HomeMy WebLinkAbout; ; Semi-AnnBeach Profile Surveys & Analysis Oct 91; 1992-03-01m
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m SEMI-ANNUAL BEACH PROFILE
SURVEYS AND ANALYSIS
FOR OCTOBER 1991
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SUBMITTED TO
CITY OF CARLSBAD
CALIFORNIA
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SUBMITTED BY
TEKMARINE, INC.
ARCADIA, CALIFORNIA
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MARCH 1992
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EXECUTIVE SUMMARY
This report describes the results of the Carlsbad Beach
Profile Survey conducted in October 1991.
1. Beach changes during the recent one-year period reflected the
dominant influence of the two factors which normally exert
major influence on the state of the beach in the study region:
wave climate and supply of sand.
2. A very moderate wave climate prevailed during the most recent
study period between October 1990 and October 1991,
essentially making it the fourth consecutive year of moderate
wave action. Reflecting this situation, volumetric changes
in the beach profiles during the recent one-year period
remained very modest.
3. During the recent study period (October 1990 through October
1991) the Carlsbad shoreline received major replenishment of
sand when San Diego Gas & Electric Company placed a total of
465,000 cubic yards of sand on the shoreline both north and
south of Agua Hedionda during December 1990 through April
1991. In contrast, supply of sand to the Oceanside shoreline
during the recent one-year period (October 1990 through
October 1991) totaled a meager 5,000 cubic yards from the
Oceanside sand bypassing system which had been under repair
for most of this period.
4. Reflecting the impact of the recent SDG&E beach nourishment
program, the profiles along the Carlsbad shoreline experienced
general accretion; progressively larger amounts of accretion
occurred in the profiles closer to the center of the beach
nourishment; and volumetric gains in the accreted profiles in
Carlsbad were concentrated mainly above MLLW. In fact, the
beach sediment volume above MLLW as of October 1991 was
greater than at any time since the semi-annual beach survey
program was commenced in September 1987.
5. On the other hand, the beaches at South Oceanside were eroded
during the October 1990 - October 1991 comparison period.
6. The contrast in beach volume between Carlsbad and Oceanside
profiles Were also manifest in beach width. Compared with
October 1990, the shorelines of October 1991 advanced about
44 ft seaward within Carlsbad, but retreated about 35 ft
within South Oceanside.
7. Of all the profiles surveyed in our program, only the
Oceanside Boulevard (OS-960) shoreline showed a distinct trend
for erosion over the past several years. The shoreline at
Tamarack Avenue and Acacia Avenue appeared to be quasi-stable
during this period. All other shorelines in Carlsbad
exhibited a trend for advance.
BEACH SURVEYS AND ANALYSIS
CARLSBAD, CALIFORNIA
OCTOBER 1991
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TABLE OF CONTENTS
4*
«• Title Page No,
* EXECUTIVE SUMMARY i
TABLE OF CONTENTS ii
* LIST OF FIGURES iii
* LIST OF TABLES iv
•" 1. Introduction 1
M 2. Background Information 1
fam
3. Recent Beach Nourishment Operations 4
4. Field Operations 6m
m 4.1 Survey Procedures 6
4.2 Survey Stations 6
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— 5. Survey Results 11
5.1 The Data 11
5.2 Profile Changes 12M 5.3 Sediment Volume 12
5.4 Shoreline Changes 17<••
ta 6. Conclusions 21
P. REFERENCES "... 23
*" APPENDIX
A: Wading Profiles, Sept 1987 - Oct 1991
** B: Wading Profiles, Sept 1987 - Oct 1991
«• C: Time Histories of MLLW Shoreline, Oct 1983 - Oct 1991
11
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0 LIST OF FIGURES
m Figure No. Page No,
1 Beach Replenishment, December 1990-April 1991 . 5
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m 2 Survey Methods ................. 7
il 3 Location of Range Lines ............ 8
m 4 Profile Accretion Near Agua Hedionda,
m October 1990 - October 1991 ......... 13
• 5 Profile Erosion at Oceanside,
October 1990 - October 1991 ......... 14
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History of MLLW Shoreline Position 19
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m LIST OF TABLES
^ Table No. Page No,
1 List of Range Lines, Azimuths, Monument
^ Elevations, and Survey Dates ........ 9
•2 Volume In Profile Above MLLW (CY/LF) .... 15
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m 3 Volume in Profile Above -30 ft, MLLW (CF/LF) 16
m 4 History of Average Sediment volume in the
Profiles Above MLLW ............ 18
5 History of Average Sediment Volume in the
1! Long Profiles Above -30 Ft, MLLW ...... 18
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6 History of Average Sediment Volume Between
m 0 and -30 Ft, MLLW ............. 18
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IV
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BEACH SURVEYS AND ANALYSIS
CARLSBAD, CALIFORNIA
OCTOBER 1991
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1. INTRODUCTION
This is the ninth semi-annual report which describes the
sand survey and beach profile program performed at Carlsbad in
April, 1991. The following list includes all the semi-annual
surveys completed by Tekmarine at Carlsbad during the 1987-1991
period.
Report No.
1
2
3
4
5
6
7
8
9
Date of Survey
September 1987
January, April 1988
October 1988
April 1989
October 1989
April 1990
October 1990
April 1991
October 1991
Date of Report
February 1988
July 1988
January 1989
August 1989
November 1989
June 1991
June 1991
June 1991
March 1991
2. BACKGROUND INFORMATION
To aid in the understanding of this report, important
features of the coastal processes of the Carlsbad shoreline are
summarized below.
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1. The Carlsbad shoreline consists of two distinctly different
segments:
o The northern 1.5 miles (Buena Vista Lagoon to the Agua
Hedionda Lagoon intake jetties) is composed essentially
of sand beaches. In this reach, sand in the subaerial
and offshore profiles exists as a thin veneer underlain
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by cobble or rocky beds, with the thickness of this
sand veneer diminishing progressively to the south
along the reach.m
o The southern five miles (from Agua Hedionda to the
*! City's southern boundary) which consists essentially of
H cobble beaches. In this reach, the shoreline is
dominated by cobbles, while sand occurs in the offshore
•H profile generally below mean lower low water (MLLW).
^ The beach between the entrance and discharge jetties
off Agua Hedionda Lagoon remains sandy because of
periodic nourishment of fine sand from the lagoon
^ provided by dredging activities conducted by San Diego
ii Gas and Electric Company (SDG & E).
m 2. The beach profiles of Carlsbad, from the crest of the berm
m down to -30 ft (MLLW), are severely sand starved. A
sediment thickness survey performed by Tekmarine for the
_ U.S. Corps of Engineers (USACOE) over the entire Oceanside
; littoral cell revealed that both the narrowest beach width
^ and the leanest profile in the cell are found within
Carlsbad. For instance, the sand content in the subaerial
9 profile in Carlsbad is only about 15 cubic yards/foot
if (cy/ft) of shoreline. This may be compared with as much as
500 cy/ft in the Oceanside Harbor north fillet and about 100
m cy/ft at Del Mar, Solana Beach, and La Jolla (Tekmarine,
m 1988).
