HomeMy WebLinkAboutSUP 06-10X2A; AGUA HEDIONDA OUTER LAGOON MAINTENANCE; OUTER AGUA HEDIONDA LAGOON 2017-2018 DREDGE CYCLE, SAND MANAGEMENT PLAN; 2017-12-01CABRILLO POWER I LLC ENCINA POWER STATION
Outer Agua Hedionda Lagoon, November 2013 (Source: SANDAG 2014 Shoreline Monitoring Program)
OUTER AGUA HEDIONDA LAGOON
2018 DREDGE CYCLE
______________________
SAND MANAGEMENT PLAN
Prepared by:
Cabrillo Power I LLC
Encina Power Station
4600 Carlsbad Blvd.
Carlsbad, CA 92008
Prepared for:
City of Carlsbad, California
in fulfillment of
Special Use Permit 06-10X2(A)
OUTER AGUA HEDIONDA LAGOON
2018 DREDGE CYCLE
______________________
SAND MANAGEMENT PLAN
Prepared by:
Cabrillo Power I LLC
Encina Power Station
4600 Carlsbad Blvd.
Carlsbad, CA 92008
Prepared for:
City of Carlsbad, California
in fulfillment of
Special Use Permit 06-10X2(A)
Revised
December 2017
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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EXECUTIVE SUMMARY
This sediment management plan has been prepared in fulfillment of Conditions 7 and
8 of the City of Carlsbad Special Use Permit (SUP) 06-10X2(A).
Cabrillo Power I LLC plans to conduct maintenance dredging in 2018 to remove a
flood-tide shoal in the outer Agua Hedionda Lagoon in to order maintain cooling water
flowrates. Similar operations have been performed over the last six decades. Up to
500,000 cubic yards (cy) of sand may be removed from the lagoon. In keeping with past
operations, the dredged sand will be placed on adjacent beaches: North Beach, Middle Beach,
and South Beach. Operations will be conducted between January and April 2018.
Sand placement quantities for each receiver beach were determined by Dr. Scott
Jenkins based on an assessment of the optimal sand carrying capacity for each reach and the
current beach condition defined by a December 2017 beach profile survey. Based on this
analysis, no sand will be placed at North Beach. All of the dredged material will be placed on
Middle and South Beach, with an approximate distribution of 67% and 33%, respectively.
The proposed sand placement quantities and approximate schedule are summarized below.
Beach Placement Quantities and Schedule
Receiver Site Placement Quantity Approximate Schedule
Middle Beach up to 335,000 cy January 5 to February 20
South Beach up to 165,000 cy February 20 to March 20 1
North Beach 0 cy n/a
Total up to 500,000 cy
Note:
1 Sand placement operations my extend beyond March 20 if adverse weather conditions or equipment
issues are encountered. No sand will be placed on beaches after April 15.
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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TABLE OF CONTENTS
Title Page No.
EXECUTIVE SUMMARY .................................................................................................. i
TABLE OF CONTENTS ................................................................................................... iii
LIST OF TABLES .............................................................................................................. v
LIST OF FIGURES ............................................................................................................. v
1. INTRODUCTION ................................................................................................... 1
2. PROJECT DESCRIPTION ..................................................................................... 2
2.1 Dredging Operations ................................................................................ 2
2.2 Beach Placement Operations ................................................................... 2
2.3 Summary of Project Equipment ................................................................ 6
2.4 Access and Pedestrian Control ................................................................ 6
2.5 Contact Information ................................................................................. 7
3. PROJECT SCHEDULE .......................................................................................... 8
4. SAND PLACEMENT QUANTITY DETERMINATION ..................................... 9
4.1 Beach Profile Survey ................................................................................ 9
4.2 Sand Quantity Calculation Methods and Results ................................... 11
5. SUMMARY .......................................................................................................... 15
6. REFERENCES ...................................................................................................... 16
APPENDIX A. BEACH PROFILE PLOTS
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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LIST OF TABLES
Title Page No.
Table 1. Target Placement Quantities ........................................................................ 5
Table 2. Schedule for 2018 Dredge Cycle ................................................................. 8
Table 3. Optimal Sand Placement Quantity for Each Receiver Beach ................... 13
Table 4. Summary of Beach Placement Quantities and Schedule ........................... 15
LIST OF FIGURES
Title Page No.
