HomeMy WebLinkAbout; ; Shoreline Preservation Strategy San Diego Region; 1993-07-01SHORELINE
PRESERVATION STRATEGY
FOR THE
SAN DIEGO REGIONL
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r JULY 1993M
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San Diego
ASSOCIATION OF
GOVERNMENTS
First Interstate Plaza
401 B Street • Suite 800
San Diego, CA 92101
** This report was financed by Federal funds from the U.S. Army Corps of Engineers,
Hi State funds from the California Department of Boating and Waterways,
and local funds from SANDAG member jurisdictions.
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MEMBER AGENCIES: Cities of Carlsbad, Chula Vista, Coronado, Del Mar, El Cajon, Encinitas, Escondido, Imperial Beach, La Mesa, Lemon Grove,
fP National City, Oceanside, Poway, San Diego, San Marcos, Santee, Solana Beach, Vista, and County of San Diego. ADVISORY/LIAISON
JL MEMBERS: California Department of Transportation, U.S. Department of Defense, San Diego Unified Port District, and Tijuana/Baja California.
Board of Directors
SAN DIEGO ASSOCIATION OF GOVERNMENTS
The San Diego Association of Governments (SANDAG) is a public agency formed voluntarily by
local governments to assure overall area wide planning and coordination for the San Diego region.
Voting members include the incorporated Cities of Carlsbad, Chula Vista, Coronado, Del Mar, El Cajon,
Encinitas, Escondido, Imperial Beach, La Mesa, Lemon Grove, National City, Oceanside,
Poway, San Diego, San Marcos, Santee, Solana Beach, Vista, and the County of San Diego.
Advisory and Liaison members include CALTRANS, U.S. Department of Defense,
San Diego Unified Port District, and Tijuana/Baja California.
CHAIRWOMAN: Hon. Gloria McClellan
VICE CHAIRMAN: Hon. Mike Bixler
SECRETARY-EXECUTIVE DIRECTOR: Kenneth E. Sulzer
CITY OF CARLSBAD
Hon. Bud Lewis, Mayor
(A) Hon. Ann Kulchin, Councilmember
(A) Hon. Julianne Nygaard, Councilmember
CITY OF CHULA VISTA
Hon. Leonard Moore, Councilmember
(A) Hon. Tim Nader, Mayor
CITY OF CORONADO
Hon. Mary Herron, Mayor
(A) Hon. Thomas Smisek, Councilmember
CITY OF DEL MAR
Hon. Elliot Parks, Mayor
(A) Hon. Henry Abarbanel, Councilmember
(A) Hon. Ed Colbert, Councilmember
CITY OF EL CAJON
Hon. Harriet Stockwell, Deputy Mayor
(A) Hon. Mark Lewis, Councilmember
(A) Hon. Richard Ramos, Councilmember
CITY OF ENCINITAS
Hon. Maura Wiegand, Councilmember
(A) Hon. Gail Hano, Deputy Mayor
CITY OF ESCONDIDO
Hon. Jerry Harmon, Mayor
(A) Hon. Lori Holt Pfeiler, Councilmember
CITY OF IMPERIAL BEACH
Hon. Mike Bixler, Mayor
(A) Hon. Marti Goethe, Councilmember
CITY OF LA MESA
Hon. Art Madrid, Mayor
(A) Hon. Barry Jantz, Vice Mayor
(A) Hon. Jay LaSuer, Councilmember
CITY OF LEMON GROVE
Hon. Brian Cochran, Mayor
(A) Hon. Jerome Legerton, Councilmember
CITY OF NATIONAL CITY
Hon. Rosalie Zarate, Councilmember
(A) Hon. Michael Dalla, Vice Mayor
CITY OF OCEANSIDE
Hon. Dick Lyon, Mayor
(A) Hon. Nancy York, Councilmember
CITY OF POWAY
Hon. Don Higginson, Mayor
(A) Hon. Bob Emery, Deputy Mayor
(A) Hon. Mickey Cafagna, Councilmember
CITY OF SAN DIEGO
Hon. Judy McCarty, Councilmember
(A) Hon. Tom Behr, Deputy Mayor
CITY OF SAN MARCOS
Hon. Lee Thibadeau, Mayor
(A) Hon. Mark Loscher, Councilmember
CITY OF SANTEE
Hon. Jack Dale, Mayor
(A) Hon. Hal Ryan, Councilmember
CITY OF SOLANA BEACH
Hon. Marion Dodson, Councilmember
(A) Hon. Paul Tompkins, Deputy Mayor
(A) Hon. Joe Kellejian, Councilmember
CITY OF VISTA
Hon. Gloria E. McClellan, Mayor
(A) Hon. Scott Packard, Councilmember
COUNTY OF SAN DIEGO
Hon. Brian Bilbray, Chairman
(A) Hon. Pam Slater, Vice Chair
(A) Hon. John MacDonald, Supervisor
STATE DEPT. OF TRANSPORTATION
(Advisory Member)
James van Loben Sets, Director
(A) Jesus Garcia, District 11 Director
U.S. DEPARTMENT OF DEFENSE
(Liaison Member)
CAPT. Tom Gunn, CEC, USN
Commanding Officer Southwest Division
Naval Facilities Engineering Command
SAN DIEGO UNIFIED PORT DISTRICT
(Advisory Member)
Jess Van Deventer, Commissioner
TUUANA/BAJA CALIFORNIA
(Advisory Member)
Hon. Hector G. Osuna Jaime
Presidente Municipal de Tijuana
Revised June 16, 1993
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E
E ABSTRACT
TITLE: Shoreline Preservation Strategy for the
San Diego Region
AUTHOR: San Diego Association of Governments
(SANDAG)
SUBJECT: Recommended policies and actions to
preserve and enhance the San Diego
region's shoreline.
DATE: July, 1993
LOCAL PLANNING AGENCY:
NUMBER OF PAGES:
ABSTRACT:
San Diego Association of Governments
401 B Street, Suite 800
San Diego, CA 92101
43
The Shoreline Erosion Committee,
SANDAG staff, and its consultant have
prepared the Shoreline Preservation
Strategy for the San Diego region. It
was adoped by the SANDAG Board of
Directors on July 23, 1993. The
Strategy proposes an extensive beach
building and maintenance program for
the critical shoreline erosion problem
areas in the region, as well as a number
of actions to support this program. The
Strategy contains a comprehensive set of
recommendations on the beach building
program, and on financing and imple-
mentation. The Strategy also includes
three appendices used in its development
and for its implementation.
111
ACKNOWLEDGEMENTS
The Shoreline Preservation Strategy was prepared with guidance from the SANDAG
Shoreline Erosion Committee.
SHORELINE EROSION COMMITTEE
July, 1993
Councilmember Ann Kulchin, Chairwoman Councilmember Abbe Wolfsheimer If
City of Carlsbad City of San Diego
Mayor Mike Bixler, Vice-Chair Councilmember Joe Kellejian ^
City of Imperial Beach City of Solana Beach
Mayor May Herron Supervisor Pam Slater *
City of Coronado County of San Diego HI
Councilmember Rod Franklin Commissioner Jess Van Deventer «
City of Del Mar San Diego Unified Port Commission jj,
Councilmember James Bond Dan Muslin
City of Encinitas U.S. Navy
Deputy Mayor Don Rodee
City of Oceanside _
The important contributions of the former committee members are also acknowledged:
Lou Terrell, City of Del Mar |g
Jan McMillan, City of Del Mar
Lois Ewen, City of Coronado _
John Mahoney, City of Imperial Beach ™
Larry Bagley, City of Oceanside •
Anne Omsted, City of Encinitas
Lieutenant Commander Mike Pind, U.S. Navy m
EX-OFFICIO TECHNICAL ADVISORY MEMBERS
• Dr. Reinhard Flick, California Department of Boating and Waterways
• Sharilyn Sarb, California Coastal Commission
• Dan Gorfain, State Lands Commission
• Bill Fait, State Department of Parks and Recreation
• Stephen Fine, U.S. Army Corps of Engineers (L.A. District)
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The following staff of SANDAG participated in the development of the report:
P|| Stuart Shaffer, Deputy Executive Director
Michael McLaugnlin, Associate Director
p Steve Sachs, Senior Planner, Project Manager
li Marney Cox, Special Services Director
Ken Platt, Assistant Project Manager
f* Christine Egan, Production
Ib Doree Bell, Production
Laura Mays, Graphicsp*
*• In addition, Dr. Craig Everts, Moffat & Nichol Engineers, provided consultant services
for the project.