3. The shoreline positions in Carlsbad change seasonally by
amounts varying between 100 and 200 ft. The change in
* shoreline position tends to be small in the sandy profiles
in the northern reach, but large in the cobble profiles in
* the southern reach. The minimum change, amounting to about
gl 100 ft, occurs near Tamarack Avenue, where the rock is often
exposed in .the offshore profile.
4. In recent years, the beaches of Carlsbad experienced two
major impacts from extraordinary storms. One occurred
during the 1982-1983 winter season in which an unusually
** large number of severe storms with predominantly westerly
«l (rather than the northwesterly) approaches arrived on the
California coast. Coupled with the high sea level which has
m been attributed to the El Nino phenomenon, these storms
M caused considerable erosion to the southern California
beaches.
m^ 5. After the 1982-1983 winter storm season, in the northern
reach of the Carlsbad shoreline, the beach profiles were
slow to recover and the beach cycle featuring the alternate
^ summer accretion and winter erosion vanished altogether.
Mi This was attributed to the fact that considerable amounts of
sand and cobble had been removed from the shallow portion of
H the profile by the severe storms. In the cobble beaches of
— the southern reach, however, resumption of the seasonal
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beach cycle was noticed in 1986, about three years after the
1982-1983 winter season.
6. Another severe storm event occurred on January 18, 1988 when
waves of historical magnitude, with recorded deep-water wave
heights of 30 ft, were generated by a rapidly moving
extratropical storm. The maximum significant wave height
recorded by the nearshore wave array off Oceanside at that
time was 15.8 ft. Because the peak of the storm failed to
coincide with the high tide, damages on the beach property
were relatively modest in Carlsbad. However, the beaches
were eroded severely by the storm.
7. The January 1988 storm failed to extinguish the seasonal
beach cycle completely, although it did subdue its
amplitude. From the time of that major storm until 1990,
seasonal adjustments to the MLLW shoreline position were
modest due to mild winter wave conditions.
8. Deficiency of sand in the beach profiles is the single most
important factor characterizing the beach processes in
Carlsbad. The erosion impact of major storms tends to be
prolonged in the northern reach where sand is deficient in
the profile. In the southern reach, the profiles tend to
recover from storm damage with resiliency, as the profiles
contain considerable amounts of movable material.
9. Recent beach nourishment programs have been performed in the
vicinity of Agua Hedionda in March and April, 1988 (331,000
cy), and December 1990 - April 1991 (465,000 cy). The sand
was dredged from the Agua Hedionda Lagoon by San Diego Gas
and Electric Company (SDG & E) as part of their periodic
lagoon de-silting operations. Two additional beach
nourishment projects were undertaken by the U.S. Army corps
of Engineers from April through mid-June, 1989 (217,000 cy)
and in August 1990 (250,000 cy) during which sand was
dredged from the Oceanside Harbor entrances and discharged
at Tyson Street in Oceanside.
10. In the 1988 SDG & E beach nourishment program, fine sand from
the lagoon was placed behind a graded cobble dike between
the entrance and discharge jetties of Agua Hedionda Lagoon.
This new approach, modeled after the scheme proposed by
Tekmarine for the Batiquitos Lagoon Enhancement Project, was
successful in retaining sand on the beach. During the
several years since the sand placement, the artificially
constructed berm has remained essentially intact.
Conversely, much of the sand fill placed south of the Agua
Hedionda Lagoon entrance jetties was lost rapidly, because
in this area the lack of sufficient cobbles on the beach
prevented construction of an effective protective dike for
the nourished berm (Cahill, et al., 1989).
V
-11. The U.S. Army Corps of Engineers commenced operation of the
sand bypassing system at Oceanside Harbor in June 1989.m Since that time, a total of about 25,000 cubic yards of sand
•I has been delivered from the dredged entrance to the south
fillet area.
•p
m 12. Recently, the U.S. Army Corps of Engineers published the
shoreline erosion history for the Oceanside Littoral Cell
m for the period 1933-1989). The result shows a highly
contrasting pattern of shoreline changes between the
** northern half (north of Oceanside Harbor) and the southern
half of the cell. The northern half has generally accreted,
*• while the southern half has generally eroded. The shoreline
Ml erosion in the southern half of the cell has been most
severe at Carlsbad, averaging about one foot per year
« (Kadib, et al.. 1989).
m 3. RECENT BEACH NOURISHMENT OPERATIONS
m
,Q Between August 1990 and November 1991, the sand bypassing
j| system at Oceanside Harbor operated by the U.S. Army Corps of
Engineers was shut down to undergo major construction
jgj improvements. For this reason, only a small guantity of sand
bypassing (5,000 cy total) has occurred at Oceanside Harbor
** since the time of the last survey effort in April 1991.n
H No dredging of the navigation channels or the approaches to
" Oceanside Harbor has occurred since August 1990.
m
tg A major sand replenishment program was undertaken by the San
Diego Gas and Electric Company at Agua Hedionda during December
jg 1990 - April 1991 (W. Dyson, personal communication, 1991).
Similar to the dredging and beach replenishment project
* conducted in 1988 (Tekmarine, Inc., 1989; Cahill, et al., 1990),
a total of 465,000 cubic yards of fine sand was dredged from
* Agua Hedionda Lagoon and placed at three sites along the
** Carlsbad beachfront. The three locations of sand placement are
m shown in Figure 1 and listed below indicating the sand volumes
•« associated with each site.
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Buena Vista Lagoon
City of Carlsbad
50,000 CY
265,000 CY
Pacific Ocean
5,000 FT
SCALE
TOTAL PROJECT: 465,000 CY OF SAND DREDGED FROM AGUA HEDIONDA LAGOON
BY SAN DIEGO GAS AND ELECTRIC COMPANY
FIGURE i: BEACH REPLENISHMENT, DECEMBER 1990 - APRIL 1991
5
mm SAND REPLENISHMENT SITES AND VOLUMES
AGUA HEDIONDA LAGOON DREDGING
DECEMBER 1990 - APRIL 1991
o North of Tamarack Ave. 50,000 cubic yards
•I o Between Power Plant Intake
gj and Discharge 265,000
o South of Power Plant Discharge 100,000
— Total Replenishment Volume = 465,000 cubic yards
m The effect that this beach replenishment program had on the
H beaches in the vicinity of Carlsbad will be discussed in Section
5 of this report.
