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Levees and the National Flood Insurance Program: Improving Policies and Practices (2013)

Chapter: 2 Treatment of Levees Within the National Flood Insurance Program

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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
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2

Treatment of Levees Within the National Flood Insurance Program

Along with the establishment of the National Flood Insurance Program (NFIP), the passage of the National Flood Insurance Act of 1968 established a requirement for the U.S. Department of Housing and Urban Development (HUD) to “identify and publish information with respect to all floodplain areas, including coastal areas located in the United States, which ha[ve] special flood hazards, within five years following August 1, 1968….”1 This direction led to the establishment within HUD and subsequently within the Federal Emergency Management Agency (FEMA) of programs to map flood-prone areas in communities wishing to participate in the NFIP.

As the NFIP and mapping began, there was no established standard for what constituted a special flood hazard area, although the one and two percent annual chance floodplains had been identified as benchmark levels of flood control in some efforts of the U.S. Army Corps of Engineers (USACE) and the Tennessee Valley Authority in connection with their floodplain management activities. In 1969, HUD asked the University of Chicago to convene a group of experts to recommend what might be a logical definition of the special flood hazard area. The group recommended that the one percent annual chance flood be considered as an initial standard for the NFIP. After some consideration within federal agencies, in 1971, HUD issued a rule establishing the one percent annual chance flood as the minimum standard for the regulation required by the NFIP, that is, the Special Flood Hazard Area (SFHA).

The Federal Insurance Administration (FIA), which had been established as an element of HUD, began mapping the nation’s flood risk through contractors and federal agencies. Flood Hazard Boundary Maps (FHBMs), delineating the SFHA, and Flood Insurance Rate Maps (FIRMs), delineating the SFHA and risk premium zones, were established. Also, land was classified according to flood risk on FIRMs and FHBMs as high-, moderate-, or low-risk zones (Appendix E). The SFHA is considered high-risk, and this land is depicted as either Zone A or V (A, AE, A1-A30, AH, AO, AR, A99, V, VE, and V1-V30). Moderate- to low-risk areas, those outside the SFHA that are still subject to some level of flooding, are depicted as Zones B, C, or X. Those with undetermined flood risk can be classified as Zone D.

The mapping entities encountered existing flood protection works that were considered to have reduced the flood threat to the communities located behind them. Because many of these structures, mostly levees, had, in the past, successfully passed what had been considered a one percent annual chance flood, both local communities and the contractors raised the issue of excluding areas with a one percent annual chance or greater structure from

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1 The National Flood Insurance Act of 1968, §1360, 42 U.S.C. §4101.

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

BOX 2-1
“Without-Levee” Analysis

The practice of not recognizing nonaccredited levee systems on FIRMs, and recognizing areas behind these structures as part of the SFHA, is referred to in this report as FEMA’s “without-levee” analysis. An all-or-nothing approach, it either gives communities credit for a one percent annual chance levee system, exclusion from the SFHA, and exemption from the mandatory purchase requirement or it does not; that is, a levee that is not accredited is not depicted on the FIRM as having any flood reduction impact. A levee system that is not accredited is not considered in flood hazard analyses to determine the reduction of risk behind the levee system, even though some risk reduction at a level below that offered by an accredited levee system might be provided.

the SFHA. Following 1973 congressional hearings that raised similar points, FIA concurred in this approach and authorized the removal of areas behind levees from the SFHA where the levees provided 100-year protection (Richard W. Krimm, personal communication, 2012; Box 2-1). It is not apparent that any regulations or rules were developed to formalize this practice.

Because the focus was on mapping the unprotected areas, little attention was given to the physical status of many of the levees. In many cases, there were no specific inspections or analyses of the levees. Their acceptance was based primarily on having been constructed by the federal government or having previously withstood a significant flood. In a 1974 amendment to the 1968 National Flood Insurance Act, the Congress affirmed the one percent annual chance flood as the minimum standard for the program. The amendment, known as the Brooks Amendment, was made a part of the Housing and Community Development Act of 19742 and also included provisions for allowing certain structures to be accredited if work was under way to achieve recognition.

While the one percent annual chance standard was being used in mapping areas subject to regulation under the Act, discussion continued between HUD and USACE over the appropriateness of the standard. In 1977, USACE indicated to HUD that setting the design of levees in urban areas at the one percent annual chance level could be imprudent because that is not a high degree of protection (IFMRC, 1994). At the same time, senior engineering officials within HUD recommended to FIA management that it strongly consider a federal policy that would recognize only levees designed to provide protection against the standard project flood (SPF)3 (Crompton, 1977). USACE recommended use of a larger design flood such as the SPF for new levees (Wilson, 1978). USACE headquarters also issued guidance to its field elements indicating “on the assumption that exceedance of the design flow would cause a catastrophe, the standard project flood (SPF) is the desirable minimum level of protection that should be recommended for high levees, high floodwalls and high velocity channels in urban areas” (Wilson, 1978).