TABLE OF CONTENTS
I. EXECUTIVE SUMMARY ............................ . 1
H. BACKGROUND .................... . . . : ........ ... 9
m. SHORELINE PROBLEMS AND NEEDS ......... .......... 13
IV. RECOMMENDATIONS ............................. 21
APPENDICES*
I. TECHNICAL INFORMATION USED IN DEVELOPING THE
REVISED DRAFT SHORELINE PRESERVATION STRATEGY
A. IMPLEMENTATION FLOW CHART .................. 3
B. OVERVIEW EVALUATION OF SHORELINE MANAGE-
MENT ALTERNATIVE COSTS AND BENEFITS .......... 7
C. MAPS OF BEACH WIDENING NEEDS IN 1990, 2010,
AND 2040 ................................. 15
D. MAP OF SOUTHERN PORTION OF SILVER STRAND
LITTORAL CELL ............................ 23
E. MAPS OF THE NORTHERN HALF OF THE OCEANSIDE
LITTORAL CELL ............................ 27
F. ESTIMATED VOLUMES, COSTS AND BENEFITS OF
BEACH BUILDING AND MAINTENANCE ............ 35
G. DATA, ASSUMPTIONS, AND EVALUATION METHODS . . 39
*The Appendices are available from SANDAG. Please call (619) 595-5347 to obtain a
copy.
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APPENDICES (cont.)
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li H. PRELIMINARY TECHNICAL REPORT: BEACH WIDTHS
AT SHORES CONDOMINIUMS IN CORONADO 69
P
ll I. PRELIMINARY TECHNICAL REPORT: EVALUATION
OF COASTAL EROSION PROBLEMS IN THE MISSION
f BAY LITTORAL CELL 73
If
H. COMMENTS ON THE DRAFT SHORELINE PRESERVATION
P STRATEGY AND DRAFT RESPONSES
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m. TECHNICAL REPORTS*
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* A. PLANNERS HANDBOOK 1
** B. BEACH COMPOSITION AND PLACEMENT GUIDELINES . . 85fcw
_, C. SEACLIFFS, SETBACKS AND SEAWALLS 97
"These technical reports were not used in preparing the Shoreline Preservation Strategy
and are not part of the objectives, policies, and recommendations in the Strategy. Their
purpose is to provide assistance to local governments, state and federal agencies, and the
private sector in implementing the Strategy.
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LIST OF FIGURES
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Figure 1 Critical Shoreline Erosion Problem Areas 2 "*
Figure 2 Potential Shoreline Management Tactics 11
Figure 3 Estimated Annual Mean Beach Widths, _
Silver Strand Littoral Cell 14 m
Figure 4 Estimated Annual Mean Beach Widths, M
Mission Bay Littoral Cell 15 ^
Figure 5 Estimated Annual Mean Beach Widths, m
Oceanside Littoral Cell (Southern Half) 16 —
Figure 6 San Diego Region Estimated Annual Mean Beach m
Widths Compared to Needs 18 m
Figure 7 Potential Sand Sources for Beach Building and HI
Maintenance, Silver Strand Littoral Cell 23 {j
Figure 8 Potential Sand Sources for Beach Building and Ml
Maintenance, Mission Bay Littoral Cell 25 H)
Figure 9 Potential Sand Sources for Beach Building and pi
Maintenance, Oceanside Littoral Cell (Southern Half) 27 H
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IX
to £P—I San Diego
• ^1 ASSOCIATION OF
P •^J GOVERNMENTS Xo. 94-2
i^ First Interstate Plaza, Suite 800
m 401 B Street
San Diego, California 92101
m (619)595-5300 Fax (619) 595-5305
ADOPTING THE SHORELINE PRESERVATION STRATEGY
FOR THE SAN DIEGO REGION
WHEREAS, the San Diego region's shoreline has, and is expected to continue to
experience serious erosion of its sandy beaches; and
WHEREAS, the region's shoreline is a resource of local, regional, state and national
significance; and
WHEREAS, the region's shoreline is an important part of the region's environment,
economy and overall quality of life; and
WHEREAS, the Shoreline Erosion Committee was established by SANDAG to
coordinate shoreline erosion studies and projects in the region, and to advise the region on
erosion control policies and actions; and
WHEREAS, the Shoreline Erosion Committee has guided the preparation of the
Shoreline Preservation Strategy and recommended that SANDAG adopt it; and
WHEREAS, the Shoreline Preservation Strategy identifies the region's shoreline
erosion problem areas and contains objectives, policies and recommendations which address
these problems; and
WHEREAS, the Strategy is a blueprint for cooperative action by local governments
to implement proactive solutions to these problems which provide significant benefits to the
region's environment and economy; and
WHEREAS, the adoption of the Strategy by SANDAG would make it the region's
official policy on shoreline management and would position the region's local governments and
SANDAG to take maximum advantage of state and federal funding and other opportunities for
implementation action; NOW THEREFORE
BE IT RESOLVED that SANDAG adopts the Shoreline Preservation Strategy for the
San Diego region.
PASSED AND ADOPTED this 23rd day of July, 1993.
CHAIRPERSON
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MEMBER AGENCIES: Cities of Carlsbad, Chula Vista, Coronado, Del Mar, El Cajon, Encanitas, Eacondido, Imperial Beach, La Mesa, Lemon Grove, National City, Oceanside,
Poway, San Diego, San Marcos. Santee. Solana Beach. Vista and County of San Diego.
<"" ADVISORY/LIAISON MEMBERS: California Department of Transportation. U.S. Department of Defense and Tijuana/Baja California.
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I. EXECUTIVE SUMMARY
* I. EXECUTIVE SUMMARYit
IM
"* The Region's Shoreline A Valuable Resource in Trouble
. The shoreline is a valuable asset to the environment and economy of the San Diego region
and the State. It is also considered a resource of national significance. The beaches and
p, seacliffs help define this area's quality of life; when we think of the region's positive
fa image, we most often think of the climate and the shoreline.
,* Long time residents are aware that many of the area's beaches and seacliffs have been
' steadily eroding for the past decade. The Coast of California Study, a six-year, $6 million
scientific evaluation of the San Diego region shoreline conducted by the U.S. Army Corps
p. of Engineers, documented the observations of local people about shoreline erosion and has
^ projected trends of increasing beach loss and property damage in the future.
P> Figure 1 shows the critical shoreline problem areas in the region, including all or portions
te of each of the region's coastal cities: Imperial Beach, Coronado, San Diego, Del Mar,
Solatia Beach, Encinitas, Carlsbad, and Oceanside. The problem areas also include
*•* stretches of shoreline owned and managed by state and federal agencies.
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The Role of the Shoreline Preservation Strategy
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te, The Shoreline Preservation Strategy is the San Diego region's response to the concerns
about erosion voiced by citizens and communities up and down the coast, and by the
** thousands of residents of inland San Diego County who use and enjoy the shoreline.
*•
The unprecedented amount of knowledge gained from the Coast of California Study allows
"" us, for the first time, to be able to measure the extent of the region's current and future
i» shoreline erosion problems and to identify potential solutions to manage these problems.1
The menu of solutions, or tactics, includes: beach building by placing large amounts of
""* sand on eroded beaches; structures to help hold sand in place, such as groin fields;
fc» structures to protect property, such as seawalls and sand berms; and policies and
regulations regarding the use of the shoreline and its development, such as bluff top
** building setbacks. The Shoreline Preservation Strategy sets out regional objectives,
1 The rocky headlands and seacliffs, and the small "pocket" beaches of La Jolla and Point Loma were
not covered in the Coast of California Study. The information and recommendations of the Shoreline
Preservation Strategy do not pertain directly to these areas.
Figure 1
CRITICAL SHORELINE EROSION PROBLEM AREAS
Camp Pendleton
Oceanside
Imperial Beach
MEXICO
Carlsbad
:>
Encinitas
•?
Solana Beach
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to policies, and recommendation for implementing a coordinated list of solutions for each of
the region's shoreline problem areas.
to Who's Involved?
P The Strategy is being put together by the SANDAG Shoreline Erosion Committee, which
Hi is made up primarily of elected officials from the region's coastal jurisdictions. They will
rely on the advice and opinions of the technical advisory members of the Committee
E representing state and federal agencies involved in managing the shoreline, and of the
many individuals and interest groups who will review and comment on preliminary
strategy options — the entire region will be involved in developing and deciding on the
!* Strategy. In order for the Strategy to be effective, everyone in the region will also have
•• to work together to carry it out.
^ Themes
to
The most important idea guiding the Strategy is coordination. Coastal science tells us that
> events in one part of the shoreline will affect beaches and seacliffs up coast and down
™* coast, because sand moves laterally along the shoreline. We now have much of the
^ knowledge needed to coordinate shoreline management actions occurring at different places
and times, and to make sure positive impacts on beaches and seacliffs are reinforced, and
negative ones minimized.
Another very important point about the Shoreline Preservation Strategy is that our role in
preserving and enhancing the region's shoreline will have to be an ongoing, long-range,.
•*» undertaking. This stewardship of the shoreline will involve a number of coordinated
, actions taking place on a continuing schedule over the years. The Shoreline Preservation
Strategy is the action plan for this stewardship. The Strategy looks ahead 20 and 50 years
•P. in the future, to ensure that we can respond to the needs of shoreline structures and public
^ improvements being implemented today, and to the future recreational needs of residents
and visitors.
to Finally, the Strategy proposes an action plan that will require a major financial
commitment from people in our region, as well as funding help from the state and federal
•"" governments.
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Objectives
to The Shoreline Preservation Strategy has four main objectives:
*"" 1. Manage the region's shoreline to provide environmental quality, recreation and
to property protection.
