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Executive Summary
The nation's beaches- transition zones between land and sea provide a
measure of protection to the shore from damage by coastal storms and hurricanes.
Their effectiveness as natural barriers depends on their size and shape and on the
severity of storms. Beaches are also highly valued as recreational resources.
Visiting beaches has become synonymous with coastal recreation. Beach ameni-
ties are an important factor in the commercial and residential development of
most upland areas behind beaches. In the past, development of coastal areas often
began behind dunes or in back bay areas, which provided substantial buffers
between buildings and the sea. However, modern development of beach areas has
predominantly occurred in close proximity to the beachfront and has often re-
sulted in the replacement of dune systems with buildings. This practice has in-
creased the exposure of buildings to damage from natural forces. Most beaches
are naturally eroding when observed over long enough time spans to average out
large seasonal variations. The existence of buildings relative to an eroding shore-
line results in a reduction in beach width, adversely impacting both natural storm
protection and the recreational quality of affected beaches.
A number of engineering approaches have been used to counteract the ef-
fects of erosion by stabilizing or restoring beaches. Traditional protective mea-
sures have included "hard" structures such as seawalls, revetments, groins, and
detached breakwaters. These structures can reduce flooding hazards, armor the
coastline, reduce wave attack, and stabilize the beach. None of these shore pro-
tection structures, however, adds sand to the beach system to compensate for
natural erosion. Beach nourishment stands in contrast as the only engineered
shore protection alternative that directly addresses the problem of a sand budget
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BEACH NOURISHMENT AND PROTECTION
deficit, because it is a process of adding sand from sources outside the eroding
system. The result is a wider beach that improves natural protection while also
providing additional recreational area. Beach nourishment serves as a sacrificial
rather than fixed barrier. The sacrificial nature of beach nourishment projects and
public misconceptions about how beach fill projects are supposed to perform
have been the source of much controversy.
Although proven engineered shore protection measures exist, there are no
quick, simple, or inexpensive ways to protect the shore from natural forces, to
mitigate the effects of beach erosion, or to restore beaches, regardless of the
technology or approach selected. Available shore protection measures do not
treat some of the underlying causes of erosion, such as relative rise in sea level
and interruption of sand transport in the littoral systems, because they necessarily
address locale-specific erosion problems rather than their underlying systemic
causes. Further, all shore protection and beach restoration alternatives are contro-
versial with respect to their effects on coastal processes, effectiveness of perfor-
mance, and socioeconomic value. Beach nourishment, the subject of this report,
has received widespread national attention in the print and broadcast news media
and in the federal government.
Most coastal engineering practitioners consider beach nourishment a techni-
cally sound engineering alternative when properly designed and placed in an
appropriate location. Beach nourishment projects in some locales have performed
better than predicted, whereas others have performed more poorly than predicted.
In some cases, often as a result of inappropriate or uninformed perceptions about
project performance, public expectations have not been met even when design
performance criteria were achieved. The adequacy of beach nourishment design
methodology has been a source of controversy. Some of the criticism has stemmed
from a perception that coastal geological factors have been undervalued or ne-
glected. As a result of questions about actual project performance, the use of
beach nourishment has encountered strong local, regional, and national opposi-
tion. Opponents often view the sacrificial aspect of beach nourishment as little
more than building sand castles to protect against an advancing sea. The contro-
versy over the technical merits of beach nourishment has been exacerbated by
national concerns over the economic effects of beach restorations, the appropriate
way in which to account for flood protection benefits derived from a beach
nourishment project or program (a series of beach nourishment projects) in the
National Flood Insurance Program, and the role of beach nourishment in federal
disaster assistance. The suitability of beach nourishment as an engineering alter-
native in shore protection has thus been fundamentally challenged.
Advancing the state of practice of beach nourishment requires an improved
understanding of project location, complex shoreline processes, prediction, de-
sign, cost-benefit analysis, sand placement and distribution, cost-sharing alloca
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EXECUTIVE SUMMARY
3
tons, and monitoring. This report provides technical descriptions and analyses of
these critical areas. In so doing, it addresses six basic questions:
· Does beach nourishment work?