Figure 1. Project Location Map .................................................................................. 3
Figure 2. Dredge Pipeline Map ................................................................................... 4
Figure 3. Public Signage ............................................................................................. 6
Figure 4. Beach Profile Transect Location Map ....................................................... 10
Figure 5. North Beach Profiles for the Reach from Cab-07 to Cab-09 .................... 13
Figure 6. North Beach Profiles for the Reach from Cab-09 to Cab-12 .................... 14
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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Outer Agua Hedionda Lagoon
2018 Dredge Cycle ______________________
Sand Management Plan
1. INTRODUCTION
The rubble mound jetties at the Agua Hedionda Lagoon entrance were constructed in
1954 to maintain a stable inlet for the Encina Power Station (EPS) seawater intake (Shaw,
1980). Initial dredging to create the cooling water basin was conducted at the same time.
Ongoing maintenance dredging performed during the last six decades has allowed the lagoon
entrance to remain open to tidal exchange.
Since 1994, maintenance dredging has been conducted at intervals of one to four years
to remove a flood-tide shoal that forms in the outer Agua Hedionda Lagoon and to maintain
cooling water flowrates. Between 1994 and 2015, approximately 3.3 million cubic yards (cy)
of sediment were dredged from the outer lagoon and placed on neighboring beaches (Coastal
Frontiers, 2017a). Individual dredge cycle quantities have ranged from 159,000 to
429,000 cy. The most recent operation, completed in 2015, accounted for 295,000 cy.
Cabrillo Power I LLC (Cabrillo) plans to conduct the next phase of maintenance
dredging in 2018. As during past episodes, sediment removed from the lagoon will be placed
on adjacent beaches: The work will be performed in accordance with the stipulations in the
following permits:
City of Carlsbad Special Use Permit (SUP) 06-10X2(A)
US Army Corps of Engineers Permit SPL-2001-00328-RRS
California Coastal Commission Coastal Development Permit No. 6-17-0732
San Diego Regional Water Quality Control Board General National Pollution
Discharge Elimination System General Permit for Maintenance Dredge/Fill
Projects Conducted in Navigable Waters within the San Diego Region 96-32
California Department of Parks and Recreation Right of Entry Permit
California State Lands Commission Lease 932.1
This sediment management plan has been prepared in fulfillment of Conditions 7 and
8 of the City of Carlsbad SUP. The following sections provide a project description,
summarize the project schedule, describe the sand placement quantity calculations, and
summarize the findings.
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2. PROJECT DESCRIPTION
Dredging will be limited to the outer lagoon basin, which is bordered on the east by
the railroad bridge and on the west by Carlsbad Boulevard (Figure 1). In accordance with the
SUP, up to 500,000 cy may be removed from the lagoon. In keeping with past operations, the
dredged sand will be placed on adjacent beaches: North Beach, Middle Beach, and South
Beach (Figure 1). The amount of sand placed on each of the receiver beaches will be
optimized based on current conditions and the carrying capacity for each beach as determined
by Jenkins (2017a, 2017b).
2.1 Dredging Operations
Dredging of the outer Agua Hedionda Lagoon will be performed using a diesel
powered dredging hull barge. During operations, the dredge hull would be stabilized by wire
cables that are secured to existing anchors on the shore of the lagoon.
2.2 Beach Placement Operations
The dredged material (slurry) will be pumped to each of the receiver beaches (North,
Middle and South Beach; Figure 1) through a 20-inch diameter pipeline. A floating section of
pipe will convey the slurry from the dredge to the lagoon shoreline, where it will connect with
a land-based pipeline that will deliver the material to the receiver beach. Figure 2 shows the
approximate dredge pipeline routes for each receiver site. When material is placed at North
Beach, the pipeline traverses under the Carlsbad Boulevard Bridge and then north along the
back of the beach as far as Pine Avenue. For the Middle and South Beach receiver sites, an
existing underground pipe under Carlsbad Boulevard will be utilized. In the case of South
Beach, the pipelines will be extended along the back of the beach at Carlsbad State Beach to
reach the south side of the EPS discharge jetty. Depending on shoal conditions, the pipe to
Middle Beach may traverse under the Carlsbad Boulevard Bridge and then south for a portion
of the discharge time on Middle Beach.