""* 2. Develop and carry out a cost-effective combination of shoreline management tactics
** that will have a positive impact on the region's economy.
3. Develop a program to pay for the shoreline management strategy which equitably
allocates costs throughout the region, and among local, state and federal sources.
4. Obtain commitments to implement and finance the Shoreline Management Strategy.
Policies
The following policies set an overall regional direction for meeting the objectives of the
Strategy.
A. The Strategy should provide a cooperative, coordinated, and long-range preservation
program for the region's shoreline.
B. The Strategy should consider the full range of shoreline management tactics, with
emphasis on beachfilling to preserve and enhance the environmental quality,
recreational capacity, and property protection benefits of the region's shoreline.
C. Structural and mechanical management tactics to stabilize beaches, reduce sand
losses and redistribute sand along the shoreline should be evaluated as complements
to the regional beachfilling program and implemented where they have a positive
impact on cost-effectiveness. Tactics which mimic natural processes should be
preferred when they are equal in cost-effectiveness to other approaches.
D. The Strategy should provide planning estimates of the amount, placement, timing,
cost and sources of beachfill, and describe the process for implementation decisions. .
E. Policies and actions to promote the availability of offshore, coastal and upland
sources of sand for beachfilling and natural beach replenishment should be
developed.
F. The Strategy should provide technical information to assist coordinated and
consistent approaches to local level management tactics, including regulation of
shoreline land use and development, and property protection measures such as
artificial dunes, seawalls and revetments.
G. The Strategy should evaluate local, state and federal policies and regulations and
recommend changes to support the other policies and objectives.
H. The Strategy should be based on the best available scientific data and analysis, and |
on sound engineering principles.
1Recommendations ||
The Shoreline Preservation Strategy recommendations are based on the scientific l|
information from the Coast of California Study and on Engineering and Economic analysis II
of the potential impact of shoreline erosion on coastal property, beach recreation demand
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In and revenues from tourism. The recommendations include proposals for each problem
area, regionwide recommendations which apply to all of the problem areas, and
** implementation, financing and institutional recommendations for carrying out the Strategy.to
BEACH BUILDINGm
I* A beach building and maintenance program is recommended as the primary shoreline
management tactic for each of the problem areas. These problem areas, from south to
f* north, are the shoreline segments for:
• Silver Strand State Beach in the southern part of Coronado, all of Imperial
Beach, and extending about 2'/2 miles south into Mexico;
^ • The entire shoreline from Oceanside Harbor south to and including La Jolla
Shores beach in San Diego.ftf
These beach building and maintenance programs emphasize the nourishment of narrow
beaches with sand to make them wide enough to provide increased property protection and
recreational capacity, and the periodic resupply of sand to these beaches to maintain them.
Potential major sources of sand to support these beach building activities have been
identified at offshore sand bars. In addition, there are a number of "opportunistic" sources
of sand for beach building such as harbor dredging, lagoon habitat enhancement projects,
and water storage reservoirs. The development of the beach building programs will
require detailed engineering, economic and environmental design studies. In addition to
nourishment, the study design for each area should consider a full range of shoreline
management tactics that can support beach widening and improve cost effectiveness.
These tactics include shoreline stabilization, shoreline protection and shoreline develop-
ment regulations.
Planning level analysis done in support of the Shoreline Preservation Strategy illustrates
the general magnitude of activities and costs necessary to implement the most ambitious
beach building and maintenance programs. The initial beach building program would
require the placing of up to 30 million cubic yards of sand on beaches in the problem
areas. The capital cost is estimated in the range of up to $150 million. The annualized
long-term cost of the total beach building and maintenance program for the region is
estimated in the range of up to $5.5 million per year. This annual cost would increase to
up to $12 million per year if it were financed using long-term government bonds. If the
region can take advantage of opportunistic sand sources, these costs could be significantly
reduced. The annual value to the region's economy of the full-scale beach building
program expenditures in 2010 is estimated to be in the range of $8 million in property
protection and $45 million in recreation revenues and benefits. By 2040, the annual values
are estimated to be in the range of $35 million and $190 million, respectively. These cost
estimates include shoreline property protection, recreation and tourist revenue, and local
tax benefits. There are a number of other benefits that are not included, such as protection
of public improvements and private structures. In addition, some costs are not included,
such as impacts on streets from heavy trucks transporting sand from inland sites to
beaches. These planning estimates illustrate the cost-effectiveness of a beach building m
program for the region. The Strategy would be a sound investment for the future of our
economy and environment. m
•M
The beach building program described above, and the associated costs and benefits, are
for a program that builds and maintains all of the region's problem beaches to provide for **
recreational needs and to protect coastal property from damage caused by breaking waves •*
and marine flooding. The design studies, when completed, could well recommend less
extensive programs with significantly lower costs and benefits for two reasons. First, a **
full-scale beach building and maintenance program may not be technically or economically m
feasible in all shoreline areas, due to rates of sand movement offshore or downcoast
Second, in some areas full-scale beach building may not be acceptable due to concerns
about stabilization structures that could be needed, concern about public funding, or the l*
desire of coastal property owners to build seawalls and revetments to protect their land and
buildings. Finally, a phased, or incremental, program could be recommended to reduce
initial costs.
HiThe scope and costs of the beach building programs that are implemented will be decided
by the region's elected officials based on the results of the engineering, economic, and
environmental design studies and public participation and comments. H
FINANCING *
•ITraditional state and federal funding sources should continue to be pursued, but can be ^
counted on to cover only a portion of the total financing needed to carry out the Strategy.
Therefore, a financing program is recommended that emphasizes regional and local m
funding sources, coordinated on a regionwide basis to ensure equity and build support. ||
The local funding program could include: shoreline property owners who will receive
major benefits, both directly due to protection from storm damage and indirectly in terms M
of property value; visitors to the region who use and enjoy the benefits of the shoreline; gf
and all of the region's residents and businesses who benefit substantially through their use
of shoreline beaches and parks, their property values, and economic activity resulting from Ml
beach related tourism. ul
INSTITUTIONAL m
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The cooperative and interjurisdictional nature of the recommended beach building and
maintenance programs, and the significant amount of funds to be raised and expended to Hi
carry them out, will require additional cooperative intergovernmental arrangements among •
the region's local jurisdictions. These arrangements should provide for the involvement
of appropriate state and federal agencies as well as Mexican officials. The purpose of W
these additional arrangements should be to formalize joint decision-making about the **
implementation of the Shoreline Preservation Strategy for each problem area, and to
provide a mechanism for financing. The format of additional arrangements in each P
problem area could range from the designation of a lead agency and the signing of a *
Memorandum of Agreement, to the formation of a joint powers agency or shoreline
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^ authority to carry out implementation. An example of an existing cooperative arrangement
is the BEACH JPA in the Oceanside littoral cell. There may also need to be additional
** arrangements set up to coordinate financing and implementation on a regionwide basis.
|f The most appropriate types of intergovernmental arrangements will depend to some extent
on the financing mechanisms chosen. The institutional arrangements for implementation
»» of the Strategy should therefore be developed concurrently with the financing program.
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The Shoreline Erosion Committee and SANDAG should continue to coordinate shoreline
P preservation activities for the region, including the development of the beach building and
Hi maintenance programs design studies, the regionwide financing program, and the
cooperative arrangements needed to implement the Strategy.
•*• Currently, financing and institutional issues related to the Strategy and other regional needs
are also being considered by SANDAG's Regional Revenues and Open Space Committees.
** These Committees are evaluating Shoreline Preservation needs in combination with other
*» regional open space and sensitive lands needs in a coordinated program to provide
institutional and financial support.
*• IMPLEMENTATION
••»The Shoreline Preservation Strategy identifies the region's shoreline problems and provides
** the policy direction and a process for coordinated decision-making to solve them. There
^ are several key decisions the region will need to make, and several major work tasks
required to provide the information to support those decisions, in order to implement the
*** Strategy once it is approved.
The approval of the Strategy will signal the commitment of the region to pursue
coordinated solutions to our shoreline erosion problems, and will set an overall direction
_ in implementing the solutions. The Strategy necessarily provides for flexibility and
latitude in implementation and financing for a number of good reasons:
•«• Designing the most cost-effective solutions will entail additional field work and
^ engineering and economic analysis. A good example is defining in more detail the
quality and extent of offshore sand resources for beach building.
IP*
^ Detailed environmental studies will be required for any significant modifications to
the shoreline. The impacts to be mitigated range from air pollution and noise from
•* offshore dredging vessels and onshore sand moving equipment, to the effects of
m turbidity on nearshore plant and animal species.
IP Community involvement will need to be a major aspect of implementation. Each
If coastal jurisdiction will need to evaluate the technical options for beach building,
review environmental and economic impacts, and balance local interests and
^ viewpoints so projects can be supported. Of prime importance for many communi-
fe ties will be developing consensus on the appropriate balance between beach
nourishment and replenishment, shoreline stabilization structures such as groins,
structures to protect property such as seawalls, and shoreline development
regulations consistent with regional efforts to control beach erosion. Private sector
initiatives and participation in implementing the strategy should be encouraged.