· How should success be measured?
· Is beach nourishment economically justified?
· How can beach nourishment applications be improved?
· What is the appropriate role of fixed structures with respect to beach
nourishment?
· What is the role of beach nourishment in flood protection and disaster
assistance?
The report addresses these questions to improve the technical basis for public
policy decision making. The inducement of shore development that might result
from a beach nourishment project or program is an important public policy issue,
but it is beyond the scope of this report except with respect to identifying an
economic valuation methodology and monitoring program that would provide
the technical basis for decision making. Major conclusions and recommendations
are presented here in summary format. Chapter 7 contains the committee's com-
plete conclusions and recommendations.
DOES BEACH NOURISHMENT WORK?
Beach nourishment is a viable engineering alternative for shore protection
and is the principal technique for beach restoration; its application is suitable for
some, but not all, locations where erosion is occurring. Beach nourishment can
provide protection from storm and flooding damage when viewed within human
time scales (decades not centuries) in those situations where its use is technically
feasible, provided that:
.
.
erosion rates are effectively incorporated into project design and, ideally,
the erosion cause is reduced;
state-of-the-art engineering standards are used for planning, design, and
construction; and
projects are maintained according to design specifications.
Further, to provide valid predictions, uncertainties must be realistically accounted
for in design, construction, and maintenance. Beach nourishment may not be
technically or economically feasible or justified for some sites, particularly those
with high rates of erosion. Government authorities with responsibility for coastal
protection should view beach nourishment as a valid alternative for providing
natural shore protection and recreational opportunities, restoring dry beach area
that has been lost to erosion.
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BEACH NOURISHMENT AND PROTECTION
HOW SHOULD SUCCESS BE MEASURED?
There is no single measure of successful beach nourishment projects because
projects usually serve several objectives. Further, a project may be successful in
meeting some but not necessarily all objectives that led to its implementation.
Project sponsors should establish the specific performance criteria that will be
used and how performance will be measured and assessed as an essential element
of the design process for each project.
The immediate measures of success that should be quantified and reported
are dry beach width, volume of sand remaining after storms, poststorm damage
avoidance assessments, and flood protection capability. Subaqueous sand vol-
umes should also be measured because they contribute to protection from storm
waves and to recreational value.
Realization of projected economic benefits and reduction of shoreline retreat
should also be measured, although the effects are more likely to occur over a
longer term than the other performance measures. Effective project performance
from an engineering perspective may or may not result in the changes in eco-
nomic conditions desired by local sponsors of projects because socioeconomic
conditions can change over the life of a beach nourishment program.
IS BEACH NOURISHMENT ECONOMICALLY JUSTIFIED?
Assessing and Allocating Costs and Benefits
Beach nourishment projects result in economic benefits in a variety of forms
and to a variety of recipients. Cost-share ratios for projects in which there is
federal involvement do not necessarily describe the actual distribution of the
benefits or adequately account for the impact of navigation projects on nearby
and down-coast shorelines. All benefits that accrue from a beach nourishment
project should be assessed and quantified, and cost sharing should more accu-
rately account for the spread of benefits to the various recipients. The federal
share needs to appropriately incorporate any adverse erosion impacts of federal
navigation projects on nearby and downdrift shorelines.