As described above, the slurry arriving from the dredge discharge pipeline is a mix of
sand and water. Temporary dikes and berms will be constructed at the discharge points to de-
water the slurry and aid in the retention of sand at the receiver beaches. As currently
envisioned, two dikes would be constructed – one that is perpendicular to the beach connected
to one that is parallel to the beach (forming an “L”). The dredged slurry will be discharged
behind the dikes. Where sand is not present on the existing beach an initial quantity of sand
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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Figure 1. Project Location Map
Note: North Beach receiver site used only during dredge cycles when sand placement is dictated by
existing beach condition.
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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Figure 2. Dredge Discharge Pipeline Routes
Note: North Beach discharge pipeline installed only during dredge cycles when sand placement is dictated
by existing beach condition.
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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will be discharged on the highest portion of the beach and used to construct a dike. These
methods have been used effectively in the past to promote sediment settling onto the beach
instead of remaining in suspension and being transported back into the surf zone.
The dikes and berms also are used to insure shoreline ocean turbidity does not exceed
the limit of the San Diego Regional Water Quality Control Board General National Pollution
Discharge Elimination System General Permit for Maintenance Dredge/Fill Projects
Conducted in Navigable Waters within the San Diego Region 96-32. This turbidity is
continually monitored during discharge by operating personnel.
The discharge point is directed according to the pre-determined sediment placement
plan. Once the material is de-watered, front-end loaders spread the sand on the beach and into
the required beach profile configuration. As required by Condition 9 of the SUP, the beach
berm will be no taller than 6 ft on the eastern aspect and will be groomed and flattened to
provide towel space. The material will be placed in such a manner that the beach profile
slopes gradually to the surf zone. If a steep scarp forms on the foreshore following a storm or
during the equilibration process, this region will be regraded to a gentler slope. Material will
not be placed in areas that will block existing drainage. In addition, a minimum 5-ft wide
path of travel will be maintained between sand placement operations and sea walls (both
public and private).
Target sand placement quantities for North, Middle, and South Beach were developed
based on an assessment of sediment carrying capacity and the current condition of the beaches
conducted by Dr. Scott Jenkins (Table 1). As described in Section 4, no sand will be placed at
North Beach during the 2018 dredge cycle because the existing beach volume exceeds
optimal condition. As a result, all of the dredged material (up to 500,000 cy) will be placed at
Middle and South Beach with an approximate distribution of 67% and 33%.
Table 1. Target Placement Quantities
Receiver Site Placement Quantity
North Beach
North Jetty to Maple Ave. 0 cy
Maple Ave. to Pine Ave. 0 cy
Middle Beach up to 335,000 cy
South Beach up to 165,000 cy
TOTAL up to 500,000 cy
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2.3 Summary of Project Equipment
The designated staging area for equipment and materials is on the North and West
shoreline of the outer lagoon. The following equipment will be utilized.
Hydraulic dredge.
Slurry discharge pipe
o Poly and Steel pipe within the lagoon (floating)
o Poly pipe along the shoreline
Rubber tired loaders – one full time, second as needed
Pickup truck (4x4), for support on the shoreline and public roadways
2.4 Access and Pedestrian Control
Cabrillo regards safety of the public and personnel foremost over all other tasks.
Portable signage will be used at each discharge location to advise pedestrians of current
work. An example of this signage is provided in Figure 3. This signage is relocated as the
dredge slurry discharge point moves.
Figure 3. Public Signage
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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No forms of public access to the shoreline will be blocked during sand deposition
operations. Designated access ways, over or around obstructions, will be provided. Access
for public safety vehicles also will be maintained. When discharging to South Beach, the
piping is placed through an opening in the EPS discharge channel fencing to ensure
pedestrian safety. At no time will piping be placed on the pedestrian sidewalks along
Carlsbad Boulevard. A monitor will be stationed at the north and south ends of the active
work area to prevent foot traffic in the immediate construction zone. Appropriate signage
and construction fencing will be used to identify the construction zone. The beach access
areas will be left in a safe condition at the end of each work day.