In 1977, Executive Order 11988 was issued, requiring federal agencies to “avoid to the extent possible the long and short term adverse impacts associated with the occupancy and modification of floodplains and to avoid direct or indirect support of floodplain developments wherever there is a practicable alternative. …” It required each agency to “provide leadership and take action to reduce the risk of flood loss, to minimize the impacts of floods on human safety, health, and welfare, and to restore and preserve the natural and beneficial values served by floodplains in carrying out its responsibilities ….”

In 1979, responsibility for the NFIP was transferred from HUD to the newly established FEMA, and FIA became a part of FEMA. In 1980, the FIA administrator recommended to the FEMA director “consideration of a standard in excess of the 100-year flood, such as the Standard Project Flood, for local protection works to be recognized by FEMA.” The FIA administrator also noted that USACE had recommended this to FIA (Jimenez, 1980). FIA’s concerns were focused on the following:

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2 Public Law 93-383.

3 The SPF is a derived discharge estimate that represents a flood that can be expected from the combination of the most severe meteorologic and hydrologic conditions that are considered reasonably characteristic of a region (USACE, 1965).

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

• “It is estimated that levee overtopping or failure [was] involved in approximately 1/3rd of all flood disasters;

• “The 100-year flood is generally found to be a low design standard for structures protecting densely populated areas;

• “Only a fraction all earthen levees built at the computed hundred year flood elevation can be expected to provide protection to the true 1 percent elevation;4

• “The degree of protection to be expected from a 100 year levee is less than that obtained by elevating individual buildings to hundred year flood elevation;

• “Crediting a levee with protection against the hundred year flood would remove essentially all NFIP floodplain management requirements;

• “Results of USACE nonfederal dam inspections suggest that a large percentage of private or locally built levees as well as dams are or can be expected to be poorly designed and maintained” (NRC, 1982).

FEMA was also concerned that “the use of a 100 year standard was encouraging construction of levees to the 100 year design level for the sole purpose of removing an area from the special flood hazard designation” (Jimenez, 1980).

MOVING AHEAD WITH LEVEES IN THE NFIP

As FEMA worked to integrate levees into the NFIP, the White House, the Congress, and FEMA directed that several studies be conducted to provide insights into the role of levees in the NFIP. Recommendations from these studies are found in Appendix F, and summaries of the most relevant are found in subsequent paragraphs in this chapter.

The 1982 National Research Council Study

As a result of concerns within FEMA and USACE in the late 1970s, FEMA issued an interim levee policy in 1981 and asked the National Research Council (NRC) to examine the levee issue and recommend provisions for a “comprehensive levee policy for use in administering floodplain management, insurance, and risk mapping aspects of the National Flood Insurance Program” (NRC, 1982). In 1982, the NRC committee submitted its report to FEMA. The report contained recommendations covering engineering criteria for levee recognition, levee inspection and evaluation, requirements of levee owners, requirements of local communities, liability of local governments and levee districts, floodplain mapping approaches, and treatment of levees in the insurance aspects of the NFIP.

The NRC report concluded that because the basic objective of the NFIP was to mitigate flood damages and that the basic program prohibits construction below the 100-year level, FEMA should require construction of all new levees to at least the one percent annual chance flood. Existing levees that provided protection against 25-year or larger floods should be recognized for the purposes of reducing insurance rates. However, all levees that are given credit for reducing flood risks should meet standard minimum engineering criteria with respect to geometric parameters, freeboard,5 soils and foundation, interior drainage,6 closure devices, and rights-of-way. Recognizing the residual risk behind levees, the committee recommended that FEMA require, “purchase of flood insurance in all areas where the ground is lower than the unconfined 100 year flood level except where protected by levee built to contain the 500 year flood.”

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4 The accuracy of the one percent annual chance flood elevation on a FIRM is affected by a variety of uncertainties in mapping data, for example, the choice of contour interval for terrain. Thus, the “true” one percent annual chance flood elevation is rarely, if ever, known (NRC, 2007).

5 As defined in 44 CFR §59.1, freeboard is: “a factor of safety usually expressed in feet above a flood level for purposes of floodplain management. Freeboard tends to compensate for the many unknown factors that could contribute to flood heights greater than the height calculated for a selected size flood and floodway conditions, such as wave action, bridge openings, and the hydrological effect of urbanization of the watershed.”

