >10,000 Includes areas of consequences where critical life-safety infrastructure is at risk (e.g., major hospitals, regional water treatment plants, and major power plants) Significant >1,000 <10,000 Includes areas of consequence where the number of people potentially inundated is low, but there may be significant potential for large economic impacts or losses Low <1,000 0 — NOTE: These classifications use parameters and definitions consistent with those in use by other agencies. For example, California defines an urban area as having 10,000 people and subject to higher flood pro- tection requirements (Senate Bill 5), and FEMA considers shallow flooding to be less than 3 ft (see www. fema.gov/plan/prevent/floodplain/nfipkeywords/sfha.shtm). SOURCE: NCLS (2009). inspection ratings are not included for most levee systems in the NLD. In October 2011, the state government website Governing.com reviewed 744 levee ratings listed in the NLD: 77 percent were found to be rated “minimally acceptable,” indicating minor deficiencies that would not impair levee performance; 12 percent were rated “unacceptable,” indicating they are not expected to provide reliable flood protection; and the remaining 10 percent were rated “acceptable,” indicating they were in satisfactory condition and expected to function (Maciag, 2011). Many of the levees rated as unacceptable may be as much as 70 years old. Frequent inspections are critical for understanding the condition of levees and the risks that they pose. Updating the NLD with new information is important not only for appropriate risk assessment but also because the NLD could influence how priorities for infrastructure funding are set. Levees operated by USACE undergo routine annual inspec- tions and comprehensive inspections every 5 years. The NLD will be updated regularly as levee conditions change. States might not follow the same inspection schedules. DAM AND LEVEE SAFETY PROGRAMS ASDSO distributed a questionnaire to individual state dam safety officials in 2006 to determine what authorities and activities to manage and regulate levee safety existed in the 59

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE spawned a variety of initiatives and technical guidance at different levels of government and in other organizations established to facilitate dam operation and maintenance. In 1979, President Carter signed Executive Order 12148, creating FEMA. Also in 1979, the Ad Hoc Committee on Dam Safety (1979) released the first federal dam safety guidelines for federally owned dams. The guidelines were management oriented, not techni- cal, and remain the basic principles for dam safety. The first formal NDSP was authorized in 1986 as part of the Water Resources Development Act16 and created the NID, a first National Dam Safety Review Board (NDSRB), and provided for assistance to states. In 1996, the National Dam Safety Program Act17 was passed, It placed the NDSP under the director of FEMA and expanded the NDSRB to advise the director. The direc- tor was given no regulatory authority over dam safety but was charged with “encouraging the establishment and maintenance of effective federal and state programs, policies and guidelines”18 National security considerations were added to the legal framework in 2002, and the program was reauthorized again in 2006.19 Since 1996, the Interagency Committee on Dam Safety (ICODS)20 has generated and released a series of guidance documents in an attempt to provide a uniform and consistent dam safety framework for federal, state, and private dam owners and regulators. The guidance, however, is not mandatory. The nation has evolved from total dependence on dam owners to demonstrate “due diligence” with respect to dam safety in the first half of the 20th century, to the development of guidelines and regulations for the safety of federal dams in midcentury, and to guidance to encourage best practices among the states (as owners and regulators) and private owners by the end of the century. In the 21st century, dam safety remains a distributed responsi- bility of many agencies and owners. FEMA has oversight but no regulatory authority for implementing safety. In most cases, nonfederal owners are responsible for safety. Table 3.2 highlights federal agencies that have responsibilities related to the safety of dams they own or regulate in the United States. As already stated, FEMA has oversight of the NDSP and provides guidelines that are the foundation of dam safety policy but has no management or regulatory authority over dam owners or operators. That responsibility is vested in individual federal agencies that construct, own, operate, and regulate dams under laws and policies as discussed above. Dams not expressly the responsibility of a federal agency—the majority in the NID—are regulated by the states. Individual agencies and the states supplement legislation and policies to reflect state management structures and finan- cial responsibilities. See www.fws.gov/policy/361fw1.html. 16 The National Dam Safety Act was passed as part of the Water Resources Development Act of 1996. See epw.senate. 17 gov/dam.pdf. See epw.senate.gov/dam.pdf. 18 See www.fws.gov/policy/361fw1.html. 19 ICODS, established in 1980, is chaired by FEMA to serve as a forum to coordinate federal activities related to dam 20 safety and security. See www.fema.gov/plan/prevent/damfailure/partners.shtm (accessed February 7, 2012). 66