Finally, the implementation of the Strategy will need to be flexible to respond to
funding and beach building opportunities as they arise. For example, the U.S. Army
Corps of Fjigineers' studies of erosion and storm damage problems in various
communities will provide a significant amount of information for some of the
implementation steps listed below, and will therefore reduce the estimated costs and
increase the quality of information available for making decisions. In addition,
opportunistic sources of sand such as dredged material scheduled to become available
from San Diego Harbor, Batiquitos Lagoon, San Dieguito Lagoon, the Tijuana
Slough and other sources may significantly reduce the costs of beach building
programs and the amount of sand needed from offshore sources.
The following implementation steps illustrate the major decisions and work tasks involved
in implementing the Shoreline Preservation Strategy. Estimated costs and timing are
provided. However, no funding commitments have been secured and specific funding
sources have not been identified. The schedule and costs could change significantly based
on the considerations discussed above.
Decision: Approval/Support of Strategy
(Local Jurisdictions/State &
Federal Agencies)
Work Tasks: Scope of Work and Costs for
Beach Building Design Studies *
Decision: Agreement to Fund and Carry Out
Design Studies (Local Jurisdictions,
State & Federal Agencies)
Work Tasks: Complete Engineering, Economic
and Environmental Design Studies *
Decision: Agreement to Fund and Carry Out
Shoreline Management Program
(Local jurisdictions, State &
Federal Agencies)
Work Tasks: Fund and Implement Projects *
Estimated Estimated
Timing Cost
July-Oct.
1993
FY93-94 $100,000
Calendar
1994
Calendar $2,000,000
1995
Calendar
1996
1996 Up to $5 million/yr.
($12 million/yr. if financed)
These work tasks will most likely consist of several work efforts carried out by different local, state or federal
entities, but coordinated by SANDAG and the Shoreline Erosion Committee. For example, the U.S. Army Corps
of Engineers erosion and storm damage studies, and possible future projects will contribute to all three of the
work tasks.
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II. BACKGROUND
H. BACKGROUND
„ The Region's Shoreline: A Valuable Resource
m The shoreline is a valuable asset to the environment and economy of the San Diego region
^ and the State. It is also considered a resource of national significance. The beaches and
seacliffs help define this area's quality of life; when we think of the region's positive
p, image, we most often think of the climate and the shoreline.
»The Problem
Long time residents are aware that many of the area's beaches and seacliffs have been
steadily eroding for the past decade. The Coast of California Study, a six-year, $6 million
p* scientific evaluation of the San Diego region shoreline conducted by the U.S. Army Corps
^ of Engineers, documented the observations of local people about shoreline erosion and has
projected trends of increasing beach loss and property damage in the future.
p
^ How We Got Where We Are Today
»* Over the past half century, man's actions have been the major influence affecting our
ii shoreline. Through urban development, including water reservoir and dam building, flood
control systems and sand mining, we have cut off the primary natural source of sand for
P our beaches — sediment carried from inland areas by rivers and streams. This sand is also
li the primary buffer protecting seacliffs and coastal development from erosion and storm
damage. At the same time, our activities have made up, and some places even exceeded,
J!* the natural sand sources no longer reaching the shoreline, through the building of "man
•I made" beaches. Most of the sand for this purpose has come from massive and expensive
harbor dredging projects in San Diego Bay and at Oceanside Harbor. While sources of
f* sand as large as these dredging projects will probably never be available in the future, we
to have no choice but to continue our stewardship of the shoreline, or see the gradual
thinning and disappearance of our beaches and increasing destruction of coastal property
!* and development.
How the Shoreline Preservation Strategy Will Helppp t-_-
* The Shoreline Preservation Strategy is the San Diego region's response to the concerns
about erosion voiced by citizen and communities up and down the coast, and by the
thousands of residents of inland San Diego County who use and enjoy the shoreline.
13
The unprecedented amount of knowledge gained from the Coast of California Study allows
us, for the first time, to be able to measure the extent of the region's current and future
shoreline erosion and to identify potential solutions to slow or reverse erosion problems.
The menu of solutions, or tactics, includes: beach building by placing large amounts of
sand on eroded beaches; structures to help hold sand in place, such as groin fields;
structures to protect property, such as seawalls and sand berms; and policies and
regulations regarding the use of the shoreline and its development, such as bluff top
building setbacks. The Shoreline Preservation Strategy will consist of a coordinated list
of tactics for each of the region's shoreline problem areas.
Shoreline Management Tactics
Figure 2 shows the shoreline management tactics considered in developing the San Diego
Region's Shoreline Preservation Strategy. The tactics are grouped into six categories.
They all have the potential to contribute to meeting the two basic goals of the strategy:
1. Preserve and enhance the region's beaches as an environmental and recreational
resource.
2. Protect property and development from storm wave damage and coastal flooding.
Descriptions of all of these tactics and methods that can be used to evaluate their
application to particular reaches (lengths) of shoreline in the region can be found in the
Planner's Handbook in the Appendix.
The first four groups of shoreline management tactics on the chart ~ a) and b) beach
building and maintenance, c) reducing sand losses, and d) redistributing sand along the
coast ~ are primarily regional scale actions aimed directly at increasing the amount of sand
on the region's beaches. They will usually affect all or a significant portion of one of the
region's three littoral cells. (A littoral cell is a self contained shoreline unit in which
actions taken in one reach of the cell will eventually affect the other reaches.)
The last two groups of shoreline management methods on the chart -- e) regulation of
shoreline land use and development, and f) protection of property from storm waves and
flooding -- are primarily local scale methods of dealing with shoreline problems. While
these methods can do little to add sand to the shoreline, they can make the sand
management techniques in the first three groups on the chart more effective.
Ill
III
14 mm
i i t i t i r i t i t t i i r i t i § i t i t i r t
Figure 2
POTENTIAL SHORELINE MANAGEMENT TACTICS
n ft rt
B.
Beach Building and Maintenance. Using Coastal
Sources of Sand From:
• harbor and lagoon dredging
• offshore sand deposits
• undeveloped seacliffs and coastal terraces
Beach Building and Maintenance. Using Upland
Sources of Sand From:
REGIONAL SCALE TACTICS
C. Reduce Sand Losses to:
• submarine canyons
• offshore sand deposits
reservoirs
rivers and streams
grading of development construction sites
other upland sources
D. Redistribute Sand Along the Shoreline bv:
• bypassing (moving sand down coast past
barriers such as harbor jetties)
• backpassing (moving sand up coast, to
recirculate it along its natural direction
of flow down the coast)
• groins (to hold sand in a particular
reach, or length, of the shoreline)
• offshore breakwaters (to minimize the
ability of waves to move sand from a
particular reach; includes research on
kelp beds as well as development of
hard structures)
LOCAL SCALE TACTICS
Regulate Shoreline Land Use and Development by:
• minimizing construction on beaches and in front
of seacliffs
• requiring setbacks from seacliffs, beaches and
low lying coastal areas
• regulation of sand mining
Protect Property from Storm Waves. Flooding and
Seacliff Erosion by:
• artificial dunes
• seawalls and revetments
• blufftop erosion management measures such as
irrigation controls
• beach replenishment
III. SHORELINE PROBLEMS
AND NEEDS
ffl. SHORELINE PROBLEMS AND NEEDS
Present and Future Beach Widths - The Effects of Erosion
^ One of the most important tasks in developing the Shoreline Preservation Strategy involves
, estimating the present and future widths of the region's beaches and comparing them to
the beach widths estimated to be needed for property protection and recreation. These
UP estimates were made possible by the extensive data on the region's shoreline collected by
w the Coast of California Study. Figures 3, 4, and 5 show the estimated annual mean beach
widths for the region's three littoral cells for the years 1990, 2010 and 2040. Littoral cells
m are stretches of shoreline which are physically interconnected. Occurrences in one part
y of a littoral cell will ultimately have an impact on other parts. The estimated beach widths
needed for property protection and recreation are also shown on those maps. Each of the
m. three littoral cells shown in Figures 3, 4, and 5 has been divided into segments, or
^ reaches, designated by dashed horizontal lines. The segments roughly correspond to city
boundaries, and state and federal ownership in some cases.
P^ These three littoral cells are: the Silver Strand cell which extends from south of the
international border to the Zuniga jetty at San Diego Bay and includes the Shorelines of
f* the Cities of Imperial Beach and Coronado; the Mission Bay Cell which includes Ocean,
|i Mission, and Pacific beaches in the City of San Diego; and the southern half of the
Oceanside Cell including shorelines of the Cities of San Diego, Del Mar, Solana Beach,
P Encinitas, Carlsbad and Oceanside. The northern half of the Oceanside cell extends north
li from Oceanside Harbor to Dana Point in Orange County. Data for this area is included
in the appendix.
PI
81 The significant decrease in annual mean beach width estimated for future years in the
Oceanside and Silver Strand littoral cells illustrates the effects of shoreline erosion on the
**- region. The figures show that the most critical areas are located at Imperial Beach and
to South Oceanside and that extensive erosion will also take place in the rest of the Oceanside
Cell, in the southern half of the Silver Strand Cell. The Mission Bay Cell has relatively
^ stable beaches compared to the other littoral cells.