6 The drainage that is required to evacuate rainwater from areas behind levees.

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

The committee also recommended that each levee be individually evaluated, hydrologically and structurally, and that FEMA should inventory all levees previously credited as providing protection from the one percent annual chance flood, set priorities, and schedule communities for restudy to reevaluate the levees.

As a follow-up to the NRC report and other internal actions, in 1983 FEMA initiated a system to maintain an inventory of levees, by community name, that were accredited as providing 100-year protection on NFIP maps. In 1985, FEMA issued regulations prescribing the criteria for levee recognition by the NFIP but did not reevaluate existing levees, alter the required level of protection, or move on other nonengineering recommendations (Galloway et al., 2006). The regulations were codified as Title 44, Section 65.10, of the Code of Federal Regulations (44 CFR §65.10; see Appendix A for the text of this section) and established that to be recognized as removing an area from floodplain regulation and mandatory purchase requirements in the NFIP, a levee must provide protection at the 100-year or higher level plus a specified level of freeboard; must meet engineering design standards similar to those used by the USACE; and must be properly maintained and operated under the control of a government entity. The regulations also require that a professional engineer certify the data submitted to support a given levee system’s compliance with the structural requirements set forth in the regulation and must submit certified as-built plans of the levee. Where appropriate, a federal agency with responsibility for levee design may certify that the levee has been adequately designed and constructed to provide protection against the base flood. No provisions were made to reduce the rates for those behind levees providing less than one percent annual chance flood protection or to conduct periodic inspections, and 44 CFR §65.10 has remained unchanged since 1985.

Interagency Floodplain Management Review Committee

From April to October of 1993, the Mississippi and Missouri rivers and their tributaries inundated the surrounding floodplain, causing one of the costliest and most devastating floods in U.S. history. The flood of 1993 brought new attention to the condition of levees both within and outside of the NFIP. In 1994, a White House—based committee studying the 1993 flood reported that activities in floodplains of the United States, even with levee protection, remain at risk, finding that during the Mississippi-Missouri river floods:

• Many locally constructed levees breached and/or overtopped. Frequently, these events resulted in considerable damage to the land behind the levees through scour and deposition [of material from the river channel and the levee itself];

• Levees can cause problems in some critical reaches by backing water up on other levees or lowlands;

• The current flood damage reduction system in the upper Mississippi River Basin represents a loose aggregation of Federal, local, and individual levees and reservoirs;

• Many levees are poorly sited and [as a result] will fail again in the future. (IFMRC, 1994)

The White House study committee also indicated that the SPF flood should be the target flood for population centers and critical facilities protected by levees and that the government should require those behind levees who provide protection against less than the SPF discharge to purchase actuarially based insurance. It also found that federal agencies should ensure proper siting, construction, and maintenance of nonfederal levees. No action was taken by either Congress or the administration on these recommendations.

MAP MODERINIZATION AND LEVEE DECERTIFICATION

As a result of pressure from communities and professional organizations to improve the quality of flood mapping, the President proposed and the Congress, in 2003, authorized FEMA to undertake a 5-year billion-dollar program to modernize its maps by converting existing paper maps to a digital format and in the process, and where possible, provide new engineering analysis. As work began in 2004 on map modernization or “Map Mod,” FEMA representatives became concerned that many of the levees encountered in the mapping process might not, under review, meet the standards of 44 CFR §65.10 and, as a result formed a committee to examine the issue. In April 2005, a small internal Interim Levee Coordination Committee reported that treatment of levees in Map Mod across FEMA regions was inconsistent and that guidance should be issued immediately to ensure that appropriate

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

information about levees was obtained and considered in the map modernization process. It also recommended that a levee coordination committee be established to address this issue (FEMA, 2005).

On August 22, 2005, a week before Hurricane Katrina (Box 2-2), FEMA issued Procedure Memorandum 34, Interim Guidance for Studies Including Levees, which established that as Map Mod was implemented, currently credited levees should be checked against the 44 CFR §65.10 criteria (see Appendix G). When combined with a requirement to review “grandfathered” levees, this action sought to ensure that the accreditation status for all levees in the program was validated. The memorandum further indicated that when the levee owner was not able to produce data or was unable to otherwise substantiate that the levee met criteria, the area protected by the levee would be mapped as being in the floodplain and the requirements for mandatory purchase of insurance and regulation would go into effect when the revised map became effective.

In 2005, the Interagency Levee Policy Review Committee was established by FEMA to develop further guidance on treatment of levees in the NFIP. Membership on the committee included representatives of 10 federal agencies.7 The committee reported in 2006 that:

• Many levees shown on current NFIP maps as providing protection from the 100-year flood have never been evaluated against the criteria of 44 CFR 65.10 …. For levees that are found not to meet 44 CFR 65.10, the areas behind the levees will be identified as SFHAs. The impacts on the community of such an action will be significant.

