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3 Management and Approaches INT1lODUCTION Any attempt to formulate national policies to address coastal ero- sion hazards confronts a task of substantial complexity. This chapter reviews some of the elements that contribute to this complexity: . political); types of diversity (e.g., physical, settlement morphology, and types of private and public participants in coastal manage- ment, . methods available for erosion hazard reduction (engineered projects) and building and land use management; and ~ institutional variation of federal approaches to coastal man- agement. TYPES OF DIVERSITY Federal resource management programs inevitably confront the dilerru~na of how to reconcile the need for uniform national policy objectives with regional diversity of geographic conditions. This issue arises, for instance, with respect to air and water quality standards, ocean dumping and disposal of dredged spoils, wetland regulations, and floodplain management. The nation's coastlines are diverse in 44

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MANAGEMENT AND APPROACHES 45 several respects: physical, settlement, and political. Each of these classes of diversity is reviewed briefly below. Physical Diversity Coastal shorelines differ markedly in physical characteristics and in vulnerability to erosion, as discussed in Chapter 2. Principal types of shorelines and examples of their locations include: crystalline bedrock (e.g., central and northern Maine); eroding bluff (e.g., outer Cape Cod, Great Lakes); pocket beach (e.g., southern New England, California, Ore- gon); strandplain beach (e.g., Myrtle Beach, South Carolina, and Holly Beach, Louisiana); barrier beach (e.g., New York and Texas); coral reef and mangrove (e.g., South Florida); and coastal wetland (e.g., Louisiana). Erosion hazards can affect each of the above except for bedrock shorelines. Erosion, as compared to accretion or stability, and its rate over time at a given point along the shoreline depend on factors such as (1) direction of littoral drift, (2) inlet dynamics, (3) sand supply, (4) short- and long-term climate fluctuations, (5) gradient of submerged ocean or lake bottom, (6) relative mean sea level, and (7) human actions affecting shoreline processes (see Table 2-1~. Settlement Diversity Shorelines differ dramatically in their human settlement char- acteristics. Extensive areas of the nation's coastlines essentially are undisturbed, and much of the shore remains in a relatively undis- turbed condition (e.g., national seashores, national forests, parks, wildlife refuges, military bases and recreation areas, state and local parks, and nature preserves owned by the Nature Conservancy and comparable organizations). Shorelines within such facilities gener- ally are uninhabited except for private inholdings, which are com- mon in several of the major national seashores (e.g., Cape Cod, Massachusetts; Fire Island, New York; Assateague Island, Virginia and Maryland; and Cape Hatteras, North Carolina) and national lakeshores (Indiana Dunes and Sleeping Bear Dunes). Substantial areas of shoreline remain in private hands but undisturbed because

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46 MANAGING COASTAL EROSION of lack of access, distance to population centers, physical unsuitabil- ity for development, or personal preference of the owner. At the other extreme, shorelines may be developed extensively with port facilities or lined with commercial, industrial, or high- density residential and resort buildings. Such urbanized shorelines often are hardened by protective riprap, seawalis, or other engineered structures, which may substantially reduce or eliminate the threat of erosion to the protected area. Efforts to protect certain segments of shoreline, however, can in some circumstances induce increased erosion on nearby unprotected shorelines. For instance, groins or jetties can deprive downdrift areas of natural sand supply. On the other hand, groin fields filled by beach nourishment have been successful. Between the two extremes of undeveloped and highly urban- ized shorelines, coastal settlement types vary widely. In the past, settlements on the shorelines were categorized into four types: (1) village, (2) urban, (3) summer, and (4) empty places (Burton et al., 1968~. Today, these classifications are blurred as former summer colonies become winterized for year-round use, high-rise condomini- ums replace the "village" atmosphere of former small communities like Ocean City, Maryland, and major development corporations re- shape the coastal landscape an at Hilton Head, South Carolina, or Amelia Island, Florida (Platt et al., 1987~. During the 1970s and 1980s, many former low-density resort communities experienced rapid structural and demographic growth. This growth was accompanied by the development of infrastructure in the form of sewer lines, water lines, access routes, and beach protection and nourishment projects, largely subsidized by the federal government. Furthermore, the availability of federal flood insurance has been identified as at least a marginal incentive to further coastal development (U.S. General Accounting Office, 19823. Political Diversity The nation's shorelines also show a diversity in the nature and form of political jurisdictions. Nonfederal units of public and quasi- public authority operating in coastal areas include private home- owners' associations, incorporated municipalities, special districts, counties, and states. Of course, all U.S. shorelines are subject to state jurisdiction, but the nature of that role differs considerably from one state to another. Furthermore, most regions of the nation