I*
There are several points to take into consideration regarding the estimated beach widths:
* • beach width is defined as the distance between mean sea level and a point delineating
the back of the beach, such as a road, structure or the base of a seacliff;
19
ESTIMATED ANNUAL MEAN BEACH WIDTHS
1990
2010
2040
Estimated annual mean beach width
needed to protect property
and meet recreation demand
FIGURE 3
SILVER STRAND
LITTORAL CELL
Silver StrandState Beach
Border Field
State Park
nm
m
In this area beach width decreased
dramatically for about 1/2 mile in front
of the Coronado Shores Condominiums,
due to construction of the condominiums
on the beach. The condominium property
is partially protected from wave damage
and flooding by a stone revetment.
A supplemental study of this area is
contained in the appendix.
Jn addjtipn,.the appendix contains a larger
map of the southern portion of the cell
depicting the critical erosion areas at
Imperial Beach.
m
ml
| i | r -|i|i|i|if
700' 600' 500' 400' 300' 200' 100'
City Boundary
it
HI
9
*
ESTIMATED ANNUAL MEAN BEACH WIDTHS
1990
2010
2040
Estimated annual mean beach width
needed to protect property
FIGURE 4
MISSION BAY
LITTORAL CELL
5.000
i*
ll
.".'..' J'J'JL'U'J'J'JL/UUUUUWH
500'400'300'200'100'
NOTE: The appendix contains a supplemental evaluation of coastal erosion in the
Mission Bay Cell which provides more detail. Areas in which estimated annual
mean beach width is less than the estimated width needed for protection do
have partial protection from wave damage and flooding from seawalls. The
one exception is the short segment at the northern end of Pacific Beach.
PACIFIC/MISSION
BEACHES
0'
21
ESTIMATED ANNUAL MEAN BEACH WIDTHS
2010 •ww^-
2040 iimimtim
Estimated annual mean beach widthneeded to protect propertyand meet recreation demand
250'
FIGURE 5
OCEANSIDE
LITTORAL CELL
(Southern Half)
SAN
DIEGO
City Boundary
m
m
m'
m
B
Ili • the beach widths shown are annual averages that take into account significant
seasonal fluctuations which usually result in narrower beaches during the winter and
P wider beaches in the summer;i.
• future beach width estimates do not assume any future beach replenishment projects
** but do include the effects of ongoing sand bypassing projects at Oceanside Harbor
4* and Agua Hedionda Lagoon, and of periodic dredging of Mission Bay and beach
replenishment at Ocean and Mission beaches;
^^
** • the widths in the Oceanside Cell assume that currently unprotected seacliffs will
^ continue to retreat at their natural rate, adding sand to the beaches, beach widths will
decrease at an accelerated rate if additional seawalls and revetments are built;
tai
„. Shoreline Erosion Problems and Needs
"*' Figure 6 compares in chart form the data presented in Figures 3, 4, and 5: the estimated
^ annual mean beach widths, averaged for each reach, to the estimated beach width needed
for property protection and to accommodate recreation demand. Reaches where erosion
*" is expected to cause losses of shorefront property and of beach recreation capacity are
•» highlighted. The assumptions, data and methods used in deriving these estimates are
described in the appendix, along with maps showing the comparison of needs and beach
widths.
m It is important to note that the beach width estimates in Figure 6 are averages for the entire
reach. There are variations in beach width within each reach and sometimes they are
— significant. In addition, recent observations of beach widths in many areas indicate that
l_ the maps and data in Figures 3, 4, 5, and 6 are optimistic regarding 1990 beach widths.
fa
p»
23
Figure 6
SAN DIEGO REGION
ESTIMATED ANNUAL MEAN BEACH WIDTHS
COMPARED TO NEEDS
(FEET)
Shoreline Segment (Reach')
Border Field
Imperial Beach
Navy-Cojftifiuaicatioas
Silver Strand
Navy-Amphibious
Coronado
Navy-North Island
ear
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
Estimated'
Actual
Silver Strand Cell
150
100
40
150
110
60
210
190
90
220
210
175
270
265
260
560
570
560
640
680
690
Estimated Totalb
Need For Design
Property Protection
250
250
250
238
238
238
236
236
236
210
210
210
209
209
209
232
232
232
216
216
216
Estimated Total Need to0
Accommodate 100% of
Recreation Demand
26
26
26
119
149
196
ft
m
43
55
73
59
80
110
n|
PI
m
m
1
a. Widths are averaged over the length of each reach.
b. The design width is estimated to protect shorefront property from storms up to and including the estimated 100-year storm.
In some areas, it may not be technically or economically feasible to extend beach width to the extent needed.
c. Assumes 100 square feet of beach per person at peak use. In many areas, there are factors in addition to beach width limiting
the potential to accommodate recreational demand, such as access to the beach, parking and traffic. The last two columns in
this figure are not additive. For example, if the beach were widened from a mean width of 110 feet to 238 feet at Imperial
Beach in 2010, both property protection and recreation needs would be met.
3
24
Figure 6
SAN DIEGO REGION
ESTIMATED ANNUAL MEAN BEACH WIDTHS
COMPARED TO NEEDS
(FEET)
(Continued)
Ocean Beach
Mission & Pacific Beaches
Mission Bay Cell
1990 215
2010 200
2040 185
1990 270
2010 270
2040 270
Oceanside Cell
^ San Diego
SolanS Beach
Carlsbad
P
fc
Camp Pendleton
San Onofre
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
1990
2010
2040
155
130
100
105
75
30
80
70
35
125
115
90
105
90
40
55
40
20
270
290
295
205
230
250
180
140
100
220
220
220
200
200
200
228
228
228
232
232
232
232
232
232
240
240
240
216
216
216
232
232
232
240
240
240
222
222
222
224
224
224
753
914
1159
415
503
638
130
179
256
94
130
189
167
228
325
97
136
195
107
145
207
79
111
161
29
42
63
57
80
120
25
£
1
1
I
I
I
I
I
I
I
I
i
I IV. RECOMMENDATIONS
I
I
I
I
I
I
IV. RECOMMENDATIONS
** The Shoreline Preservation Strategy recommendations are based on the information,
^ evaluation, and policies and objectives presented in the previous sections of the Strategy.
The recommendations include proposals for each littoral cell, regionwide recommendations
which apply to all of the littoral cells, and implementation, financing and institutional
*l recommendations for carrying out the Strategy.
' A beach building and maintenance program is recommended for each of the region's
shoreline problem areas. These programs emphasize the nourishment of narrow beaches
_ with sand to make them wide enough to provide property protection and recreational
L capacity. In addition to nourishment, the design of each beach building and maintenance
program should consider a full range of shoreline management tactics that can support
pi beach widening and make it more cost effective. These tactics include shoreline
j, stabilization, shoreline protection, and shoreline development regulation.
,* It should be noted that full property protection and recreation capacity can never be
j^ guaranteed by beach building, protective structures, or any other combination of tactics.
However, proper design of a management program can provide a fairly high level of
p* confidence that protection and recreation objectives can be met.
ta The specific types and scope of projects for each problem area will be identified in the
** recommended engineering, economic, and environmental design studies. The studies will
IB identify detailed costs, benefits and carryout environmental evaluation requirements.
•» Silver Strand Littoral Cell
ta
1. Design and carry out a cost-effective beach building and maintenance program for
** the southern half of the cell, from Silver Strand State Beach south past the
(to International Border, focusing on the Imperial Beach Shoreline.
E a. The initial volume of sand needed for beach building (increasing the width of
the beach) in this area could be as much as 3 million cubic yards and cost in
the range of up to $15 million.2 Maintaining the increased beach width could
require as much as 90,000 cubic yards of sand per year at an annual cost in
2 The cost estimates in the Shoreline Preservation Strategy are based on an average cost of $5 per
cubic yard of sand. This cost includes design, construction, transportation and placement of sand
including management and contingency.
29
the range of up to $500,000. It is estimated that the economic benefits from
property protection and recreation will exceed the costs of the beach building
and maintenance program within 10 years. Over the long term (20 to 50
years), economic benefits will substantially exceed costs.
b. The major sources of sand for the beach building and maintenance program
include offshore borrow sites near Imperial Beach (estimated 32 million cubic
yards of sand) and near Silver Strand State Beach (estimated 348 million cubic
yards of sand). Other potential sand sources include onshore borrow sites in
the Sweetwater and Tijuana Rivers, habitat enhancement projects in the Tijuana
Estuary, San Diego Bay dredging, and water storage reservoirs. Figure 7
identifies the potential sand sources for this cell.
c. An engineering, economic, and environmental design study for the beach
building and maintenance program should be completed. It should include
consideration of: the two part role of the Tijuana River delta in protecting the
Imperial Beach shoreline from erosion (as a source of sand that replenishes the
beach at Imperial Beach and the rest of the cell, and as a buffer from wave
energy that reduces alongshore transport of sand away from Imperial Beach);
the relationship of beach width to shoreline retreat and amount of beachfill
needed; the relationship of alongshore to offshore sand transport rates and
amount of beachfill needed; variations in annual mean beach width, and in
seasonal changes in beach width within the littoral cell; tactics for dealing with
cobble beaches; the need for groins or offshore breakwaters in particular areas
to regulate the movement of sand up and down coast; the level of property
protection, recreation demand accommodation and beach width desired; the
role of development regulation and shoreline protective devices in reducing the
need for beach building and maintenance in particular areas; recreation, safety,
water use and liability issues related to shoreline management structures; the
issue of compatibility of sand at borrow sites with the needs of nearby beaches;
locations for beachfill placement; effects on surfing conditions; environmental
impacts on water quality, plant and animal species and their habitats; and the
start date for the program. Finally, the program design should be flexible, and
could be incremental, to respond to changing shoreline conditions and new
information.