* 4. FIELD OPERATIONS
^ 4.1 Survey Procedures
M
m Figure 2 provides a schematic illustration of the procedures
Hi used for the sand survey and beach profile program. The
procedures employed in the October 1991 survey are consistent
^^ with those used in the previous surveys since September 1987.
These procedures have been designed to satisfy the accuracy and
quality control criteria stipulated by the U.S. Army Corps of
Engineers in support of the survey program for the Coast of
*1 California Storm and Tidal Waves Study.
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m Survey Accuracy Requirements
ii Survey Type Vertical Accuracy Horizontal Accuracy
Wading ± 0.1 ft +. 1.0 ft
J . Boat ± 0.5 ft + 10.0 ft.
* 4.2 Survey Stations
m
ip The geographical distribution of established survey range
m lines in the Carlsbad/Oceanside area is shown in Figure 3. The
location, date and types of surveys performed thus far for the
gf City of Carlsbad are summarized in Table 1. As shown therein,
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i I I I 1 1 t •
11 11 11 11 11 11 1 • I
WADING SURVEY
SWIMMER WITH EXTENDABLE ROD
RANGE TARGET
FATHOMETER SURVEY
INFLATABLE BOATWITH
FATHOMETER AND EOM REFLECTOR
-Hi
OVERLAP
SHORE SURVEYOR WITH
"ELECTRONIC DISTANCE METER (EDMI
RANGE LINE MONUMENT
RANGE TARGET
FIGURE 2: SURVEY METHODS
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CB-0720
A
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LEGEND:
RANGE LINE NUMBER
WADING SURVEY
WADING AND BOAT SURVEY
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1
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mm
m
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mm
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*
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fACIFIC OCIAH
FIGURE 3: LOCATION OF RANGE LINES
8
I J II t I I 1 11 11 11
TABLE 1A
LIST OF RANGE LINES, AZIMUTHS, MONUMENT ELEVATIONS, AND SURVEY DATES
SEPTEMBER 1987 - OCTOBER 1989
Range
LINE
CB-720
CB-730
CB-740
CB-750
CB-760
CB-780
CB-800
CB-820
CB-830
CB-840
CB-850
CB-860
CB-880
OS -900
OS -920
OS -930
OS -960
Azimuth
(MAGNETIC)
240
240
237
237
235
230
225
225
225
224
224
220
224
223
222
221
221
Monument
Elevation
(ft,MLLW)
12.78
53.26
70.46
33.10
21.09
62.01
18.41
16.5
16.9
19.4
45.63
11.10
21.30
17.52
12.03
13.12
20.4
September 1987
Wadinq Boat
9/21 9/21
9/29
9/29 9/29
9/29
9/21 9/22
9/29
9/22
9/29 9/29
9/22 9/22
9/29
9/30 9/29
9/30
9/29 9/29
9/22 9/22
9/30
9/22 9/22
9/30
January 1988 April 1988
Wadinq Boat Wadinq Boat
1/26 1/26 4/26 4/26
4/27
1/30 4/26 4/26
4/27
1/30 4/27
4/27
1/30 4/27
1/30 4/26 4/26
1/27 1/26 4/27
1/30 4/27
4/26 4/26
4/27
1/30 4/26 4/26
1/26 1/26 4/27
4/27
4/26 4/28
4/26
July 1988 October 1988
Uadinq Wadinq Boat
10/17 10/17
10/17
10/17 10/27
10/18
7/25 10/17 10/17
7/25 10/17 10/17
7/25 10/17
10/17
10/18
10/17 10/17
10/17
April 1989
Uadinq Boat
4/27 4/27
4/26
4/27 4/27
4/26
4/27 4/27
4/27 4/27
4/26
4/26
4/26
4/27 4/27
4/26
October
Wadinq
10/27
10/27
10/27
10/27
10/27
10/26
10/27
10/27
10/27
10/26
10/26
1989
Boat
10/26
10/26
10/26
10/26
10/26
Note:
1. Surveys sponsored by the Corps of Engineers, CCSTWS: 9/21-22/87, 1/26-27/88.
Surveys sponsored by Tekmarine, Inc.: 4/26-27/88, 7/25/88.
All other surveys sponsored by the City of Carlsbad.
2. Temporary monuments for Range Lines CB-820, CB-830, CB-840, and OS-960 are re-established on the beach for each survey. The elevation of the
beach point varies from survey to survey, and is inferred from a permanent monument on the backshore. The elevation shown is for the most recent
October 1991 survey.'
TABLE 1B
LIST OF RANGE LINES. AZIMUTHS, MONUMENT ELEVATIONS, AND SURVEY DATES
APRIL 1990 - OCTOBER 1991
Range
Line
CB-720
CB-730
CB-740
CB-750
CB-760
CB-780
CB-800
CB-820
CB-830
CB-840
CB-850
CB-860
CB-880
OS -900
OS -920
OS -930
OS -960
Azimuth
(MAGNETIC)
240
240
237
237
235
230
225
225
225
224
224
220
224
223
222
221
221
Monument
E levat ion
(ft,MLLW)
12.78
53.26
70.46
33.10
21.09
62.01
18.41
16.5
16.9
19.4
45.63
11.10
21.30
17.52
12.03
13.12
20.4
April 1990
Wadinq Boat
4/30 5/1
4/30
4/30 5/1
4/30
4/30 5/1
4/30 5/1
4/30
4/30
4/30
4/30 5/1
5/1
October 1990
Wading Boat
10/30 10/31
10/30
10/30 10/31
10/30
10/30 10/31
10/30 10/31
10/30
10/30
10/30
10/30 10/31
10/30
April 1991
Wading Boat
4/18 4/19
4/18
4/18 4/19
4/18
4/18 4/19
4/18 4/19
4/18
4/18
4/18
4/18 4/19
4/18
October
Wadinq
10/17
10/17
10/17
10/17
10/17
10/17
10/17
10/17
10/17
10/17
10/17
1991
Boat
10/18
10/18
10/18
10/18
10/18
Note:
1. These surveys sponsored by the City of Carlsbad.
2. Temporary monuments for Range Lines CB-820, CB-830, CB-840, OS-960 are re-established on the beach
for each survey. The elevation of the beach point varies from survey to survey, and is inferred
from a permanent monument on the backshore. The elevation shown is for the most recent October 1991
survey.
m the October 1991 surveys consisted of five long profiles (wading
in plus boat surveys) and six short profiles (wading surveys only).
m
The long profiles in which both wading and boat surveys were
^ performed in October 1991, are as follows:
"H OCTOBER 1991 LONG SURVEY PROFILES
m OS-930 South Oceanside, off Morse Street
— CB-830 Carlsbad, off Tamarack Street. Approximately 600
ft north of the north jetty of the Agua Hedionda
" Lagoon entrance.m
CB-820 Carlsbad, the public beach midway between the
•• entrance and discharge jetties of Agua Hedionda
jH Lagoon.
