TIME-SERIES STUDY OF SANDING IN VENTURA
HARBOR, CALIFORNIA
Mario Edmundo Carneiro Vieira
iry
Naval Postgraauate Scnooi
Monterey, California 93940
Report Number NPS-58ViTh7^032
NAVAL POSTGRADUATE SCHOOL
Monterey, California
THESIS
TIME-SERIES STUDY OF SANDING
IN VENTURA HARBOR, CALIFORNIA
by
Mario Edmundo Carneiro Vieira
March 197^
Thesis
Advisor: W.C. The
jmpson
Prepared for:
Fleet Numerical Weather Central
Monterey, California 939^0
kppnove.d fo>i pubtic tieXiuibz; di&tnjJbuZion untimcte.d.
T1608
DUDLEY KNOX LIBRARY
NAVAL POSTGRADUATE SCHOOL
MONTEREY. CALIFORNIA 93940
NAVAL POSTGRADUATE SCHOOL
Monterey, California
Rear Admiral Mason Freeman Jack R. Borsting
Superintendent Provost
This thesis was prepared in conjunction with research
supported in part by the Fleet Numerical Weather Central,
Monterey, California 939^0 under Project Order 3-0011.
Reproduction of all or part of this report is authorized
Released as a
Technical Report by:
Time-Series Study of Sanding
in Ventura Harbor, California
by
Mario Edmundo Carneiro Vieira
Lieutenant Commander, Portuguese Navy
Submitted in partial fulfillment of the
requirements for the degree of
MASTER OF SCIENCE IN OCEANOGRAPHY
from the
NAVAL POSTGRADUATE SCHOOL
March 197^
UNCLASSIFIED
SECURITY CLASSIFICATION OF THIS PAGE (When Data Entered)
DUDLEY KNOX LIBRARY
NAVAL K3STGRADUATE SCHOOL
MONTEREY, CALlfCMA ■•,
REPORT DOCUMENTATION PAGE
READ INSTRUCTIONS
BEFORE COMPLETING FORM
1. REPORT NUMBER
NPS-58ViTh7^032
2. GOVT ACCESSION NO
3. RECIPIENT'S CATALOG NUMBER
4. TITLE (and Subtitle)
Time-Series Study of Sanding in Ventura
Harbor, California
5. TYPE OF REPORT a PERIOD COVERED
Master's Thesis Report
2 July 1973-29 March 1974
6. PERFORMING ORG. REPORT NUMBER
7. authors;
Mario E.C. Vieira in conjunction with
Warren C. Thompson
8 CONTRACT OR GRANT NUMBERS;
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Naval Postgraduate School
Monterey, California 93940
10. PROGRAM ELEMENT. PROJECT, TASK
AREA ft WORK UNIT NUMBERS
Project Order 3-0011
11. CONTROLLING OFFICE NAME AND ADDRESS
Fleet Numerical Weather Central
Monterey, California 93940
12. REPORT DATE
March 1974
13. NUMBER OF PAGES
113
U. MONITORING AGENCY NAME ft AODRESSf// di He tent from Controlling Oltlce)
15. SECURITY CLASS, (ot thle riport)
Unclassified
15a. DECLASSIFICATION/DOWNGRADING
SCHEDULE
16. DISTRIBUTION STATEMENT (of thle Report)
Approved for public release; distribution unlimited.
17. DISTRIBUTION STATEMENT (of the abetract entered In Block 20, If different from Report)
18. SUPPLEMENTARY NOTES
19. KEY WORDS (Continue on reveree tide It nacaaaary end Identity by block number)
Harbor sanding
Seasonal shoaling
Sand transport mechanisms
20. ABSTRACT (Continue on reveree eldm It neceeemry and Identity by block number)
An analysis of sand accumulation was carried out in the
entrance channel of Ventura Harbor based on 44 quasi-monthly
sounding surveys made over the four-year period from January 1965
to January 1969. The accumulation was found to follow a marked
seasonal pattern of little or no deposition in summer (May to
October) and maximum deposition in winter (between November and
March). The sand mass, which assumed a characteristic slope
DD ,K5a 1473
(Page 1)
EDITION OF 1 NOV 65 IS OBSOLETE
S/N 0102-014-6601 |
UNCLASSIFIED
SECURITY CLASSIFICATION OF THIS PAGE (When Date gntered)
UNCLASSIFIED
VlC-UWITy CLASSIFICATION OF THIS P AQE(Wh»n Data Entarad)
(20. ABSTRACT continued)
depending upon wave exposure, accumulated in greatest amount just
inside the seaward end of the North Jetty around which the sand
is supplied by downcoast littoral drift. The amount of sand
trapped by the harbor averaged 137,000 cubic yards per year, or
one-third of the estimated net annual littoral drift along this
coastal sector. Waves are the principal vehicle for sand
transport into the inlet as indicated by the close correlation
found between the seasonal rates of accumulation and the seasonal
wave regime, and from dynamical consideration of the tidal
current through the entrance channel.
DD Form 1473 (BACK) n..n: .CCTDTrn
1 Jan 73 UNCLASSIFIED
S/N 0102-014-6601 SECURITY CLASSIFICATION OF THIS PAGE(T»Ti»n D.r. Bnlarad)
ABSTRACT
An analysis of sand accumulation was carried out in
the entrance channel of Ventura Harbor based on 44 quasi-
monthly sounding surveys made over the four-year period from
January 1965 to January 1969 . The accumulation was found
to follow a marked seasonal pattern of little or no depo-
sition in summer (May to October) and maximum deposition
in winter (between November and March). The sand mass,
which assumed a characteristic slope depending upon wave
exposure, accumulated in greatest amount just inside the
seaward end of the North Jetty around which the sand is
supplied by downcoast littoral drift. The amount of sand
trapped by the harbor averaged 137,000 cubic yards per
year, or one-third of the estimated net annual littoral
drift along this coastal sector. Waves are the principal
vehicle for sand transport into the inlet as indicated by
the close correlation found between the seasonal rates of
accumulation and the seasonal wave regime, and from dynami-
cal consideration of the tidal current through the entrance
channel.
TABLE OF CONTENTS
I. INTRODUCTION
A. THE MARINA 8
B. BACKGROUND 8
1. Physiography of the Area
2. Wave Exposure 11
3. Littoral Drift 11
C. HISTORY 13
II. OBJECTIVES 15
III. THE SOUNDING DATA 16
IV. ANALYSIS OP THE FILLING 19
A. SEASONAL DEPENDENCY 21
B. SPATIAL DEPENDENCY 29
1. Volume Changes 29
a. Transverse Sections 29
b. Longitudinal Sections 36
2. Channel Migration and Depth Change 42
3. Contour Migration 49
V. INTERPRETATION 55
A. THE SAND SUPPLY 55
B. DYNAMIC EQUILIBRIUM CONSIDERATIONS 56
C. THE MECHANISM 57
LIST OF REFERENCES 63
APPENDIX 64
INITIAL DISTRIBUTION LIST 109
LIST OF TABLES
Table
I. Survey and Dredging Dates 18
II. Total Sand Fill for the Inlet per
Dredging Year 28
III. Dredged Volumes 28
IV. Rates of Sand Fill per Dredging Year
for the Transverse Sections 41
V. Rates of Sand Fill per Dredging Year
for the Longitudinal Sections 4l
VI. Southward Migration of the Channel Axis
in Each Dredging Year for Range Lines
0 ft, 200 ft, 500 ft, 800 ft ^8
VII. Decrease in Channel Axis Depth in Each
Dredging Year for Range Lines 0 ft,
200 ft, 500 ft, 800 ft 48
LIST OF ILLUSTRATIONS
Figure
1. Ventura Marina 9
2. Ventura Marina and Vicinity 1:
3. Wave Exposure of Ventura Marina Entrance 12
4. Ventura Marina Inlet Sounding Grid and Sections 20
5. Sand Volume Changes Between Successive
Surveys for the Inlet 22
6. Cumulative Sand Volume Changes Between
Successive Surveys for the Inlet 23
7. Daily Sand Volume Changes Between
Surveys for the Inlet 25
8. Histogram of Daily Sand Volume Change
Between Surveys for the Inlet 26
9. Cumulative Distribution of Daily Sand
Volume Change for the Inlet 27
10. Volume Changes Between Successive
Surveys. Transverse Sections 31
11. Cumulative Volume Changes - Transverse Section 1 -- 32
12. Cumulative Volume Changes - Transverse Section 3 — 33
13. Cumulative Volume Changes - Transverse Section 5 — 3^
14. Cumulative Volume Changes - Transverse Section 8 — 35
15. Cumulative Volume Changes - Longitudinal
Section 2 37
16. Cumulative Volume Changes - Longitudinal
Section 5 38
17. Cumulative Volume Changes - Longitudinal
Section 8 39
Figure
18. Cumulative Volume Changes - Longitudinal
Section 11 40
19. Channel Location and Depth - 0 ft
Range Line Transect 43
20. Channel Location and Depth - 200 ft
Range Line Transect 44
21. Channel Location and Depth - 500 ft
Range Line Transect 45
22. Channel Location and Depth - 800 ft
Range Line Transect 46
23. Position of the -20 ft contour from surveys
in 1967-68 50
24. Selected Contours - 200 ft Range Line Transect — 53
25. Selected Contours - 500 ft Range Line Transect — 5^
26. Frequency of Wave Occurrence 60
27. Relative Wave Power 61
ACKNOWLEDGMENT
I wish to express my gratitude tc Dr. Warren C. Thompson
for his precious, dedicated and patient advice during the
preparation of this thesis. It is of interest to note
that the Oceanographic Services, Inc. (Phase II) report
(1965), from which significant background information was
obtained, was prepared by Professor Thompson.
I also want to thank the Ventura Port District authori-
ties, in the person of the General Manager Mr. K. C. Klinger,
who made the original sounding records available, provided
background information on the harbor and was such a gracious
host during a visit to the harbor. To Mr. Charles Holt of
the Los Angeles District Corps of Engineers go my thanks
for making the files of sounding surveys available for
this study and providing pertinent reports on loan.
To my wife Jane I extend my appreciation for the
encouragement and loving support which made it all so
much easier.
I. INTRODUCTION
A. THE MARINA
Ventura Marina is a man-made harbor on the coast of
California, 65 miles to the northwest of the city of Los
Angeles. The harbor consists of three interior basins
and a network of keys. The entrance channel, which is the
specific concern of this thesis, is confined by two rubble-
mound jetties and has a spending beach on the south side,
designed to absorb the energy of the incoming waves (Figures
1 and 2).