2. Determine the feasibility and cost effectiveness of capturing sand at the northern end
of the cell near Zuniga jetty, and backpassing it to the southern portion of the cell
where beaches are narrower. Design and carry out a backpassing project if it is a
feasible and cost-effective method of supplementing the beach building and
maintenance program.
3. Provide information from the recommended design study to the Coronado Shores
Property Owners Association to assist their evaluation of potential wave damage and
flooding at the shoreline in front of their property.
30 -
m
POTENTIAL SAND SOURCES FOR
BEACH BUILDING AND MAINTENANCE
SS-1
SS-2
SS-3
Source
(Offshore Imperial Beach)
(Offshore Silver Strand)
(Collection of sand moving
offshore at Zuniga Jetty)
SS-4 (Tijuana River)
SS-5 (Tijuana Estuary Enhancement)
Estimated Volume
in Cubic Yards
31.5 million
347.5 million
120,000/yr.
1.8 million
Unknown
SS-6
SS-7
SS-8
SS-9
(Sweetwater River, east of mapped area .5 million
a. (San Diego Harbor dredging) 0-several 100.000/yr
b. (San Oiego Bay enhancement)
(In the following water storage reservoirs:
Barrett, Loveland, Morena and Upper Otay)
Rodriguez Reservoir in Mexico
Unknown
13.6 million
Unknown
Not shown on this map: development grading sources.
Notes:
•Volumes are rough estimates which should be refined through field
sampling in designing a beach building and maintenance program.
•Source of estimated volumes is the U.S. Army Corps of Engineers Coast
of California Study, Draft State of the Coast Report, October 1,1990 (The
estimates for offshore volumes are based on a 1983 report prepared for
the California State Department of Boating and Waterways titled "Potential
Offshore Sand and Gravel Resources of the Inner Continental Shelf of
Southern California") and the Scripps Institute Center for Coastal Studies
(1991 estimatesof volumes in listed water storage reservoirs, unpublished).
•Volumes of sand neededforafull beach building and maintenance program
in this cell: Initial Fill: 3 million cubic yards, Annual Maintenance: 90,000
cubic yards. The design study proposed for this area could recommend a
less extensive, less costly program.
-.
ft
fa
pi
H
FIGURE 7
SILVER STRAND
LITTORAL CELL
CORONADO (B)
y i
NAVY
AMPHIB. (C)'
Silver Strand >
State Beach (D)
NAVY
COMM. (E)
IMPERIAL
BEACH (F)
Border Field
State Park (G)
SS-6
SS-8
SS-1
SS-4 SS-9
City Boundary
Mission Bay Littoral Cell
1. Evaluate the limiting effects on beach attendance from overcrowding on the beach,
and from parking and access problems, for Ocean, Mission and Pacific Beaches and
determine the feasibility and cost effectiveness of beach building and maintenance
programs to meet recreational needs. Design and carry out a cost-effective beach
building and maintenance program for these beaches if it is determined that
recreational beach use will increase as a result, and that a parking and access
program can be developed to accommodate additional beach users that is acceptable
to local communities and the City of San Diego.
a. The initial volume of sand needed for beach building to accommodate potential
recreational demand in the Mission Bay littoral cell could be between 500,000
and 6.2 million cubic yards3 and cost in the range of up to $31 million.
Beach maintenance could require up to 5,000 cubic yards per year at an annual
cost in the range of up to $25,000. It is highly unlikely that a program of the
larger magnitude would be technically and economically feasible, or that
parking and access could be expanded to accommodate it. The economic
benefits of the increased recreational use accommodated by maximum width
beaches would exceed the costs of the beach building program in the first year
and the long term economic benefits would exceed costs substantially if beach
use increases as assumed.
b. A potential major source of sand for the beach building and maintenance
program is an offshore borrow site off Mission Beach (estimated 192,000,000
cubic yards of sand). Other potential sand sources include an onshore borrow
site in the San Diego River (excluding dog beach), Mission Bay dredging, and
water storage reservoirs. Figure 8 identifies the major sand sources for this
cell.
c. If it is determined appropriate by local communities and the City of San
Diego, an engineering, economic, and environmental design study for a beach
building and maintenance program should be completed. It should include
consideration of: the relationship of beach width to shoreline retreat and
amount of beachfill needed; the relationship of alongshore to offshore sand
transport rates and amount of beachfill needed; variations in annual mean
beach width, and in seasonal changes in beach width within the littoral cell;
strategies for dealing with cobble beaches; the need for groins or offshore
breakwaters in particular areas to regulate the movement of sand up and down
coast; the level of property protection, recreation demand accommodation and
beach width desired; the role of development regulation and shoreline
protective devices in reducing the need for beach building and maintenance in
3 500,000 cubic yards could extend the beach width about 45 yards at Ocean Beach. The 6.2 million
cubic yard program would extend the beach to accommodate estimated peak recreation demand at all the
beaches in the Mission Bay cell.
32
r- POTENTIAL SAND SOURCES FOR
BEACH BUILDING AND MAINTENANCE
Source
MB-1 (Offshore Pacific and Mission Beaches)
MB-2 (Collection of sand moving offshore
at Mission Bay North Jetty)
MB-3 (Mission Bay dredging)
MB-4 (San Diego River, east of mapped area)
MB-5 (In the following water storage reservioirs:
Cuyamaca, Chet Harritt)
Estimated Volume
in Cubic Yards
192 million
11.000/yr.
20.000/yr.
2.8 million
3.4 million
FIGURE 8
MISSION BAY
LITTORAL CELL
Not shown on this map: development grading sources.
Notes:
•Volumes are rough estimates which should be refined through field
sampling in designing a beach building and maintenance program.
•Source of estimated volumes is the U.S. Army Corps of Engineers Coast
of California Study, Draft State of the Coast Report, October 1,1990 (The
estimates for offshore volumes are based on a 1983 report prepared for
the California State Department of Boating and Waterways titled "Potential
Offshore Sand and Gravel Resources of the Inner Continental Shelf of
Southern California") and the Scripps Institute Center for Coastal Studies
(1991 estimatesof volumes in listed waterstorage reservoirs, unpublished).
•Volumes of sand needed for a full beach building and maintenance program
in this cell: Initial Fill: 500,000 to 6.7 million cubic yards. Annual
Maintenance: up to 5,000 cubic yards.
MB-5
PACIFIC/MISSION
BEACHES (B)
33
particular areas; recreation, safety, water use, and liability issues related to
shoreline management structures; the matching of sand at borrow sites with the
needs of nearby beaches; locations for beachfill placement; effects on surfing
conditions; environmental impacts on water quality, plant and animal species
and their habitats; and the start date for the program. Finally, the program
design should be flexible, and could be incremental, to respond to changing
shoreline conditions and new information.
3. Determine the feasibility and cost effectiveness of capturing sand at the southern end
of Mission Beach near the San Diego River jetty and backpassing it to the north and
south where beaches are narrower. Design and carry out a backpassing project if
it is a feasible and cost-effective method of supplementing the beach building and
maintenance program.
Oceanside Littoral Cell
1. Design and carry out a cost-effective beach building and maintenance program for
the southern half of the cell, from Oceanside Harbor south to La Jolla.
a. The initial volume of sand needed for beach building in this area could be as
much as 25 million cubic yards and cost in the range of $126 million.