Cost-Benefit Analysis
The theory and methodology for conceptualizing and measuring costs and
benefits are well developed but are not systematically applied for the valuation of
beach nourishment projects. Social costs and benefits are not always fully repre-
sented in decision making about whether to undertake a project and which of the
alternative project designs and implementation strategies to select. Federal proce-
dures for calculating costs and benefits are overly restrictive, and they need to
include the full range of potential costs and benefits; that is, the full complement
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EXECUTIVE SUMMARY
s
of recreation benefits and the beneficial effects to adjacent beaches outside the
project limits are to be appropriately accounted for. The U.S. Army Corps of
Engineers (USAGE) rules governing its cost-benefit analyses, and the choices
among alternative project design and implementation strategies, need to account
for the true social costs and benefits in decision making. Federal policy should
recognize the storm damage reduction and recreation values to the total area
affected, including the benefits of sand being transported to adjacent areas out-
side a nourishment project's boundaries. To improve the technical basis for as-
sessment of costs and benefits, the USACE could conduct postconstruction eco-
nomic evaluations to identify and measure the wide range of costs and benefits
that actually result from beach nourishment projects and programs. To present
state-of-the-art economic valuation methodology more effectively and to provide
an improved basis for policy analysis and decision making, the USACE should
incorporate and consistently apply an up-to-date economic valuation methodol-
ogy, especially for measuring nonmarket benefits such as recreation.
In the committee's view, physical interactions between the costs and benefits
of adjacent federal navigation and beach nourishment projects have not been
effectively correlated. The erosion mitigation and nourishment needs of beaches
affected by navigation projects have not been adequately recognized or accom-
modated in the planning and implementation of navigation projects, in order to
minimize disruption of the littoral system. To conserve and use sand resources
optimally, the USACE should modify its policies to require that beach-quality
sand dredged from federal navigation projects be placed in the littoral system
from which it was removed rather than offshore. The cost of offshore disposal is
greater than has been estimated in the past, when only the direct cost of offshore
disposal was considered. The USACE should modify its cost-benefit procedures
to accurately account for the economic value of sand and to consider the cost-
benefit relationships between federal navigation and beach nourishment projects.
A navigation project should be "charged" the cost of any sand budget deficit that
it might impose on adjacent shorelines and the littoral system.
Improving Cost-Benefit Analysis
The USACE could improve the basis for economic evaluation of beach
nourishment projects by reassessing the categories of costs and benefits that God+
inclusion in project evaluation, incorporating uncertainties in assessing costs and
benefits both with and without the project, investigating behavioral responses
stimulated by beach nourishment projects and associated policy issues, consider-
ing the coupling of projects with local growth and land-use plans to increase the
net benefits of projects, and designing incentive-based financing schemes. Post-
construction economic surveys to identify and quantify the full range of cost-
benefit components should also be conducted to establish a more complete and
accurate measure of the actual costs and benefits.
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BEA CH NO URISHMENT AND PROTECTION
HOW CAN BEACH NOURISHMENT
APPLICATIONS BE IMPROVED?
An up-to-date design methodology and certain technical improvements
are needed to advance the state of practice in beach nourishment project design,
construction, and maintenance. The great diversity of conditions, the mix of
coastal processes, and the resulting major regional differences make it neither
practical nor desirable to establish a national standard design for beach nourish-
ment projects. Each project must therefore be designed to satisfy the conditions
of its location. However, project design is hampered by limitations in our under-
standing of coastal processes and substantial uncertainties in numerical evalua-
tions of shoreline change. A more complete understanding of the underlying
causes of beach erosion at project sites and an ability to model and evaluate
coastal processes quantitatively are needed to improve project design.
Differences exist in the planning and design methodologies employed by the
USACE field offices. Although some of these differences are necessary to ac-
commodate regional differences in beaches, others have resulted from local modi-
fications of the agency's design methodology and have not realistically employed
the state of the art. Where they have not, uneven effectiveness and less-than-
optimum project design have resulted. The USACE should develop and imple-
ment a consistent methodology for beach nourishment design while retaining
sufficient flexibility to accommodate regional variations in physical conditions.
The Shore Protection Manual published by the USACE is technologically
outdated; yet it remains the de facto standard for coastal engineering, including
the design of beach nourishment projects, throughout most of the world. Engi-
neers in private practice in the United States are compelled to continue using it
because of strong legal constraints and liability considerations even though the
USACE no longer uses the manual as its design standard. The USACE should
publish detailed and comprehensive state-of-the-art engineering guidance on the
design of beach nourishment projects.