B. BACKGROUND
1 . Physiography of the Area
Ventura Harbor lies on the flat coast of an embay-
ment contained between the Ventura River delta to the north
and the Santa Clara River delta to the south. The Santa
Clara river empties about one half mile south of the
marina entrance (Figure 2).
The low lying plain on which the harbor was exca-
vated extends about one half mile inland to the base of
a 75-foot cliff. This is an old sea cliff, seaward from
which the plain has been built by littoral processes in
historic time.
This coastal area has been very dynamic. The
Santa Clara River in some years transports great quantities
of sediment and builds out its delta. This acts basically
>.
>
cti
CONTOURS IN FATHOMS
0
SCALE t=
3000
6000
=3 FEET
*•■ Clara *
Figure 2: Ventura Marina and Vicinity
10
as a groin which disturbs the southward flowing littoral
drift, resulting in a generally prograding shoreline in the
embayment . The seaward advance of this shore between the
river discharges has been, however, counteracted by erosion
during years of little runoff (Oceanographic Services,
Inc. , (Phase II), 1965) .
2. Wave Exposure
Ventura Harbor is subject to a reduced exposure to
swell from the open ocean since it is sheltered by the coast
and by the Santa Barbara Channel Islands (Figure 3). The
latter act as a filter, allowing only narrow directional
bands of approach from the west, southwest, and south. The
fetch in these directions is unlimited and permits the
generation of large wind waves. Fetches in nearly all other
directions outside of these three bands are under 20 miles
and prohibit the growth of large seas.
Refraction diagrams (Corps of Engineers, 1970) show
that the marina is situated in an area of strong convergence
for a wide spectrum of westerly waves, which are the domi-
nant waves at the marina opening.
3. Littoral Drift
From statistical wave studies (Corps of Engineers,
1970) , it was ascertained that the most important waves
affecting Ventura Marina throughout the year, in terms of
energy and frequency of occurrence, predominate from the
sector 250° to 280°. This results, as summarized in the
11
CD
o
C
ctf
fn
4^
c
w
CD
^-^
c
o
•H
t^
h
cr\
Ctf rH
S
01
to
?H
in
3
CD
-P
CD
c
C
CD
•H
>
bO
C
l*H
w
o
<W
CD
o
m
3
CO
co
a
o
u
a
o
X
o
w
s
CD
o
>
u
a
Cm
^
^>
on
CD
M
hO
•H
12
Oceanographic Services, Inc., report (Phase II) of 1965, in
a net annual downcoast (Southerly) littoral drift in this
area. The rate of sediment transport has been estimated at
iJOO, 000 cubic yards per year in this region of the coast
(Department of Water Resources, 1969).
C. HISTORY
Ventura Marina, designed by John A. Blume and Associates
of San Francisco, was excavated out of sandy soil and opened
to use in March 1963 after completion of the jetties and
dredging of the entrance channel. The keys were excavated
later and opened in January 196*5.
Since its inauguration the harbor has been plagued with
two hazardous conditions; namely, shoaling and resultant
severe wave breaking in the entrance channel. This situ-
ation prompted a series of dredgings, to a design depth of
-20 ft Mean Lower Low Water (MLLW) , which have been carried
out once a year since 1964 by the Shellmaker Company. The
spoil was placed on the beach south of the South Jetty.
In January and February of 1969, heavy flooding of the
Santa Clara River breached the north bank and diverted the
river partially through Ventura harbor, causing great
damage in the marina and surrounding area. The rehabilita-
tion program that followed provided for dredging of the harbor
basins and entrance channel.
An intensive review of the shoaling and hazardous wave
conditions of Ventura Marina was undertaken by Oceanographic
Services, Inc., which, at the end of a two-stage study
13
recommended in 1965 the construction of an offshore break-
water. This was designed to shelter the harbor entrance from
the dominant westerly waves, creating at the same time an
area of quiet water in its lee on the upcoast side of the
North Jetty which would act as a sand trap for the sediment
moving downcoast. Following authorization by the Congress
for modification of the harbor, the U. S. Army Corps of
Engineers published in 1970 the design memorandum with the
plans and specifications for the construction of the off-
shore breakwater and the surveys and studies made in
connection with that project (Corps of Engineers, 1970).
The breakwater was completed in 1972.
14
II. OBJECTIVES
With the purpose of monitoring the shoaling situation
in the entrance to the marina, the Ventura Port District has
carried out since 1964 a program of quasi-monthly soundings
of the inlet. These sounding surveys constitute an excellent
time series of the shoaling history. A series of these
surveys was selected for study in this thesis, starting in
January 1965 just after the keys were opened and the interior
configuration of the harbor was completed, and ending in
January 1969 just prior to the heavy floods which ravaged
the marina. The design of the harbor remained static during
this four-year period.
The objectives of this thesis are: (1) the determination
of the space-time pattern of sand accumulation in the
entrance, or inlet, of Ventura Marina over the period from
January 1965 to January 1969, between the opening of the
keys and the 1969 floods; and (2) the explanation for the
pattern .
15
III. THE SOUNDING DATA
The soundings of the harbor entrance, made under the
direction of the Harbormaster of the Ventura Port District,
constitute the basic data for this study. The soundings
cover the outer part of the main channel connecting the
inner harbor with the ocean, which is the area of serious
shoaling and wave conditions. No soundings were made in
the area between the main channel and the spending beach.
As will be discussed, this area appears to behave indepen-
dently of the main channel.
The surveys were carried out at quasi-monthly intervals
using a small boat in good sea conditions at any stage of
the tide. The soundings were taken using a lead line in
earlier work and a fathometer with visual indicator later.
The precision of these uncorrected soundings is estimated
to be ± 0.2 5 ft.
The survey procedure involved the use of permanently
fixed range marks on the North Jetty at 100 ft intervals.
A marked tack-line was stretched taut from the boat
perpendicularly to a man on the jetty at every range mark.
The marks on this tack-line were 50 and 100 feet apart and
they determined the location of the sounding stations.
Where this method was not viable, namely outside the
entrance, bearings were taken and distances estimated. The
pattern of the soundings is shown in the charts in the
Appendix .
16
The soundings from each survey were corrected by the
Ventura Port District for the transducer depth when appro-
priate and for the tide stage at 15-minute intervals relative
to a floating gauge in the harbor, and were plotted in chart
form with reference to Mean Lower Low Water. These charts
were used in all of the work in this thesis related to
bathymetry .
The precision obtained by these corrected soundings was
considered insufficient for the computerized volumetric
calculations presented in this thesis. For this purpose the
original sounding data were reduced to MLLW using tide
corrections to 0.1 ft derived from the tide tables (National
Ocean Survey). The precision of these corrected soundings
is estimated to be I 0.3 ft.
The dates of the 44 sounding surveys utilized and of the
four annual entrance dredgings are listed in Table I.
Copies of the working charts, drawn by the Ventura Port
District and contoured by the writer at 2 ft intervals, are
presented in chronological order in the Appendix.
17
TABLE I
SURVEY AND DREDGING DATES
Sounding series
28 January 1965
11 February 1965
12 April 1965
Entrance dredged 24 May - 9 June 1965
Sounding series
10 June 1965
9 July 1965
11 August 1965
10 September 1965
13 October 1965
12 November 1965
3 December 1965
5 January 19 6 6
11 February 1966
4 March 1966
24 March 1966
15 April 1966
Entrance dredged 2 - 14 May 1966
Sounding series
17 May 1966
6 June 1966
18 July 1966
19 August 1966
21 September 1966
21 October 1966
23 November 1966
28 December 1966
19 January 1967
8 February 1967
3 March 1967
26 April 1967
9 May 1967
Entrance dredged 19 May - 6 June 1967
Sounding series
2 June 1967
8 September 1967
17 October 1967
29 November 1967
27 December 1967
31 January 1968
11 March 1968
20 March 1968
11 April 1968
9 May 1968
Entrance dredged 2 3 May - 8 June 1968
Sounding series
31 July 1968
4 September 1968
9 October 1968
28 November 1968
18 December 1968
16 January 1969
18
IV. ANALYSIS OF THE FILLING
The time-space changes in shoaling of the harbor entrance
were determined through analysis of sand volume changes,
migration and change in depth of the channel axis, and move-
ment of selected contours from one survey to the next over
the four-year period.
In order to evaluate the change in volume of the sand
fill between surveys, a computer program was designed. For
this purpose the area of the inlet covered by the Ventura
Port District soundings was fitted with a grid of unit mesh
100 feet by 50 feet, as depicted in Figure 4. The volume
change between successive surveys for each unit area was
obtained in the following way; the differences in the four
soundings at the corners of the unit were calculated between
surveys, these differences were averaged, and were multiplied
by the area of the unit to yield the volume difference. The
summation of all the units gave the volume difference for
the whole inlet between the two surveys, whereas the addition
of the units in transverse or longitudinal sections repre-
sented the respective sectional volume differences between
surveys. It is appropriate to note at this point that
Transverse Sections 1 and 2 are open ended on both extremities,
and that Sections 3 through 7 are open ended opposite the
spending beach.
In some of the figures to be presented, the reader will
note occasional negative values of volume change between
19
,/ATER
TOP OF
LIKE—
JETTY-
o
H
Eh
O
CO
CO
CO
Eh
10
4-4/
\.^
LONGITUDINAL SECTIONS
123^567 89 10 11 lf2
^.^
,"-0,
H?
700
600
500
400
300
200
100
0 100 200 300 400 500^ 600
/
SOUTH JETTY*
0 100
SCALE (i 1 FEET
Figure 4: Ventura Marina Inlet Sounding Grid
and Sections
20
surveys of generally small magnitude. These are believed to
be due principally to the precision of the soundings and not
to the removal of sand. A precision in the soundings of
i 0.3 feet represents a precision on the order of ± 56 cubic
yards for a unit area and ± 6,700 cubic yards for the whole
inlet . The fact that the area studied is open ended
opposite the spending beach may account for some of the
negative volume changes, presumably due to some sand exchange
between the inlet and the beach.
A. SEASONAL DEPENDENCY
A marked seasonal pattern was found to occur for the
sand fill in the whole inlet. This pattern is apparent in
Figure 5, which is a graph of the sand volume changes for
the inlet between successive surveys during the four years
encompassed by this study. Aside from the small apparent
volume losses attributed principally to precision, it is
clear that after the dredging in late spring, the sand
accumulates at a very slow rate during the summer. The rate
increases rapidly between September and November, attains a
maximum value between about November and March, and then
abruptly decreases. The greatest rate of accumulation
between surveys was 8,000 cubic yards in August-September
1966.