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MANAGEMENT AND APPROACHES 47 differ In terms of substate political authority. The coast of New Eng- land, for instance, is occupied entirely by incorporated towns and cities. The unknot civil divisions of New York State include incor- porated villages, towns, cities, and counties. New Jersey has all of those as well as boroughs. Local government functions in Maryland and Virginia are largely provided at the county level, except for self- governing cities such as Baltunore and Virginia Beach. Elsewhere, privately owned shorelines may be subject to municipal or county jurisdiction, depending on whether or not the location in question is within an incorporated municipal unit. Furthermore, in the case of coastal barriers, local political units may be self-governing (i.e., lim- ited to the barrier itself) or appendant (i.e., part of a larger mainland jurisdiction). The efficacy of coastal management is related in part to the political geography of minor civil divisions of particular shorelines. Many local units tend to ignore external effects on their neighbors in their choice of approach to the management of coastal erosion (Platt et al., 1987~. These three kinds of diversityphysical, settlement, and politi- cal serve to complicate the shaping of national policy on coastal erosion management. They suggest that no single approach is am propriate or inappropriate everywhere. Public planners and decision makers should avoid basing policies on stereotypes or preconcep- tions as to "typical" shorelines and their state of development and governance. There is precedent for the administration of a national policy that is geographically selective. For example, the Coastal Barrier Resources Act (CBRA) of 1982 (discussed later In this chapter) prohibits further federal flood insurance coverage and other federal incentives to development for undeveloped and unprotected coastal barriers. This act is selective In its coverage, according to the physical character of the shoreline (coastal barrier), settlement type (undevel- oped), and legal status (nonpublic and protected). The CBRA thus is one way to conduct selective implementation of federal policies designed to mitigate future losses caused by coastal erosion. PRIVATE AND PUBLIC PARTICIPANTS IN COASTAL MANAGEMENT The use of coastal land involves diverse private and public de- cision makers and other participants. The exact mix of parties and

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48 MANAGING COASTAL EROSION their respective roles and influence over the development of coastal property vary from one location to another. The types of diver- sity discussed in the preceding section physical, settlement, and political are major factors in determining the interested parties for any given location and development situation. Management of coastal erosion and flood hazards must recognize the variation in the interests and the varied roles of relevant parties. Priorate Sector Among private sector parties ment and use are . i: coastal property owners, developers and builders, evolved in coastal land develop- o homeowner associations, . neighbors or other residents affected by the use of a particular site, lenders, and . realtors. Private property owners are vested with substantial but not exclusive authority to determine the use of their land. Riparian rights traditionally entitle the waterfront land owner to embark upon the water; but the state, sometimes in conflict with those rights, is custodian of a public trust to control the use of the water and the land under it for the benefit of all. Property owners are typically the initiators of land use change (e.g., from an open to a developed condition or from one development form to another). Private owners are constrained in the exercise of this prerogative in several respects: . Nuisance laws protect neighboring property owners and the public at large from harm caused by unreasonable use of private property, as considered in the case of Lummis v. Lily, 429 N.E.2d 1146, 1982. This case involved a stone groin on Cape Cod, Mas- sachusetts, and lists the factors to be applied in determining if the structure was "reasonable" and therefore immune from a damage claim by a neighbor. _ . ~ ~ ~ . . .. Covenants and deed restrictions can arise through private terms of a subdivision instrument of conditions, through retention of certain rights by a prior seller that "run with the land" or by other means. Such private restrictions, when legal in purpose and

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MANAGEMENT AND APPROACHES 49 recorded properly, are enforceable against private owners whose land is thereby encumbered. These restrictions include municipal/county zoning and subdivision regulations; state building codes, wetland and floodplain regulations, and coastal zone management regulations; and ~ federal environmental regulations. Developers/builders may or may not hold an ownership interest in the site in question. They may operate in partnership with the owner and/or with other investors. Professional developers/builders are held to a higher level of responsibility with respect to the quality and safety of the resulting structure than nonprofessional owners. The possibility of professional liability affecting the devel- oper/builder and professional advisors (e.g., architects, engineers, and lawyers) may be a constraint on unwise construction in erosion- prone locations. Homeowner associations are private nonprofit corporations es- tablished by a developer to own and manage the common facilities of a particular residential subdivision. An association also can serve as "watchdog" to enforce subdivision deed restrictions. The mem- bership of the association consists of the owners of all lots in the subdivision. In coastal areas homeowner associations may own and manage beach and shoreline property on behalf of the subdivision lot owners. Neighbors and other residents have a voice in the local zoning process through mandatory public notice and hearing provisions of state law. Lenders include banks, savings and loan associations, pension funds, insurance companies, and other institutions that finance land development. Lenders that are "federally related" (e.g., insured or regulated by federal agencies) are required to ascertain and inform borrowers as to whether a site is located within a "special flood hazard area" identified by the National Flood Insurance Program (NF1P). If so, the borrower is required to purchase flood insurance for the acquisition or improvement of structures on such a site (42 USC Section 4104a). This requirement could be extended to erosion- prone areas not now included in flood hazard zones. Realtors have a professional duty to disclose flood or erosion hazards known to them or ascertainable from published maps of the NF1P. Like developers, realtors can be held liable to a buyer for concealing or failing to ascertain the existence of such hazards.