• The protection afforded by many certified levees decays over time due to various factors, such as changed hydrology or channel characteristics, erosion or deterioration of the embankment due to rodents or tree growth, general lack of proper maintenance, subsidence, or partial levee failures. However, there is no mechanism in place to regularly verify continuing accreditation of levees against 44 CFR 65.10. …

• FEMA does not certify levees, but rather relies on certification provided by Federal agencies or State, local, or other parties seeking accreditation on NFIP maps…. Frequently, communities do not have the requisite resources or technical expertise to properly evaluate the levees against the 44 CFR 65.10 requirements and will have to hire engineering firms to do this work….

• As Procedure Memorandum 34 is implemented, many levees ultimately will not meet the criteria of 44 CFR 65.10 and will have to be shown as “failed” on FIRMs. The performance of detailed levee failure analysis as required by … Guidelines and Specifications will be costly, particularly for countywide [digital flood insurance rate map (DFIRM)] conversion projects and in counties and communities with large numbers of levees….

• The regulatory requirements of 44 CFR 65.10 lack adequate specificity for minimum operation and maintenance standards….

• Risks in areas behind certified levees are not adequately communicated to map users….

• Current requirements treat levees in a binary manner—either they meet 44 CFR 65.10 or they do not. Therefore, residual risk is greatly under-represented, and differences in risk that may exist to those behind certified levees are disregarded. In addition, no distinction between graceful versus chaotic capacity exceedance exists in the way levees are mapped, and there is no identification of the most highly hazardous areas immediately behind/along levees in the event of levee failure. (ILPRC, 2009, pp. 22-23)

The Interagency Levee Policy Review Committee urged FEMA and, as appropriate, other federal agencies to take the following actions immediately:

• When communities are not immediately able to document whether currently certified levees can be recertified and the levees are not known to be at risk, FEMA should notify the communities of the need for a more detailed examination of the levees and provide a specific schedule for that activity. FEMA should require these communities to notify all people in areas behind the levees of the reexamination and identify for them the residual risks and the lack of information about the levees.

• FEMA should define, as a matter of policy, a new flood insurance zone (Zone XL) for areas behind levees that meet the requirements for inclusion in the NFIP. Zone XL would include those areas behind the levee that would be subject to inundation by the 100-year flood if there were no levee. The area between the 100-year and 500-year lines should be shown as a shaded Zone X.

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7 Representatives from six nongovernmental organizations and four states observed committee meetings.

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
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BOX 2-2
Hurricane Katrina

Hurricane Katrina was one of the deadliest and costliest hurricanes in U.S. history. Forming over the Bahamas, Katrina crossed Florida as a Category 1 storm and strengthened in the Gulf of Mexico. It made landfall in southeastern Louisiana on August 29, 2005, impacting Louisiana as well as Mississippi, Alabama, Georgia, and the Florida panhandle to various degrees. The hurricane’s storm surge that pushed ashore from the Gulf of Mexico was over 29 feet, the highest ever recorded in the United States. In total, over 1,700 people were killed and hundreds of thousands were displaced (New York Times, 2012).

The levee system protecting New Orleans, Louisiana, built by USACE and operated and maintained by the local levee districts, failed in the aftermath of Katrina, and a significant portion of the city and surrounding areas were flooded (Figure 2-1). The NFIP experienced an unprecedented number of claims, 212,235, in the 2005 calendar year and over $17 billion dollars in loss dollars paid.a The levee failure cast a spotlight on USACE, prompting litigation, congressional investigation, and a variety of investigations regarding the levee failure.

The impacts of Katrina have been long-lasting economically, environmentally, and from the perspective of human and societal welfare of the city and surrounding area. Levee-related policy was reformed; for example, the National Levee Safety Program Act (2007), which directs USACE to carry out activities to enhance the safety of U.S. levees, was amended, and the USACE Levee Design Manual (USACE, 2000) was revised to incorporate risk-based concepts into levee design.

image

FIGURE 2-1 Aerial photograph of flooding as a result of breached levees in New Orleans in the wake of Hurricane Katrina.

aSee http://www.fema.gov/policy-claim-statistics-flood-insurance/policyclaim-statistics-flood-insurance/policy-claim-13-17.

SOURCE: Taken by Marty Bahamonde on August 29, 2005, available online at http://www.fema.gov/photolibrary/photoCollectionView.do?id=81, accessed December 6, 2012.

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

• FEMA should initiate the revision of 44 CFR 65.10 and other appropriate FEMA guidance and specification documents, to address the technical changes recommended [in] this report.