This seasonal pattern is further illustrated in Figure 6
which shows the cumulative sand volume changes for the
inlet between successive surveys during the four years.
21
—
1
m
III
CX)
VQ
rH
C--
r-\
<o
o\
m
C7N
rH
1
in
IH
i)0
Ml!
in
. it
i -
in
1
-P
CD
|
j
i
r
1
1
a
x:
.p
;
i
i
u
o
i
Cm
CO
1
i
1
1
1
1
i
1
1
1
i
1
i
i
IK
lit
III
III
l;M
Ml
HI
CD
>
3
CD
>
•H
CO
a
r
j
\t
CO
i i
CD
!
O
O
1
i
1
l
c
!
i
i
i • ■
101
)S1
,n
IH
III
CD
CD
i
i
I
r>
D
1
-P
CD
CQ
rL
I
CO bO
CD C
!
r
hO-H
i
a
i
i
C &0
1 : 1
cti 13
.G CD
r
.
O M
1
I
i
T3
1
1
CD
6 CO
3 CD
1
!
i
|
■
lit
111
m
!-•
m
i
rH -P
O O
> c
[
r
Sand
(D de
i
■
# ,
i
Q
m
CD
M
faO
i
ID
•H
ITS
O
rH
+
c
c
-
3
u
*i
c
u
-f
Li
-J
+
> c
c
D 11
H
"> c
H
)
1-
"N O U
-{ on -
^ c
i L
) t
n c
— c
I
3 U
n c
1 r
H
c
r
r
:> Lj
U 0
H i-
1
H
1
C
Li
3 L
H r
D
H
1
(*sp^ 'no oi) sS^BUO sumiOA
22
in
Ml
ill
ull
L
r!
i
a
1
!
1
i
|
1 :
J
-
Hi
j
1
1
1
o
I
j
' 1
1
1
i I
1
;
] !
?
i
i
i
1
v-
Ml
!t«
■ ■I
i
i
I
1
1
I
i
j
|
i \
1
1
i
[
a
1
_l
1
1
i
1
1
III
in
sn
im
i«»f
ii'
ii •
i'
j l_
\
n
■(i
1
1
1
L_J
in
o
VD
+
LO.
O
en
+
LD.
rH
+
O
in
o
in
o
LTv
O
in
o
in
O
in
rH
1
en
1
VD
1
t>-
1
ON
o
I
CM
rH
1
on
rH
1
in
rH
1
VD
rH
1
-P
ttJ
rH
C
M
0)
£
-P
b
O
<H
CO
CO
VD
>>
CT\
CD
rH
>
fn
3
CO
CD
>
•H
CO
co
(D
O
O
3
CO
VO
C
CD
o>,
CD
rH
£
•P
CD
CO
co
<D
h0
C
cd
£
o
CD
6
3^
VD
rH b0
VD
o c
ON
rH
> -H
bO
T3 T3S
C CD
Cti ?H
CO T3
CD CO
> CD
•H P
-P o
crj C
rH 0)
3 T3
S
3 Q
O^
LO
VD
ON
, .
rH
VD
CD
t*
3
bO
fc
(•spA "no _oi) aSueqo aumioA
23
During the one-year period between dredgings, or dredging
year, the inlet experiences little or no shoaling during
the summer months, then a rapid shoaling during the fall
and early winter, and a decreased shoaling during later
winter and spring.
The volume changes of Figure 5 were prorated according
to the length of the time interval between surveys, and the
average daily rates of fill thus encountered are graphed
in Figure 7. The seasonal pattern of filling described
above is evident in this graph, but it is apparent that the
prorated daily fill rates are more variable . This variability
probably reflects the occurrence and intensity of individual
ocean storms occurring between surveys. The maximum fill
rate observed was about 3,500 cubic yards per day (11 to 20
March 1968) . This figure is equivalent to a daily shoaling
of 0.15 ft throughout the whole inlet for that period.
From Figure 7, the histograms of Figures 8 and 9 were
derived. Figure 8 is a histogram of average daily fill
rates for the whole inlet during the four years . The same
information is shown in Figure 9 in cumulative form. On the
gain side, this figure shows that in half of the surveys the
daily rate of filling exceeds about 800 cubic yards.
The computed annual rates of sand accumulation in the
inlet, extracted from Figure 6, are presented in Table II.
2k
1
j
-j
i
Q
i
i
i
.
! ■
r
i
1
i
"
r1
1
1
i
j
i
i
1
-
! i 1
i
r
I
i
! I
i i
•— — .
1
I
1 1
i
i
i
\d
1
I
i
•
1
i
|o
1
1
!
I
.
i
t
1
i
I
•
1
"1 j
i
a
■
i
1 1
;i
1
-P
CD
rH
CO
c
CT\
1— 1
r-i
CD
£
-P
U
O
U-t
co
>>
CD
>
Ph
3
CO
H
C
CD
CD
5
+5
CD
CQ
CO
CD
bD
C
cti
vo
.c^
U3
O hO
CT\
C
rH
a; -h
E hC
P ID
rH CD
O fn
> TJ
T3 co
C CD
Ctf -P
CO O
C
>s 0)
rH T}
ir\
•H
KO
cd O
i
Q^-
on
+
c\j
+
CM
I
on
I
I
I
t—
CD
hD
•H
Ph
(i^p/-sp^-no oi) 9^H TIM
25
o
c
<v
o
o
o
Cm
O
>s
CJ
C
0)
o1
CD
D
-6000 -4000 -2000 0 +2000
Daily Fill Rate (cu. yds. /day)
+4000
Figure 8: Histogram of Daily Sand Volume Change
Between Surveys for the Inlet
(D denotes dredging)
26
-6000
-4000 -2000 0 +2000
Daily Fill Rates (cu. yds ./day)
+4000
Figure 9: Cumulative Distribution of Daily Sand
Volume Change for the Inlet
27
TABLE II
TOTAL SAND FILL FOR THE INLET PER DREDGING YEAR
(volumes in cubic yards)
1965-66 1966-67 1967-68 1968-69 Average
96,000 115,000 170,000 167,000 137,000
The total sand fill during the four years was 548,000 cubic
yards giving an annual average of 137,000 cubic yards. The
volume differences between dredging years are attributed to
sand supply and transport differences from one year to
another.
Table III presents the dredged volumes of sand according
to the volumetric computations and to the contractor
(Shellmaker Company) estimates.
TABLE III
DREDGED VOLUMES
(in cubic yards)
1965 1966 1967 1968 Average
Computed 122,000 112,000 132,000 154,000 130,000
Shellmaker 146,000 97,450 114,025 135,720 123,300
These figures show a reasonable agreement between the two
estimates. The average dredged volume of 130,000 cubic
yards is of the same order of magnitude as the above quoted
28
average annual sand fill of 137,000 cubic yards, as should
be expected. It should be noted that the dredged area
extended a short distance seaward of the gridded area
shown in Figure 4.
It is interesting to note in Table II the increasing
trend of the yearly amounts of sand fill between 1965 and
1969. It may be also observed in Table III that the volumes
dredged increased in proportion to the previous year's fill.
B. SPATIAL DEPENDENCY
Having established a definite seasonal pattern of filling
for the inlet, inquiry was then made as to where and how the
sand fills the inlet, i.e., what was the pattern of accumu-
lation of the sediment within the inlet and in what manner
did the filling take place.
1 . Volume Changes
The computer was programmed to evaluate the volume
changes between surveys in selected transverse and longi-
tudinal volumetric sections of the inlet, providing an
east-west and a north-south component of the rate of fill.
The sections are designated in Figure h.
a. Transverse Sections
Figure 10 is a graph of the sand volume changes
between successive surveys for the transverse sections 1,
3, 5 j and 8. These sections are presented because they
best illustrate the manner of progressive filling from the
29
entrance of the inlet inward. It should be emphasized
that the three outer sections are open-ended in at least
one extremity.
Other than the seasonal pattern present in
every section, as was expected, another feature is apparent
when the four sections are compared. The range of volume
change is smaller in Section 8, the innermost, than in the
other sections. Significantly, the dredged volumes in
Section 8 are also smaller, thus indicating less need to
remove sand in order to get down to the intended dredging
depth. This indicates that the sand does not penetrate in
great quantities to the innermost reaches of the inlet in
one year. It is also noticeable in Figure 10 that the
volume changes between surveys in the four sections are
generally in-phase . This reveals that the penetration and
deposition of the sand takes place along the whole length
of the inlet at the same time, although in different quan-
tities. These findings are also illustrated in Figures 11
through 14 which show the cumulative sand volume changes
for these sections during the four years.
The annual rates of sand fill in each of the
ten transverse sections is presented in Table IV. The
figures show that the greatest accumulation rate occurred
in Sections 4 and 5 just inside the seaward end of North
Jetty in three of the four dredging years. Thus it appears
that the sand accumulates mostly in the outer half of the
inlet .
30
CO
C
O
•H
cr>
-p
vo
o
CT\
CD
r-\
CO
CD
CO
Fh
0)
>
co
C
cd
F-i
Eh
co
cr\
<D
<-\
>
fn
3
CO
CD
>
•H
CO
CO
CD
CJ
O
3
co
vo
C
\o
cu
cr\
CD •— v
i-^
5 hD
-P C
0) -H
PQ tu)
73
co d;
CD £n
hOT3
C
cti co
x: (U
O -P
o
CD C
£ CD
3 T3
in
i-H
KO
O Q
ON
> —
o
CD
U
bO
(•spA -no pOI) sSublio amniOA
31
HI
111
>lf
—
-
—
4-i-i-
— T
— -
r
—
H
111
■ •
110
un
im
iinr
irnir
HI
Ml
II"
111
" " " ""
I
-
.
—
r
_ r
• i •
1
J
^
—
•
110
'OH
10
HIS
HI
unr
III
III
II"
111
«ir
—
—
—
Q
■
r
!>
1
1
i
. . ri
4. . .
ill
■on
no
in
jiii
unr
i»nr
na
in
in
III
,nr
J
r_
—
—
r1
i
h\
6
1
r1
—
....
....
•
—
j-;
no
i»
in
III!
m
unr
unr
in
Ml
III
III
III
c
d[
....