_ CB-760 Carlsbad, Encinas Creek Outlet.
"* CF-720 Carlsbad, approximately 800 ft south of the
Batiguitos Lagoon entrance.mm
During the survey operations, Tekmarine surveyors took notes
™^ on the state of the beaches at each range line and also
photographed the sand cover and features of interest. The
™ photographic documentation has been utilized in the analysis of
the beach survey data.
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m 5. SURVEY RESULTS
m
5.1 The Data
Survey data are presented in graphical format in the
^ appendices of this report, as follows:
*i Appendix A Wading Profiles
Appendix B Wading and Boat Profiles
m Appendix C Time History of MLLW Shoreline.
Results of data analysis are discussed in terras of profile
m changes, sediment volume, and shoreline trends.
•
m 5.2 Profile Changes
m
Comparison of profile data for the October 1990 - October
1991 period indicates that sand movement from the nearshore zonemto the beach has occurred. Evidence of beach sediment accretion
** at Carlsbad within the last year is particularly well pronouncedm
at Agua Hedionda (Profile CB-820, shown in Figure 4.A) and at
m Tamarack Avenue (Profile CB-830, shown in Figure 4.B), where the
•I previously described SDG & E dredging program deposited 465,000 cy
of sand on the adjacent beaches during early 1991. Similar
^1g| beach accretion exists throughout the city of Carlsbad (see
plotted profiles in Appendix A). In contrast to the general
accretion of profiles at Carlsbad, beach erosion is clearly
noted throughout the profiles in Oceanside, at Morse Avenue
* (Profile OS-930, shown in Figure 5.A) and at Oceanside Boulevard
gu
(Profile OS-960, shown in Figure 5.B).
5.3 Sediment Volume
Tabulation of beach volume for the time period spanning
April 1987 and October 1991 is shown in Table 2 and Table 3.
The former documents beach volumes above the MLLW datum, while
the latter identifies profile volume above the -30 ft (MLLW)
elevation.
Tables 2 and 3 indicate that volumetric changes during the
October 1990 - October 1991 comparison year were very small.
This was due to a relatively mild storm wave environment during
the October 1990 - April 1991 winter season coupled with the
onshore transport of nearshore sediments by long-period waves
during the summer of 1991.
12
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m
m
Elevation (ft-MLLW)
30
A. Line CB-820, Agua Hedionda - South
25 jr-
20 ^-
October 1991
October 1990
500 1000 1500 2000
Range (feet seaward of range line monument)
2500
Elevation Ift-MLLW)
30
B. Line CB-830, Tamarack Avenue
October 1991
October 1990
MLLW
1000 150C 2000
Range (feet seaward of range line monument)
2500
FIGURE 4: PROFILE ACCRETION NEAR AGUA HEDIONDA,
OCTOBER 1990 - OCTOBER 1991
13
m
m
11
m
m
m
m
Elevation (ft-MLLW)
30 •
A. Line OS-930, Morse Avenue
October 1991
October 1990
MLUV
500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 5COO
Range (feet seaward of range line monument)
m
m
m Elevation Ift-MLLW)
35
B. Line OS-960, Oceanside Boulevard
m
m
mm
nm
25 '—
m
m
mm
mm
m
20
15
10
5
0
-5
!
—
^_
-
—
L
—
-10 —
October 1991
October 1990
MLLtv
'00 200 300 400 500 600 700 800 900
Range (feet seaward of range line monument)
FIGURE 5: PROFILE EROSION IN OCEANSIDE,
OCTOBER 1990 - OCTOBER 1991
14
II 11 ft I IIII I I II II II 1 i 111 t 1 ft I ft I II t I ft 1 • 1
TABLE 2
VOLUME IN PROFILE ABOVE HL.LU (CY/LF)
RANGE APR 87
CB-720 81 .0
CB-730
CB-740
CB-750
CB-760 54.1
CB-780
CB-800 23.9
CB-820
CB-830
CB-840
CB-850
CB-860
CB-880
OS -900 39.5
OS -920
OS -930 67.7
OS -960
SEP 87
105.3
98.6
174.2
44.6
63.2
166.8
24.0
64.1
26.0
29.1
137.2
14.8
51.0
57.6
35.3
81.2
114.3
JAN 88
83.4
151.4
51.8
17.2
39.4
21.5
21.2
34.6
28.6
APR 88
80.6
86.2
153.6
38.7
51.5
151.9
20.8
55.4
34.1
39.5
126.6
8.8
31.8
31.4
14.4
52.9
112.3
JUL 88 OCT
83
143
55
158
53.7 54
22.6 27
29.9 26
138
44
68
131
88
.6
.8
.3
.8
.1
.7
.8
.9
.8
.1
.5
APR 89
83.9
149.4
58.3
151.9
47.8
30.5
33.4
128.5
42.9
67.2
131.1
OCT 89
81.9
153.1
55.1
166.0
50.5
46.3
22.4
130.9
51.6
75.0
137.9
APR 90
78.9
161.6
58.2
161.3
44.4
37.1
31.4
138.4
46.7
61.9
133.3
OCT 90
84.3
170.2
59.2
167.5
54.4
23.6
27.3
151.7
55.5
73.4
155.4
APR 91
83.0
164.9
54.2
151.6
66.2
29.9
15.5
135.9
41.4
67.6
149.9
OCT 91
92.9
172.7
64.5
163.9
71.8
34.2
37.3
169.9
60.8
74.5
155.1
Note: All volumes are measured from horizontal distance = 0.0 ft.
Permanent monuments for these locations do not exist for Profiles CB-820, CB-830, CB-840, and OS-960.
ft fti
TABLE 3
VOLUME IN PROFILE ABOVE -30 FT, HLLW (CY/LF)
RANGE APR 87 SEP 87 JAN 88 APR 88 JUL 88 OCT 88 APR 89 OCT 89 APR 90 OCT 90 APR 91 • OCT 91
C8-720 1141.7 1187.2 1150.3 1126.0
CB-730
CB-740
CB-750
1356.5 1290.3
1117.3 1106.5 1077.7 1074.4 1039.7 1095.7 1091.5
CB-760 1104.8 1096.9
CB-780
CB:800 1172.0 1165.5
1086.6 1111.9 1105.1 1098.8 1086.7 1073.1 1062.5
CB-820
CB-830
CB-840
CB-850
1126.5 1116.9
1037.1 1086.0
1352.8 1363.5
1085.5 1078.2 1061.8 1040.5 1038.3 1167.6 1128.1
1069.2 1061.0 1110.5 1080.1 9%.9 1072.3 1023.6
Oi CB-860
CB-880 1146.3 1120.2
OS-900 1054.9 1050.7 1028.4
OS-920
OS-930 1217.3 1193.7
OS-960
1187.7 1214.3 1212.9 1186.5 1250.3 1169.7 1199.8 1139.1
Note: All volumes are measured from horizontal distance = 0.0 ft.