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so MANAGING COASTAL EROSION Public Sector Public participants in coastal land development and management include . incorporated municipalities (e.g., villages, boroughs, towns, cities); counties; special districts; states; and the federal government. The roles performed by various tiers and units of government differ from one state and location to another, as discussed in the preceding section. Briefly, the principal roles of public entities that relate to development in erosion-prone coastal areas are the following: land ownership (e.g., national, state, local parks); police power (e.g., zoning, subdivision, environmental, and hazard mitigation regulations); . infrastructure funding and/or operation (e.g., roads, bridges, causeways, sewer and water lines); and ~ development (e.g., convention centers, cultural facilities, sports complexes). Not all of these roles pertain to each tier of public authority. The following matrix suggests, in general terms, the functions of respective types of governmental units, although these vary among states and localities (Table 3-1~. This matrix suggests that the role common to all levels of government is the funding and/or opera- tion of the physical infrastructure. This function typically requires multilevel participation In the form of funding, design, licensing, operation, and inspection of facilities. A national program for coastal erosion management must ad- dress the siting and design of public infrastructure that encourages development in erosion hazard areas. (Eroding shores within desig- nated units of the Coastal Barrier Resource System already are off limits to federal infrastructure funding and flood insurance under the CBRA of 1982.) In summary, the development and management of land subject to coastal erosion are influenced by the actions of diverse private and public participants. A national policy on coastal erosion must acknowledge this complexity and seek to achieve erosion/flood loss reduction through multiple approaches involving different classes of

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MANAGEMENT AND APPROACHES TABLE 3-1 Functions of Governmental Units 51 Infrastructure Coastal Police Provider/ Land Use Landowner Power Funding Developer Planning Municipality x x x x x Special district o x x County o x* x* x o S rate x x x x Federal x x x o NOTE: x, major role in most states; o, minor role in most states; and - , not a role in most states. Primarily for unincorporated areas. participants and actions (e.g., local planning and zoning, public land acquisition, withholding of infrastructure funding, and clarification of professional duties of lenders, developers, and realtors). All ap- proaches require improved public understanding of the nature and implications of coastal erosion. RELEVANT FEDERAL PROGRAMS Since the 1930s, Congress has created a variety of programs and initiatives relating to management of coastal areas, including the Great Lakes. These have pursued a number of objectives, some of them in conflict with others (e.g., navigation, national defense, public recreation, riparian rights, public trust for underwater lands, protection of fish and wildlife resources, economic development, miti- gation of pollution, and reduction of losses owing to natural hazards, including coastal erosion). Federal constitutional powers involved in these efforts have included spending power, taxation power, in- terstate commerce power, and regulatory police power. Approaches taken have varied widely from one program to another. Those of primary importance to this discussion are the following: 1. U.S. Army Corps of Engineers: coastal protection works, navigation improvements, and regulation of dredge and fill. 2. U.S. Department of the Interior: acquisition of national parks and national wildlife refuges.

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52 MANAGING COASTAL EROSION 3. U.S. Environmental Protection Agency: regulation of ocean dumping, discharges into waters of the United States, research on sea level rise, etc. 4. National Oceanic and Atmospheric Administration/Office of Ocean and Coastal Resource Management: funding and technical assistance to support state coastal zone management programs. 5. Federal Emergency Management Agency/Federal Insurance Administration: mapping of coastal hazard areas and administration of the NF1P. 6. Coastal Barriers Resources Act of 1982. The following sections briefly review these programs, followed by a more detailed discussion of the coastal aspects of the NF1P. U.S. Arnold Corps of Engineers The Army Corps of Engineers (COE) has been engaged in nav- igation improvements of the nation's waterways, both intracoastal and inland, since 1824. The Intracoastal Waterway extending from Texas to New Jersey began prior to World War IT and has con- tributed to the public enjoyment and economic development along the Atiantic and Gulf coastlines. COE river and harbor projects, such as channel dredging and inlet stabilization, have similarly pro- moted economic and recreational usage of estuarine areas, bays, and harbors along the nation's ocean and Great Lakes shorelines. COE coastal erosion activities have included the construction of seawalIs, jetties, and groin fields and beach restoration and nour- ishment projects. These projects have been approved by Congress with varying cost-sharing ratios. The nonfederal percentage of to- tal project costs varies depending on local interest; however, many project costs are shared on a 50/50 basis. Since 1970 the National En- vironmental Policy Act has required that an Environmental Impact Statement be prepared for COE coastal protection and navigation projects, which are deemed to be "major federal actions significantly affecting the human environment." In addition to its civil works functions, the COE administers several permit programs regulating the discharge of material into navigable waters and all construction therein. Of particular rele- vance to the management of coastal areas subject to erosion and sea level rise, COE administers (except in Michigan where the state has assumed 404 administrative authority) the "dredge and fill" permit