• As a matter of policy, FEMA should require levee sponsors to conduct annual inspections of their levee systems; biennially submit to FEMA the results of the annual inspections, levee system operation and maintenance records, and an assessment of the levee systems during any flood events that occurred within the reporting period; and every 10 years submit a report that recertifies the engineering and geotechnical conditions of the levee system.

• FEMA and USACE, recognizing the important State and local roles, should develop incentives and support mechanisms to ensure that State and local agencies effectively carry out their responsibilities with respect to levee operation and maintenance.

• FEMA should exclude embankments, such as roads and railroads, from the accreditation of new levee systems unless those embankments are engineered specifically to provide damage/risk reduction from flooding and meet the engineering criteria required of levees. (ILPRC, 2006, pp. 61-62)

The Interagency Levee Policy Review Committee, recognizing the need for additional study and regulation development, urged FEMA to initiate action on the following longer term recommendations:

• … [R]evise 44 CFR 65.10 to phase out, over the next 10 years, the freeboard-based approach and to substitute the risk analysis methodology, with a 90-percent assurance of passing the 100-year flood, to determine the required levee heights….

• … [T]ake immediate steps to examine the feasibility of not recognizing, for NFIP purposes, levees that protect highly urbanized areas unless they provide protection from events greater than 100-year floods (e.g., 500-year floods).

• … [A]ddress the challenge of the residual risk to structures behind levees by seeking legislative change to require property owners to purchase some level of flood insurance for structures behind levees (in the new Zone XL).

• FEMA, working closely with other Federal agencies, States, and communities, should examine how best to deal with climate change, sea-level rise, linked levee systems, and future development as major drivers of future conditions [hydraulics and hydrology (H&H)], with a goal of determining a BFE based on possible, but not fully quantifiable, future conditions.

• FEMA, in coordination with other Federal agencies, States, and communities, should initiate studies to determine how levees could be identified under a scientifically based levee risk-classification system (e.g., high, medium, or low). This system would be based on factors that include the potential depth of flooding in the event of failure or overtopping; the type and density of development in protected areas behind the levee; steps taken to ensure that levee failure does not occur when the levee capacity is exceeded (overtopping); warning times; and the number and types of egress so that people who may be inundated may move out of harm’s way. This levee risk classification would be designated on the FIRM and published in the FIS report. (ILPRC, 2006, p. 62)

(For additional information regarding the advice of the Interagency Levee Policy Review Committee, see Appendix F.) In 2009, FEMA completed the initial Map Modernization Program, digitizing FIRMs covering areas containing 92 percent of the U.S. population (NRC, 2009).

Report of the National Committee on Levee Safety

Title IX of the 2007 Water Resources Development Act (Public Law 110-114), the National Levee Safety Act, directed the establishment of a federal, state/tribal, local/regional, and private-sector committee on levee safety to “develop recommendations for a national levee safety program, including a strategic plan for implementation of the program.” In January, 2009, the committee submitted its report to the Administration (NCLS, 2009).

The report provided a framework for developing a long-term approach to levee safety management, recommending establishment of a National Levee Safety Commission. It also recommended the development of a levee hazard potential classification system, tolerable risk guidelines,8 and national levee safety standards; peer review

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8 Tolerable risk guidelines “categorize the nature of risks in ways that can assist in assessing their acceptability or non-acceptability, and in prioritizing actions for reducing risks” (USACE, 2010).

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

of the FEMA levee certification process; development of a national levee risk communication campaign; establishment of a national levee rehabilitation, improvement, and flood mitigation fund; delegation of levee safety responsibilities to the states; and mandating purchase of risk-based flood insurance in leveed areas. Other recommendations can be found in Appendix F.

LEVEE DEACCREDITATION

Issuance of Procedure Memorandum 34 (FEMA, 2005) and the potential of many levees under study at the time no longer being accredited caused a strong pushback from levee owners and affected communities. Recognizing the need to give those responsible for providing certification information the opportunity to gather that information, in September 2006, FEMA issued Procedure Memorandum 43, Guidelines for Identifying for Provisionally Accredited Levees (PAL), which provided a 2-year period for affected levee owners to complete those actions necessary to retain their accreditation (Appendix G). The Memorandum, which was reissued the following March, provides more detailed guidelines that allow

mapping partners to issue preliminary and effective versions of DFIRMs while the levee owners or communities are compiling the full documentation required to show compliance with 44 CFR Section 65.10…. If the levee qualifies for the PAL designation, FEMA will provide the community 90 days to sign and return an agreement indicating that the full documentation for 44 CFR Section 65.10 will be provided within 24 months of the signed agreement.

The Memorandum also provided guidelines for levees whose maintenance was deficient, allowing time for these deficiencies to be remediated (FEMA, 2006).

