HomeMy WebLinkAboutPCD/GPC 91-01; Carlsbad Boulevard Seawall; Planning Comm Determ/Gen Plan Consis (PCD/GPC) (2)STATE OF CALIFORNIA—THE RESOURCES AGENCY PETE WILSON, Governor
CALIFORNIA COASTAL COMMISSION
SAM DIEGO COAST AREA
3111 CAMINO DEL RIO NORTH, SUITE 200
SAN DIEGO, CA 92)08-1725
(619) 521-8036
Filed:
49th Day:
180th Day:
Staff:
Staff Report:
Hearing Date:
August 19, 1994
Waived
February 15, 1995
BP-SD
October 26, 1994
November 15-18, 1994
STAFF REPORT: CONSENT CALENDAR
Application No.: 6-94-91
Applicant: City of Carlsbad Agent: Pat Entezari
Description:Construction of approximately a 3,185-ft. long seawall (2,800
feet of cantilevered steel sheet pile seawall and one
385-ft-long revetment) with three access ramps and two stairways
for beach access and other public facilities. The sheet pile
seawall consists of a concrete cap and toe stone with the
exposed portion of the wall proposed at 3.5' above beach level.
The revetment is proposed at the north end of the project area
and would tie into an existing jetty.
Zoning
Plan Designation
Open Space
Open Space
Site:Carlsbad Boulevard from Agua Hedionda bridge to 200 feet south
of SDG&E's warm water jetty, Carlsbad, APN 210-01-13-33
STAFF NOTES: On November 12, 1991 the Commission approved what is basically
the above project. In its action to limit beach encroachment on this heavily
used beach from the shoreline protective device proposed at that time, the
Commission deleted the proposed south revetment and required its redesign to a
vertical seawall. The above project reflects the Commission's action.
However, the permit expired and the approved project is before the Commission
as a new application. Staff is recommending approval of the project subject
to the prior special conditions the Commission approved.
Summary of Staff's Preliminary Recommendation:
Staff is recommending approval of the proposed development subject to a number
of special conditions regarding project timing and staging; design and
materials, future maintenance, construction and staging concerns, assumption
of risk, State Lands Commission review, State Department of Parks and
Recreation review, and an assertion of public rights.
Substantive File Documents:Certified Carlsbad Local Coastal Program
Mello II segment, Feasibility Study, Carlsbad
Boulevard Shore Protection, Carlsbad Beach State
Park - Area 3 (August 1988); Design Memorandum,
Carlsbad Boulevard Shore Protection, City of
Carlsbad (August 1993); COP #6-91-60
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The staff recommends the Commission adopt the following resolution:
I. Approval with Conditions.
The Commission hereby grants a permit for the proposed development, subject to
the conditions below, on the grounds that the development, as conditioned,
will be in conformity with the adopted Local Coastal Program, and will not
have any significant adverse impacts on the environment within the meaning of
the California Environmental Quality Act.
II. Special Conditions.
The permit is subject to the following conditions:
1. Storm Design. Prior to the issuance of the coastal development
permit, the applicants shall submit certification by a registered civil
engineer, acceptable to the Executive Director, that the approved shoreline
protective device is designed to withstand storms comparable to the winter
storms of 1982-83. Said certification shall be subject to the review and
written approval of the Executive Director.
Within 60 days following the completion of the project, the applicants shall
submit certification by a registered civil engineer, acceptable to the
Executive Director, verifying that the shoreline protective work has been
constructed in conformance with the final approved plans for the project.
2. Maintenance Activities/Future Alterations. Maintenance of the
protective works shall be the responsibility of the applicant, unless
responsibility is assumed by the State Department of Parks and Recreation.
Any change in the design of the project or future additions/reinforcement of
the seawall will require a coastal development permit. If after inspection,
it is apparent that repair or maintenance is necessary, the applicant(s) shall
contact the Commission office to determine whether permits are necessary. The
applicants shall also be responsible for the removal of debris that is
deposited on the beach or in the water during or after construction of the
shoreline protective device or as a result of the failure of the shoreline
protective device.
3. Construction Materials. Disturbance to sand and intertidal areas
shall be minimized. Beach sand excavated shall be redeposited on the beach.
Local sand or cobbles shall not be used for backfill or construction material.
4. Construction Easement. Prior to the issuance of the coastal
development permit, the applicant shall submit an executed construction
easement from the State Department of Parks and Recreation which indicates
their approval of the applicant's proposed work, the construction schedule and
construction access and staging plans as they affect State Parks property. If
the final easement is not consistent with the Commission's approval, an
amendment would be required to reconcile any proposed work.
5. Hold Harmless Agreement. Prior to the issuance of the coastal
development permit, the applicant shall submit a signed document which shall
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indemnify and hold harmless the California Coastal Commission, its officers,
agents and employees against any and all claims, demands, damages, costs,
expenses of liability arising out of the acquisition, design, construction,
operation, maintenance, existence, or failure of the permitted project.