Permanent monuments for these locations do not exist for Profiles CB-820, CB-830, CB-840, and OS-960.
^m Tables 4, 5, and 6 have been prepared to show the average
m sediment volume for the entire Carlsbad shoreline since
Ml Tekmarine began this comprehensive survey effort in September
1987. Tables 4, 5, and 6 present, respectively, the sediment
"^gl volume per average profile above MLLW, in the entire profile to
-30 ft (MLLW), and in the profile below MLLW.m,
m
Perhaps the most noteworthy finding of the beach volume
*> computations for the October 1991 survey is the fact that the
** beach volume above the MLLW datum is greater than at any time
m since the commencement of nearshore surveying by Tekmarine in
Ml September 1987. However, it must be kept in mind that the
increase in average beach volume above MLLW achieved during the
m last year was very small, averaging merely 8.6% of the October
1990 volume, as shown in Table 4. The gain in the profile
volume below MLLW was even smaller, being approximately 1%.m
When the entire profile above -30 ft (MLLW) is considered, the
* gain of profile volume during the October 1990 - October 1991
* period has been just 1.5%. This minor change is close to the
m survey error and too small to be considered significant.
H
Prior to the April 1990 survey, the sediment volume below^i
gl MLLW had been declining continuously since 1987, as shown in
Table 6. While the April 1991 survey indicated that this trend
had reversed, the survey data from October 1991 indicates the
second lowest sediment volume below MLLW that has been observed
1 since 1987. Future surveys are required to confirm the presentmtrend in sediment volume change in this elevation range.
m
m
,_ 5.4 Shoreline Changes
m
Figure 6 illustrates the history of shoreline changes during
^ the 1983 - 1991 period for all of the surveyed profiles. The
survey results of October 1991 indicate major seaward advance of
U
m
m 17
m
TABLE 4
" HISTORY OF AVERAGE SEDIMENT VOLUME IN THE PROFILES
m ABOVE MLLW
m Survey Average Sediment Volume Above
Date Mean Lower Low Water
" September 1987 92.02 cy/ft
April 1988 77.82
m October 1988 84.85
m April 1989 84.08
October 1989 88.25
m April 1990 86.65
— October 19'90 91.88
April 1991 85.27
m October 1991 99.78
*" Note: Includes 11 profiles
ni
m TABLE 5
HISTORY OF AVERAGE SEDIMENT VOLUME IN THE LONG PROFILES
m ABOVE -30 FT, MLLW
m Survey Average Sediment Volume in
Date Long Profile
™ September 1987 1,169.1 cy/ft
<* April 1988 1,143.5
October 1988 1,114.6
m April 1989 1,114.1
,g October 1989 1,108.3
April 1990 1,108.8
„, October 1990 1,072.5
— April 1991 1,121.7
m October 1991 1,089.0
** Note: Includes 5 profiles
«
m TABLE 6
0 HISTORY OF AVERAGE SEDIMENT VOLUME
BETWEEN 0 AND -30 FT, MLLW
m
m Survey Average Sediment Volumem Date Between 0 and -30 ft, MLLW
September 1987 1,085.6 cy/ft
* April 1988 1,080.6
m October 1988 1,056.8
April 1989 1,056.6
m October 1989 1,046.6
£ April 1990 1,052.7
October 1990 1,011.5
m April 1991 1,061.5
October 1991 1,021.4
Note: Includes 5 profiles
^[m is
mm k a
Shore Position: Line 05-960
Ocsonside Boulevord
Shore Position: Line CB-640
Acacia Avenue
Shor« Position: Line C8-760
Encinas Creek
Most; Aveo
Shore Position: Line CB-740
Poinsetdo Lone
<»•> i*»o
ore t'oiition I me ( H M.'ll
Ayuu Hc.liondu, M"i I1)Shore Position Line CB-720
Botiquilos Lagoon
Shore Position: Line CB-850
Pine Avenue
ore Position: Line CB- 780
Palomor Airpo>"l Hood
Legend
Vertical Axis is MLLW Shoreline Position.
Horizontal Axis is Year.
Large Scale Plots Included in Appendix C.
FIGURE 4: HISTORY OF MLLW SHORELINE POSITION
m
m
m the MLLW shoreline since the previous survey of April 1991. The
in average shoreline advance during this six month period was about
M 88 ft. Of the eleven profiles surveyed, only one (Oceanside
Boulevard, Profile OS-960) experienced shoreline retreat during
^^1
m this period. When compared with the survey of October 1990, the
shorelines of October 1991 indicate seaward advance throughout
the study region by an average distance of about 30 ft. Thism
average shoreline advance during the past year is significant,
• given shoreline retreat that averaged about 35 ft annually at
** the two Oceanside profiles (Oceanside Boulevard: Profile OS-960,
m and Morse Avenue: Profile OS-930). The average shoreline
m advance during the past year when considering only beach
profiles within the city of Carlsbad is about 44 ft.
^a
ii
By performing linear regression analysis on all the beach
' width data at each profile during the October 1988 - October
1991 time period, the trend in shoreline change can be
W determined for the latest three-year period. The dashed lines
'* superimposed on the shoreline position plots of Figure 6
U indicate the trend for the seasonal survey data. These plots
• are included at larger scale in Appendix C of this report. If
the trend is upward, seaward advance of the shoreline is
^ occurring. If the trend is downward, shoreline retreat is
evident. The magnitude of the on-going trend in shoreline
change is represented by the steepness of the inclined line. A
horizontal trend indicates no long-term change in shoreline
m position. As is evident, all of the survey profiles except
>* three are experiencing a long-term shoreline advance. A trend
• of erosion is evident at Oceanside Boulevard (OS-960), while the
•I shoreline is quasi-stable at Tamarack Avenue (CB-830) and Acacia
_ Avenue (CB-840).
m
m
m
m
m 20
M
m
m
6. CONCLUSIONS
n
|g There are two factors which normally exert major influence on
the beaches in the study region: wave climate and supply of sand.