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MANAG~ENT AND APPROACHES 53 program under Section 404 of the Federal Clean Water Act. Pur- suant to guidelines established by the U.S. Environmental Protection Agency (EPA), COE must approve any proposed construction includ- ing dredge or fill in "waters of the United States," including wetlands bordering navigable waters (Platt, 19873. In cooperation with EPA, COE thus plays a critical role in relicensing of large- or small-scare development in coastal and estuarine wetlands. This encompasses much of the ongoing development in areas subject to coastal floods and erosion. U.S. Department of the Interior The National Park Service (NPS) and the Fish and Wildlife Service (FWS) of the Department of the Interior (DON) own and manage substantial land holdings along the nation's eroding coast- lines. Each agency controls extensive areas of open coast shorelines, coastal barriers, estuarine wetlands, zones of fish migration, and eroding shorelines on the Great Lakes. Most NPS areas subject to coastal erosion are located within the nation's 10 national seashores and four national lakeshores. These were established during the 1960s and 1970s, beginning with the authorization of the Cape Cod National Seashore in 1961 (Cape Hatteras was designated a national park in 1937~. Coastal erosion has adversely affected many of these facilities, notably Cape Cod, where a single winter storm in 1978 destroyed parking lots, access roads, visitor facilities, and a national landmark, the "Outermost House." The Cape Hatteras Lighthouse is another major national historic landmark managed by the NPS that is threatened by coastal erosion. An NRC study of options to preserve that lighthouse recom- mended that it be moved landward rather than constructing shore protection structures (National Research Council, 1988~. Another NPS area threatened by severe coastal erosion is Indiana Dunes Na- tional Lakeshore. Jetties built during the 1970s have interfered with sediment transport and caused the loss of most of the area's once impressive sand beach. (In 1989, some beach has reappeared with lower lake levels.) FWS administers the National Wildlife Refuge System, along with several dozen units in coastal areas. In some cases, such as Assateague Island (Maryland and Virginia), FWS manages a wildlife refuge directly adjacent to an NPS facility. Wildlife refuges by def- inition have few human-made artifacts to be threatened by coastal

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54 MANAGING COASTAL EROSION erosion. Nevertheless, the gradual submergence of existing wetland habitat ~ an important long-term issue for the FWS. U.S. Environmental Protection Agency The EPA promulgates guidelines for the adrn~nistration of the Section 404 Dredge and Fid Program for coastal and inland wet- lands. An important provision of these guidelines is that non-water- dependent uses are disfavored in wetlands. The COE cannot issue a Section 404 dredge and fill perrrut for such an activity if an am propriate upland site is available. The burden of proof lies with the applicant to demonstrate that such a site ~ not available. To obtain parrots in Unprotected areas, the applicant must provide Mitigation" of adverse impacts through appropriate design, location, and, in some cases, restoration or creation of other wetlands. Building techniques designed to mitigate harm to wetlands also may be useful in averting threats to the same structures from storm surge and shore erosion. EPA is also conducting a series of studies of major embayments under the National Estuary Program. National Oceanic and Atmospheric Administration The Coastal Zone Management (CZM) Act of 1972 established a joint federal-state process for coastal zone planning and management. The federal CZM program is administered by the Office of Ocean and CoastalResource Management (OCRM) of the National Oceanic and Atmospheric Administration (NOAA). The act declared a national policy favoring better management of coastal land and water re- sources, cited the need for federal-state collaboration in planning for nonfederal portions of the coastal zone, and authorized funds to assist states in developing and administering their own coastal management plans. The federal CZM program does not set mandatory federal stan- dards, nor does it require the issuing of fecleral licenses or permits by OCRM. Instead, the program facilitates state and local coastal zone planning through funding and technical assistance. To be eligible for OCRM funding, a state plan must address a number of pub- lic policy issues, such as navigation, habitat protection, economic development, public recreation and access to shorelines, scientific research, energy development, and natural hazard mitigation. As of 1989, 29 of the 35 eligible states and territories bordering oceans and