. . ,
o
iH
+
LT\
I
\S\
O LT\
C\J OJ
I I
oo
c
O
•H
-P
O
CD
CO
r—
VD
CD
a\
to
rH
u
CD
>
CO
C
cti
Pn
|
w
CD
hO
C
cti
x:^
\o
O hO
VX3
C
CT\
CD «H
H
6 M
3 'C
rH CD
O £-.
> T3
CD TJ
> CD
•H 4->
■P O
ctf C
iH CD
3 TJ
e
3 Q
o ^
LT\
U3
cn
• •
rH
iH
iH
CD
^
3
hO
o
en
i
Ph
(•spA *no pOI) sSLreUO aumioA
32
. .
m
in
m
X)
l-H
r
L
"1
■ -
M
•.■
im
»i
iar
Mi
w
!!■
Ill
h
D
i
i
1
m
ii
i
C
L
o
1
'«»
•H
i
. J
>]J
-P
i
r
I
,
O
i
11 IS
■ »
CD
CO
i
i
■■
fr-
CD
f
i
\o
CO
.
I
i
a\
.,.
0\
H
CD
>
r
i
Ml
CO
L
i
i
i
i
i
■ ••
cd
i
■
U
1
».
Eh
~L
i i
I
i
1
in
1
i
CO
i
i
-
I
<D
i
1
faO
I
r—
— i
c
i
s
"i
cd
L
vo
O hO
i
„•
c
I
i
i
CD iH
i
.:«
iH
e bo
Ql
3 T3
i— 1 CD
i
O fc
j
i
I
i
1'.
> T3
CD CO
Ml
> CD
t
•H -p
P O
i
•
cd C
.— 1 CD
I 1
1
1
3 T3
3 Q
l«l
CJ> v-^
l
rir
m
i
:
$m
• •
i-H
C\J
Q
w
i-H
141
CD
n«
Fh
i
III
3
bO
•H
1 1
.•■
ft
o
iH
+
+
LOi
m
o
CM
I
C\J
I
o
m
I
(•spA*no oi) sSubuj suiniOA
33
... | ...
... I .
in
in
i
r
iir
;;;;:
- . (
i
1
i • •
in
Hi
m
UK
L
. ....
■ • ■
L
.inr
d
>
i
^r
I Mir
in
m
. . .
in
.ii
J
r
in
1
i
•
•
i
|
i
!
i
i .
i
'Ok
131
l
Mi
T
i
n
mor
_J '
i
HI
1 .
IK
1- •
i
■ T
i
an
1 ,
...
i
i
i
i
*
r
-
l:; I
. ...
•
i
i
ol
iNfir
H
IK
•
I
111
i
111
in
no
1
I
n
.IIS
in
!
o
1
«nr
IIR
Ml
■ •■
III
-j
i
LO
O
r\j i— i
+ +
o
rH
+
O
ir\
l
o
iH
I
rH
I
o
c\j
I
CO
VD
CTv
CX\
ON
iH
C
O
•H
■P
O
CD
CO
CD
W
fn
CD
>
CO
£
cti
Eh
CO
CD
G
«5
O h£)
c
CD iH
6 hD
H CD
O Ih
> T3
CD
>
•H
-P
cd
e
o
w
-p
o
i:
Q
CO
CD
hO
•H
Ph
(•spyC'no j-OI) aSu^qo eumiOA
3*
—
111
III
CO
V£>
0>
rH
f-
rH
VO
cr\
H
in
VD
ON
H
r
r
lit
III
l»
lilt
111
III
III
III
L
D
i
i
i
|
1,
CO
C
i
L.
J
i
!
III
IN.
IN
.Hi
in
IMI
hi
Hi
in
In
mi
o
•H
•P
a
CD
CO
(D
CO
r
Q
!
1
1
i
i
CD
>
CO
a
M
Eh
1
1
in
in
in
lit
in
lllf
linf
ill
III
III
III
HI
CO
J
j
I
le Change
ing)
f
J
i
!
3 T5
Q
i — 1 (I)
O Jh
> T3
CD CO
> CD
•H P
P O
^
3
N.
i
ill
III
IM
lilt
Ml
iiir
liir
ill
Ml
III
HI
ii'
cd C
1 : Cumul
(D de
Q
1
....
■ ■ 1 ■
CD
ti
Z3
hO
•H
-1
Ph
H
1-
C
r
-
H
r-
H
■>
c
)
LI
r\
c
r
D
H
1
L
r
H
1
o
C\J
1
(•sp^'no pOI) 93u^qo aumiOA
35
b. Longitudinal Sections
The longitudinal sections selected to illustrate
the manner of filling across the channel were numbers 2,
5, 8, and 11 (see Figure 4). The cumulative sand volume
changes for these sections during the four years are shown
in Figures 15 through 18.
The seasonal pattern is again very clearly
present in Sections 2, 5, and 8. Section 11, however,
differs in this respect; indeed, it seems to have a random
distribution of sand volume changes. It is also apparent
that this section, the southernmost of the four, experiences
much smaller sand volume changes than the others. This
section clearly lies outside the dredged channel since the
effects of dredging are inconspicuous.
The volume changes between surveys in Sections
2, 5, and 8 are generally in-phase, meaning that deposition
of sand occurs across most of the width of the inlet at
the same time. Section 11 clearly behaves independently.
A comparison of the sand fill rates in each of
the 12 longitudinal sections is presented in Table V.
These results show that Sections 3 and 4 have the highest
average rates of fill. This indicates that filling occurs
most rapidly near the North Jetty.
It should be kept in mind that the volume com-
putation for each longitudinal section, as for each trans-
verse section as well, is an integration over the whole
length of the section. Nevertheless, it may be concluded
36
M
ttrr
i i ■ .|
-+ t-t -
• * — -
—
....
! !
^.i.
— L_
....
•
in
■
1 1 1 !
-U-U
....
-. * . .
1
Rj-
....
....
1
ii
m
. . . .
• - t- *
—
m
III!
T • T-
an
1
m
•'•
. : . .
1
>
Iff
-1-i-H
i.
1
1
.
III
in
"
i
J
,....
::l
m
im
!•!
L
r
Jo
in
HI
!*■
l<<
^J
1
j
II
—
H-r-
r1
(.....
IM
III
Ml
IV
■-■ ■
c
'
. .
141
ii a
II'
i
J
....
—
1
3:
L
IM
.ill
in
.'»
I4i.i
....
....
1
Ml
• ii
Ml
ni
in
....
....
.1..
"1
IT*
oo
+
co
ON
ON
vo
ON
ON
^3-
co
CNJ
vo
•o
-=r
CO
1
l
H
1
1
CNJ
1
CM
I
CNJ
1
(•spA -no oi) ^Suei\o aunioA
37
m
in
■ir
1
1
I
lit
HI
ill
Mil
III
nif
ill
in
in
...
|_
-
1
i
rjl
XI
i
i
o
:
1
1
i
i
H
_l
i
!
i
i
LT\
o
1
1
'01
I'O
U'l
nnr
i:B
141
IIR
III
H
67
al Secti
i
O
CTi c
T3
.
r
3
-p
•H
'!
r1
hO
c
o
1
■ ■"
1
1
i
:ig
M
in
IIR
111
1
i
1
i
to
faD
c
i
i
i
19
e Volume C
s dredging
Q
•
1 I
,
!
1
:
i
i
|
i
111
IN
ill
HIS
!«!
im
lur
iir
in
in
in
«ir
> <D
1 —
1
•H -P
-P O
«J c
r-i <\)
3 T3
r — '
J
6
in oCi
'
1
«>
19
re 16 :
i
hO
o
^3
-♦
r
c
D
■=3
1
o
0
1
r
p
H
1
r
>
C
C
3
1
o
r
j
a
o
1
J
(•sp/: -no pOI) a3uBLjo auinxoA
38
m
—
in
1
f
m
i ! '
....
4-k J-
r1
lit
■ B
in
....
1
Mi
• it'
i
L
6
• -
jj
•
III
in
. ..
f ■
m
in
■if
1
.
-
i
■•«
l
Kll
d
•
in
....
IV
tit
H
Id
i
S
....
L
in
*— i
=>
■ 1
i
III
....
Hi
.11
....
...
1
< 1
in
.)■
in
Mil
i
a
i
b
r
III
1
• If
I
"T
V
-
III
HI
L
- —
.!•
L,
■ ■ i
urc
?
t'lr
HIT
F
III
M
m
in
L
VD
C\J
oo
+
oo
I
(•spA -no pOI) a9ueqo aunxoA
CM
i-H
I
I
OO
CTn
vo
CTN
o^
oo
c
o
•H
-P
O
(D
CO
C
•H
-P
•H
hO
C
o
w
<D
hO
C
cd
O hO
C
e bo
3 X)
i— I <D
O k
> T3
<L) W
> <D
•H -P
-P
Cti
o
C
rH (U
6
0)
39
... -
.
III
■II
Iff
r
...
■ -
r
r1
hi
u»
IJO
mh
hi
.'■or
IIH
IfR
<«>
III
III
mr
. ■ j
I
—
-—-
I
1
—
—
110
'»»
l][
HIS
mi
itnr
mar
IIN
nt
sift
ill
ivr
-
c...
ja
-i
—
—
....
—
1
in
ion
in
.11!
m
.
IMI
111
u>
IK
III
n
....
1_
1
—
J
1
j
c
1
ri
i
i
■
III
101
111
ms
tit
itnr
Kir
na
141
III
III
T.
....!-. .
....
i
L
.
....
Ql
....
.
....
p
....
....
....
. ..