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Current Dam and Levee Infrastructure, Management, and Governance TABLE 3.2 Roles of Federal Agencies in Dam Safety Agency Primary Roles Dams Under Jurisdiction Federal Emergency Lead agency for National Does not own any dams Management Agency Dam Safety Program; chairs National Dam Safety Review Board and Interagency Committee on Dam Safety U.S. Department of Owns or regulates dams; More than one-third of dams in Agriculture (USDA) supports private owners with National Inventory of Dams (NID) are planning, design, finance, and associated with USDA construction Department of Defense Plans, designs, finances, DOD has a total of 267 dams under its (DOD) constructs, owns, operates, jurisdiction on military lands and permits dams; limited to military lands with exception of USACE civil works programs U.S. Army Corps of Plans, designs, constructs, Jurisdiction over USACE dams, dams Engineers operates, and regulates dams; constructed by USACE but operated by permits and inspects dams others, and other flood control dams subject to federal regulation; 631 dams in the NID are associated with USACE Department of the Plans, designs, constructs, About 2,000 dams in the NID under Interior operates, and maintains dams five bureaus Department of Labor Regulates safety- and health- About 1,400 dams under Mine Safety related aspects of miners and Health Administration Federal Energy Issues licenses for, provides 2,530 dams in the NID affecting Regulatory Commission inspections of, and regulates navigable waters nonfederal dams with hydroelectric capability Tennessee Valley Plans, designs, constructs, 49 dams in Tennessee River Valley Authority operates, and maintains dams SOURCE: FEMA (2009). 67

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE Table 3.3 summarizes dam safety governance, guidance, and standards. The principal governance documents are provided in FEMA federal guidelines. Other guidance and standards, mostly technical, come from FERC, USACE, and the Bureau of Reclamation. A single technical specification (e.g., using the probable maximum flood for spillway design) can dominate design considerations. There have been substantial improvements in dam safety practice, but in general, prac- tice fails to take a systems approach in its efforts. For example, the development of the Potential Failure Mode Analysis (PFMA) process (FERC, 2005) requires a deliberate effort to systematically identify and document all potential modes of failure of a dam from all sources. PFMA is used by the Bureau of Reclamation, USACE, FERC, and others in the dam safety community, however, PFMA, as currently applied, lacks a systematic basis for relating the infrastructure-based analyses to the larger river system or to the communities at risk. Thus the utility of PFMA in terms of risk-informed decision making is limited. The PFMA process will likely continue to be used, but the practice could be improved if it evolved to recognize and address epistemic sources of uncertainty, became more detailed to address modes of failure unique to different initiating events (e.g., earthquakes), and was executed using a systems analysis approach in which interactions and interdependencies between system elements are evaluated. Another substantial evolution in guidance provided at the federal level has been the development of a risk assessment framework for dams. It has come about particularly in a collaborative effort between USACE, the Bureau of Reclamation, and FERC. Figure 3.4 outlines the emerging Federal Dam Safety Portfolio Risk Management Process (USACE, 2011b). This process employs the Dam Safety Action Classification (DSAC), a categori- zation scheme ranging from “Urgent and Compelling” to “Normal” for safety-related ac- tions. Interim risk reduction measures (IRRMs) are formulated and undertaken for dams not considered tolerably safe until more permanent remedial measures are implemented. The authority for applying risk has existed for some time (USACE, 2006); it is becom- ing a reality. Application of risk measures will be important in moving from deterministic standards-based approaches to estimating and applying resilience measures that include both the probability and consequence components of risk assessment. Levee Safety LawS and PoLicieS: HiStoricaL Setting, organizationaL roLeS, guidance, and StandardS The principal laws and policies that shape the governance of levee safety in the United States are provided in a simplified chronological list in Appendix C as Table C.2. Just as for laws that define dam safety policy, many laws related to levee safety have been amended multiple times. Because the legal and policy setting for levees is less mature than that for dams, there is less definitive legislation, policy, and technical and management guidance. 68