The updated design methodology should establish procedures for innovative
sand placement and corrective action to accommodate the significant spatial
alongshore variation, high erosion or accretion, that routinely occurs in nourished
beaches. Design profiles should be based on natural profiles at the site that are
suitably adjusted for nourishment grain size. Analytical and numerical models
should be used to estimate end losses that will be caused by spreading of sand to
adjacent beaches. Safety factors should be developed to account for variability
and uncertainty, including the possibility of erosional hot spots, and should be
appropriately applied to both design volumes and advanced-fill volumes. Fill
volumes should be adjusted to account for rock outcrops and seawalls in order to
provide sufficient volume to nourish the entire profile from the berm or dune to
the seaward limit of the active profile and to avoid underestimating fill require-
ments. Sediment performance characteristics should be included in the design
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EXECUTIVE SUMMARY
7
analysis. The first renourishment time interval could be shortened to allow for
uncertainties in alongshore erosion rates; erosional hot spots can then be cor-
rected before the design performance criteria are violated, and overbuilding of
those areas in which the beach is widening through accretion can be avoided. All
these methods should first be used in conjunction with overfill and renourishment
considerations and then as a substitute for these methods as more experience is
gained with actual project performance.
Management and Public Policy
Public Involvement
Public involvement in project development is not always adequate. This
situation has contributed to misunderstandings and controversy over project costs,
benefits, and performance. Project sponsors should establish public information
and involvement programs as an integral component of the beach nourishment
project at all stages. The public involvement programs should continue for the
life of the beach nourishment program to update the interested and affected
populations periodically on individual project performance and future plans and
actions. The public involvement programs ought to address design expectations
for beach behavior; adjustments in profile associated with construction tech-
niques; uncertainties with respect to design, prediction, future environmental
conditions, and storms; the replenishment program and interim corrective actions
that may be needed; and project costs.
Availability of Nourishment Material
Increasing demands for sand, both for nourishment projects and for other
uses, will make it increasingly difficult to predict the price at which sand will be
available in the future. This uncertainty is of particular concern to beach nourish-
ment programs because of the need to plan for a series of renourishment projects
over a long time and because of the difficulties in predicting costs and benefits
over a program's life.
If public sand sources that are free to publicly funded beach nourishment
projects in a state become insufficient to provide sediment of appropriate quality
for the planned life cycle of a nourishment program, sand sources outside that
state's jurisdiction will become more important. Competitive bidding for re-
sources mined from federal waters on the continental shelf outside state waters
and the use of sand from foreign commercial sources will lead to substantially
higher, and highly uncertain, future costs. Mechanisms do not currently exist to
contract forward for federal continental shelf resources, and involved federal and
state agencies need to investigate possible arrangements in order to help sponsors
contract for long-term sand commitments. When sand sources for renourishment
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BEA CH NO URISHMENT AND PR O TECTI ON
cannot be identified with certainty, the nourishment program must consist of a
series of individual projects, and each project in the series should then be made
economical.
Project Scope
Beach nourishment projects are often undertaken without due consideration
for their relationship to and impact on other portions of the littoral cells that often
cross political boundaries. Further, most projects encompass only a portion of an
area that can be considered a littoral geographic region or littoral sediment cell;
yet actions within a littoral cell generally affect other areas in the cell and some-
times in adjacent littoral cells. The typical arbitrary proscription of project length
does not adequately account for uncertainties of performance, and all parties need
to recognize this real-world constraint in planning and design. Beach nourish-
ment programs should be planned as part of an overall regional beach manage-
ment plan in which all involved participants undertake appropriate action to
ensure that the process used for planning, design, and approval of projects
achieves this objective.