In April 2009, FEMA issued Procedure Memorandum 53, Guidance for Notification and Mapping of Expiring Provisionally Accredited Levee Designations (see Appendix G). This Memorandum provided instructions to FEMA field units concerning the steps that were to be taken if PAL-designated levees had not completed the required activity within the 24-month period. In these cases, the mapping partners were instructed to map the area as being within the SFHA or as “without levee,” thus removing areas previously exempted from compliance with mandatory insurance and regulatory actions from this status (FEMA, 2009).

Affected communities, faced with the potential movement of the previously exempt areas into the floodplain and the necessity to purchase flood insurance at rates that might be the same as those without any protection argued that some credit physically and fiscally should be given to the presence of the deficient levees in any analysis of without-levee conditions. In February 2011, 27 U.S. senators sent a letter to FEMA, urging the Administrator:

“to use your current authorities to discontinue the Federal Emergency Management Agency’s (FEMA) use of “without levees” analysis to determine new Flood Insurance Rate Maps (FIRMs) in cases where a final determination has not been made and an affected community objects to such analysis in favor of more precise methods of flood modeling. “Without levee” modeling methods assume that a levee or flood control structure that exists in physical reality does not exist for the purposes of modeling, reducing the precision or flood maps and eroding public confidence in the mapping process itself.” (U.S. Senate, 2011)

At the same time, 49 members of the U.S. House of Representatives sent a similar letter to Administrator Fugate.

In response, FEMA Administrator Fugate directed FEMA staff to replace the without-levee modeling approach with a suite of methodologies that would be technically sound, credible, and cost-effective, and would better meet the needs of citizens while providing more precise results that better reflect the impact of levees on flood risk. This procedure would not replace the need for levee owners or the associated communities to remain engaged in flood risk management activities or change the existing requirements for them to provide levee certification information as outlined in 44 CFR §65.10 (Fugate, 2011a). The development and current status of this new approach, the Levee Analysis and Mapping Procedure, is discussed in Chapter 4.

In June 2011, testifying before the U.S. Senate Committee on Banking, Housing, and Urban Affairs, FEMA Administrator Fugate pointed out that

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

while FEMA is committed to working closely with communities to develop the most accurate flood maps possible, the current “in or out” nature of the SFHAs (one is either in an SFHA or not) has left the program with a perceived credibility problem, as there is no gradation of risk identified within a flood zone. (Fugate, 2011b)

The Biggert-Waters Flood Insurance Reform and Modernization Act

The Biggert-Waters Flood Insurance Reform and Modernization Act of 2012 (heretofore known as the Biggert-Waters Act) was signed into law on June 29, 2012, extending the NFIP until September 30, 2017.9 Reforms and modernization directives in the Biggert-Waters Act call for a variety of changes that apply to the NFIP, many of which are relevant to this report. These changes are discussed throughout the chapters, when relevant, and summarized here.

Section 100207 of the Biggert-Waters Act directs full, risk-based premiums or a “premium adjustment to reflect the current risk of flood” in area participating in the NFIP:

any property located in an area that is participating in the national flood insurance program shall have the risk premium rate charged for flood insurance on such property adjusted to accurately reflect the current risk of flood to such property, subject to any other provision of this Act. Any increase in the risk premium rate charged for flood insurance on any property that is covered by a flood insurance policy on the effective date of such an update that is a result of such updating shall be phased in over a 5-year period, at the rate of 20 percent for each year following such effective date.

Related to this report, the FEMA administrator is also directed to contract with the National Academy of Sciences to study exploring methods for understanding graduated risk behind levees and the associated land development, insurance, and risk communication dimensions.10

The FEMA administrator is required to form a Technical Mapping Advisory Council to deal with map modernization issues.11 This includes recommendations on how to “ensure that flood insurance rate maps incorporate the best available climate science to assess flood risks” and that the impact of sea level rise is considered. The Biggert-Waters Act directs FEMA to review, update, and maintain NFIP rate maps with respect to

(i)   all populated areas and areas of possible population growth located within the 100-year floodplain;

(ii)  all populated areas and areas of possible population growth located within the 500-year floodplain;

(iii) areas of residual risk, including areas that are protected by levees, dams, and other flood control structures;

(iv) areas that could be inundated as a result of the failure of a levee, dam, or other flood control structure; and

(v)  the level of protection provided by flood control structures.12

The Biggert-Waters Act also requires FEMA to use the most accurate topography and elevation data available and “any relevant information … relating to the best available science regarding future changes in sea levels, precipitation, and intensity of hurricanes” and coastal inundation, land subsidence and coastal erosion when updating maps.13

Several requirements in the Biggert-Waters Act call for changes that adjust or study fiscal practices of the program. For example, the Act calls for phasing out both subsidies and grandfathering for some properties,14 establishment of a reserve fund,15 requiring the FEMA administrator to develop a plan for repaying the debt

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9 Moving Ahead for Progress in the 21st Century Act, H.R. 4348, Title II, Subtitle A, Flood Insurance Reform and Modernization, 112th Cong. (2012).