.g A very moderate wave climate prevailed during the most recent study
period between October 1990 and October 1991, essentially making
^ it the fourth consecutive year of moderate wave action. Reflectingn
this situation, volumetric changes in the beach profiles during the
H recent one-year period remained modest. Namely, volumetric changes
(• between October 1990 and October 1991 averaged only about 9% above
_ MLLW, about 1% below MLLW, and about 2% combining both above and
^^£j below MLLW.
^ During the recent study period (October 1990 through October
1991) the Carlsbad shoreline experienced major replenishment of
^ sand when San Diego Gas & Electric Company placed a total ofK465,000 cubic yards of sand on the shoreline both north and south
ID of Agua Hedionda during December 1990 through April 1991. In this
M program, the shoreline as far as about 2,000 ft to the north and
about 1,000 ft to the south of the lagoon entrance was the
*^lg immediate recipient of the replenished sand.
' In contrast, supply of sand to the Oceanside shoreline during
the recent one-year period (October 1990 through October 1991)
H totaled a meager 5,000 cubic yards from the Oceanside sand
Hi™ bypassing system which had been under repair for most of this
•HI period. Dredging of the Oceanside harbor navigation channel, the
(H principal source of nourishment for the Oceanside beaches, did not
occur during this period. The last time this occurred was inW
^j -August 1990 when approximately 250,000 cubic yard was released on
the beach of South Oceanside, near Tyson Street.
m
M
Reflecting the impact of the SDG&E beach nourishment program
H during December 1990 through April 1991, the profiles along the
•* Carlsbad shoreline experienced general accretion. Progressively
_, larger amounts of accretion occurred in the profiles closer to the
m 21
m
m
m
• center of the beach nourishment. Also reflecting the impact of the
beach nourishment was the pattern of accretion in the profile:WHI volumetric gains in the accreted profiles in Carlsbad were
concentrated mainly above MLLW. In fact, the beach sediment volume
above MLLW in our survey data as of October 1991 was greater than
at any time since the semi-annual beach survey program was
" commenced in September 1987.m
m Reflecting the characteristic effect of the lack of
'iU artificial replenishment on the source-starved shoreline, on the
other hand, the beaches at South Oceanside were eroded during the
W^^ October 1990 - October 1991 comparison period. It is worthy of
note that erosion of the South Oceanside profiles did occur in
: spite of the moderate wave climate which prevailed throughout this
period and also in spite of the fact that these profiles had
1 received a benefit of 250,000 cubic yards of sand replenishment as_
™ recently as August 1990. These facts may well indicate a near-
H total dependance of these source-starved shoreline at South
id Oceanside on artificial replenishment.
m
^ The contrasting changes in beach volume between Carlsbad and
Oceanside profiles were also manifest in beach width. When
" compared with the survey of October 1990, the shorelines of October
1991 indicated seaward advance of about 44 ft within Carlsbad, but
H retreat of about 35 ft within South Oceanside. Of all the profiles
• surveyed in our program, only the Oceanside Boulevard (OS-960)
m shoreline revealed a distinct trend for erosion over the past
H several years. The shoreline at Tamarack Avenue (CB-830) and
Acacia Avenue (CB-840), both located immediately north of the Agua
^^^ . Hedionda entrance, appeared to be quasi-stable during this period.
All other shorelines in Carlsbad exhibited a trend of advance.
m
m
m
m
•\
m 22
m
m
m
m
REFERENCES
Hi^ Bisher, D., 1992, Project Manager, U.S. Army Corps of
Engineers, Los Angeles District, Oceanside Harbor By-Pass
System, Personal Communication.
*• Cahill, J., C. Butcher, and W. Dyson, 1989, "Beach Nourishment
With Fine Sand, Carlsbad, California", Coastal Zone '89,
*» Vol. 3, American Society of Civil Engineers, p. 2092-2103.
••
Dyson, W., 1991, Dredge Master for San Diego Gas and Electric
m Company.
m Kadib, A., S. Fine, and J. Ryan, 1989, "Coast of California
Storm and Tidal Waves Study—An Overview", Coastal Zone '89,m Vol. 1, American Society of Civil Engineers, p. 836-848.
m
Tekmarine, Inc., 1988, "Sand Thickness Survey Report, San Diego
m Region", Prepared for the U.S. Army Corps of Engineers, Los
— Angeles District, Report No. CCSTWS 88-5, 21 p.
_ Tekmarine, Inc., 1989, "Semi-Annual Beach Profile Surveys and
Analysis for October 1989", Tekmarine, Inc., Tech. Reportm TCN-192.
m
m
m
m
m
m
23
m
m
APPENDIX A
WADING PROFILES
OCTOBER 1991
m
m
m
m
m
m
Note:
m
m
m
m
r • •
Because numerous profiles exist for each survey site, twoplots of profile data are presented:
1) Historical profiles collected during the September1987 - October 1989 period, and
2) The most recent profiles used in the data analysis.
All the data is plotted at the same scale in order to
support the comparison of all the survey data.
ii ti if mm mm m.m mm m.m n mm ft I Bfl I I I
Elevation (ft-MLLW)
30
Line CB-720, Batiquitos Lagoon
25 —
20
15 —
10
5 —
0
-5
-10 —
October 1991
October 1990
MLLW
. 1 5 i i i i i i .1 . i ..i i i .. i i i i i i i i i i i i i i .1 . i i i i i i i i i i i i i i i i i i i \ i i i i
0 100 200 300 400 500 600 700 800 900 1000
Range (feet seaward of range line monument)
t j ii || II J ft i • J 11 i •t i ii i 11 11 11
Line CB720
30.
Batiquitos Lagoon OCT89
APRS9
OCT88
APR88
JAN88
SEP87
25.
20.
15.
10.
MLLW
I I I I I I I I I I 1 T | I I T T T T T IT
400. 500. 600. 700. 800.200. 300.
Range (feet seaward of range line monument)
900.
-5.
-0.
—5.
— 10.
1000.
. i . . ft J 1 • •* * • • • ' • • • • • • • • •• •• • * • • " *
Elevation (ft-MLLW)
75
Line CB-740, Poinsettia Lane
October 1990
0 100 200 300 400 500 600 700 800
Range (feet seaward of range line monument)
900 1000
ft I ft i ft ft I ft I ft 1 • • * " * *ft 1 ft i ft i II • • •
Line CB740
75.
Poinsettia Lane OCT89
APR89
OCT88
APR88
JAN88
SEP87
0.
I I
200.300. 400. 500. 600. 700. 800.
Range (feet seaward of range line monument)
' T900.1000.