Economic analyses commonly show that a broad range of potential projects
produces positive and comparable cost-benefit ratios; yet a single project width
that provides maximum net benefits is typically selected as the federal National
Economic Development (NED) plan. However, selection of a plan larger than the
NED plan would provide a safety margin against uncertainty and variability in
project design and performance, often without a significant change in the cost-
benefit ratio while significantly increasing the margin of safety. The federal
government should modify its policies to allow for the selection of a project
larger than the NED plan as long a positive cost-benefit ratio is provided and is
within the financial capability of the local sponsor. A sensitivity analysis of both
the advanced-fill and the design beach should be performed for each prospective
project in order to identify the scope of a more inclusive project that would
reduce the risk of excessive damage.
Borrow Areas
Careful consideration needs to be given to the effects of borrow sites located
within the closure depth (the water depth at which no appreciable movement of
sediment by wave action occurs) of the beach profile or at a shoal site on adjacent
beaches that normally feed the downdrift beaches and are critical to the success of
the nourishment efforts. The impacts of creating a local depression in the sea
bottom on offshore sand movement from the nourished beach and the quality and
quantity of sand are particularly important. Borrowing sands within closure depths
should be done mainly as a sand bypass operation designed to mitigate the effects
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EXECUTIVE SUMMARY
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of any geographical feature or structure that interrupts the littoral movement of
sand.
Timing for Federal Beach Nourishment Projects
The 10- to 15-year-long federal planning process for new beach nourishment
projects and the 5 to 6 years required to activate previously authorized federal
projects add years of uncertainty regarding storm damage, creating burdens for
local sponsors. The federal approval process should be streamlined and delays
minimized through contracting of technical services outside the USACE. Further,
action to remove the institutional constraints that effectively block use of provi-
sions of the Water Resources Development Act of 1992 would enable local
governments to undertake the planning process for authorized projects to reduce
schedule slippage. The federal approval process should be streamlined to permit
more timely decision making and project funding. Federal laws and rules should
be modified to enable federal funding for locally constructed federal projects
upon approval of preconstruction engineering and design by the Assistant Secre-
tary of the Army for Civil Works rather than after a project has been completed.
Commitments for Long-Term Program Maintenance
The long-term financial commitment required to maintain a beach replenish-
ment program effectively, although generally recognized by involved communi-
ties, is not always incorporated into the planning process. The 50-year life cycle
for a typical USACE beach nourishment program is rarely, if ever, paralleled by
similar long-term planning by the public and local project sponsors and may not
be backed by dedicated sand resources for the projected life of the program or for
supplemental renourishments that may be necessitated by severe storms or other
factors. A planned beach nourishment program should be characterized as such
only when long-term planning and commitments to maintain it are in place.
Emergency Maintenance and Contingency Plans
Although severe storms that exceed design levels can create the need for
rapid emergency restoration of a beach or dune system, contingency plans for
emergency repair are not common. Procedural delays caused by locating appro-
priate sources, obtaining permits, and contracting for construction can further
jeopardize endangered buildings. Project sponsors should develop contingency
plans for emergency repair as an integral element of each beach nourishment
program. Emergency-use borrow sites should be identified and the permits ob-
tained and held in reserve. The contingency plan should also establish expedited
procurement procedures to identify and secure the proper dredging equipment.
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Environmental Planning and Monitoring
BEACH NOURISHMENT AND PROTECTION
Most beach nourishment projects are inadequately monitored following con-
struction; monitoring of the physical environment and the performance of the fill
material is often too limited and of insufficient duration to quantify project per-
formance adequately. Consideration of beach nourishment effects on biological
resources has been limited, especially at sand borrow sites. The consequences of
those changes have not been well defined. Beach restoration projects should be
planned so as to avoid significant long-term degradation of the biological re-
sources that are affected by construction activities, with emphasis on monitoring
resources and habitats of greatest concern, including borrow areas. The effects of
dredging and discharging the dredged material should be considered, and, where
feasible, construction projects should incorporate a design that would enhance
biological resources of concern. A monitoring program should be required for all
beach nourishment projects and programs to support these objectives and should
be factored into the life-cycle cost of every project. Monitoring should be appro-
priate to the scope of the project and sufficiently robust to permit evaluation of
changes in the physical and biological conditions. Design of the monitoring
program should recognize how the data will be used in making project-related
decisions, and data should be analyzed and used in a timely manner in decision
making.