_
CO
CTN
CM
rH
+
a j
+
I
co
I
LPs
rH
O
•H
-P
O
CD
CO
H
a
r—
c
VD
•H
CT\
T3
H
3
-P
•H
hO
C
O
1
w
CD
hO
C
ctf
.c^
O faO
vo
CD -H
H
e m
3 T3
rH 0)
O U
> -a
0) w
> CD
•H -P
•P O
cti C
rH (D
3 -d
S
3 Q
o
CO
CD
hO
•H
(•spy? "no oi) s3ubuo aumiOA
40
>
H
W
CO
<
Eh
00
O
H
En
O
W
00
w
00
cr;
w
>
oo
<
cr;
E-t
W^
[U CO
CC cd
O >5
o
Cr; -h
< O
w d
->H O
C3 C
H
O CD
s
3
g
Q O
>
cr; ^
W
Pm
H
Ph
Q
<
oo
o
oo
w
Eh
<
cr;
oM
oo
vol
ml
on|
oo
o
o
O
O
o
o
o
O
O
o
o
rH
t--
m
in
oo
VO
t^-
oo
C~-
o
o
O
o
o
o
o
O
o
o
o
r-\
rH
oo
vo
[>-
VO
OO
CTi
C--
o
o
O
O
o
o
o
O
O
o
o
LT\
r-\
OJ
o
t—
t>-
<J\
CM
0>i
o
o
o
o
o
o
o
o
o
o
o
VO
rH
CM
t>-
c—
ON
o
VO
o
o
O
o
O
O
o
o
o
O
O
VO
on
■=}■
o
VO
o
oo
o
oo
LPv
rH
rH
CM
r-^
rH
o
o
o
O
O
o
o
o
O
O
CO
in
o>
OO
LT\
in
oo
o
t^
O
H
rH
oo
rH
CM
o
O
o
O
O
o
O
o
O
O
vo
oo
o
VO
r-\
vo
oo
oo
o
CM
rH
rH
oo
CM
CM
O
O
o
O
O
O
O
o
O
O
rH
VO
o
VO
OO
oo
in
vo
C\J
CT\
rH
r-\
CM
CM
rH
O
O
o
O
O
O
O
o
O
o
o
LO
l>-
VO
t>-
oo
LT\
CT\
VO
oo
<-\
rH
rH
CM
rH
o
O
o
O
O
o
O
o
O
O
CO
C\J
o
LO
in
o\
-=T
CM
VO
LO.
H
rH
CM
rH
VO
tr-
OO
CX\
<v
VO
1
vo
1
VO
1
VO
1
hO
cd
LO
vo
r>-
oo
?H
VO
vo
vo
vo
0)
CT\
cr\
ON
c^
>
rH
rH
rH
rH
<
>
w
CO
<
En
00
s;
o
(H
Eh
O
W
O0
<
M
Q
1=3
Eh
M
O
o
w^
Eh TJ
cr; cd
O >>
o
cr; -h
<C o.
w
o
H
O
Q
S
Q
cr;
w
tH
Q
<
00
o
00
w
Eh
<
cr;
3
o
•H
CD
6
rH
O
>
o
o
o
o
o
cm|
o
o
o
o
o
h|
vo
CM
o
vo
vo
oo
oo
oo
^3-
oo
o
O
o
o
o
rH|
o
o
o
o
o
rH|
rH
oo
^r
o
in
-=3"
oo
^3-
VO
^3"
O
o
o
o
o
°l
o
o
o
o
o
<h|
in
vo
oo
oo
oo
in
VO
-=r
o
rH
vo
o
o
o
o
o
o
o
o
o
o
C*|
oo
o
oo
oo
^3-
vo
a\
o
in
o
t-\
H
r-i
o
o
o
o
o
o
o
o
o
o
oo|
rH
oo
CM
H
t>-
t—
oo
vo
in
H
<-i
H
H
o
o
o
o
o
o
o
o
o
o
t—l
■=r
CM
vo
^r
CM
o\
o
o\
r>-
^r
r-\
H
<-{
rH
o
o
o
o
o
o
o
o
o
o
vol
o
o^
ON
t>-
rH
CM
^r
o
o
r~
H
H
CM
CM
H
O
o
o
o
o
O
o
o
o
o
Ln|
oo
oo
OO
CM
CTi
-=r
rH
oo
^r
o
rH
CM
CM
CM
CM
O
o
o
o
o
O
o
o
o
o
^-1
vo
o
^=r
vo
CM
[—
VO
r^
in
^3-
tH
CM
CM
CM
CM
O
o
o
o
o
o
o
o
o
o
oo|
CjN
CO
o
in
^T
c~-
oo
oo
-=r
oo
r-\
CM
CM
CM
CM
O
o
o
o
o
O
o
o
o
o
CM|
O
oo
-=r
vo
-=r
H
o
ON
vo
^r
H
H
<-{
H
H
O
o
o
o
o
o
o
o
o
o
rH|
■H
oo
CM
vo
oo
oo
CM
vo
in
-=r
VO
[--
oo
ON
<u
VO
1
vo
1
vo
1
vo
1
bO
cd
m
vo
r>-
oo
Ph
vo
vo
vo
vo
a;
o>
a\
ON
cr\
>
rH
rH
r-\
rH
<
Hi
that the area of maximum sand accumulation over one dredging
year lies approximately at the intersection of the trans-
verse and longitudinal sections having the maximum rates
of fill. This places the general area of greatest fill
about 200 feet east of the seaward end of the North Jetty.
2 . Channel Migration and Depth Change
Having determined where in the inlet the highest
rate of shoaling occurred, the attempt was made to under-
stand in more detail how the sand accumulated. To accom-
plish this, the migrations of the channel axis and its depth
changes were examined for the four years. It is appropriate
to note here that a single channel axis was found in nearly
all surveys.
Both the location and depth of the channel axis
and the width of the channel were determined from the bathy-
metric charts shown in the Appendix for four representative
transverse transects. The transects selected are located
at the entrance (0 ft range line), 200 ft range line, 500
ft range line, and 800 ft range line (Figure 4). The data
for these transects are presented in Figures 19 through 22.
The channel width was defined by the horizontal distance
measured in the transverse direction between the pair of
contours having an elevation of one foot above the channel
axis.
An examination of the graphs reveals, first of all,
the seasonal pattern already described, although the pattern
42
-"•""I
|::
:
1
1
■ii
m
>
*s%^-
1
1
<.
„>l
n>
\
^
^
■
»••
t '
III
J^
I
1 <
o
H , g
£^
g ! h
(
!
i
t:
III
> i
i
p
\
i
H
/
■
•=»
i
1
i
i
i
\
i
|
1
i
i
i
^~*'*^
X*
1
i
i
j
;
f i
~~~~"
i
i
|T»
i
1
1
i
i
1
i
•
i
i
,-—-
Q
HI
^^^
1
. \
III!
HI
i«l'
•
ill
Hi
Hi
o o o
i-h c\j on
o
o
o
o
MD
in
(199J)
HLflOS
Lftdaa umuixx^ xauireqo
cv
o
o
o
o
m
o
o
CM
o
o
o
HLUON
OO
OS
On
-P
O
CD
CO
C
a)
F-i
Eh
CD
C
•H
►J
CD
bO
C
«j
K
-P
o
£
-p
Q.
CD
o
T3 ^
C bO
cd C
t-i
•H
C bO
O T3
•H CD
P U
a td
o
o to
J CD
-P
rH O
CD C
C 0)
C T3
cd
x: o
o ^
ir\
vo
CT»
i— i
ON
rH
CD
Ph
3
bD
(^88J) /^q.af Uh^iqn ukwj aouB^sxa lauLTBqo
43
i
in
1 '
'
«if
S^^"^^»^L
110
^v^^
'
10"
^^x
no
V \.
MR
-
a
"•"'
ITU
CO ,
i
H i w
■
X ! 1 Eh
!
■ID
^P
^*"
^^^S^c?*^
^ i n
I
_/ H
V ^^"^ T
1,1
V
« "
i
:f
En
111
Q
H <
[2S
,
1
IT*
\ w
1ft
!
=ss
-7«
— — -
1 1
i
i i
i
i
I 1
,n
.
~~a
^-
'
w
1
T" — »^i
i
111
\
\
111
\
in*
s\
i j
nit
i ^__^
Q
"~<^ —
1
HI
p***^
li»
Hi
o
CM
o
m
o
o
o
o
in
o
o
o
o
o
o
o
o
oo
VD
in
0>t
o
KLHON
(isaj) j^3f M^ion uioaj soue^s-fa xauuBqo
MH
I
i.<
! II
in
1
/
"'
v
r
1
: H
•*"H~r"
.. . . .
Y
■
....
NH
v
.
X
N
- ■ •
| '
UR
—
\
, —
)H
m -r-
****
j
\ Q
J \
1
!
III
Uf
^^m ■«
'
1
II*
i
III
.
'!»
CO
H
/ /!/
••I
In
- . _«_
—
3
\ i
O
y
i
3 I
in
1
Eh
Q
H
i ■
m
~3 /
>
.
•ii
■ - ■
....
.
:t
■ — - -
. . *. .
j^p^
m
. ■
-
in
"**s,»««>j
C
. 1
in
i
|
I
ii"
c
in
hf
.....
—
j ■
.11
• : r
L
^
•
. . j ...
i !
m
\
■■/
/
^
Q
--- j
....
«!■
\
.
■
in
P
" ""
....
o o o
<-i c\j on
o
o
o
o
VD
m
(^SJ)
KLQOS
qq.d9Q umurireiAi lauLreqo
0
o
o
o
o
en
o
o
o
o
KLHON
co
vo
o>
CT\
in
VD
o>
&H
(^aaj) /ft^f q^iOM uicvij aoire^siQ lauireqo
45
o
o
o o
m o
o
o
in
o
o
o
o
m
o
o
o
o
Rinos
HIHON
(:*aaj) £3W q^JON moaj soLre^Sfa IsuuBqo
H6
is subdued in the innermost part of the inlet . It is apparent
in both the channel migration and channel axis depth.
The channel axis migration is the most revealing
feature of these graphs. In each transect, particularly
the outermost ones, it can be seen how, after the yearly
dredging which placed the channel axis close to the North
Jetty, the channel moved southward, very slowly at first
during the summer, then very rapidly in the fall, attaining
its southernmost position in the winter or spring before
the next dredging. This clearly indicates that the entrance
channel is being filled along the north side, particularly
at its seaward end. The magnitude of the seasonal movement
of the channel in these four transects for the four years
is summarized in Table VI.
The width of the channel, represented in Figures 19
through 22 by the envelope around the channel axis, does
not seem to yield much information. It was expected that
the channel would be widest immediately after dredging and
that it might become increasingly narrow as it filled;
however, no pattern could be delineated from the graphs.
With regard to the depth of the channel axis, the
graphs show that the seasonal changes of the channel axis
depth are smallest in the innermost 800 ft transect. This
is consistent with what was found in the study of the trans-
verse volume sections; namely, that less sand accumulates
in the innermost regions of the inlet. Table VII also
demonstrates this observation.