Maintenance could require as much as 320,000 cubic yards of sand per year
at an annual cost in the range of $1.6 million. It is estimated that the
economic benefits from property protection and recreation will exceed the costs
of the beach building and maintenance program within 2 years. Over the long
term, economic benefits will substantially exceed costs.
b. The major sources of sand for the beach building and maintenance program
include eight offshore borrow sites located along the shoreline from Oceanside
Harbor south to La Jolla (estimated 112 million cubic yards of sand). Other
potential sand sources include onshore borrow sites in various rivers and
coastal terraces, dredge material from the Batiquitos Lagoon enhancement
project, and water storage reservoirs. Figure 9 identifies the major sand
sources for this cell.
c. An engineering, economic, and environmental design study for beach building
and maintenance program should be completed. It should include consider-
ation of: the sand bypassing projects already in effect at Oceanside Harbor
and Agua Hedionda Lagoon; the relationship of beach width to shoreline
retreat and amount of beachfill needed; the relationship of alongshore to
offshore sand transport rates and amount of beachfill needed; variations in
annual mean beach width, and in seasonal changes in beach width within the
littoral cell; strategies for dealing with cobble beaches; the need for groins or
offshore breakwaters in particular areas to regulate the movement of sand up
and down coast; the level of property protection, recreation demand accommo-
dation and beach width desired; the role of development regulation and
34
POTENTIAL SAND SOURCES FOR
BEACH BUILDING AND MAINTENANCE
t*
te
Source
^ SO-1 (Offshore La Jolla)
hi SO-2 (Collection of sand moving down Scripps
and La Jolla submarine canyons)
SO-3 (Offshore Torrey Pines
i SO-4 (Offshore Los Penasuitos Lagoon)
™ SO-5 (Offshore San Dieguito Lagoon)
SO-6 (Offshore San Elijo Lagoon)
^ SO-7 (Offshore Batiquitos Lagoon)
^ SO-8 (Offshore South Oceanside)
™ SO-9 (Offshore North Oceanside)
rf* SO-10 (Collection of sand moving offshore
tj at North Oceanside Harbor Jetty)
£> SO-11 (Los Penasquitos and Soledad Creeks)
SO-12 (Los Penasquitos Lagoon Enhancement)
jgi, SO-13 (San Dieguito Lagoon Enhancement)
Estimated Volume
in Cubic Yards
5 million
30,000/yr.
3.1 million
2.9 million
10.3 million
12.4 million
16.5 million
27.1 million
32.6 million
P"
I.
SO-14 (San Dieguito Terrace, east of mapped area)
SO-15 (San Elijo Lagoon Enhancement)
SO-16 (Batiquitos Lagoon Enhancement)
SO-17 (San Marcos Terrace, east of mapped area)
SO-18 (Agua Hedionda Lagoon Enhancement)
SO-19 (Buena Vista Lagoon Enhancement)
SO-20 (San Luis Rey River, east of mapped area)
SO-21 (Santa Margarita Marsh Enhancement)
SO-22 (Santa Margarita River, east of mapped area)
S}-23 (In the following water storage reservoirs:
Hodges, Henshaw, Wohlford, San Dieguito,
Sutherland)
146,000-440,000/yr.
61 million
Unknown
Unknown
34.8 million
Unknown
2.7-3.7 million
46.5 million
Unknown
Unknown
2.8 million
Unknown
34.8 million
27.5 million
Not shown on this map: development grading sources.
Notes:
•Volumes are rough estimates which should be refined through field
sampling in designing a beach building and maintenance program.
•Source of estimated volumes is the U.S. Army Corps of Engineers Coast
of California Study. Draft State of the Coast Report, October 1,1990 (The
estimates for offshore volumes are based on a 1983 report prepared for
the California State Department of Boating and Waterways titled "Potential
Offshore Sand and Gravel Resources of the Inner Continental Shelf of
Southern California") and the Scripps Institute Center for Coastal Studies
(1991 estimatesof volumes in listed water storage reservoirs, unpublished).
•Volumes of sand needed fora full beach building and maintenance program
in this cell: Initial Fill: 25 million cubic yards. Annual Maintenance: 320,000
cubic yards. The design study proposed for this area could recommend a
less extensive and less costly program.
SO-23
SO-17
FIGURE 9
OCEANSIDE
LITTORAL CELL
SOLANA
BEACH (D)
SO-14
DEL MAR (E)
SAN DIEGO
(F)
City Boundary
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35
shoreline protective devices in reducing the need for beach building and ^
maintenance in particular areas; recreation, safety, water use and liability
issues related to shoreline management structures; the matching of sand at m
borrow sites with the needs of nearby beaches; locations for beachfill M
placement; effects on surfing conditions; environmental impacts on water
quality, plant and animal species and their habitats; and the start date for the pf
program. Finally, the program design should be flexible, and could be H
incremental, to respond to changing shoreline conditions and new information.
^^$
2. Determine the feasibility and cost effectiveness of capturing sand before it is lost *£<
down Scripps and La Jolla Submarine Canyons, and backpassing it to upcoast areas
with narrow beaches. Design and carry out a backpassing project if it is a feasible ft
and cost-effective method of supplementing the beach building and maintenance C
program.
3. Determine the feasibility and cost effectiveness of capturing sand before it moves *!*
offshore of Oceanside Harbor, and bypassing it to downcoast areas with narrow
beaches. Design and carry out a bypassing project if it is a feasible and cost- m
effective method of supplementing the beach building and maintenance program and v
the existing Oceanside Harbor bypassing project. The active movement of sand ^
offshore at Oceanside Harbor should be conclusively determined before this work B
is pursued in the design study. *
REGIONWIDE JJ
1. Develop guidelines for the acceptable composition of beachfill material from all sand —
sources (including innovative sources) considered in the Shoreline Preservation •
Strategy, for use by the appropriate state, federal, and local regulatory and planning ~
agencies. The type, composition and location of placement of dredge material «
should be carefully determined to maximize the amount of sand that gets to beaches. H
2. Develop technical information regarding the issues of shoreline land use and t*
protective structures for use by local jurisdictions. The information should include f|
discussion of the use of setbacks from beaches and seacliffs and beach building over
the use of seawalls and revetments to protect property, and the adverse impacts of Nt
protective structures on beaches and ways to mitigate these impacts. It should be »l
noted that beach building and shore protective structures do not solve bluff failure
problems caused by inland groundwater migration and poorly designed storm drains. fti
a. The technical information should provide for local flexibility in implementation
based on local conditions and existing commitments. Given the wide range of •
local situations, each local jurisdiction should develop its own standards and ll
guidelines consistent with the regional guidelines. There could be provisions
for the use of visually unobtrusive protective structures in combination with pf
beach building where cost effective, and for the use of protective structures It
fm
36
H
^ where the use of setbacks and beach building are infeasible and where
buildings or major public improvements such as roads are in imminent danger.
»•
|» b. Shoreline development issues (new development and protective structures) are
not of equal importance in all jurisdictions, and local conditions and past
*" actions make dealing with shoreline development a unique problem for each
I, jurisdiction. In several communities, for example Coronado and Carlsbad,
shoreline development does not appear to be a major concern because
* protective structures are already in place. Del Mar has a very detailed
to* ordinance and strategy for dealing with shoreline development in place, as does
Oceanside. Solana Beach and Encinitas are very concerned about shoreline
""* development and are actively seeking solutions. The steep seacliffs and
fc narrow beaches in this part of the coast make the problem urgent.
** c. There is a consensus that the best way of dealing with shoreline development
!*• issues is through citywide proactive planning, rather than through case-by-case
decisions on permit applications. There are several potential advantages of the
citywide, proactive approach. It allows the local government, shoreline
«» property owners and the beach-using public to work out tradeoffs on the
benefits and costs of a comprehensive solution. It may also offer some
negotiating opportunities with the Coastal Commission regarding the
•* interpretation of Coastal Act policies which strictly protect the beach and
^ natural seacliff environment at the expense of private property loss.
*" d. The issue of balancing public use and enjoyment of the beach with property
„. protection in addressing shoreline development was a volatile one in every
, workshop where it was discussed. Shoreline property owners are typically,
and understandably, adamantly opposed to the strict implementation of the
— Coastal Act policies which would eventually result in their losing land to
L shoreline erosion. Other members of the public are generally in favor of
protecting the beach and natural shoreline environment as a first priority. A
jpn similar dichotomy exists for the issue of requiring mitigation of the adverse
"L beach impacts of shoreline protective structures. For both of these issues, it
appears that community level resolution will work the best.
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e. Local jurisdictions should use the information in the technical report in their
consideration of shoreline development issues. SANDAG should continue to
assist local jurisdictions through the development of additional technical
information where appropriate.
3. Review harbor, bay and lagoon dredging proposals to ensure that appropriate dredge
material is incorporated in the beach building and maintenance programs recom-
mended for each littoral cell. This action constitutes implementation of die Regional
Dredging policy approved by SANDAG in May, 1991. Evaluation of controls on
sand mining operations should be completed to determine if there could be a positive
37
impact on beaches. Recommendations should be developed as a result of this
evaluation.
4. Review of water storage and reservoir studies and projects to encourage consider-
ation of using beach compatible sediment from these sources as beachfill.
Consideration of water quality impacts on water supply reservoirs and impacts from
transportation of sand to beaches should be taken into account.
5. Determine the feasibility and cost effectiveness of encouraging the placement of
beach compatible material from land development grading at the region's beaches.
Develop regional guidelines for use by local jurisdictions in using this source of sand
in the beach building and maintenance programs recommended for each littoral cell,
if feasible and cost effective.
6. Pursue the evolving legal interpretation of the "public trust doctrine" as it applies to
beach sand for use in implementing recommendations 3, 4, and 5. This concept
could play a significant part in implementing the Shoreline Preservation Strategy.
7. Develop guidelines for the use of temporary methods of protecting shoreline property
from storm damage, such as improved storm warning programs, the use of sand
bags, and the use of temporary sand berms, for use by appropriate state, federal, and
local agencies.
8. Determine the feasibility and cost effectiveness of using beach compatible dredge
material from lagoon and estuary enhancement projects in the region's beach
building and maintenance program, as enhancement projects are planned.