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60 MANAGING COASTAL EROSION profile after construction of a seawall is similar to the preconstruction shape if a sediment supply exits, showing the same number of bars with approximately the same volumes and relative locations. The form of the erosional response to storms at seawalls is typically different. Limited evidence indicates that the subaqueous nearshore profile on a sediment-deficient coast with seawalls does not steepen indefinitely, but approaches an equilibrium configuration compatible with the coarser-grained particles comprising the bottom sediment. As pointed out by Dean (1986), the only principle that is def- initely established is the one of "sediment conservation." Coastal armoring (e.g., a riprap or seawall) neither adds to nor removes sand from the sediment system but may be responsible for the redistri- bution of sand and can prevent sand from entering the system. Al- though armoring can cause additional localized scour during storms, both in front of and at the ends of the armoring, there are no fac- tual data to support claims that armoring causes profile steepening, increased longshore transport, transport of sand to a substantial distance offshore, or delayed poststorm recovery. Low-profile seawalIs or dikes can be used to retain a beach or fillet of sand above the normal beach profile level. Such structures are referred to as perched beaches and may exist as single-level or terraced structures. OFFSHORE BREAKWATERS Offshore or detached breakwaters typically are constructed from rock or concrete armor units and protect the shoreline by reducing wave energy reaching it. They also promote sediment deposition leeward of the structures. Most offshore breakwaters built for shore protection are segmented and detached; thus, they provide substan- tial protection to the shoreline without completely stopping Tong- shore sand transport. They do not deflect and relocate currents, like breakwaters that project from the land. Unlike seawalIs, revetments, or bulkheads, breakwaters aid in the retention of the beach because they reduce wave energy. A main disadvantage is that they are more expensive to build than land-based structures. Segmented, detached breakwaters have been used successfully to protect shorelines from erosion in many countries such as Japan, Spain, Italy, and Israel. The use of these structures in the United States has been limited to a few sites in Massachusetts, Ohio, Penn- sylvania, Virginia, and Hawaii. Submerged breakwaters, or artificial reefs, have been used in many parts of the world, notably in Italy but recently in Florida. They may be composed of sunken barges or ships

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MANAGEMENT AND APPROACHES 61 or any heavy objects that break up wave action. The costs can be much less then for breakwaters that project above the water surface because they do riot have to absorb the full wave impact, but merely cause storm waves to break and spill their energy in turbulence. SAND BYPASSING Inlets, navigation channels, and harbor entrances all interrupt the natural flow of sediment transport along the shoreline. The interrupted flow of sand is diverted either offshore in ebb tide shoals, into bays or lagoons in flood tide shoals, or in navigation channels. They generally cause shoaling and downdrift migration of channels, which require frequent dredging in order to maintain safe navigation. As a result, erosion occurs downdrift of the interrupted coastline. Sand bypassing, by either a fixed or floating pumping system, restores the natural flow of sand to the downdrift shorelines and reduces the need for channel dredging. Successful operations of this type exist in many countries such as Australia, Japan, and South Africa. In Florida the use of two fixed bypassing plants for a period of 30 years suggests the feasibility of such systems to alleviate human-induced erosion downdrift from inlet control structures. Floating dredge (temporary) bypass operations also have been used in the United States. One example is a federal project at Channel Islands Harbor, California, where over 1 million cubic yards of sand is bypassed on a biennial basis past two harbor entrances to restore eroding downdrift beaches (Herron and Harris, 1966~. DUNE BUILDING Natural sand dunes are formed by winds blowing onshore over the beach, transporting sand landward. Grass and sometimes bushes grow on sand dunes, creating a natural barrier against sea attack. The dunes provide a reservoir of beach sand during severe storms and thus help prevent flood and wave damage to adjacent property. In areas where substantial dunes exist, the poststorm beach width can be greater than the prestorm width. Attempts have been made to mimic nature by promoting the for- mation of artificial dunes. Artificial dunes have been created in many countries around the world, as well as in the United States. States where large-scale dune construction has occurred include North Car- olina, Texas, Florida, and New Jersey.

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62 MANAGING COASTAL EROSION Building and [and Use Management Since the advent of the NF1P in 1968, legal and institutional ~ "nonstructurally ~ measures have become unport ant mechanisms used to reduce the vulnerability of coastal and riverine structures to flood and erosion losses. Planners have often seen engineered responses to coastal erosion as unsuitable from an economic and environmental perspective, especially when used to protect privately owned, lower density residential development. One prorn~sing approach to coastal management Is to influence the location, elevation, and design of new or substantially redeveloped structures through public building and land use controls. The NF1P in particular has fostered the adoption of floodplain management standards by some 1200 coastal communities nationally, containing an estimated 43 million people (Congressional Research Service, 1987~. Like their counterparts along inland floodplains, these communities must require minimum elevation of new structures above estimated Midyear flood ("base flood") levels that include the effect of wave heights. These land clevelopment restrictions generally have been held to be constitutional (KusTer, 1982~. SETBACK REQUIREMENTS Coastal construction standards under the NF1P have emphasized elevation rather than horizontal displacement. New buildings on substantial pilings up to 20 feet above grade are a familiar site in recently built communities along the AtIantic and Gulf coasts. But horizontal displacement is required under the flood insurance program's minimum standards, only to the extent that new buildings in coastal high-hazard zones (V-zones) (see Figure 3-2) must be "located landward of the reach of mean high tides and must not alter dunes or mangrove stands (44 CFR Section 60.3(e)~. Even these minimal requirements do not apply to coastal A zones (e.g., bayside or other non-open ocean shorelines). Where either V-zone or A-zone coastal shores are experiencing erosion, further horizontal displacement of new or rebuilt structures is needed. A number of coastal states have established horizontal setbacks for new construction at the individual state level (Hildreth, 1980; Maloney and O'Donnell, 1978~. According to an unpublished NOAA memorandum (Houlahan, 1988), there are three basic approaches states have taken: (1) natural resource protection statutes, (2) fixed setback lines, and (3) average annual recession rate setbacks. The