6. Construction Access and Staging Areas/Project Timing. Prior to the
issuance of the coastal development permit, the applicant shall submit to the
Executive Director for review and written approval, a construction schedule
and construction access and staging plans. The Executive Director shall
review the submitted documents to insure: a) that construction activities are
prohibited between Memorial Day and Labor Day of any year; b) that all
construction staging, storage of materials, and other construction related
activities in support of the project shall occur only within the two (2) areas
immediately north and south of the SDG&E warm water outlet jetty and be
appropriately fenced and protected for public safety; and, c) that two-way
traffic, north and south, will be available on Carlsbad Boulevard at all times
during construction.
7. State Lands Commission Review. Prior to issuance of the coastal
development permit, the applicant shall obtain a written determination from
the State Lands Commission that:
a. No State lands are involved in the development; or,
b. State lands are involved in the development, and all permits
required by the State Lands Commission have been obtained; or,
c. State lands may be involved in the development, but pending a
final determination, an agreement has been made with the State
Lands Commission for the project to proceed without prejudice to
that determination.
IV. FINDINGS AND DECLARATIONS.
The Commission finds and declares as follows:
1. Project Description. The applicant proposes the construction of an
approximately 3,185-ft. long seawall (2,800 feet of cantilevered steel sheet
pile seawall and one 385-ft-long revetment) with three access ramps and two
stairways for beach access and other public facilities. The sheet pile
seawall consists of a concrete cap and toe stone with the exposed portion of
the wall proposed at 3.5' above beach level. The revetment is proposed at the
north end of the project area and would tie into an existing jetty.
Currently, beach access is unrestricted along the entire length of the subject
area. The project proposes three access ramps and two stairways through it to
provide beach, handicap, and emergency access. Other public improvements
proposed landward of the vertical wall include benches and planters, a
sidewalk, and lifeguard towers.
The primary purpose of the shore protection is to protect Carlsbad Boulevard,
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the major north/south coastal route in the area, and existing and proposed
improvements located therein, which include parking, utilities, and a bicycle
lane. Widened in 1988-89 to a four lane arterial, Carlsbad Boulevard runs
adjacent to the coast, becoming Old Highway 101 to the south where Carlsbad
borders Encinitas. In the project area, it is bounded on the east by Agua
Hedionda Lagoon and on the west by the Pacific Ocean. In addition to
providing north/south access, it contains the majority of the utility lines
which serve this portion of the City. This area of the roadway has been
historically subject to erosion and damage during high tides and major
storms. The City proposes the shoreline protection to protect these
improvements, as well as existing utilities in the roadway, and to reduce
maintenance costs. Alternatives, such as relocating the roadway to the east,
proved infeasible due to the existence of development and the cost of
acquiring additional right-of-way area.
The project lies within the plan area of the certified Carlsbad Local Coastal
Program Mello II segment. This segment of the LCP was certified by the
Commission in 1980; the City is currently preparing the necessary documents to
seek effective certification of the LCP. Pursuant to Section 30519(c),
projects within this plan area are usually reviewed for their consistency with
the certified LCP. However, the project site is located on the beach which
fronts the ocean and is subject to public trust. It was included within the
Commission's original jurisdiction area wherein projects are reviewed for
consistency with the Chapter 3 policies of the Coastal Act.
Existing Conditions
The subject area is generally situated near the middle of the Oceanside
littoral cell. The sand levels vary seasonally and are mostly removed during
high tides and storms during the winter. While generally "sandstarved", the
coastline of Carlsbad manages to maintain a finite beach width, apparently due
to the abundance of gravel and cobbles in the area. The subject area also
receives sand nourishment every two to three years from dredging of the
lagoon. However, erosion of the beach and damage to the roadway due to high
tides and storm waves occurs on a periodic basis. Since 1982-83, the maximum
recorded erosion in the subject area along the west side of Carlsbad Boulevard
during a storm was down to approximate elevation +6 feet Mean Sea Level
(msl). (Further references to elevations in this report will use the mean sea
level datum; additionally, it should be understood that these references
represent approximate elevations).
Going from north to south, the subject area extends for 3,185 linear feet and
covers the area from the jetties at the entrance to Agua Hedionda lagoon to
residential development along Tierra del Oro Street in the City of Carlsbad.
The project begins near the south side of the ocean entrance jetty to the
outer basin of Agua Hedionda Lagoon. An existing 2:1 fill slope would serve
as the base for the north revetment; the slope extends down from the sidewalk
along the western edge of Carlsbad Boulevard to the beach. The top of the
slope ranges from +22 at the north end near the jetty to +15 at the southern
extreme of the proposed revetment; the toe of the slope daylights into the
beach at +4. The upper portion of the slope has been eroded and damaged to
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near vertical; the middle and lower portions of the slope are partially
protected by dumped rock and rubble (unengineered, average size 400-500
pounds). At and below beach grade, buried rock and rubble are also present.