^7
TABLE VI
SOUTHWARD MIGRATION OF THE CHANNEL AXIS
IN EACH DREDGING YEAR FOR RANGE LINES
0 FT, 200 FT, 500 FT, 800 FT
(in feet)
0 200 500 800
1965-66
280
250
75
100
1966-67
350
400
200
150
1967-68
325
475
350
125
1968-69
100
300
50
75
Average
264
356
169
113
TABLE VII
DECREASE IN CHANNEL AXIS DEPTH IN EACH
DREDGING YEAR FOR RANGE LINES 0 FT,
200 FT, 500 FT, 800 FT
(in feet)
200 500 800
1965-66
12
9
5
7
1966-67
12
14
8
2
1967-68
6
15
26
7
1968-69
18
16
12
7
Average 12 14 13
48
It is noticeable in Tables VI and VII that the
southward migration of the channel axis and the amount of
shoaling of the channel had maximum values in the 200 ft
transect. This is not surprising, since this transect
crossed the general area of maximum sand accretion.
3 . Contour Migration
It was felt that a study of the movement of the
bottom contours between successive surveys would be helpful
in the understanding of the configuration which the sand
body assumed as it deposited. That is, did the sediment
accumulate as a progressing sand fill and if so, did it
migrate across or along the inlet; or did it tend to fill
the deepest areas first, producing a flat bottom as it piled
up? In the first case, the sand would progress as a steep
"front", keeping its advancing slope relatively constant.
In the second case, the sand would present gentler slopes
and would shoal the channel axis more heavily.
It is readily apparent from the series of sounding
charts contained in the Appendix that the inner half of
the inlet fits the first model and the outer half follows
the second. To illustrate this fact Figure 23 was prepared
to show a time series of the -20 ft contour utilizing
selected surveys between the dredgings of 1967 and 1968.
It clearly shows how the sand mass encroaches rapidly across
the inlet from the north end of the North Jetty. It may
also be seen that the sand moves into the inlet along the
^9
JETTY
1CA1I
Figure 23:
Position of the -20 ft Contour
From Surveys in 1967-68
A - 2 June 1967
B - 17 October 1967
C - 31 January 1968
D - 11 March 1968
E - 20 March 1968
F - 11 April 1968
50
North Jetty, progressing very little into the inner half
of the inlet. The survey charts for 31 January and 20 March
1968 (see Appendix) show particularly well the gentle slopes
of the fill in the exposed harbor entrance and the steep
slopes in the quieter water inside the inlet.
These concepts were further examined through analy-
sis of the migration of selected bottom contours along
transects taken at the 200 ft and 500 ft range lines. The
contours chosen were 10 ft, 16 ft, and 20 ft; they were
selected for their representativeness and because they
were also present most of the time in the transects.
Figures 24 and 25 show the graphs thus constructed.
Figure 25 reveals that in the 500 ft transect the
contours adjacent to the North Jetty stay packed together
as they advance with a high slope across the inlet after a
dredging. The same contours on the south side indicate a
much gentler slope and don't migrate. The year 1968 seems
to have been exceptional in that the 20 ft contour moved
completely across the inlet whereas in the previous years
it went only as far as the mid-point of the inlet. Examining
Figures 25 and 21 jointly, the seasonal history of the sand
movement across the transect becomes even clearer. It can
be seen that dredging produces a steep slope along the north
side of the inlet. The sand "front" progresses from the
north and shoals the channel as it pushes the axis toward
the south.
51
Similar conclusions can be drawn for the inner
transects since the behavior of the contours on the sounding
charts is very similar to that on the 500 ft transect, with
the exception that the rate of contour migration is less.
Figure 2k depicts the migration of the contours in
the 200 ft transect. It is readily apparent how different
this graph is from Figure 25. The contours on both sides
of the inlet, after being separated through deepening of
the channel by dredging, remain separated through the summer
months until they join in the fall due to sand accumulation.
At this time of the year the slope of the southward encroach-
ing sand body is fairly gentle. The sand doesn't creep
along as a slip face; instead it tends to settle on the
bottom with a gentle slope . On the south side of the inlet
there is no evidence of sand deposition, the contour movement
possibly responding to variations in the waves passing through
the entrance to the spending beach. As in the previous case,
the joint examination of Figures 24 and 20 for the 200 ft
transect will provide a more complete picture.
52
-p
•+-j
<tH
r
i
**T-
vO
»*.^
-fs
. . .
H
«« .
rA
**•+■ -'
* - •■ t—\ —
- 1 — >■
'
■
/
■
:
_ ^r
■ • - *
> . . .
w
<
1 ► »
. . .>
. - . .
\
■ ■ i
i
V-~
— •—f ■ """"
•4" " !
U
a
.»<
.*> —
*
!
i
• ■
<
i
....
c.
i
— —
■-'._
III
•
^^s^
h«v
• <
^
">w 1
V
1
'1
\
/S
■ •
-P
'>
k
//
a;
I
1
i^V
1 N
•
m
1
)
\
1
C
■
|
•
cd
1
j
|
i • -
r-
Fh
<0
Eh
I
1
1 '
1
iH
<D
1
,
H
/
1
-•— .
-.—.<
i - -
..i
■
c
•H
bO
C
"^ .
■ v
cd
s*
X
*Z
i
1
. i
••
-p
Q-l
>s
* l !
.
.•*••"
/
'
f
o
^
i r
■ •
<o
o
CM
i V
■
<o
1 '~N
\
CT\
L^
•>
^f*
1 V
<H
J.. -
, J 1
!fi
■ — ■
•._,,.
-s;
1
<"
.-•
3 bO
O T3
1
<L
1
\
•
-
-P CD
C *H
i
"~*"~fc — •-.
"-.
*
O TD
O
'V
i
/
i
CO
x
i
S. I .'
, i
T3 CD
r
N i
/
>••
CD -P
V
V *
S
-
-P O
/
T\ N
X
in
O C
CD CD
/
>
VI
\
I
1
'•'
LT\
r-i T3
CD
,.*
1
Wl
ON
iH
i
«*»■
- 1
II
(^
__,_.
— • —
— •— '
i - ■
^3-
C\J
....
+3 .T5
.. .
«<
-•-,
...J -p
y
y
n
CD
.>vO.
«
*;^
£>
— —
/
3
i-H
H
bO
•H
nine
)C o o
8 S 8 S HLHON
u
3
Lf
\
^
r
o
n
c\
I
P"
i
(Q.99J) Aq.q.af q^JOM uioaj aoueq-Sfa dnoq.uoo
53
4»-
^ .
O
p
in
in
■ir
P
....
....
s>
/
V^J —
i-H
1 (
CN
V
V
101
—
—
i J
s»
i
i
—
in
h
III!
)•!
nor
nor
//
J
-.-"
~*
L-""
o
< i :
.
tTR
. . .
*Qgg
■°*
... i
—
III
M
\
1 **
—
III
A
i
i
^
mr
•^ y
i
VI
111
K
....
Nj
\
DO
--»•
.
.
I1,
__ i "
lilt
,^^
i
\
-
\
"'
i
i-
!i
in
Hflf
\
■ I I
Jj I
/■N
ITU
■*-, L-^
_^*
M
/ \
5o
J
III
i \
^s^n
/ i
... .
}....
111
III
i \
Vv''
! ■ ■
1 •■
1 \ v
I
S
J J
....
^
i
110
1 s
\ .
i
•
s
\ j\
\\
\
...
i /
[(
%
i
HIS
.*' ' C
i
r
i
101
.•
\
V
f
nor
mot
fc^
I
\
F*
■ l*<*
wgl*?^'
"b;
in
^^^
• »,
««•
— — —
'*** T\
^L>
IK
V
f
..
III
v /
AW
mr
N i I
V
:io
/ J
y>
'01
\ J
//
1)0
i S
Vi
i
HIS
/ \
t
^^
<U
i«i
'
f
ft
nor
^
\i
t ■
1
X
^*^
f
in
p
\
p
^^^
Q
f-H
*
in
HI/10S Q
o
VD
O
O
in
o
o
o
o
en
o
o
C\J
o
o
HLHON
CO
i— i
p
o
CD
w
C
ctf
U
E*
r—
md
(1)
o\
c
i-\
•H
iJ
<1)
bD
C
cd
K
-p
Cm
O
O
LPs
KO
1 hO
\r>
C
C7\
CO tH
r-\
Jh bO
^S T3
O CD
■P tH
C T3
o
o w
CD
TS p
CD O
P C
O CU
CD TD
iH
CD Q
CX) ^-'
LT\
vo
rrs
* *
i— i
LT»
C\J
CD
M
S
hO
fe
(^aaj) /J^^af q^ioN uioaj aouB^sfa «mo^uoo
5^
V. INTERPRETATION
The final questions that were considered had to do with
the source of the sand shoaling the entrance, the mechanism
of sand supply, and the reason for the patterns of sediment
accumulation observed.
A. THE SAND SUPPLY
The fact that the greatest fill rates occur on the in-
side of the North Jetty at a location some 200 ft from its
seaward end in the shelter provided from the dominant west-
erly waves (note Figure 4) points to downcoast littoral
drift as the principal source, if not the only source, of
the sediment which shoals the Ventura Harbor inlet.
Upcoast drift on this coast is presumed to occur in the
summer associated with Southerly Swell (Oceanographic Ser-
vices, Inc., (Phase II), 1965); however, there is no evi-
dence of any accumulation in the lee of the South Jetty
or anywhere else in the inlet in that season. It may be
concluded that these waves are ineffective, partly because
of their low frequency of occurrence, in shoaling the har-
bor. In view of the latter consideration it is interesting
to notice that about one half mile downcoast the Santa
Clara River contributes on the average an estimated 600,000
cubic yards per year to the littoral sand supply (Department
of Water Resources, 1969) •
55
It was pointed out that the estimated net annual lit-
toral drift rate downcoast in this area is 400,000 cubic
yards. The average annual deposition in the inlet is
137,000 cubic yards, which represents about one third of
that amount .
B. DYNAMIC EQUILIBRIUM CONSIDERATIONS
The dynamic equilibrium condition of the inlet involves
the concept of tidal prism and equilibrium throat area.
The tidal prism of a body of water in connection with the
ocean is given by the volume of water that passes through
the inlet on flood or ebb tides. It is equal to the product
of the area of the water body by the tide range. O'Brien
(1931) developed a relationship between the tidal prism
and the throat area of an inlet, or minimum cross-sectional
area of the inlet below Mean Sea Level, when the inlet is
in equilibrium with its hydraulic environment, i.e., when
the scouring action of the tidal currents keep the throat
area constant over a period of time.