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Current Dam and Levee Infrastructure, Management, and Governance TABLE 3.3 Dam Safety Governance-Related Guidelines and Standards Responsible Agency Publication Scope Interagency Committee on Dam FEMA 93: Federal Guidelines Federal agency owners; addresses Safety for Dam Safety, (FEMA, management practices; no 2004c; reprinted from 1979) technical standards Federal Emergency Federal guidelines for dam Technical guidelines that augment Management Agency safety: FEMA 93 and create a big-picture framework for state dam safety FEMA 64: Emergency Action programs Planning for Dam Owners (FEMA, 1998) FEMA 333: Hazard Potential Classification System for Dams (FEMA, 2004b) FEMA 65: Earthquake Analysis and Design of Dams (FEMA, 2005) FEMA 94: Selecting and Accommodating Inflow Design Floods for Dams (FEMA, 2004d) FEMA 148: Glossary of Terms ( FEMA, 2004a) Federal Energy Regulatory Chapter 14: Engineering Dam Safety Performance Commission Guidelines updated July 1, Monitoring Program and Potential 2005 (FERC, 2005) Failure Modes Analysis U.S. Army Corps of Engineers ER 1100-2-1156, Safety of New Policy on application of risk Dams—Policy and Procedure and portfolio methods to dam (USACE, 2011b) safety throughout USACE Bureau of Reclamation Dam Safety Risk Analysis Best Summary of best practices in Practices Training Manual spectrum of technical subjects (USBR, 2011a) relevant to dam safety; collaborative with USACE 69

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE Federal Dam Safety Portfolio Risk Management Process U.S. Army Corps of Engineers U.S. Bureau of Reclamation Federal Energy Regulatory Commission DSAC Classification Routine Implement Risk Inspections Management Normal O&M Measures Monitoring Ongoing For All Dam Safety Dams Modification Study Intermediate Additional including Risk Inspections Issues Assessment Periodic DSAC Classification, Inspection and Decision about Tolerable Risk Risks, Update IRRM Assessment Does the Incident or Issue Incident or Inspection Finding Trigger Evaluation Special Yes DSAC Review and IRRM? including Risk Inspection Assessment No FIGURE 3.4 Schematic of emerging Federal Dam Safety Portfolio Risk Management Process. Green boxes represent routine dam safety processes executed under the federal dam safety guidelines (outer loop) or nonroutine safety processes (inner loop). For any process, “yes” indicates further effort and an- Figure 3.5 other decision; “no” indicates return to routine activities. Scrutiny of a potential problem (yellow diamond) triggers a nonroutine process, and a decision made regarding if and what actions are necessary, and if actions taken have been sufficient. DSAC (Dam Safety Action Classification) depicts the degree of urgency of safety-related actions. IRRMs (Interim Risk Reduction Measures) are formulated and undertaken for dams not considered tolerably safe until more permanent remediation measures are implemented. SOURCE: USACE (2011b). 70

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Current Dam and Levee Infrastructure, Management, and Governance Defining legislation is emerging only recently, and is limited to the requirement to create a National Committee on Levee Safety and a proposal for a national levee safety program. Levee safety has been a concern for most of the last century, but other than individual federal-agency programs and state-level initiatives, efforts have been ad hoc. Although intended only to be a requirement for the NFIP,21 the NFIP 100-year flood—rather than hydrograph shape and duration—has become a de facto national standard. The 100-year water elevation now serves as a baseline for many levee applications. The 2005 authorization of the NLD and the 2007 Water Resources Development/ National Levee Safety Act have placed levee safety in phase with where dam safety was in the 1980s.22 These steps constitute an initial legal and policy scaffold from which levee safety can be designed and constructed into a nationally consistent and rigorous effort (given the appropriate attention and resources). It will be crucial to bring diverse com- munity members and stakeholders together to create a uniform structure for management and technical decision making. An important development will be the application of risk assessment.23 The NCLS (2009) has submitted a report and recommendations for policy and organization for a national levee safety program, but its recommendations remain under consideration (as of this writing). The current Economic and Environmental Principles and Guidelines for Water and Related Land Resources Implementation Studies (P&G) are the fundamental policies that govern how federal agencies evaluate proposed water resource development projects, emphasizing national economic benefits as the primary criterion for project justification ( WRC, 1983). The secretary of the Army was tasked with updating the P&G under the Water Resources Development Act (WRDA) of 2007.24 The Obama Administration is expanding the scope of the P&G to include all federal water resources agencies.25 Major responsibilities in levee safety rest with FEMA and USACE and in some cases with the states. FEMA administers the NFIP, through which it defines its responsibilities related to levees, particularly regarding levee accreditation and mapping areas protected by levees. FEMA is examining the impact of levee mapping on the NFIP, initiatives such as the Map Modernization program26 (which, among other things, establishes criteria for levee accreditation), and is examining risk-based approaches. FEMA also cochairs the National Committee on Levee Safety. USACE is responsible for the 14,700 miles of levees it has constructed, operates, and maintains, as well as levees it has constructed but are oper- ated and maintained by others, and levees included in the Rehabilitation and Inspection See a www.fema.gov/business/nfip/. 21 See 140.194.146.135/LeveeSafety/Documents/timeline.pdf. 22 Some states are developing new flood hazard criteria. California, for example, has a draft standard in place for using 23 the 200-year return-period peak flood as its design criterion for urban and urbanizing areas (CA DWR, 2012b). See www.gpo.gov/fdsys/pkg/PLAW-110publ114/content-detail.html. 24 See www.whitehouse.gov/administration/eop/ceq/initiatives/PandG. 25 See www.fema.gov/plan/prevent/fhm/mm_main.shtm (accessed February 8, 2012). 26 71