The beach in this area is historically thin and narrow. Almost every year the
winter storms strip away the thin layer of sand, leaving a variegated layer of
gravel and cobbles over the underlying sands and gravels.
Carlsbad Boulevard levels out just beyond the southern limit of the proposed
north revetment and gently undulates for the next 2,300 feet. The beach area
along the west side of the sidewalk is typically 150 to 200 feet wide to the
ordinary daily high water line; it narrows at the north end near the lagoon
jetty and widens at the south end near the jetty for the San Diego Gas and
Electric Company's (SDG&E) warm water outlet. Typically, there is a
relatively level, sandy surface about 40 to 60 feet wide adjacent to and west
of the sidewalk, which is underlain by a 6 to 10 foot high berm that is
generally composed of gravel and cobbles. This area slopes down gently
towards the ordinary high water mark and then gently offshore. Existing
unengineered rock extends out from the sidewalk to the end of the SDG&E warm
water outlet jetty and protects a relatively sandy pad at the south end of
this area.
Carlsbad Boulevard has a low elevation here, +13 on the south side of the warm
water outlet, and then begins to climb in elevation to +35 to the south.
SDG&E's Encina Power Plant is located on the inland side of Carlsbad Boulevard
in this area. The beach between the south jetty for the outlet and a rock
groin along the existing SDG&E fuel intake line is currently wide (200 feet or
more) and sandy. The warm water outlet jetties and the fuel intake groin line
appear to maintain the beach sand in this area, even during storms, although
shoreline protection is proposed in this area as well. The SDG&E warm water
outlet jetty, where heated process water is returned to the sea, is protected
by dumped rock and is fenced-off from public use.
In the southern part of the subject area, road fill resulting from the 1988-89
widening of Carlsbad Boulevard is present between Stations 52 to 56. The top
of this fill slope along the west edge of the sidewalk ranges from +20 at
Station 52 to elevation +35 at Station 56. The road fill slopes down from the
sidewalk at 2:1 and toes into existing sand/cobbles beach (depending on
season) at +8 to +12. The slope is currently covered with sparse vegetation
and weeds. There is a level, sandy portion of the beach at the toe of the
road fill, adjacent to and south of the fuel intake line groin, that is
partially protected by dumped rock; it extends out from the groin towards the
fill. The beach narrows to the south of this sandy area beyond Station 53.
Bedrock is exposed at the base of the coastal bluff at the south end of the
fill (Station 56 at an elevation of +12).
The proposed shoreline protective devices consist of a vertical seawall and a
revetment. Both proposals are discussed below.
The Proposed Seawall
The proposed 2,800 foot long steel sheet pile seawall is an anchored,
vertical-driven, treated steel sheet pile wall with a reinforced concrete
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cap. The wall is proposed to be driven down into the sand/cobble/gravel
subsurface to a depth of -13 feet to stablilize it (no bedrock to tie-into in
this area). A 6 to 10 foot wide berm lies immediately adjacent to the
proposed wall, which then feathers down to the 150 to 200 foot wide sandy
beach. The sheet pile seawall consists of a concrete cap and wave deflector
with its top ranging from +16 to +19; the exposed portion of the wall is
proposed at 4 feet above beach grade. The concrete cap is proposed to extend
to elevation +3 feet (7 to 9 feet below natural beach level). The wall will
be sandstone color and include a continuous public art motif.
For the majority of its length, the vertical wall is proposed within the
roadway's existing right-of-way, abutting the west (seaward) edge of the
sidewalk. However, the wall extends seaward onto sandy beach and State
Department of Parks and Recreation property to protect the proposed stairways
(11 feet) and ramps (21 feet). The City and the Parks Department are
preparing a construction easement for the project.
According to the coastal engineering study, the low spots in the wall would be
overtopped during design storm and scour conditions. For anticipated extreme
storm and scour conditions, most of the wall will be overtopped and may result
in some damage to the wall and the sidewalk by causing it to "deflect" into
the sidewalk. The wall is designed to not fail during scour to -3 feet and a
seismic event with ground motions of up to .2 g. It is anticipated that the
toe stone and steel sheeting would only be exposed during the worst high tide
and storm conditions.
The proposed project has been designed to protect the roadway, road fill and
utilities for 75 years. The seawall has also been designed to have a maximum
deflection of 1 inch at the top of the wall. To maintain acceptable wall
deflections throughout the 75-year life of the roadway, the wall must be
protected from scour beyond +3. These criteria have driven both the need for
and size of the protection.
To prevent scour below +3, the wall has been designed with toe protection
starting at +6 at the wall, which goes down to -1 to -2 msl on a 5 to 1
slope. At the lower elevation, this protection will be approximately 15'
seaward of the wall. Under normal conditions, the sand elevation along this
section of beach is approximately +10, and there is no record of the beach
scouring lower than about +7. The toe protection should be exposed only
during extreme storm conditions, during which time it should protect the wall
from unacceptable deflections.