10 Section 100231.

11 Section 100215.

12 Section 100216(b)(1)(A).

13 Section 100216(b)(3).

14 For example, subsidies for nonprimary residences, severe repetitive loss properties, and businesses.

15 Section 100212.

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

largely incurred by Hurricane Katrina,16 assess opportunities associated with privatization and reinsurance,17 and imposition of minimum deductibles.18

The Biggert-Waters Act directs the study of the impact, effectiveness, and feasibility of amending the NFIP to include building codes as part of floodplain management criteria developed under NFIP.19

The administrator is called to contract with the National Academy of Sciences to study full-risk—based premiums and means-tested federal assistance in comparison with the current system of flood insurance rates and federally funded disaster relief:

shall conduct … an economic analysis of the costs and benefits to the Federal Government of a flood insurance program with full risk-based premiums, combined with means-tested Federal assistance to aid individuals who cannot afford coverage, through an insurance voucher program. The analysis shall compare the costs of a program of risk-based rates and means-tested assistance to the current system of subsidized flood insurance rates and federally funded disaster relief for people without coverage.20

With respect to levee communication, the Biggert-Waters Act directs the administrator to enhance communication efforts. This includes outreach to states and local communities about map changes and associated insurance rate changes and education of property owners about continued flood risk even when no longer subject to the mandatory purchase requirement.21 Interagency collaboration is also promoted. The Biggert-Waters Act directs the FEMA administrator and the secretary of the Army, acting through the chief of engineers, in cooperation with the National Committee on Levee Safety, to establish a Flood Protection Structure Accreditation Task Force to develop a process to better align the information and data collected by or for USACE’s Inspection of Completed Works (ICW) Program with the flood protection structure accreditation requirements so that information and data collected for either purpose can be used interchangeably and information and data collected by or for USACE under the ICW Program are sufficient to satisfy the FEMA flood protection structure accreditation requirements.22

The Past and Present

Over the past 40 years, the treatment of levees within the NFIP has been a continuous topic of discussion and often, of controversy. Many studies have examined what should be done to ensure that when levees are brought into the NFIP, their presence does not increase the risk faced by those who are located behind them. For fiscal, administrative, and political reasons, few of the recommendations from these studies have been fully adopted. The chapters that follow examine once again many of these recommendations, and offer new recommendations in the interest of improving the NFIP and floodplain management in the United States.

REFERENCES

Crompton, F. M. 1977. Memorandum to Richard Krimm on HUD Policy on Levees, Engineering Division Recommendations. Washington, DC: HUD.

FEMA (Federal Emergency Management Agency). 2005. Interim Guidance for Studies Including Levees. Procedure Memorandum 34. Washington, DC: FEMA.

FEMA. 2006. Guidelines for Identifying Provisionally Accredited Levees. Procedure Memorandum 43. Washington, DC: FEMA.

FEMA. 2009. Guidance for Notification and Mapping of Expiring Provisionally Accredited Levee Designations. Procedure Memorandum No. 53. Washington, DC: FEMA.

_______________

16 Section 100213.

17 Section 100232.

18 Section 100201.

19 Section 100235.

20 Section 100236(b).

21 Section 100243.

22 Section 100226.

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

Fugate, C. 2011a. Letter to Senator Thad Cochran regarding discontinuation of without-levees analysis. Washington, DC: FEMA. Available online at http://www.pnwa.net/new/Articles/Fugate%20response%20to%20Senator%20Cochran.pdf. Accessed March 7, 2013.

Fugate, C. 2011b. Testimony on the National Flood Insurance Program Reform, June 9, Before the Senate Committee on Banking, Housing, and Urban Affairs. Available online at http://www.banking.senate.gov/public/index.cfm?FuseAction=Files.View&FileStore_id=c6f08bf5-5daa-4406-b461-1781159ec9c1.

Galloway, G. E., G. B. Baecher, D. Plasencia, K. G. Coulton, J. Louthain, M. Bagha, and A. R. Levy. 2006. Assessing the Adequacy of the National Flood Insurance Program’s 1 Percent Flood Standard. Washington, DC: American Institutes for Research. Available online at http://www.fema.gov/library/viewRecord.do?id=2595.