A flag crew will be utilized while moving or operating equipment on the beach. The
pickup truck used to support the operation will utilize the shoreline and public roadways to
avoid interference with pedestrian flow. As stipulated by Condition 9 of the SUP, a
minimum 5-ft wide path of travel will be maintained between sand placement operations
and sea walls (both public and private).
Discharge point relocation operations will be conducted during low pedestrian traffic
times to the extent possible. In addition, Cabrillo intends to intermittently stage project
personnel to properly answer any questions the public may have on the process.
2.5 Contact Information
The project is being conducted under the supervision of Ms. Sheila Henika. Her
contact information is provided below.
Sheila Henika
Encina Power Station
4600 Carlsbad Boulevard
Carlsbad, CA 92008
(760) 268-4018 voice
(760) 535-2705 cell (24 hour response)
(760) 268-4026 fax
sheila.henika@nrg.com
Should emergency response be necessary for the dredge activity, you may contact Ms.
Henika, or follow the Hazardous Materials Business Plan Emergency Notification as provided
to the Carlsbad Fire Department. Namely, contact the Main Encina Power Station Control
Room at (760) 268-4062 or the Shift Supervisor at (760) 268-4079.
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3. PROJECT SCHEDULE
The dredging and sand placement schedule shall be similar to past activities and
conform with the requirements stipulated in the California Coastal Commission Coastal
Development Permit. As indicated previously, and discussed in Section 4, no sand will be
placed at North Beach during the 2018 dredge cycle. The anticipated schedule is shown in
Table 2.
Table 2. Schedule for 2018 Dredge Cycle
Activity Dates
Dredging January 5 to April 15
Sand Placement
Middle Beach January 5 to February 20
South Beach February 20 to March 20 1
North Beach n/a
Total Period of Activity January 5 to April 15
Note:
1 Sand placement operations my extend beyond March 20 if adverse weather conditions or equipment
issues are encountered. No sand will be placed on beaches after April 15.
It is anticipated that all work will be conducted during daylight hours and between
Monday and Friday. If the schedule is delayed by storm activity, work may be conducted
during daylight hours on Saturdays with appropriate authorization. No activities are
anticipated during evening hours or on Sundays.
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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4. SAND PLACEMENT QUANTITY DETERMINATION
The optimal sand placement quantities shown in Table 1 were determined by Dr. Scott
Jenkins based on an assessment of the carrying capacity of each receiver site (Jenkins, 2017a,
2017b).
4.1 Beach Profile Survey
A beach profile survey was conducted on December 5, 2017 to document the current
condition of the beaches. Data were obtained on 13 beach profile transects (Figure 4). Ten of
the transects had been surveyed in 2014 and 2015 on behalf of Cabrillo, while three were
surveyed for the first time in 2017. Four of the Transects correspond to historical locations
included in the SANDAG Shoreline Monitoring Program and the City of Carlsbad Beach
Monitoring Program (Coastal Frontiers, 2017a; 2017b). The data acquisition and reduction
methods were comparable to those employed on the beach profile surveys conducted under
the aforementioned programs.
Survey control information was provided by Cabrillo prior to the field activities. The
coordinates of the control points were confirmed at the time of the survey using real-time
kinematic (RTK) GPS techniques.
Survey activities were conducted under ideal conditions, with offshore winds and
waves typically less than 3 ft. Data were acquired along each transect from the landward limit
of the sandy beach to wading depth, which typically corresponded to 8 to 15 ft below Mean
Lower Low Water (MLLW) Datum depending on the prevailing water level. The beach and
surf zone were surveyed using a total station and a survey rodman. The total station was used
to determine the position and elevation of the beach at each location occupied by the rodman.
Each transect was surveyed from the back beach seaward through the surf zone until the
survey rod no longer protruded above the water surface when held erect.
The data from the wading survey were processed using software developed by
Trimble. The raw total station data were read by the software, and the coordinates and
elevation of each data point were calculated and inserted into a CAD drawing.
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Figure 4. Beach Profile Transect Locations
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The electronic total station used to conduct the survey is capable of measuring
elevation differences to within 0.1 ft and ranges to within 0.5 ft. However, because the
swimmer was subjected to waves and currents in the surf zone, the horizontal position
perpendicular to each transect (parallel to the shoreline) varied from minimal at short ranges
to approximately 15 ft at the offshore end.