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE Program (per Public Law 84-99).27 The Secretary of the Army is responsible for carrying out activities of the new National Levee Safety Program Act.28 The USACE Director of Civil Works chairs the NCLS tasked with developing policy and recommendations for a National Levee Safety Program under that act. Their report, delivered in January 2009 remains under review by the Office of Management and Budget and, as of the writing of this report, the recommendations remain unaddressed.29 Other federal agencies, including the Department of Interior (DOI) and U.S. Department of Agriculture, have roles in levee safety. The DOI Bureau of Reclamation manages some levees associated with water supply and flood control projects and oversees levees associated with some irrigation projects that are owned and operated by others. The USDA Natural Resources Conservation Service designs levees to provide protection to support agricultural use of land (ILPRC, 2006). Table 3.4 summarizes guidance and standards for levee safety. As for dam-related guidance, these are technical in nature and support governance by informing decisions. An important technical issue affecting governance is standards related to the extent that hazards affect design and operation. For example, USACE standards for levee design were once based on the Standard Project Flood (SPF), a flood that can be expected from the most severe combination of meteorologic and hydrologic conditions considered reasonably characteristic of the region. The SPF was often considered to be equivalent to a 300-year (or more) return-period event when plotted on an extrapolated flood-frequency curve for the location (USACE, 1965, 2006). With the acceptance of a 100-year peak flood as the standard in accordance with the NFIP, the design criterion was effectively changed (e.g., from a 300-year to a 100-year return period). More recently, USACE has been moving to risk-based design, creating a new design paradigm for the United States (USACE, 2011b). FEMA is considering incorporating risk-based standards into the NFIP; this would con- stitute a major shift in design guidance and standards for levees (see Box 3.6). Given the lack of national policy, guidance, or standards for states, NFIP criteria influ- ence management decisions via local government or community initiatives established to qualify for flood insurance. But as stated earlier, few states keep lists of levees within their borders, and about half the states have no formal authority or program at the state level for levee safety or inspection programs (as of 2006).30 Fewer than one-third of states have even modest safety programs, whose implementation is often delegated to local authorities or programs, and only about 20 percent of the states have relatively comprehensive authori- ties and programs. Management of levees in some states is through levee boards or similar organizations. Levee boards in Louisiana, for example, are managed through the Depart- ment of Transportation and Development and consist of community members appointed See www.saj.usace.army.mil/Divisions/Operations/Branches/EmergencyMgt/programs_RIP.htm. 27 See uscode.house.gov/download/pls/33C46.txt. 28 See www.leveesafety.org/faq_committee.cfm. 29 M. Ogden, ASDSO, personal communication, September 7, 2011. 30 72

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Current Dam and Levee Infrastructure, Management, and Governance TABLE 3.4 Levee-Safety Governance-Related Guidance and Standards Date Responsible Organization Publication October 2010 U.S. Army Corps of Engineers Proceedings of the Workshop, “Exploration of (USACE) Tolerable Risk Guidelines for the USACE Levee Safety Program,” Institute for Water Resources Report 10-R-8 April 2009 USACE ETL 1110-2-571, Guidelines for Landscape Planting and Vegetation Management at Levees, Floodwalls, Embankment Dams, and Appurtenant Structures October 2008 State of California Draft Interim Levee Design Criteria for Urban and Urbanizing Areas (200-year protection by 2015) April 2000 USACE EM 1110-2-1913, Design and Construction of Levees May 2005 USACE ETL 1110-2-569, Design Guidance for Levee Underseepage August 2010 USACE EC 1110-2-6067, USACE Process for the NFIP Levee System Evaluation August 2005 Federal Emergency Procedure Memorandum 34, Interim Management Agency (FEMA) Guidelines for Studies Including Levees. Procedure Memorandum 34 Requires Certification Data on Levees July 2008 FEMA Procedure Procedure Memorandum 43, Guidelines for Memorandum 43 Identifying Provisionally Accredited Levees. Removes levee from NFIP if not accredited and allows provisional accreditation for 2 years October 2002 44 CFR § 65.10 Section 65.10 of National Flood Insurance Program Regulations: FEMA guidance on mapping areas protected by levee systems (not risk based) by the governor. Louisiana has a state association of levee boards, ostensibly to coordinate activities of all Louisiana levee boards.31 Of formal state levee-safety programs, California’s, in its Department of Water Resources, appears to be the most advanced (see Box 3.7). See www.albl.org (accessed February 8, 2012). 31 73