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63 CD C C17 "o ~ C) ' E , _ CO Cal In ~ ~ ~ - ._ a) I a) CO Ct a) a) .= Ill a,) ii~ > ~o ~ = ~ ._ e~ ~ m ~ 1 a) 1 _ 1~ I _ ~ ._ 1 1 ~ / cn >, 0 0 CO c as~t _ S" a) ._ a o ._ ~ _ m ~ o C) ~ a. Ct _ a) c - o a a, o c c cn c ._ c cn o m o o _ 'e ~q - - e~ co -

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64 MANA GING COASTAL EROSION first category includes states such as Massachusetts and Wisconsin that place limitations upon development in wetlands or on dune systems. These requirements are not specifically designed to address erosion. Fixed setback lines involve a minimum specified distance (e.g., 100 feet in Delaware) from a reference feature. Types of physical reference features include (1) seaward toe of primary dunes, (2) line of vegetation, (3) edge of eroding bluff, (4) mean high water, or (5) a specified elevation contour. These features may move whenever erosion occurs. Florida established a "coastal construction control line" for each of its 24 sandy beach coastal counties based on the estimated in- land reach of a Goodyear storm event. Construction is not prohibited seaward of this line, but a state permit must be obtained and con- struction must conform to state design standards (Shows, 1978~. At least seven states use "average annual erosion rate" (AAER) setbacks to mark the minimum setback for new construction. Michi- gan and North Carolina impose a 30-year setback on smaller struc- tures; North Carolina also imposes a 60-year setback on larger ones. These guidelines have been incorporated into the Upton-Jones Amendment to the NF1P. (See further discussion in Chapter 4.) THE TAKING ISSUE Since the late 1960s, land use and building regulations have been applied widely by states and local governments to regulate devel- opment in areas subject to special limitations such as floodplains and wetlands. Such regulations often impose severe restrictions on the rights of private landowners to fill or build in designated flood hazard or wetland areas. A variety of such measures were challenged in court during the 1960s and early 1970s under the theory of "tak- ing issue," that is, that the measure is so restrictive that it "takes" the value of the property without compensation in violation of the Fifth Amendment to the U.S. Constitution. Despite some early set- backs (e.g., Morris County Land Investment Co. v. Township of Parsipanny-Troy Hills, 193 A. 2d 232, New Jersey t1963], most de- cisions have upheld the public regulations. Two landmark opinions issued in 1972 in Massachusetts (Turnpike Realty Co. v. Town of Dedham, 284 N.E. 2d 891~) and Wisconsin (Just v. Marquette County,

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MANAGEMENT AND APPROACHES 65 201 N.W. 2d 761) upheld public restrictions in a riverine floodplain and a lakeshore wetland, respectively. Relatively few judicial decisions have been concerned specifically with measures intended to mitigate the effects of coastal flooding and erosion. An early California opinion (McCarthy v. City of Manhatten Beach, 264 P. 2d 932 t19544) upheld a "beach recreation districts that prevented the owner of three-fifths of a mile of Pacific beach shoreline from building on his property. In upholding the zoning measure, the court noted that the property "is, from time to time, subject to erosion and replacement by reason of storms and wave action of the Pacific Ocean" (264 P. 2d, at 934~. Prevention of construction in areas known to have been inundated in Pacific coastal storms in the 1930s was held to serve a valid public purpose. The right to charge admission to users of this private beachfront was considered adequate economic return to the owner. A 1966 New Jersey decision (Spiegle v. Borough of Beach Haven, 218 A. 2d 129) specifically addressed public setback regulations de- signed to mitigate coastal flooding and erosion hazards on an Atlantic Coast barrier island. Beach Haven prohibited new construction sea- ward of a building line established 20 feet inland of a designated dune area. The New Jersey Supreme Court sustained this setback regulation in the strongest possible terms: {Cams l - I ^~A ~1~1 ~~' +~+ ~ ~er~l~1 1~^ ~o^~ +~ ~ 51= VV&V~~54& . . . CULL ~~&l=lJl~UU=~ illV1 U~la~U MU ~V~~ ~= ~~1~1= US construct houses oceanward of the building line . . . because of the possibility that they would be destroyed during a severe storma result which occurred during the storm of March 1962. Additionally, defendant submitted proof that there was great peril to life and health arising through the likely destruction of streets, sewer water and gas mains, and electric power lines in the proscribed area in an ordinary storm. The gist of this testimony was that such regulation prescribed only such conduct as good husbandry would dictate that plaintiffs should impose on the use of their own lands. (218 A.2d, at 135) Although the Spiegle decision technically is limited in its effect to New Jersey, it provides a rationale that could be adopted by state courts elsewhere. Surprisingly few opinions have appeared in the last two decades concerned with coastal setbacks per se (e.g., Town of Indialantic v. McNulty, 400 So. 2d 1227, Florida [1981~. In view of the widespread approval of floodplain and wetland regulations gen- erally, there is a strong legal basis for the broader use of setbacks for coastal construction based on the best available scientific estimates of future erosion rates.