The toe protection is being provided for extreme events. The possibility of
requiring this project to add toe protection only after the beach level eroded
to a pre-determined level (as has been proposed in Del Mar), has been
considered, but rejected based on two major drawbacks. First, it would
provide for two periods when the beach will be seriously disrupted and beach
access would be restricted - once for the wall and later for the toe
protection. Second, it would be difficult to develop a safe "trigger" for
adding the toe protection. Several recent storms have scoured the beach to
within 4 feet of the critical depth. This may be well within the range of
scour for an extreme storm event.
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The Proposed Revetment
In addition to the seawall, construction of a rock revetment is proposed. The
north revetment (3851 long, 50' wide, 19' wide crown, top ranging from +17 -
+20) would be placed in an area where rip-rap of varying size has been placed
on an on-going basis for a number of years; it would tie into the existing
jetty and extend down in front of the sheet pile wall at its north end.
Project plans call for the north revetment to be built-over existing dumped
rock on the slope, using existing unengineered rip-rap as a base. The
proposed revetment would extend seaward onto portions of what is now sandy
beach. The relative encroachment of the revetment is addressed in Section #3.
Construction of the revetment involves the removal of a portion of the
existing toe of slope and beach profile and placement of three layers of
material to form the revetment. The three layers would be: (a) a filter
cloth (b) a quarry, or understone layer and (c) a double layer of 3-ton stone
rip-rap. The revetment would be constructed at a 1.5:1 slope; the most
seaward portion of each (toe) to be buried beneath the sand at -3.
2. Shoreline Protection. Policy 4-3 of the certified Mello II LUP
states:
Revetments, breakwaters, groins, harbor channels, seawalls,
cliff retaining walls, and other such construction that alters natural
shoreline processes shall be permitted when required to serve
coastal-dependent uses or to protect existing structures or public beaches
in danger from erosion, and when designed to eliminate or mitigate adverse
impacts on local shoreline sand supply. As a condition of approval,
permitted shoreline structures may be required to replenish the beach with
imported sand...
In addition, the above language is mirrored in the Coastal Development Overlay
(C-D) zone, an implementing measure included in the certified LCP pursuant to
the policies of Chapter 3 of the Coastal Act regarding public access,
shoreline processes and geological stability.
The subject project is proposed to protect Carlsbad Boulevard and its existing
and proposed improvements from damage and destruction due to wave attack. The
Design Memorandum prepared for the project states:
Carlsbad Boulevard in the area of Carlsbad State Beach between the inlet
and outlet jetties for Agua Hedionda Lagoon is at a relatively low
elevation and as such is subject to wave attack and high tides. This is a
heavily used beach area and Carlsbad Boulevard is a main north-south
traffic roadway...If its improvements are not protected, considerable
repair and maintenance costs may be realized, as well as possible loss of
utility services...North-south through traffic would be disrupted and
vehicular access to and parking for a considerable length of beach may be
lost for extended periods of time.
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The report concludes that: "In the event of severe storm conditions and
accompanying high waves, it is apparent that the existing roadway and
utilities along this stretch of beach are in danger from wave attack".
While that danger of wave attack in the area is not at present great due to
recent beach nourishment of the area, the Commission notes that the threat to
Carlsbad Boulevard from wave attack is continuous on an infrequent but
periodic basis. Both the City of Carlsbad and the Department of Parks and
Recreation have documented damage to the roadway from wave attack,
particularly in the 1982-83 and 1988 storms where storm surges coupled with
high tides resulted in overtopping and structural damage to the road. The
areas where slope and street repair have been required do not cover the full
3,185 foot stretch of proposed seawall; yet, they occur often enough to merit
the construction of shoreline protection for an existing and important coastal
access route. If such protection was to be constructed only in the
intermittent locations where damage from wave attack has already occurred, the
result would be a series of seawalls. Ultimately, a patchwork of devices
might be constructed which could have a greater impact on public access,
shoreline processes, and the scenic resources of the area than the proposed
seawall.
Instead, the applicant has proposed construction of a seawall with a
comprehensive approach to the present and anticipated erosion problems. While
the proposed seawall will also have an adverse effect on access, shoreline
processes, and the scenic resources of the area, the applicant, on whole, has
attempted to minimize these impacts and, where possible, mitigate them.
It has long been understood that all designs of shoreline protection, when
placed in an intertidal area, adversely affect shoreline processes and beach
profiles. The impacts of shoreline structures on the beach is a persistent
subject of controversy within the discipline of coastal engineering and
particularly between coastal engineers and marine geologists. Much of the
debate focuses on whether seawalls or other factors (such as the rise in sea
level) are the primary cause of shoreline retreat. This debate tends to
obscure the distinction between the long-term trends of the shoreline, and the
effects of seawalls on those long-term trends, and the shorter term effects
that might not be permanent but may significantly alter the width and utility
of a beach over the course of a year. The site-specific impacts of the
proposed seawall will be addressed in the following paragraphs.