In this thesis O'Brien's relationship is applied to
the entrance of the Ventura Harbor inlet, and the following
results are obtained:
j- = 2.h x 103 P0'15 (ft) (O'Brien, 193D
P = ah (cu ft)
56
where
a = 7^0 x 10 sq ft, area of harbor
h = 5.4 ft, diurnal tide range (MHHW-MLLW)
A = 1,200 sq ft, equilibrium throat area (below MSL)
The throat area of the entrance below Mean Sea Level
was considered for the most shoaled condition encountered
during the four years, namely at the peak of the shoaling
season in 1968 (survey of December 18) ; the value was 9857
sq ft below MSL. A comparison of this figure with the
theoretical equilibrium value of 1,200 sq ft proves to be
on the order of 8 times larger. This means that the Ventura
Harbor inlet, even when filled with a year of sand accumu-
lation, had not reached dynamic equilibrium and that the
entrance might be expected over a period of years in the
absence of dredging to become considerably shallower.
C. THE MECHANISM
Two agents can be responsible for the shoaling process
at Ventura Marina, namely tidal currents and waves.
The fact that the cross-sectional entrance area is well
in excess of the hydraulic equilibrium area implies that
tidal current velocities in the inlet are weak. An estimate
of the maximum tidal current through the entrance was made
for several ranges of the tide. The volume of water passing
57
through the entrance was equated to the tidal prism of the
harbor for a one-hour period around the time of maximum
water-level change. The tidal curve was considered to be
a sine wave of semi-diurnal period 12.4 hours. The maximum
water level change in one hour is 1/k the tide range. The
results were as follows:
v = TT (ft/hr)
where
h
a = 7^0 x 10 sq ft, area of harbor
A = 9857 sq ft, throat area of entrance
below MSL at maximum shoaling
h = tide range
v = tidal current velocity
For h = 10 ft, the largest observed tide range, v = 0.52
ft/sec;
for h = 5.4 ft, diurnal tide range, v = 0.28 ft/sec; and
for h = 3.7 ft, mean tide range, v = 0.19 ft/sec.
These values of tidal current velocity under the most
extreme shoaling condition observed were entered on a sedi-
ment transport graph for steady unidirectional flow (Coastal
Engineering Research Center, 1966, page 155) to see whether
tidal currents alone should be expected to move sand. All
velocities proved to be non-eroding, with the exception of
58
the extreme tide condition. Indeed, at a velocity of 0.52
ft/sec a steady current just begins to move sand of particle
diameters between 0.18 and 0.7 mm. The sand in the inlet
has an average median grain diameter of about 0.2 mm
(Oceanographic Services, Inc., (Phase II), 1965). It must
be noted that the extreme tide range was observed only once
at adjacent tide stations (National Ocean Survey, 1962 and
1968), and is certainly a unique situation.
Thus, waves remain as the main cause for the shoaling.
Independent evidence to support this conclusion is provided
by the correlation between the seasonal volume shoaling
of the inlet shown in Figure 5 and the seasonal wave regime
presented in Figures 26 and 27. The latter diagrams, prepared
by Dr. Warren C. Thompson from North Hemisphere wave-hindcast
data compiled by National Marine Consultants (i960) at
their Station 5, show the frequency of occurrence and rela-
tvie wave power for waves entering the westerly and southerly
wave windows shown in Figure 3- The agreement between the
annual patterns shown in Figure 5 and Figures 26 and 27 is
clear. Southerly Swell due to Southern Hemisphere storms,
which has its highest frequency of occurrence in the Northern
Hemisphere summer months, is not included in the data; its
energy is very small relative to that represented in Figure
27.
As a result of these considerations it appears that the
larger westerly waves arriving from the open ocean, with
59
Figure 26: Frequency of Wave Occurrence
(from W.C. Thompson)
60
30000
25000
WEST AND
SOUTH WAVES
o
I
CM
III
P-,
20000
15000
I
P-.
jg 10000
B
•H
5000
Figure 27:
J
Relative Wave Power
(from W.C. Thompson)
A
0
:;
r
61
their energy concentrated by convergence, cause sufficient
turbulence at the entrance to the Ventura Marina inlet to
maintain in suspension the sand supplied by littoral trans-
port. This suspended sediment is subsequently carried into
the mouth of the inlet by the same wave action, undoubtedly
reinforced by the flood tides. Much of this sand fills the
seaward edge of the dredged channel. However, a substantial
amount, due to refraction of the penetrating waves around
the North Jetty, comes to rest just inside the sheltered
lee of the jetty, as witnessed by the higher fill rates in
that area (Tables IV and V). At the same time, as the re-
fracted waves travel around the end of the North Jetty and
up the inlet they transport sediment as littoral drift
depositing it along the north shore of the inlet.
The slopes assumed by the deposited sand also appear
to be controlled by the amount of turbulence and wave activi-
ty. The inlet is exposed to westerly waves which penetrate
along a corridor leading to the spending beach where their
energy is effectively dissipated. In this area of maximum
wave turbulence the sand fill presents gentle slopes. In
the sheltered region of the inlet behind the North Jetty,
however, the slope of the advancing sand fill is steep and
appears to represent a slip slope at the angle of repose.
These different slopes seem to be related to the effective-
ness of the waves in stirring the deeper parts of the
channel .
62
LIST OF REFERENCES
1. Coastal Engineering Research Center, Corps of Engineers,
U.S. Army, 1966. Shore Protection, Planning and Design.
Technical Report No. 4.
2. Corps of Engineers, U.S. Army, Los Angeles District,
1970. General Design for Ventura Marina, Ventura
County, California. Design Memorandum No. 1.
3. Department of Water Resources, State of California,
1969. Interim Report on Study of Beach Nourishment
Along the Southern California Coastline.
4. National Marine Consultants, i960. Wave Statistics for
Seven Deep Water Stations Along the California Coast .
5. National Ocean Survey, Department of Commerce, Tidal
Bench Marks, California, Part II, Port Hueneme (10/2/62)
and Santa Barbara (6/25/68) [unpublished].
6. National Ocean Survey, Department of Commerce. Tide
Tables for the West Coast, North and South America.
Years 1965, 1966, 1967, 1968, 1969.
7. O'Brien, M.P., 1931. Estuary Tidal Prisms Related to
Entrance Areas. Civil Engineering, v. 1, No. 8,
P. 738-739.
8. Oceanographic Services, Inc., 1965 . Oceanographic
Study of Ventura Marina - Phases I and II.
63
APPENDIX
SOUNDING SURVEYS OF VENTURA MARINA
January 1965 through January 1969
The sounding surveys reduced to 50% and arranged in
chronological order, are in the form of working charts.
They were drawn by the Ventura Port District and were
contoured at a 2 foot interval by the author.
64
65
//
(0
\
\ IT
a* i 4 i $ * $ ^ ^ \ * i" $ C ? f *
«. t*
p >/ . /
\
tHTHAIICt CHAIIHtl »OV'«PI'A>J
x ••
66
a+oo
L
ll-OO
O 0 £ \° <* /V 'J V -v * V <C n* ** •> J
3 < * av £ <f # ,^ £ ■? f 2 ■i 9 * S
< -t i $ v* N* I?' V ** *? '<* ^ ^ * * '
<; <," <,* (,* <C / ,•? a? \ -v0* v« k» s; / f : V
n* • .» ' ^ » • ' 1-
A <c vv -v0 v"" if o> -\ '
5-( >o mit if n i7 '->
« \ * k 1.
0. \f v* vs v<.
r rtV"> \7 17 i\iL, » s
i> v"> n> \* \» \» <\ \» |j
/7 \% n n n n /J, /r
>*. i«
67
7TX H 37
; ,• ;••£< tj i Sf * f J f i* i.
* ^ j ^ \\ ♦*' P * * ; * * ' '
i\ : z s z * : * • ♦
asssl
* \»
S S 4 $ $ * «
* ******
*- 4 4 4 s" * < a
•l *' *4 ♦ +'<•!-?
y ♦* ,• «» A * * < *■
■t »■»* v* <5 i * <
< * / #• /">s V >, . *...* ; * *• * y
"A-
V—V "V.\
i*
VENTURA MARINA
IXIMWI iWNBIl MUNOMM*
scali i r« ioo"
DATCi /0 TUNC ff<5
68
'7
^
Q
fny ■ ■ r -• / / •• / /
• 1 ,7 »?•
. ; VENTURA MARINA
tNTSANfl CHANNCL SD««OIN«S
'j J SCALt : l"« /OO'
i ■'. DATE'- 9 JULY /965
f.j/' ■' DATUM /S MLLW
f'y.
69
1*oo
8*00
9*oo
10*00
ii+oo
lZ*0O
)3*o
T~-
U* £
fc!// 7-4 v\\ \ v;-
i ' j i 3 / S ( S U ■? l i \ A< * > 'l '-"
^/^v*x< A"
k* A$,\*v»V * f "ui"
o
VENTURA riARlNA
INTAAMCI CHAMNfL I0UM0»N#S
lCALl I I' • 100'
DATE- " AUO f965
0AT0/"> 14 MLIW
-fty.
" / >•> j ^
ll /
70
8too
1 + OQ
JO+OOJ
«. "
i mm >■' * * > b
Lx-'
Jim* ?jV v* YKff^v
\ \ \ \
12+00
i /- / \\V
tff"
ill .'. "X s i. \ X \\f, * L t i ■ X • ,,,
jil/,6 , j \ v<- £ ** \\hv' |V 0' >
v i v \ .
71
72
73
4\lH ? 7 'I H'
it / 1
J ,yVfvO»*
■V1 a,' * -v -v . |V ■T. v vv' \* v 0 \° ,. '
/ I '■'* Ij ■ <
Dec. 1 t I<=JCS
VENTURA W/\UUIA
IIVTOONCC CMANNIL 1OUN0IWO5
SCALE I »"• IOO"
o
7^
, "'1 ';' ;. •* J ,v "ill* '* '""
-4 dftfii I /> M<-A(i
>V I' 1*
<l w £ • £ V * *° >* >h
* •» •* i .■♦ «"» 2
*VX*£$ ^ „o ,r * (*£"£,?> <f«,
X-' ■/
tt?a/. **, /*?££
VENTURA riAHINA
(N TRANCE CM»MN€L SOUNDINGS
SCALE: /"= W'
75
8*oo I
9*ooj
11*00
3*4 i
76
■v-
7 + oo'
fl»oo
<J*00
I0 + 001
l+oo
I2 + 0O
1 3*00 1
l+*00,
/5«00|
\
+<r
>° «••
'»v .»,
f'V^Vo"
ifc ,i
9 17
'7
y J ;,*% ^
VENTURA MPIM
(i'H<l«cl tM«»>iti f»u«n»mf
SCALE: T- /r>o
MAflCH 4; /?£6
PATufl IS M.L.I, w.