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66 RELOCATION MANAGING COASTAL EROSION Relocation of existing structures from eroding and/or flood- prone shorelines has long been a neglected mechanism for respond- ing to shoreline retreat. The technical feasibility of moving small or medium-size structures has been established. As early as 1888, a three-story seaside hotel was moved in one piece a distance of 495 feet landward from an eroding shoreline at Money Island, New York (Scientific American, 1888~. In 1988, the National Research Council (NRC) Committee on Options to Preserve Cape Hatteras Lighthouse recommended that the 2,80~ton lighthouse be relocated physically in preference to in situ efforts to stabilize the retreating shoreline (National Research Council, 1988~. The committee concluded that moving the lighthouse would be technically and economically feasi- ble. Relocation as a widespread adjustment to shore erosion is most likely to be cost effective for smaller structures, particularly one- and two-story residential buildings. Private residential development usually is not eligible for federally sponsored shoreline protection projects. Certain states, including North Carolina and Maine, dis- courage or prohibit further hardening of residential shorelines, al- though "soft" forms of stabilization such as beach nourishment may be permitted (e.g., in several Florida communities where nonfederal beach nourishment has been accomplished). Relocation encounters a number of institutional and economic impediments. Structures on deep lots may gain sufficient protection by relocating landward on the same lot (the most common practice in Michigan). However, if sufficient space is not available on the same lot, an alternative site must be acquired and prepared. This increases the cost of relocation substantially. It also may incur problems of zoning; mortgage refinancing; and provision of sewer, water, and road access. The alternative site may lack the view and/or direct shoreline access that are often the reason for waterfront property ownership. However, a structure threatened by imminent collapse essentially is valueless and poses substantial potential costs to the community in terms of lost tax revenue, deterioration related to disinvestment/ abandonment, clearance of wreckage, casualty Toss deductions from income tax liability, disaster relief payments, and flood insurance loss payments. Relocation therefore may be a desirable public goal (e.g., through Upton-Jones payments as discussed in Chapter 4~. Relocation involving any public subsidy of support should involve

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MANAGEMENT AND APPROACHES 67 a landward distance at least equal to established setbacks for new construction. CONSTRUCTION REQUIREMENTS Damage to structures located along the shore in some cases can be reduced by relatively straightforward engineering and con- struction procedures to ensure the building's survivability during a 100-year storm event. In particular, the following is recommended if the building is likely to be subject to damage during the event: 1. The lower horizontal structural members should be elevated above the lQO-year wave crest elevation, the calculations taking into account the eroded profile. 2. Pilings on low dunes should be embedded to an adequate depth to ensure structural integrity during a 100-year storm tide and associated erosional event. 3. Connections of structural members should withstand antic- ipated 100-year wind loading. Although the above would increase cost of construction in the coastal zone, the effect would be to reduce substantially the demoli- tion claims against the program and increase the relocation activity following storms. As proposed, these recommendations would only be effective for new structures; however, the economic feasibility of retrofitting existing structures within a designated erosional zone should be investigated. To ensure construction in accordance with requirements discussed here, certification should be required by a registered engineer or architect. OTHER COMMUNITY MANAGEMENT TOOLS A [and acquisition program is another strategy to cope with coastal erosion management. This is appropriate where erosion- prone areas can be acquired and preserved for recreation, open space, or other appropriate public purposes. Such programs generally in- clude specific criteria and priorities for acquisition, identify funding sources, and set timetables for action. Potential federal funding sources include, among others, Section 1362 of the National Flood Insurance Act, the Land and Water Conservation Fund, and Section 306A of the Federal Coastal Zone Management Act. The community plans also can identify state and local resources that will be devoted to this program.

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68 MANAGING COASTAL EROSION The scope and ~rnplementation of both the relocation and acqui- sition programs adopted should be a factor in setting flood insurance rates for the community. This would ensure that policy holders in those communities doing the most to prevent future flood and erosion losses receive the greatest benefit. This integration of the insurance and erosion management aspects of the programs through community risk assessment could be a critical aspect of producing an actuarially sound program that effectively encourages loss prevention. Public infrastructure investment includes financing coastal ero- sion structures where appropriate (e.g., nourishment, seawalIs, jet- ties, and breakwaters). It also includes the location of public infra- structure (e.g., roads, water pipes, and sewers) that influences the location and density of developments and poststorm redevelopment, roads, water, sewer, and the like and those planned to reduce fu- ture losses. Plans and standards can be adopted to assure that new public development itself is located away from erosion hazard areas where such is feasible and is designed to avoid inducing additional private development in hazard areas. Where applicable, attention also can be given to establishing a program to identify and finance appropriate shore protection investments. Community education programs can inform land owners, devel- opers, realtors, purchasers, and the public about flood and erosion hazards, associated public cost, and local management requirements for hazard areas. These programs can include the physical posting of signs showing flood elevations, flood boundaries, and the poten- tial extent of erosion and the ready availability of flood hazard and erosion rate maps. SUMMARY This chapter has reviewed several variables that influence the management of coastal erosion areas. These include diversity of (1) physical shoreline type (as reflected in different degrees of suscepti- bility to erosion), (2) settlement types and patterns, and (3) political governance. Furthermore, private and public interests play various roles from one segment of shoreline to another. This chapter summa- rized federal coastal programs with which the NF1P must interact. The NF1P itself is a primary vehicle for implementing a national erosion policy and is the subject of the next chapter. Finally, this chapter has reviewed methods of response to erosion hazards that include both engineered and nonengineered measures.