II i I i i ft 1 » *
II I i i I
Elevation (ft-MLLW)
30
25
20 —
15 —
10
Line CB-760, Encinas Creek Outlet
0
-5
-10 —
-15
October 1991
October 1990
0 100 200 300 400 500 600 700 800
Range (feet seaward of range line monument)
900 1000
ii • I II »-.-:•I II • I » *
Line CB760
30.
i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i
Encinas Creek OCT89
APR89
OCT88
APR88
JAN88
SEP87
25.
20.
15.
-10.
MLLW
i I '
800.
-5.
-o.
—5.
—10.
i i | i i i r
900. 1000.
15.
Range (feet seaward of range line monument)
ft I I M ft. fl mm mm ** •' * a »II •• II •! » * »*
Elevation (ft-MLLW)
65
Line CB-780, Palomar Airport Road
60
55
50
45
40
35
30
25
20
15
10
5
0
-5
-10
-15
October 1991
October 1990
I I I I I I I I I I I I I I I I I I I I I I I ! I I I I I ! I I ! I I I I I I I I
MLLW
0 100 200 300 400 500 600 700 800
Range (feet seaward of range line monument)
900 1000
Line CB780
Palomor Airport Road
OCT88
APR88
SEP87
0.
i i i i
100. 200.400. 500. 600. 700. 800.
Range (feet seaward of range line monument)
900.1000.
ft I ft i ft I ft i ft I * « * aj t i mi 11 •if ftl II i i •« B1
Elevation (ft-MLLW)
30
25 —
20
15
10
Line. CB-820, Agua Hedionda - South
0
-5
-10
-15
October 1991
October 1990
0 100 200 300 400 500 600 700 800
Range (feet seaward of range line monument)
900 1000
ii mm mm mm m*I 1 I 1 i • 1
Line CB820
30.
Agua Hedionda OCT89
APR89
OCT88
APR88
JAN8S
SEP87
-15
25.
20.
15.
-10.
MLLW
-5.
-0.
—5.
— 10.
0.100.
Ill | I I
500.
' J600.
I i i
700.
-15.
300. 400. 500. 600. 700. 800.
Range (feet seaward of range line monument)
900.1000.
J i I ft I i 1 I i I 1 I 1 I I » • • >II II
Elevation (ft-MLLW)
30
Line CB-830, Tamarack Avenue
25 —
20 —
15 \-
10
5 —
0 —
-5 —
-10 —
October 1991
October 1990
-15
MLLW
0 100 200 300 400 500 600 700 800
Range (feet seaward of range line monument)
900 1000
I ft I ft 1 • i , I II ft i ft • ft I •• ft 1 ft J II II 1 i »
Line CB830
Tamarack Avenue
-15
300. 400. 500. 600. 700. 800.
Range (feet seaward of range line monument)
I I T I
900. 1000.
ft i ft i ft I ft Jft I ft! II II • •i 1 ft .4 * i 11 • « » « •
Elevation (ft-MLLW)
30
Line CB-840, Acacia Avenue
25
20
15
10
0
-5
-10
October 1991
October 1990
MLLW
. -I C I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I- I I I I I I I I I I I I I I
0 100 200 300 400 500 600 700 800 900 1000
Range (feet seaward of range line monument)
i • • • i i i i t • • i • •
Line CB840
Acacia Avenue OCT89
APR89
OCT88
APR88
JAN88
SEP87
I I I I I I I I ! I I I I I I I 1 I I I I I I I-15
0.
I I I I I I I I I I I I
800. 900. 1000.
Range (feet seaward of range line monument)
fc i II i • II • • 11 • I i *
Elevation (ft-MLLW)
50
Line CB-850, Pine Avenue
40
October 1991
October 1990
i i i i i i i i i i i i i i i i i i i i i i i i i i
0 100 200 300 400 500 600 700 800
Range (feet seaward of range line monument)
900 1000
11 mm II II II •
Line CB850
OCT89
APR89
OCT88
APR88
SEP87
15.
200. 300. 400. 500. 600. 700. 800.
Range (feet seaward of range line monument)
1000.
ft i ft I • i • • • I 1 1 I 'II II II ft 1 II • I i I •
Elevation (ft-MLLW)
30
Line CB —880, Buena Vista Lagoon
25 —
20
15
10
0
-5
-10
October 1991
October 1990
MLLW
5 I I I I I I i I I I I I I I I I I I L_J I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
0 100 200 300 400 500 600 700 800 900 1000
Range (feet seaward of range line monument)
ft I I I 1 I I I I I I I I• I • I 11 *I II 11 *
Line CB880
30.30.
Buena Vista Lagoon OCT89
APR89
OCT88
APR88
JAN88
SEP87
-15.
200.
i I
300.400.500. 600.
i '
700.
i i I
800.
Range (feet seaward of range line monument)
25.
20.
15.
-10.
MLLW
-5.
-0.
—5.
— 10.
900. 1000.
II 1 J 11 II ft II II II II 11 II If
Elevation (ft-MLLW)
30
Line OS-930, Morse Avenue
25 —
20
15
10
0
-5
-10
15
October 1991
October 1990
MLLW
0 100 200 300 400 500 600 700 800
Range (feet seaward of range line monument)
900 1000
ft J fti 1i ft I II m.M ft i • 1 ft 1 ft 1 ft I ft i * * »fc J B J
Line OS930
30.
OCT89
APR89
OCT88
APR88
SEP87
-15.
o.100. 200. 300. 400. 500. 600. 700. 800.
Range (feet seaward of range line monument)
900. 1000.
II • i •i m* ii i i •«
Elevation (ft-MLLW)
35
Line OS-960, Oceanside Boulevard
30
25
20
15
10 —
5
0
-5
-10 —
October 1991
October 1990
MLLW
. -\ 5 i i i i i I i i i.i I i i i i i i i i i i L_J \ i I i i i i i i i i i i i i i i i i. i i i i i i i. i
0 100 200 300 400 . 500 600 700 800 900 1000
Range (feet seaward of range line monument)
I i 11 I i ft j if II II
Line OS960
35 35.
Oceanside Boulevard OCT89
APR89
OCT88
APR88
SEP87
-15.
MLLW
0.100.
I I I I I I I I i I I
200. 300. 400 500.i r600.
n i i i i i r
700. 800.
30.
25.
20.
15.
-10.
-5.
-O.
— 10.
-'-15.
900. 1000.
Range (feel seaward of range line monument)
m
m
APPENDIX B
WADING AND BOAT PROFILES
OCTOBER 1991
m
m
KM Note:
Because numerous profiles exist for each survey site, two
w plots of profile data are presented:
m
1) Historical profiles collected during the September
m 1987 - October 1989 period, and
gl
2) The most recent profiles used in the data analysis.