Incorporate sand from lagoon and estuary enhancement projects in the beach building
and maintenance programs recommended for each littoral cell, if feasible and cost
effective.
9. Determine the feasibility and cost effectiveness of transporting sand from reservoirs,
riverbeds (including commercial sandpits) and debris catch basins to the region's
beaches. This evaluation should include The Tijuana River and Rodriguez Reservoir
in Mexico. It should include consideration of impacts of sand removal on public
facilities in floodways (e.g., bridges, utilities) and the costs of transporting sand to
beaches. The cooperation of the County Water Authority and its member agencies
should be obtained. Design and carry out a program of projects which incorporate
these sources of sand in the beach building and maintenance programs recommended
for each littoral cell, if feasible and cost effective.
10. Develop guidelines for land use planning, regulation and development which
encourage the continued contribution of sand to the region's beaches from natural
sources such as seacliffs in undeveloped areas, coastal terraces and ravines, and
upland sources. These guidelines should be coordinated with other land use planning
programs and policies in the region such as open space planning efforts, and should
be used by appropriate state, federal, and local agencies.
38
^ 11. Determine the capacity of local transportation and parking facilities to accommodate
increases in recreational beach use which will be provided for by the beach building
*" and maintenance programs recommended for each littoral cell. Local jurisdictions
«* and state and federal agencies should use this information to identify parking and
access problems and to develop solutions, emphasizing transit.
* 12. Design and carry out a regional shoreline monitoring program to evaluate the
effectiveness of the recommended actions.*»•
««P a. A minimum, low cost monitoring program would involve aerial photo
measurements of beach width annually or semi-annually. Also, the existing
*"" wave measuring gauges off the region's coast should be retained by the state
*"? and federal agencies operating them.
b. A more effective monitoring program with more frequent beach width
m measurements and periodic measurements of littoral zone beach profiles should
be pursued. Both innovative, high technology approaches such as satellite
archieves; and simple, low technology methods such as tape measurement of
beach widths by city staff or citizen volunteers should be considered in
^ supplementing the basic monitoring program.
*"* c. More detailed monitoring efforts may be included in the design of the beach
^ building and maintenance programs developed for each littoral cell, and for
specific projects.
M 13. An annual "State of the Region's Beaches" report should be prepared by SANDAG
L^ to describe progress made in implementing the Strategy and identify problem areas
™ that need emphasis.
.m FINANCING
*~ (See institutional recommendations for a discussion of responsibilities.)
V 1. Traditional state and federal funding sources such as the State Department of Boating
«*• and Waterways, the Coastal Conservancy and State Bond Act grants and loans, and
^ federal assistance through the U.S. Army Corps of Engineers should continue to be
pursued by organizations implementing the Shoreline Preservation Strategy. Special
F sources of state and federal funds that may become available from time to time
III through agencies such as the California Coastal Commission, State Lands Com-
mission, the federal Environmental Protection Agency, and the National Oceanic and
*** Atmospheric Administration should also be pursued. In most instances, these funds
* will have to be legislatively initiated. It is anticipated that state and federal funds
will cover only a portion of the total financing needs.
H| 2. The financing program should be developed on a regional basis to ensure equity and
to build understanding and support. It should be selected by the region's elected
*39
p»
»
officials based on the design studies and public participation and comment. The
cooperation and needs of involved state and federal agencies should be considered
in financing decisions. It should take into account the cost incurred by cities to
provide beach related functions such as; lifeguard services, maintenance, insurance,
etc.
3. The financing program should be designed to consider the high front end costs of
beach building and should be flexible to allow for the setting of priorities where
program needs exceed funds available, and to incorporate new sources of financing
as they become available. It should recognize that a major portion of the needed
funds will have to come from local and regional sources.
4. Shoreline property in the areas of the region where the beach building and
maintenance programs are focused will receive major benefits from the program
results, both directly from property protection and indirectly in terms of property
value. A financing mechanism which includes shoreline property for an equitable
share of the needed funds should be considered.
a. One appropriate financing mechanism to obtain funds from shoreline property
is an assessment district.
b. State and federal agencies owning shoreline property should contribute funds
for the beach building and maintenance program in proportion to their benefits.
5. It is estimated that visitors to San Diego County account for about 20% of the
region's beach users. A financing mechanism which collects an equitable share of
the needed funds from visitors should be considered. Transient occupancy taxes are
one source for these funds.
6. San Diego County residents and businesses benefit substantially from living close to
the region's shoreline. They benefit directly from their use and enjoyment of
beaches and parks, and indirectly in terms of property value and economic activity.
A financing mechanism which targets residents for an equitable share of funds should
be considered.
a. There are several potential financing mechanisms that can be used to collect
funds from residents. They include assessment district(s), a parcel tax, an
increase in the local sales tax and an increase in the property tax.
b. A regional impact fee on new development for its fair share of costs could be
considered.
c. Creation of a utility by local agencies which could charge fees for shore and
beach services could be considered. This innovative financing method has
been used by several local agencies in the U.S.
40
»
p*
7. Financing of the Shoreline Preservation Strategy should be coordinated with other
Open Space and Natural Resource Financing needs and programs through the
Regional Growth Management Strategy being developed by SANDAG. The
SANDAG Regional Revenues Advisory Committee and Open Space Citizens
Advisory Committee should include financing of the Shoreline Preservation Strategy
in their work.
8. The first priority for use of public funds should be for protection, preservation and
enhancement of publicly owned resources.
INSTITUTIONAL
1. The Shoreline Erosion Committee and SANDAG should continue to coordinate
shoreline preservation activities for the region, including the design studies and
implementation of the beach building and maintenance programs for the region's
shoreline problem areas.
2. Financing and the cooperative institutional arrangements that may be needed to
implement the Strategy should be developed through the cooperative work of the
SANDAG Open Space Citizens Advisory Committee, Regional Revenues Advisory
Committee, and the Shoreline Erosion Committee.
3. Local jurisdictions and state and federal agencies will be responsible for a number
of implementation actions, as specified in the recommendations. Some of these
actions will need to be implemented locally through amendments to Local Coastal
Plans (LCP's), General Plans, and ordinances. Local corollaries to the first three
regional objectives in the Strategy should be incorporated into LCP land use plans.
4. The interjurisdictional nature of the recommended beach building and maintenance
programs, and the significant amount of funds to be raised and expended to carry
these programs out, could require additional cooperative intergovernmental arrange-
ments for implementation.
a. The purpose of additional arrangements would be to formalize joint decision
making about the implementation of the Shoreline Preservation Strategy, and
to provide a mechanism for financing.
b. The arrangements should provide for the involvement of appropriate state and
federal agencies as well as Mexican officials.
c. The format of additional arrangements could range from the designation of a
lead agency and the signing of a Memorandum of Agreement, to the formation
of a joint powers agency or shoreline authority to carry out implementation.
An example is the BEACH JPA in the Oceanside littoral cell. There may also
need to be additional arrangements set up to coordinate financing and
implementation on a regionwide basis.
d. The most appropriate types of intergovernmental arrangements will depend to
some extent on the financing mechanisms chosen. The institutional arrange-
ments for implementation of the Strategy should therefore be developed
concurrently with the financing program.
IMPLEMENTATION
1. The implementation of the Shoreline Preservation Strategy should provide for
flexibility and latitude to accommodate the following:
a. Additional field work and engineering and economic analysis.
b. Detailed environmental studies.
c. Community involvement. Of prime importance for many communities will be
developing consensus on the appropriate balance between beach nourishment
and replenishment, shoreline stabilization structures such as groins, structures
to protect property such as seawalls, shoreline development regulations, and
impacts on upcoast and downcoast shorelines.
d. Funding and beach building opportunities that may arise. For example, the
U.S. Army Corps of Engineers' studies of erosion and storm damage problems
in various communities will provide a significant amount of information
applicable to implementation and may lead to federal funding opportunities.
Opportunistic sources of sand that may become available could reduce program
costs.
2. The following implementation steps, and timing and cost estimates, illustrate the
major decisions and work tasks involved in implementing the Shoreline Preservation
Strategy:
Implementation Step Timing Cost
a. Approval/Support of Strategy July-Oct.
(Local Jurisdictions/State & 1993
Federal Agencies)
b. Scope of Work and Costs for FY93-94 $100,000
Beach Building Design Studies *
c. Agreement to Fund and Carry Out Calendar
Design Studies (Local Jurisdictions, 1994
State & Federal Agencies)
d. Complete Engineering, Economic Calendar $2,000,000
and Environmental Design Studies * 1995
42
e. Agreement to Fund and Carry Out Calendar
Shoreline Management Program 1996
p (Local jurisdictions, State &
i Federal Agencies)
p f. Fund and Implement Projects * 1996 Up to $5 million/year
y ($12 million/year
if financed)
IQ, * These work tasks will most likely consist of several work efforts carried out by
different local, state or federal entities, but coordinated by SANDAG and the
Shoreline Erosion Committee. For example, the U.S. Army Corps of Engineers
erosion and storm damage studies, and possible future projects will contribute to
all three of the work tasks.
A flowchart, describing in more detail the tasks and decisions described above, and
their relationship, is contained in the Appendix.
m
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43