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MANAGEMENT AND APPROACHES 69 The former include "hard" projects, such as seawalls, jetties, groin fields, and breakwaters, as well as "soft" measures, notably beach nourishment and dune restoration. Nonengineered measures include land use and building regulations and relocation, retrofitting, or demolition of existing structures. REFERENCES Burton, I., R. W. Kates, and R. E. Snead. 1968. The Human Ecology of Coastal Flood Hazard in Megalopolis. Research Paper No. 115. Chicago: University of Chicago Department of Geography. Congressional Research Service. 1987. Managing Coastal Development Through the Coastal Zone Management and Flood Insurance Programs: Experi- ence to Date and the Views from Selected States. Report ENR 88-254. Washington, D.C.: CRS, p. 28. Dean, R. G. 1986. Coastal Armoring: Effects, Principles and Mitigation. Twen- tieth Coastal Engineering Conference: Proceedings of the International Conference, November 9-14, 1986, Taipei, Taiwan, ASCE, Vol. III, Chap- ter 135, pp. 1843-1857. Dean, R. G. 1989. Sediment interaction at modified coastal inlets: Processes and policies. Pp. 412-439 in Hydrodynamics and Sediment Dynamics of Tidal Inlets, Lecture Notes on Coastal Estuarine Studies, 29, D. Aubrey and L. Weishar, eds. Berlin: Springer-Verlag. Herron, W. J., and R. L. Harris. 1966. Littoral Bypassing and Beach Restoration in the Vicinity of Port Huer~eme, Calif. Proceedings, 10th Conference on Coastal Engineering, Tokyo, Japan, September 1966, ASCE, Vol. 1, pp. 65 1-675. Hildreth, R. 1980. Coastal natural hazards management. Oreg. L. Rev. 59:201. Houlahan, J. M. 1988. Analysis of state construction setbacks to manage devel- opment in coastal high hazard areas. Unpublished NOAA memorandum, April 26. Kraus, N. C. 1987. The Effects of Seawalls on the Beach: A Literature Review. Proceedings, Coastal Sediments '87, New Orleans, Louisiana, May 12-14, 1987, ASCE. Kraus, N. C. 1988. The Effects of Seawalls on the Beach: Extended Literature Review. J. Coastal Research, Special Issue No. 4, Autumn 1988, pp. 1-28. Kusler, J. A. 1982. Regulation of Flood Hazard Areas to Reduce Flood I~osses. Washington, D.C.: U.S. Water Resources Council. Maloney, F. E., and A. J. O'Donnell. 1978. Drawing the line at the oceanfront: The development of the coastal zone. U. Fla. L. Rev. 30:383. National Research Council. 1988. Saving Cape Hatteras Lighthouse from the Sea, Options and Policy Implementations. Washington, D.C.: National Academy Press. O'Brien, M. P., and J. W. Johnson. 1980. Structures and Sandy Beaches. Coastal Zone '80, Hollywood Beach, Florida, November 17-20, 1980, ASCE, Vol. IV, pp. 2718-2740. Platt, R. H. 1985. Congress and the coast. Environment 27~6~:12-17, 34-39. Platt, R. H. 1987. Coastal wetland management. Environment 29~9~:16-20, 38-43.

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70 MANAGING COASTAL EROSION Platt, R. H., S. G. Pelczarski, B. K. R. Burbank. 1987. Cities on the Beach: Management Issues of Developed Coastal Barriers. Research Paper No. 224. Chicago: University of Chicago Department of Geography, p. 43. Scientific American. April 14, 1888. Moving the Brighton Beach Hotel, p. 230. Shows, E. W. 1978. Florida's coastal setback linean effort to regulate beach front development. Coastal Z. Mgmt. J. 4~1/2~:151-164. U.S. General Accounting Office. 1982. National Flood Insurance: Marginal Im- pact on Floodplain Development. CED-82-105. Washington, D.C.: General Accounting Office. U.S. General Accounting Office. 1988. Flood Insurance: Statistics on the NFIP. GAO/ACED 88-155FS. Washington, D.C.: General Accounting Office.