Three access ramps are proposed through the project to provide vertical access
from Carlsbad Boulevard to the beach. The primary purpose of these ramps is
for lifeguard vehicle access to the beach and for safety; a secondary use is
for handicap access. Besides providing access, these ramps would incorporate
other public improvements (i.e., planters, benches, handicap viewing areas,
lifeguard towers) to provide beach-related amenities for those persons that
cannot or may not want to use the beach itself, but still enjoy the atmosphere
and the view.
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While these ramps have been designed to provide public access and public
improvements from Carlsbad Boulevard to the beach, they require that the
vertical seawall be extended significantly seaward to protect them. To
accomodate the ramps and their improvements, roughly 3,900 sq.ft. of sandy
beach would be displaced, with resulting adverse impacts to public access and
recreation opportunities on this heavily-used beach.
While the City of Carlsbad and the State Departments of Parks and Recreation
and Boating and Waterways maintain that the proposed ramps are essential to
the project, an alternative to the present design for the ramps would be to
redesign two of the three proposed ramps - one ramp would be necessary to
provide lifeguard and handicap access - as public access stairways. Only 760
sq.ft. of sandy beach would be displaced if two of the proposed ramps were
redesigned as stairways, giving a net savings of 3,140 sq.ft. of sandy beach
area. However, this redesign would require that the lifeguard towers and the
handicap viewing platforms within the ramps would have to be moved onto the
beach.
In CDP #6-91-60, under the balancing provisions of the Coastal Act, the
Commission and City staff worked to resolve the beach encroachment issue
associated with not only the proposed ramps but also the proposed south
revetment. In exchange for staff's support of the access ramps, the City
agreed to construct a vertical wall similar to that proposed in the middle
portion of the project in place of the proposed south revetment. The redesign
to a vertical wall produces about 3,500 sq.ft. of public beach which almost
offsets the sandy beach displacement of the proposed ramps, about 3,900
sq.ft. Adding beach area displaced by the lifeguard towers and the handicap
viewing platforms would more than offset the differences between the two.
Again, the redesigned project is proposed with the present application.
According to a preliminary design by project coastal engineers, the redesign
of the south revetment to a vertical wall would recapture sandy beach by
siting the vertical wall landward of the proposed revetment and existing fill
slope that supports Carlsbad Boulevard. Although the preferred direction is
always to minimize encroachment and maximize sandy beach area available for
public use, with this redesign and the special conditions attached to this
report, the Commission can find in this particular case that the proposed
shoreline protection has been designed to minimize and offset the potential
impacts of beach encroachment and erosion through an alignment which is
generally set landward of the existing beach profile. Additionally, the
Commission finds that construction of the proposed shoreline protection is
warranted to protect Carlsbad Boulevard, the major coastal access route in the
area, consistent with Policy 4-3 of the certified Mello II LCP.
The north revetment (4001 long, 50' wide, 19' wide crown, top ranging from +17
- +20) would be placed in an area where rip-rap of varying size has been
placed on an on-going basis for a number of years; it would tie into the
existing Agua Hedionda outer lagoon jetty and extend down in front of the
sheet pile wall at its north end. Project plans call for the north revetment
to be built-over existing dumped rock on the slope, using existing
unengineered rip-rap as a base.
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The proposed north revetment would displace up to 5,000 sq.ft. more beach area
than existing rock slope protection. Of this area, up to 3,000 sq.ft. is
above elevation +3 and is composed mostly of cobbles and rock on the rock
slope. The remaining approx. 2,000 sq.ft. below +3 is sand/cobble (depending
on the time of year and beach nourishment operations), which could be used by
strollers and sunbathers at low tide conditions.
Regarding the sand/cobble nature of the beach in the area of the north
revetment, the beach is typically cobble in the winter time, but as a result
of natural littoral cell accretion patterns in the summer and the biannual
beach nourishment program regularly provided by SDG&E, it is generally sandy
during the summer months. Generally, every two years the utility dredges out
the outer basin of Agua Hedionda Lagoon (to benefit cooling operations) and
deposits the beach grade sand within the subject area. As a result of this
replenishment, the subject area becomes sandy beach.
Notwithstanding the fact that the proposed revetment would adversely affect
public access because it would extend further seaward than existing slope
protection, there are a number of reasons why replacing the north revetment
with a vertical seawall is not recommended. First, the north revetment beach
area is not heavily-used by the public as the beach is narrow here, usuable
only at low tides, and access to this area from Carlsbad Boulevard is
difficult—by way of a steep, rock-covered slope. Second, the construction of
a vertical wall in this area would adversely affect public access/circulation
by requiring demolition of existing improvements, disruption of traffic (i.e.,
in order to have a safe excavation slope for the vertical wall, the southbound
traffic lanes along Carlsbad Boulevard would have to be removed), and
extension of the construction period (when compared with the proposed
revetment). Third, while additional beach area would be produced by
construction of the vertical wall, it may increase the hazards to pedestrians
in this area as this beach is adjacent to a large jetty. Consequently, the
Commission finds that redesigning the proposed north revetment is not
required.