IFMRC (Interagency Floodplain Management Review Committee). 1994. Sharing the Challenge: Floodplain Management into the 21st Century. Washington, DC: IFMRC.

ILPRC (Interagency Levee Policy Review Committee). 2006. The National Levee Challenge: Levees and the FEMA Flood Map Modernization Initiative. Available online at http://www.fema.gov/library/viewRecord.do?id=2677. Accessed August 8, 2012.

Jimenez, G. M. 1980. Memorandum to John W. Macy, Director of FEMA; Subject: Levees, February 1. Washington, DC: Federal Insurance Administration.

NCLS (National Committee on Levee Safety). 2009. Recommendations for a National Levee Safety Program. Washington, DC: NCLS.

NRC (National Research Council). 1982. A Levee Policy for the National Flood Insurance Program. Washington, DC: National Academy Press.

NRC. 2007. Elevation Data for Floodplain Mapping. Washington, DC: The National Academies Press.

NRC. 2009. Mapping the Zone: Improving Flood Map Accuracy. Washington, DC: The National Academies Press.

New York Times. 2012. Hurricane Katrina. Available online at http://topics.nytimes.com/top/reference/timestopics/subjects/h/hurricane_katrina/index.html. Accessed December 10, 2012.

USACE (U.S. Army Corps of Engineers). 1965. Standard Project Flood Determinations, EM 110-2-14-11. Washington, DC: USACE.

USACE. 2000. Design and Construction of Levees. EM 1110-2-1913. Washington, DC: USACE.

USACE. 2010. Proceedings of the Workshop Exploration of Tolerable Risk Guidelines for the USACE Levee Safety Program. Institute for Water Resources Report 10-R-9. Washington, DC: USACE.

U.S. Senate. 2011. Letter to Administrator Fugate. Available online at http://www.fema.gov/library/viewRecord.do?id=4984. Accessed March 15, 2013.

Wilson, D. 1978. Letter to Richard Krimm. Washington, DC: U.S. Army Corps of Engineers.

Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×

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×
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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
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Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
Page 29
Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
Page 30
Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
Page 31
Suggested Citation:"2 Treatment of Levees Within the National Flood Insurance Program." National Research Council. 2013. Levees and the National Flood Insurance Program: Improving Policies and Practices. Washington, DC: The National Academies Press. doi: 10.17226/18309.
×
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The Federal Emergency Management Agency's (FEMA) Federal Insurance and Mitigation Administration (FIMA) manages the National Flood Insurance Program (NFIP), which is a cornerstone in the U.S. strategy to assist communities to prepare for, mitigate against, and recover from flood disasters. The NFIP was established by Congress with passage of the National Flood Insurance Act in 1968, to help reduce future flood damages through NFIP community floodplain regulation that would control development in flood hazard areas, provide insurance for a premium to property owners, and reduce federal expenditures for disaster assistance. The flood insurance is available only to owners of insurable property located in communities that participate in the NFIP. Currently, the program has 5,555,915 million policies in 21,881 communities3 across the United States.

The NFIP defines the one percent annual chance flood (100-year or base flood) floodplain as a Special Flood Hazard Area (SFHA). The SFHA is delineated on FEMA's Flood Insurance Rate Maps (FIRM's) using topographic, meteorologic, hydrologic, and hydraulic information. Property owners with a federally back mortgage within the SFHAs are required to purchase and retain flood insurance, called the mandatory flood insurance purchase requirement (MPR). Levees and floodwalls, hereafter referred to as levees, have been part of flood management in the United States since the late 1700's because they are relatively easy to build and a reasonable infrastructure investment. A levee is a man-made structure, usually an earthen embankment, designed and constructed in accordance with sound engineering practices to contain, control, or divert the flow of water so as to provide protection from temporary flooding. A levee system is a flood protection system which consists of a levee, or levees, and associated structures, such as closure and drainage devices, which are constructed and operated in accordance with sound engineering practices.

Recognizing the need for improving the NFIP's treatment of levees, FEMA officials approached the National Research Council's (NRC) Water Science and Technology Board (WSTB) and requested this study. The NRC responded by forming the ad hoc Committee on Levee and the National Flood Insurance Program: Improving Policies and Practices, charged to examine current FEMA treatment of levees within the NFIP and provide advice on how those levee-elated policies and activities could be improved. The study addressed four broad areas, risk analysis, flood insurance, risk reduction, and risk communication, regarding how levees are considered in the NFIP. Specific issues within these areas include current risk analysis and mapping procedures behind accredited and non-accredited levees, flood insurance pricing and the mandatory flood insurance purchase requirement, mitigation options to reduce risk for communities with levees, flood risk communication efforts, and the concept of shared responsibility. The principal conclusions and recommendations are highlighted in this report.

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