All the data is plotted at the same scale in order to
I support the comparison of all the survey data.
m
i i i i I i • i i i t i i i i i i i f i i i 11 • i
Elevation (ft-MLLW)
30 r:
Line CB-720, Batiquitos Lagoon
October 1991
October 1990
0 500 1000 1500 2000
Range (feet seaward of range line monument)
2500 3000
ti ml "*
Line CB720
30.-30.
25.
20.
15.
10.
-5.
0.
-5.
— 10.
— 15.
r-20.
— 25.
•30.
—35.
— 40.
— 45.
-50.
25.-
2Q.-
5--:
c
.2 -is.-
LJ
-25.-,
-30.-
-35.
-40.
-45.
-50.
Batiquitos Lagoon OCT89
APR89
MLLW
\ i i
0.I i ' i500.1000.
T |
1500.
T I I I
2000.
' i i r
2500.
Range (feet seaward of range line monument)
3000.
j i i ft m i t § i ii 11 ii ft * «
Elevation (ft-MLLW)
30
Line CB-760, Encinas Creek Outlet
October 1991
October 1990
0 500 1000 1500 2000 2500
Range (feet seaward of range line monument)
3000
Line CB760
30.-JO.
25.
20.
15.
10.
5.
0.
r-5.
25.-
15.-:
2 -5.^
c
O _i^^.— 10.
UJ
-25-
-30.-
-35.
-40.
-45.
-50.
Encinas Creek OCT89
APR89
OCT88
SEP87
MLLW
1-20.
25.
F— 30.
•35.
--4Q.
'—45.
-50.
6.
i i | i i i i I I i i i | i i i i i i i
500. 1000. 1500. 2000.
Range (feet seaward of range line monument)
i i i r
2500.3000.
ft I i J 1 ft I ft I »
* * "
Bfl
Elevation
30
(ft-MLLW)Line CB-820, Agua Hedionda - South
October 1991
October 1990
0 500 1000 1500 2000
Range (feet seaward of range line monument)
2500 3000
i i ti §i II t1 11 1 i
Line CB820
30.:
25.:
20-
15.-
30.
25.
20.
15.
10.
5.
Agua Hedionda
5-t
o
UJ
-20.-
-25.-
-30.
-35.
-40.
-45.
-50
OCT89
APR89
OCT88
APR88
SEP87
MLLW
— 15.
~25.
— 45.
-50.
0.500.1000.
I r
1500.
I
2000.2500.3000.
Range (feet seaward of range line monument)
II t I II i i 1 »* *
Elevation (ft-MLLW)
30
Line CB-830, Tamarack Avenue
October 1991
October 1990
0 500 1000 1500 2000
Range (feet seaward of range line monument)
2500 3000
ft i ft i * 1 fti ft I KJ 11 * mm
Line CB830
Tamarack Avenue OCT89
APR89
— • — •— OCTSo
JAN88
--- SEP87
i i i i f i i i i i i i i 7 i i r i
0.3000.
Range (feet seaward of range line monument)
I, 1 k i ft I ft I fti ii ii i i 11 • a
Elevation (ft-MLLW)
30
Line OS—930, Morse Avenue
October 1991
October 1990
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Range (feet seaward of range line monument)
5000 5500 6000
II ft I ft i * •ill 1 **ft J
Line OS930
OCT89
APR89
OCT88
APR88
SEP87
r i i | ri i rj IT ir \ ii i ijr r i T | T i r i \
1000. 1500. 2000. 2500. 3000. 3500. 4000.4500. 5000. "*5$00.
Range (feet seaward of range line monument)
-50.
6000.
APPENDIX C
TIME HISTORY OF MLLW SHORELINE
OCTOBER 1991
m
m
Note;
Dashed line on each plot indicates the trend of shoreline
position change during the October 1988 - October 1991
period as determined by linear regression. Upward line
inclination indicates shoreline advance, downward line
inclination indicates shoreline retreat.
m
m
m
m
Shoreline Position, ft
600
500
400
300
200
100 —
\_L
Shore Position: Line CB-720
Batiquitos Lagoon
_L
1983 1984 1985 1986 1987 1988
Year
1989 1990 1991 1992
m
m
m
m
m
m
m
m
Shoreline Position, ft
600
500
400
300
200 '
100 —
Shore Position: Line CB —740
Poinsettia Lane
-I,,. __J—^j. !_._—!..__' L '._. '..___'
1983 1984 1985 1986 1987 1988
Year
1989 1990 1991 1992
m
m
m
a
m
a Shoreline Position, ft
600
m
m
m
m
m
m
500
400
300
200
100 (—
Shore Position: Line CB-760
Encinas Creek
Year
Shoreline Position, ft
600
m
m
m
—
m
at
500
400
300
200
100 |—
Shore Position: Line CB-780
Palomar Airport Road
j—'—'—'—* * • i i i_-> 1 1 L r . |
.985 ,986 ,987 1988
Year
m
m
m
m
m
m
m
m
m
Shoreline Position, ft
600
500
400
300
200
100 f—
0 L_i—i—,—L , . , i , , | i
Shore Position: Line CB-820
Agua Hedionda, North
-J ' 1 1 L- I |.
1983 ,984 ,985 ,986 1989 ,990 199, 1992
Year
II
m
m
m
Shoreline Position, ft
600
500
400
300
200
100
Shore Position: Line CB —830
Tamarack Avenue
1983 ,984 1991 1992
•I
*
g
1i
m
m
m
m
m
mm
m
m
m
Shoreline Position, ft
600
50°
400
300
200 h-
100
Shore Position: Line CB-840
Acacia Avenue
°'9°r^;^r^r^^^^r^^^992
Year
Shoreline Position, ft
600
500
400
300
20°
Shore Position: Line CB-850
Pine Avenue
-J 1 1 l__L _L _L-J 1 li|.
1963 "8< '985 "86 '»' '« •«» -3,0 „„ ,992
Year
m
m
m
m
m
m
mm
m
m
m
m,
m
Shoreline Posifion, ft
600
500
400
300
200
100 f—
Shore Position: Line CB-880
Buena Vista Lagoon
_L _L _L I _L _L J__L
1983 1984 1985 1986 1987 1988
Year
1989 1990 1991 1992
Shoreline Posifion, ft
600
500
400
300
200 f—
100 p-
Shore Position: Line OS-930
Morse Avenue
_L
'983 1984 1985 ,986 1987 ,988
Year
1989 1990 1991 1992
m
m
Shoreline Position, ft
600
m
m
m
m
m
m
500
400
300
200
100 |—
Shore Position: Line OS-960
Oceanside Boulevard
Year
Hi
m
m
m
1i
m.a
m
m
m
mm