The existing rock slope protection is proposed as a foundation for the north
revetment. Initially, the Commission's civil engineer took issue with this
design criterion citing that the existing rock slope protection was unstable
and would not serve as an adequate base for overlaying an engineered
revetment. However, according to the project coastal engineer, the proposed
revetment design includes removal of loose surface rock and debris, filling of
voids with small rock and providing a designed filter to mitigate erosion of
base material and that the designed armor and underlayer rock will protect the
base material from tide and wave action and will limit any future movement.
Consequently, the project coastal engineer concludes that encroachment onto
Carlsbad Boulevard will not be necessary during construction.
The San Diego Association of Governments (SANDAG) has adopted the Shoreline
Preservation Strategy for the San Diego region and is currently working on
techniques toward its implementation. The Strategy considers a full range of
shoreline management tactics, but emphasizes beach replenishment to preserve
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and enhance the environmental quality, recreational capacity, and property
protection benefits of the region's shoreline. As identified in the Strategy,
while shoreline protective devices result in immediate protection for the
endangered property, they also result in long-term adverse impacts on the
beach seaward of the wall or revetment.
The construction of a seawall can have several quantifiable impacts on
shoreline processes and beach access, as well as numerous, less quantifiable
effects which have been discussed elsewhere in current literature on
seawalls. One of the quantifiable impacts from such structures is the seawall
will physically occupy area that would otherwise be available for recreational
use. This is the case with the proposed seawall.
Shoreline protective devices, such as that proposed, fix the inland extent of
the beach. Therefore, when additional erosion occurs seaward of the wall, it
is at the expense of beaches or recreational areas owned or utilized by the
general public. Seawalls inhibit erosion that naturally occurs and sustains
the beach. The two most important aspects of beach behavior are changes in
beach width and changes in the position of the beach. On narrow, natural
beaches, the retreat of the back of the beach, and hence the beach itself, is
the most important element in sustaining the width of the beach over a long
time period. Narrow beaches, typical of most of the California coast, do not
provide enough sacrificial sand during storms to provide protection against
scour caused by breaking waves at the backbeach line. This is the reason the
back boundary of our beaches retreats during some storms. Armoring in the
form of a seawall fixes the backbeach line and interrupts this natural
process. Accordingly, in its review of such projects under Section 30235 and
the access policies of the Coastal Act, the Commission must assess both the
need to protect property and the need to mitigate adverse effects on beach
access and shoreline sand supply.
Funding from a variety of sources will be required to implement the beach
replenishment and maintenance programs identified in the SANDAG Strategy. In
this particular case, the Commission finds that application of an in-lieu fee
to fund beach sand replenishment projects as mitigation for impacts of the
proposed shoreline protective device on beach sand supply and shoreline
processes is not appropriate for the following reasons. The City of Carlsbad,
in cooperation with SDG&E, has maintained an ongoing beach replenishment
effort that has occurred on this beach since the mid 1950s. This beach
replenishment operation routinely places up to 200,000 cubic yards of sand
within the project area annually. In contrast, using the Commission's
methodology for determining the amount of cubic yards of beach area that would
be lost over the long-term as a result of the project, 15,600 cubic yards
would be lost. While placement of sand is not limited to the project area,
the project area has traditionally received the bulk of deposited sands
because it is the most popular public beach in Carlsbad in terms of
attendance.
Placement of dredged sand from the outer basin of Agua Hedionda is placed up
to 1 mile north of the project area based upon the recommendations of the
City's Beach Erosion Committee. This committee, composed of public and
6-94-91
page 12
private members, analyzes on and off-shore profiles and erosion rates to
determine where placement of sand would be most beneficial. Final approval of
sand placement is subject to review and approval by the City's engineering
department, Army Corps, and the Executive Director pursuant to CDP
#6-93-193A. Therefore, The Commission finds this beach replenishment effort
will continue and will adequately offset the long-term impacts associated with
the project.
Additionally, the proposed project is a public seawall, located on public
property and designed to protect a public roadway. Although the effects of
fixing the back line of the beach are the same, regardless of ownership, the
proposed project inherently provides offsetting public benefits which is what
the beach replenishment fee is also designed to do. The project, as proposed,
includes public amenities including stairways, ramps and viewing platforms, an
minimizes encroachment on the beach to the extent practicable . Therefore,
the Commission finds that based on the on-going replenishment program and the
fact that the project is proposing a number of public improvements that would
offset impacts associated with encroachment on public access, the in-lieu fee
for beach replenishment is not applcable, in this particular case.