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DAM AND LEVEE SAFETY AND COMMMUNITY RESILIENCE BOX 3.6 Uncertainty in Hazard Characterization The uncertainty in hazard characterization is increasingly recognized in applying risk-based procedures (and setting policy related to their use). Calculations of the frequency of flood events, for example, are im- proved with larger, accurate, and complete historical-event databases. The greater the number and accuracy of events in the database, the smaller the uncertainty in the estimate of the frequency of future events. This can be demonstrated through the calculation of return-period frequency of hurricanes in the Gulf of Mexico. Hurricane return-period calculations have long been based on the atmospheric pressure at the hurricane center (its central pressure). Table 1 illustrates the change in estimated return period for a storm like Katrina, given the size of the historical-event database. The return period of a hurricane with a central pressure and maximum wind speeds similar to those of Hurricane Katrina would have been calculated at 900 years by using the historical database as of 1959, but at only at 98 years on the basis of the historical record as of 2005 (Irish et al., 2008). In addition, the use of central pressure alone, as was previously done, is not ad- equate to characterize the surge generation potential of a hurricane. It is necessary to consider both central pressure (storm intensity) and radius to maximum winds (physical size) of the storm to represent its ability to generate storm surge. Therefore, using the Saffir-Simpson Scale (representing the intensity of sustained winds) as a basis of characterizing return period relevant to surge levels is inadequate. In the 1960s, the levee systems for hurricane protection around New Orleans were designed according to the USACE criteria that, at the time, were thought to accommodate a 200- to 300-year event. The uncer- tainty analysis conducted by IPET (2009) as a component of the risk assessment of the levee and floodwall systems in place during Katrina estimated that the system had a mean failure period of 40–50 years (caused by catastrophic breaching, given the 2005 knowledge base of hurricane hazards in the gulf). TABLE 1 Variability of Return Period of Hurricane Hazard in Gulf of Mexico Publication (Year) and Period of Record Meteorological U.S. Weather Bureau National Weather National Oceanic and Parameter Tech Report 33 (1959) Service Tech Report 23 Atmospheric Administration 1900–1956 (1979) 1900–1975 and National Climatic Data Center Preliminary Analysis (2006) 1900–2005 100-year central 934.6 926.2 901.7 pressure index (millibars) 100-year 1,013.2 1,008.1 1,007.9 peripheral pressure (millibars) Return period for a 900 285 98 storm of Hurricane Katrina intensity (905 mb) (years) SOURCE: IPET, (2007a, 2009). 74

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Current Dam and Levee Infrastructure, Management, and Governance BOX 3.7 Levee Safety in California California has a highly developed levee safety program. The Division of Water Management in the California Department of Water Resources (DWR) was established in 1977 and is divided into five offices responsible for forecasting, integrated environmental stewardship and flood management, design and con- struction of flood control projects, rehabilitation of California system levees, and operation and maintenance of federally constructed flood control structures.a The California FloodSAFE initiative, formulated in 2007, is aimed at more effective floodplain management, risk reduction, and development of a comprehensive, systemwide flood management plan for the Central Valley of California. A major tenet of the FloodSAFE initiative is to require that building codes include flood damage-reduction measures for the estimated 200-year floodplain.b This applies to areas protected by facilities of the Central Valley Flood Protection Plan where flood depths exceed 3 ft for the 200-year flood event (0.5 percent annual chance of flood). Code updates are planned in cycles and include such measures as requiring flood evacua- tion locations to be above the 200-year water-surface elevation, and requiring that flood vents be designed to reduce the potential for structural collapse (by reducing hydrostatic differential on walls).c FloodSAFE also includes preparation of 200-year flood inundation-area maps and flood information for owners and residents. The program is the focal point of the Division of Flood Management in the DWR. Resources in the DWR have been divided into seven “functional areas” as depicted in the figure to prepare for implementation of the program. Limited financial resources will be the major challenge for full implementation of FloodSAFE. Organization and alignment of DWR resources to prepare for the implementation of the DWR FloodSAFE initiative. SOURCE: CA DWR (2012a). See www.water.ca.gov/floodmgmt/ (accessed March 8, 2012). a See www.ca.gov/floodsafe/ (accessed March Box 3-7 new 8, 2012). b See www.water.ca.gov/BuildingCod (accessedBitmapped March 8, 2012). c 75

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