The beach profile plots developed from the December 2017 survey data are provided
in Appendix A. Selected historical data are displayed for each transect where such data are
available. The range on each profile plot represents the distance in feet seaward of the
transect origin measured along the transect alignment. The elevation is given in feet relative
to MLLW (1983-2001 Epoch).
4.2 Sand Quantity Calculation Methods and Results
Jenkins determined the optimal sand carrying capacity of each receiver beach based on
the comparison of the wave cut platform and the elliptic cycloid equilibrium profile. In
absence of a definitive data defining the wave cut platform in the project area, initial work
conducted by Jenkins (2017a, 2017b) utilized the beach condition defined by a December 22,
2014 beach profile survey as a proxy because it represented the most eroded condition among
the limited data set made available for the assessment. The wave cut platform configuration
for the North Beach region subsequently was re-evaluated based on an assessment of
additional beach profile data obtained by SANDAG and the City of Carlsbad for the 16-year
from 1997 to 2012 (SANDAG, 2017).
The carrying capacity (or optimal sand volume for each beach) is determined by the
critical mass (Jenkins and Inman, 2006 and Jenkins, et al., 2007) based on the elliptic cycloid
profile. The critical mass is calculated from maximum wave heights and sand grain sizes
according to:
9.0
1.241023.1
HhVcc
with:
2
o
c
ecsinh D
D
kh
HKh
and:
5/125/15/22
gH
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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Here ch is the closure depth; is a non-dimensional empirical parameter, D2 is the shorerise
median grain size; and Do is a reference grain size ; /2T is radian frequency; k is the
wave number; is the shoaling factor relating breaker height to incident wave height
bHH/; g is acceleration of gravity; and is a factor relating the depth of wave
breaking bh to breaker height, bbhH. For the critical mass calculations determining
optimal placement volume, the following values for free parameters were used:
mDK100~and,33.0~,0.2~oe . The optimal carrying capacities (critical mass) for each
reach are summarized in Table 3.
The optimal sand placement quantities for each receiver beach were determined by
comparing the existing beach condition with the critical sand volume determined by Jenkins.
The existing beach condition is defined by the December 5, 2017 beach profile survey. The
results are summarized in Table 3. The volume calculations were performed with surface
modeling software.
As indicated in Table 3 and in Figures 5 and 6, the residual sand volume atop the re-
evaluated wave cut platform at the time of the 5 December 2017 survey exceeds the critical
mass calculated in Jenkins (2017b) by a factor of more than in the North Beach-Maple Ave to
Pine Ave stretch and by a factor of nearly three in the North Beach-North Jetty to Maple Ave
stretch. In accordance with the Condition 8 of the SUP, no additional sand will be placed at
North Beach because the existing volume exceeds the optimal volume. As a result, the
dredged material (up to 500,000 cy) will be placed at Middle and South Beach with an
approximate distribution of 67% and 33%, respectively (Jenkins, 2017c). The target
placement quantities for each beach are shown in Table 3.
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Table 3. Optimal and Target Sand Placement Quantity for Each Receiver Beach
Receiver Site Optimal
Sand Volume 1
December
2017 Residual
Sand Volume 2
Optimal
Placement
Volume 3
Target
Placement
Volume 4
North Beach
North Jetty to Maple Ave. 79,500 cy 223,700 cy 0 cy 0 cy
Maple Ave. to Pine Ave. 55,600 cy 141,000 cy 0 cy 0 cy
Middle Beach 134,600 cy 31,000 cy 103,600 cy up to 335,000 cy
South Beach 66,300 cy 18,400 cy 47,900 cy up to 165,000 cy
TOTAL up to 500,000 cy
Notes:
1 Determined by critical mass per Jenkins and Inman, (2006) and Jenkins (2017a, 2017b, 2017c).
2 Based difference between critical mass and December 5, 2017 beach profile survey (Section 4.1).
3 Calculated as difference between Optimal Sand Volume and December 2017 Residual Sand Volume.
4 Target sand placement quantity for North Beach cannot exceed the optimal placement volume. The balance
of dredged material (up to 500,000 cy) will be placed at Middle and South Beach with an approximate
distribution of 67% and 33%, respectively.