Improving the Technical Basis for Decision Making
A better understanding of the physical and biological processes associated
with beach and littoral systems is needed in order to minimize the effects of
uncertainties and to accommodate regional differences in physical and biological
processes. A more complete understanding is also needed of the following factors:
the natural variability of beach profiles and their response to natural processes,
physical processes with respect to closure depths, sand characteristics (i.e., grain
size, shape, density) and their effects on project performance, process-based
cross-shore sediment transport models related to profile changes, and the causes
of erosional hot spots. An intensive research monitoring study for a few large-
scale beach nourishment projects should be undertaken by a third party under
federal sponsorship in order to test the validity of and improve predictive meth-
ods and design assumptions. The costs and economic benefits of projects and
their overall effects on economic development should be assessed.
Design and prediction are constrained by insufficient directional wave and
erosion data needed for verifying the adequacy of design and providing insights
for improving the design methodology. The erosion data that are available are
uneven and of varying usefulness. The USACE should require the collection,
analysis, and dissemination of directional wave data for major beach nourishment
projects in which there is a federal cost share. A uniform, national, reliable data
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EXECUTIVE SUMMARY
11
base on historical erosion rates is needed to improve project design and predic-
tion. The USACE, the National Oceanic and Atmospheric Administration, and
the U.S. Geological Survey should establish the needed data base and standard-
ized rates of erosion and accretion on time scales of a decade for all U.S. shore-
lines that are subject to significant long-term change.
WHAT IS THE APPROPRIATE ROLE OF FIXED SHORE
PROTECTION STRUCTURES?
No device, conventional or unconventional, creates sand in the surf zone.
Any accumulation of sand produced by a structure is at the expense of an adjacent
section of the shore. This fact distinguishes structures and other devices from
beach nourishment, which addresses the basic problem in coastal erosion the
shortage of sand. Traditional structures have a proven track record upon which to
base decisions regarding their suitability. They are capable of providing effective
shore protection and of mitigating the effects of erosion when appropriately
designed, sited, and constructed. However, the use of traditional shore protection
measures without adequate attention to their effects on physical processes within
local littoral cells has contributed to a widespread but technically inaccurate
public perception about the relationship of fixed structures to beach erosion.
Misconceptions about traditional shore protection structures have resulted in pro-
hibitions on their use in a few coastal states, to the detriment of beneficial appli-
cations of the technology. The use of unproven alternatives for shore protection
should be approached cautiously. In particular, the data on which to base the
suitability of nontraditional structures are limited. Evaluation of any beach pro-
tection system is expensive because of the size of any meaningful experiment,
and it is time consuming because of the need for testing under the full range of
climatic conditions.
Fixed Structures
The performance of some beach nourishment projects can be substantially
enhanced by the use of fixed (hard) structures when they are appropriately de-
signed and placed at suitable locations: to anchor project ends, to protect specific
locations (e.g., inlets), to provide a reserve capability to prevent flooding and
wave attack where dunes cannot or do not exist, or to reduce wind-blown losses
to the land. Structure design and associated beach fill need to be carefully planned
and implemented because structures rearrange and control the movement of sand
rather than increase the volume of sand within the littoral system. Agencies with
proscriptive laws, regulations, and management plans for the shore should modify
them to allow the use of fixed structures in conjunction with beach nourishment
projects where project performance can be significantly improved, out-of-project
negative effects are acceptably small or can be mitigated as necessary, and beach
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BEACH NOURISHMENT AND PROTECTION
access or use is not impaired, all with due considerations for costs and environ-
mental impacts. Each fixed structure used in conjunction with a beach nourish-
ment project should be filled to the upper limit of its holding capacity if its
function is to retain sand. When a beach nourishment project is not maintained,
the adverse effects of any structures should be mitigated or the structures re-
moved.