Special Condition #1 requires the applicant to submit certification by a
registered civil engineer that the approved shoreline protective device has
been constructed in accordance with the approved plans and is designed to
withstand storms comparable to the winter storms of 1982-83. It also requires
post-certification of the work to verify that the work has been completed in
accordance with the approved plans and specifications. For the proposed
devices to be effective in providing shoreline protection, and safe for the
public, they must be properly maintained.
Special Condition #2 places such responsibility for maintenance with the
applicant (City of Carlsbad) unless such responsibility is assumed by the
State Department of Parks and Recreation or other public agency acceptable to
the Executive Director. The special condition also serves to advise the
applicant that subsequent repair or maintenance activity involving shoreline
protection may require review under the coastal development permit review
process.
Special Condition #3 is an advisory condition. The condition requires that
during construction, disturbance to sand and intertidal areas be minimized and
that any beach sand excavated be redeposited on the beach. The condition also
specifies that local sand or cobbles may not be used as backfill or
construction material for the project.
Special Condition #4 requires the submittal of an executed construction
easement from the State Department of Parks and Recreation which indicates
their approval of the applicant's work, the proposed construction schedule and
construction access and staging plans as they affect State Parks property. If
the Commission's approval in not in concert with the conditions of this
easement, an amendment to this permit may be necessary.
In addition, the Commission's standard hold harmless agreement (Special
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page 13
Condition No. 5) has been attached to notify the applicant of the risks
involved with construction of the project along the shoreline and requires the
applicant to waive any liability for the Commission in approving the project.
As conditioned, the Commission finds the project consistent with Sections
30235 and 30253 of the Coastal Act.
3. Public Access/Scenic Resources. Section 30604(c) requires that for
any development between the nearest public road and the sea, the Commission
must find that the permitted development is in conformity with the public
access and public recreation policies of Chapter 3 of the Coastal Act. The
proposed project lies between the sea and the first designated roadway
(Carlsbad Boulevard) and, as proposed, actually involves encroachment onto the
beach itself. Section 30210 of the Coastal Act states:
In carrying out the requirement of Section 4 of Article X of the
California Constitution, maximum access, which shall be
conspicuously posted, and recreational opportunities shall be
provided for all the people consistent with public safety needs and
the need to protect public rights, rights of private property owners,
and natural resource areas from overuse.
As noted, in its earlier permit action the Commission required the project to
be redesigned to minimize beach encroachment so that adverse impacts to public
access from the seawall would be mitigated. With the redesign the Commission
finds the project consistent with Sections 30210 and 30211 of the Act.
Vertical access will be provided by three new ramps and two new stairways from
Carlsbad Boulevard to the beach. Thus, a total of five public accessways will
be newly provided for this 3,185-1inear-foot stretch of beach; these stairways
will be provided at an interval of roughly every 720 feet.
Special Condition #6 requires the submittal of a construction schedule and
construction access and staging plans so that construction activities which
would adversely affect public access to the beach are prohibited between
Memorial Day and Labor Day of any year. The condition also requires that all
construction staging, storage of materials, and other construction related
activities in support of the project shall occur only within the two (2) areas
immediately north and south of the SDG&E warm water outlet jetty and be
appropriately fenced and protected for public safety. Finally, the condition
requires that two-way traffic, north and south, will be available on Carlsbad
Boulevard at all times during construction to ensure that public
access/circulation is maintained in this heavily used visitor destination area.
Special Condition #1 requires the submittal of documentation from the State
Lands Commission that either no State lands are involved with the project or
that the development on the State lands that are involved has either been
authorized or may proceed without prejudice to a final agreement to use such
lands. The Commission finds that, with the proposed south revetment deleted
from project plans and the remaining aspects of the project addressed in the
special conditions of the permit, the project can be found to be consistent
with all the public access and recreation policies of the Coastal Act.
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page 14
Scenic Resources/Height of Nail
The project proposes a 3.5-feet high above sidewalk (4-feet high above beach)
portion of the seawall that runs the length of the project along the seaward
edge of the sidewalk. Current unobstructed views to the beach and nearshore
for traveling motorists would be replaced with a continuous seawall. This
stretch of road is one of the few in North County where such views of the
shoreline and horizon are available. Also, it is one of a few areas where a
lagoon is adjacent to the eastern side of Coast Highway so the sense of
openness is significant and not currently obstructed by structures or
development. For those reasons staff recommended in CDP #6-91-60 that seawall
height be reduced to 2 feet above the sidewalk.
The City found that the proposed 3.5-foot section of the wall above the
sidewalk was essential to achieving the goals of the project and was concerned
about the potential liability resulting from losses, damage, injuries, etc.,
that may result from constructing the project with a lesser wall height that
did not meet the design criteria to deal with anticipated storm wave heights
or did not meet Uniform Building Code design standards for pedestrian
accessways and stairways (42 inches minimum).