Figure 5. North Beach Profiles for the Reach From Cab-07 to Cab-09
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Figure 6. North Beach Profiles for the Reach From Cab-09 to Cab-12
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
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5. SUMMARY
Cabrillo plans to conduct maintenance dredging in 2018 to remove a flood-tide shoal
in the outer Agua Hedionda Lagoon in order maintain cooling water flowrates. Similar
operations have been performed over the last six decades. Up to 500,000 cy of sand may be
removed from the lagoon. In keeping with past operations, the dredged sand will be placed
on adjacent beaches: North Beach, Middle Beach, and South Beach. Operations will be
conducted between January and April 2018.
Sand placement quantities for each receiver beach were determined by Dr. Scott
Jenkins based on an assessment of the optimal sand carrying capacity for each reach and the
current beach condition defined by an December 2017 beach profile survey. The proposed
sand placement quantities and approximate schedule are summarized in Table 4.
Table 4. Beach Placement Quantities and Schedule
Receiver Site Placement Quantity Approximate Schedule
Middle Beach up to 335,000 cy January 5 to February 20
South Beach up to 165,000 cy February 20 to March 20 1
North Beach 0 cy n/a
Total up to 500,000 cy
Note:
1 Sand placement operations my extend beyond March 20 if adverse weather conditions or equipment
issues are encountered. No sand will be placed on beaches after April 15.
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6. REFERENCES
Coastal Frontiers Corporation, 2017a, “SANDAG 2016 Regional Beach Monitoring
Program – Annual Report”, Moorpark, CA, 138 pp. + app.
Coastal Frontiers Corporation, 2017b, “City of Carlsbad Beach Spring 2017 Beach Profile
Survey”, letter report to Ms. Aeryn Donnelly-Terrey dated July 28, 2017, from Coastal
Frontiers Corporation, Moorpark, CA.
Jenkins, S. A. and D. L. Inman, 2006, “Thermodynamic solutions for equilibrium
beach profiles”, Jour. Geophys. Res., v.3, C02003, doi:10.1029/2005JC002899, 2006.
21pp.
Jenkins, S. A., Inman, D.L., Michael D. Richardson, M.D., Thomas F. Wever, T.F. and J.
Wasyl, 2007, “Scour and burial mechanics of objects in the nearshore”, IEEE
Jour.Oc.Eng, vol.32, no. 1, pp 78-90
Jenkins, S. A., 2017a, “Beach Equilibrium Analysis of North Beach Disposal Options for
Dredged Sands from Agua Hedionda Lagoon, Carlsbad, CA,” submitted to Cabrillo
Power I LLC, 66 pp.
Jenkins, S. A., 2017b, “Beach Equilibrium Analysis of Middle and South Beach Disposal
Options for Dredged Sands from Agua Hedionda Lagoon, Carlsbad, CA,” submitted
to Cabrillo Power I LLC, 72 pp.
Jenkins, S. A., 2017c, “Cabrillo Power I LLC, Encina Power Station, Outer Agua Lagoon
Maintenance Dredging Coastal Development Permit.”, letter to Ms. Erin Prahler,
California Coastal Commission, San Diego Coast District Office, dated 6 September
2017, Poway, CA.
SANDAG, 2017, “Shoreline Management” from http://www.sandag.org/index.asp?
subclassid=32&fuseaction=home.subclasshome
Shaw, Martha J., 1980, “Artificial Sediment Transport and Structures in Coastal Southern
California”, University of California, San Diego, Scripps Institute of Oceanography,
SIO Reference No. 80-41, La Jolla, CA, 109pp.
Outer Agua Hedionda Lagoon 2018 Dredge Cycle Sand Management Plan
APPENDIX A
BEACH PROFILE PLOTS
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−01Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−02Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−03Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−04Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−05Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−06Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−07Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−07.5Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−08Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−09Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−10Sep 2013Nov 2014Dec 2014Apr 2015Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−11Oct 2017Dec 2017
−50050100150200250300350400450500550600650700−10−505101520MSLCross−Shore Distance (Feet Seaward of Transect Origin)Elevation (Feet, MLLW)Transect Cab I−12Oct 2017Dec 2017