Nontraditional Shore Protection Devices
Nontraditional shore protection devices have been offered or installed as
solutions to shore erosion problems, often without the benefit of objective labora-
tory or field evaluations. In general, these devices are intended to interfere with
wave-driven sand motions and to "trap" in shallow water sand that otherwise
would not be available to the littoral system. Many nontraditional devices have
shown no real capability for shoreline protection over the long term. Some non-
traditional devices that involve large concrete structures placed near the shore
may cause unfavorable conditions that are difficult and expensive to correct. At
the same time, technical innovation should be encouraged in the interest of ad-
vancing the state of practice. A methodology for assessing the suitability and
effectiveness of nontraditional shore protection devices is needed. The USACE
should develop such a methodology in the form of a performance demonstration
specification that any interested agency or private buyer could use. However,
nontraditional devices should not be substituted for beach nourishment where
nourishment is justified without a successful demonstration of the device under
the recommended performance demonstration specifications or a similar proce-
dure developed objectively by qualified engineers acting in a third-party role.
WHAT IS THE ROLE OF BEACH NOURISHMENT IN FLOOD
PROTECTION AND DISASTER ASSISTANCE?
Flood Protection
Beach nourishment projects located seaward of upland buildings reduce
storm damage relative to the level of protection that would exist otherwise. The
damage reduction attributable to a beach nourishment project can be approxi-
mated by using existing risk analysis methodologies. It should be noted, how-
ever, that the level of protection is not absolute because of significant uncertain-
ties about the frequency of storm conditions that may compromise project
performance. The level of protection can be reduced rapidly during a major storm
and is also progressively diminished when a previously nourished beach is not
maintained by subsequent renourishment. In addition to uncertainties that affect
performance, there are uncertainties about the continuing financial means and
political will to continue a renourishment program when not formally required to
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EXECUTIVE SUMMARY
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do so; the long-term availability of beach-quality sediment resources is another
concern. In view of the uncertainties that can affect the level of shore protection,
it is not prudent to lower or eliminate construction or building location standards
that are based on prefill hazard assessments or to alter dune protection setback
requirements in a beach nourishment project benefit area. For the same reasons,
the Federal Emergency Management Agency (FEMA) should not alter (i.e.,
remap) its Flood Insurance Rate Maps to show a widened beach stemming from
a beach nourishment project designated as an "engineered project."
The increased level of protection that is provided by beach nourishment
projects and programs reduces risk and supports a reduction in National Flood
Insurance Program premiums. Unlike the more permanent effects of lowered
construction standards, premiums can be adjusted to accommodate subsequent
changes in the level of protection. A reduction in owner contributions to flood
insurance might be viewed as a subsidy because there are few economic incen-
tives for owners to invest insurance premium savings in further flood hazard
mitigation measures. Yet owners also contribute, primarily through taxes, to the
local cost share of beach nourishment project construction and maintenance.
FEMA should reduce premiums to accommodate decreased risks where an ad-
equately designed, constructed, and maintained beach nourishment program is in
place.
Disaster Assistance
The definition of an "engineered beach" currently used by FEMA to qualify
for payment of sand losses from a beach nourishment project does not, in the
committee's opinion, provide sufficient specific criteria to define the engineering
adequacy of proposed beach restoration projects. The agency's definition of and
requirements for an engineered beach consist of technical criteria, monitoring
requirements, and measures to foster accountability for project performance. The
design level of storm damage reduction should be used as the technical basis for
certification. FEMA should establish a standard risk factor for each major coastal
region and apply this factor when qualifying a beach nourishment project or
determining an engineered beach status. The capacity of an engineered beach to
provide storm protection should be assessed periodically and sources of emer-
gency renourishment material identified in advance. Sediment losses to an engi-
neered beach caused by a storm that results in a presidential declaration of disas-
ter should, in the committee's opinion, be eligible for public assistance
reimbursement to ensure timely restoration of beach or dune dimensions to pro-
tect against subsequent storm damage.
Representative terms from entire chapter:
nourishment projects