The Commission supported the City's position and found that a redesign to a
two-foot-high wall was unfeasible and unnecessary to find the project
consistent with the resource protection policies of the Mello II LCP. The
Commission noted that the 1.5-foot difference between the proposed wall height
and the preferred wall height was not enough to significantly improve public
views. The Commission noted that the redesign would result in more frequent
overtopping of the wall and thus would unacceptably subject Carlsbad Boulevard
and its improvements to flooding and damage and would increase hazards to the
public. As before and with this application the Commission finds that a
redesign would not signficantly enhance public views to and along the
shoreline to warrant justification of more frequent overtopping of the
proposed seawall, and the proposed wall height itself would not result in
significant obstruction of ocean views. Therefore, the Commission finds that
the proposed wall can be found consistent with the Mello II LCP.
4. Local Coastal Planning. The certified Carlsbad LCP Mello II segment
contains detailed policies regarding new development along the shoreline.
Specifically, the Coastal Development Overlay (C-D) zone was included in the
certified LCP pursuant to the policies of Chapter 3 of the Coastal Act
regarding public access, shoreline processes and geological stability. The
policies and ordinances of the C-D zone state in part:
Revetments, breakwaters, groins, harbor channels, seawalls, cliff
retaining walls, and other such construction that alters natural
shoreline processes shall be permitted when required to serve
coastal-dependent uses or to protect existing structures or public
beaches in danger from erosion, and when designed to eliminate or
mitigate adverse impacts on local shoreline sand supply. As a
condition of approval, permitted shoreline structures may be required
to replenish the beach with imported sand. Provisions for the
maintenance of any permitted seawalls shall be included as a
6-94-91
page 15
condition of project approval. As a further condition of approval,
permitted shoreline structures shall be required to provide public
access...
No excavation, grading or deposit of natural deposit materials shall
be permitted on the beach or the face of the bluff except to the
extent necessary to accomplish construction pursuant to this section.
(Ordinances 4-b and 5-(a-2) of the C-D overlay zone)
The proposed project involves construction of a shoreline protection device.
The Commission has found that construction of the proposed seawall is
warranted and, as conditioned, will be designed to minimize disturbances of
the beach and provide public access to and along the shoreline. The
additional special conditions have been attached to reflect the policies and
ordinances of the C-D zone of the Carlsbad LCP. As conditioned, project
approval should not prejudice the ability of the City of Carlsbad to prepare a
fully certifiable local coastal program.
5. California Environmental Quality Act Section 13096 of the
Commission's administrative regulations requires Commission approval of the
coastal development permit to be supported by a finding showing the permit, as
conditioned, to be consistent with any applicable requirements of the
California Environmental Quality Act (CEQA). Section 21080.5(d)(2)(i) of CEQA
prohibits a proposed development from being approved if there are feasible
alternatives or feasible mitigation measures available which would
substantially lessen any significant adverse impact which the activity may
have on the environment.
The proposed project has been conditioned in order to be found consistent with
the public access and recreation, visual resources, and hazard policies of the
Coastal Act. Mitigation measures, including conditions addressing storm
design, construction access and staging areas, construction materials, and an
assumption of risk will minimize all adverse environmental impacts. As
conditioned, there are no feasible alternatives or feasible mitigation
measures available which would substantially lessen any significant adverse
impact which the activity may have on the environment. Therefore, the
Commission finds that the proposed project, as conditioned to mitigate the
identified impacts, is the least environmentally damaging feasible alternative
and can be found consistent with the requirements of the Coastal Act to
conform to CEQA.
STANDARD CONDITIONS:
1. Notice of Receipt and Acknowledgement. The permit is not valid and
development shall not commence until a copy of the permit, signed by the
permittee or authorized agent, acknowledging receipt of the permit and
acceptance of the terms and conditions, is returned to the Commission
office.
6-94-91
page 16
2. Expiration. If development has not commenced, the permit will expire two
years from the date on which the Commission voted on the application.
Development shall be pursued in a diligent manner and completed in a
reasonable period of time. Application for extension of the permit must
be made prior to the expiration date.
3. Compliance. All development must occur in strict compliance with the
proposal as set forth below. Any deviation from the approved plans must
be reviewed and approved by the staff and may require Commission approval.
4. Interpretation. Any questions of intent or interpretation of any
condition will be resolved by the Executive Director or the Commission.
5. Inspections. The Commission staff shall be allowed to inspect the site
and the development during construction, subject to 24-hour advance notice.
6. Assignment. The permit may be assigned to any qualified person, provided
assignee files with the Commission an affidavit accepting all terms and
conditions of the permit.
7. Terms and Conditions Run with the Land. These terms and conditions shall
be perpetual, and it is the intention of the Commission and the permittee
to bind all future owners and possessors of the subject property to the
terms and conditions.
(9860A)
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