77
78
7-00
~r
! / , \ -> '' \\\ V
- ""-/..TV
"V V *v,
'. " . i
it
VENTURA MARINA
SCALE: r'«IOO'
APRlWiS 1166
79
7»oo
fl + oo|
9*0O
10*00
U*S2
!2*O0|
)3»OQ
l+»00
iS*oo
IS
-i — f- -n ) \v «? k-v - y A ^° [ ,i> *• v* ^ >* f v* r ^
tv h ,ifc ,, . . .
./<T
VENTURA MAR /MA
INIW^N'.l CHANMtl MUNDMMf
/7 MAY /966
JCAllM'MOO' &«ri/r*' MICW
80
81
7+00
8+oo
1+oo
to+oo
1 1 +00
iz+ooi
l3+00l
~»4.*00f
it »<i
IS+OC
1 V
(5+a+
ill * dl It
'/
P Vn V in * \* ^* ^* v<v ' v ' 7
\
1 I r, I «, M JO \\
it1
a «-
11
' /
>'»
VfrJfURA MARINA
INTAA^r (HnWHIi. UuMl>'>ia}
fit SCAir : ("■ 100'
„,>>'' JULY 18, /96A ►«.«;, .
82
y._2±oo_
B+oo
9+00
10 + 00
11*00
\Z+oo
13*00
I++00
15*00
/
15*8^
J
*» \ v> Wt' I 'vJ *^ <*» "b
la'^jptf ^ * <* / yf^t?:r(
4
- L . 4 *\\/l » S . . • > 4
i // i f'1 •^ i \ ~\ •*
| W M> i A* t* V ^ ^ ^ # i> a* k% P 0 * l<
I /I //Vf / .</
> /
/
wltf J//IH f ' ,* '^Vi
'/,s'*w,\
'V
w)
ventura .Carina
EMTKANCt CHANNEL SOUNOIN&J
SCALE: I" ' IOO'
AUG. 19,1966
PATUM IS D.L.U.W-
83
Mm? i
■ »
1 '«,* tf ■*/'.*» a* *'
. . i L\« j ,»'"/./ . Uii Jill I * ._
- TV ' V\S"
» ' Oft \\\\\\ ,M
/,
;^^'{^f^/^7;^^^^^ *
. !»'
-^a
«*' ■»' is7£«
1 Ml
li- /f
-s-t. Ik
I II
VENTURA MARINA
SCAV.C I «IOO'
SEPT. Z\. )%(,
DATUM It ri L.L.W.
8U
)+oo i \
9-t-oo
10*00
12 + 00
I3+00
ll+OO
IS + OOl
15+0 +
V
•V 1 A *
If *> * * * V
i : ■
4*1
j- & £ £ $ * ^ « »»•
0 * i $ p t* o> <? 1? o? ^ x« x> vi *
\\\ I
I I f\°£$l? S\ •$( <S { \* *^1\1'^1V it
\*
,.\ \ X
17 Itj- It It
85
7+00
1
« 1
8 + 00 |
1
1
9+00 |
10+00 |
11*00 ,
1
ll + OO
l>+00 1
14+00 1
\S+00 1
/ )
15*84-
I .<
J\m\ \ \
\\!k^--« ... — T
['•I Jf/» M,«V '*a
U<» * I. • > 'X"~ *\ k I./ > la » fc »
I
^^
*VV« '
/ a*
2*W
VENTURA DARINA
INTflAnCt CHAIMll ie^--P(l»^|
KAMI ' "■ So'
NOV. 23 IU6
86
7+00
. 8+oo
9*00
10*00
11*00
12*00
13*00
14*00
\S±oo
\s*8+
••r
l/ll ^V 1
>/W/l/ j/%;; ! W
I M\\ \ \ / \ ! i M t I "- — '
*> «J!
VENTURA MARINA
■ HTMANCf CH^MNei. J0UN01M»i
SC*ll: l"»50'
DEC 28, I7feb
PHTUM IS rtt.L.w.
87
it.* 17
ij
J. -J) . ' V
«/ lbl«« .
'3 /f'V
VENTURA MARINA
scalc i r • too'
JAN. 19, I9&7
•»Tu»f it n.c.L.w.
88
^ : j__ « -j^
o> W*^ V J -*
X'
V 1/ "P ■&
<vx0 f>
K
xW A
i? *♦ * 4„» fty
': I i
/
' ///
/
* a
• «
- '3-
fcitfffj <? i* K^ f\£££i$'?$
WSlv >/<? *? ^ ^voV^vvl7
VENTURA MAR/MA
IMT/?/»«Ct CHUNNIC SOUNP/IV4S
SCMCl l"; 100'
FEB. 8, /747
ii ■.
r<\»
89
)5»00|
i s t . iJ iV
VAr**^
II 17
-* — ii__
&8fc-\
MAP' H 3 . 11^7
VENTURA MARINA
(IKTffANCf CNANMCl JOUNOlNCS
SCAlC I"- IOO'
MARCH 3, 196 7
DATUM l| fl.L.l_W.
90
7+00
B+OO
9+00
10+ OO
H+00
IZ+OO
13+00
H-+00
1
" U
i I
)f
Mill ' » ■< 1 ■> ■» "< 1 .P
i \i ' -j >
i 1 1 £ ^ o* £ •$ <? ( *° «W 1 s
:i'-
^
\ / / / ->-io^ v ' ^J
f » @Vv5 <? £ V v* , M? £ £ <?oV£
\"> O \«» \<> \«. \4 . o o 0 o 1 1
'*«**-
•r
i
VENTURA MARINA
tNTRANCt CHANNtU S0UN0l*«S
SCAICH"* /OO'
DATE' Z6 APRIL '67
o^run i% n.t.i.w.
91
la
It'll
It,
sec f"*|M X * * /$#*W'
I /'A iv
V. ^A /.' - ^
V \ \ / ! ^^
• «,' <, c i <<k \< *\-&\ '*> v" >vnV^
\\% '
9--J * ? > + ? i.
£ V* 0 \b* \*»* <> i 0 * 'J*
(C. IS i'
VENTURA MAKINA
|NTt»NCl CM»N»ltl. 50U"0IM64
SCALt I' ■ 100'
DATE: 9 MAY 6 7
OATun IS « I. c.w.
92
e_±po i
9*00
L.
11*00
13*00
I
l+*oo[ \
' 1« J«
I «/ kl/3
gK<
Mill 1 \ . ;'"V mil
Mi/A fc ^:|
if-ll 1 ^ '\ \ll i \
' ! ill. . v\\ X \ / a
"l I1!
a a
ft
/i ii-
93
<$*
00
7*Q
a*oo
9+oo
10*00
11*00
12*00
n+oo
14*00
iS*ocl
15*6+
I fwi „•■ >tf ['> J * * lb * > jp ^ t 1 -I
V\ \. 1 1 l.'A
LaI
w
, / f// / ' Xil
r.'.i
■i I I
I ifc \ ! MY. XX -
i Jllli
r\v i
Wf * V^ *? ,<ll* > tf f ,' tf v**" v* d (f <? ^ ! 7
N
It" »
x^
VENTURA MARINA
INT(tA*4Cf C»»NNll iOUUOINGS
SCAl£: f»IOO'
SEPT 8,1967
is a
9^
VENTURA MARINA
(NTftAMCf CMANMCL 50UN01MOJ
SCALE.- *"=roo'
OCT. 17, 1967
95
t+oo
1*0
io*oo
|l»OQ
U+oo
(4- + 00
IS+oo
!«+•♦
VENTURA MARINA
JNTBANCt CHAMNtL 90U«0'N«t
tCALl | l"s 100'
NOV. ^9. '967
0»Ttwl it M.I..L.W.
96
97
98
7*00
8*00
9*oo
10*00
11*00 I
11*00
0*00
14*00
15*00
IS* B±
\
VENTURA MARINA
CNTRANCC CHANNCL '.WuDINOS
SCALE: l" :|Oo'
MARCH II, /9G8
DATUM IS ML I..W.
99
100
o o 6 s ,p 9 £ j j. J ^o £ x; 4 ,;
/-I. » V\\\-> \ * * ** -v y< •» -\ C) O* * .1
tf if ** ^ ** C ^ ^""% ♦ * V **£ £t."
/
>•?/•*/#«> »<? ** vo% <?
^\>\0 x0 x0 |p „
ill
il/, / / "^ ^"^
\ i
ii
•»* <3f v^ W
' .»' ~'V„< ^18 1^-1?-.
*• y *v • • ^v — i
VENTURA MARINA
(NTItANCi CHXNNIi. SOUIMOINSJ
dCAlC '. '"a /oo'
APR/L /J, 1968
catum i» n.L.L.W.
n
101
7*00
8*oo\
9*oOi
10+001
ll+OO
12*00
1 11K<HI
M 11
<v' *' -V
J/, u • « — >> * * '£)} "L,
* iff \ * *' I/- * ^M L
k'z c fh 1° y * £ -x? f X/V
i 111 I \V i /I i
102
8 + oo
9+oo
io*oo\
II *oo
\2-*DO
fb + oo I
/**oo
l5+oo
I5*8+,
J^^Vv ^ I *£ i? i>
i 'i
j \
» • «
s o> v» v«r <" 4* 3
S£4* <m
+ jjj# & J <t {? *?\*W\*V
• ' Y
<?*y*V ^ ** i ^* •?*•<?<*<?<*<* <A
\rt '""• w
103
TT
1*00
8*00\
9*00 I
10+001
11*00
\z+oo
I3+Oo|
14*00
l5+oo
]s*a±i
s
: %* ^ |a* * y * ^ j* o> * # j * *.<
Vnivft^.i
\0
j T ! .
> 15
•^JLa
4^^^'V^ '^^^vTi
1 Ij
*-
104
7*00
6+oo
9+oo
ID + OO
11+00
VENTURA MARINA
(NTRftMCf CH»«»ll Sou~0iNfrS
SCALS : l' - IOO*
OCT. 9, /968 j
CJfTN l~ JeiT - M C.l.W.
105
106
1-rOU |
1
1
8+oo\
9+001
I
10*00 1
llt-00 1
I
12+00.
1 1 1
ii+ooi \
n-*oo|
15+00 I
I
/
•3'
I
* i * i* •» ■ «•* *• * * «" /*••.* •>
I
\
i r /
1 / '
/ '
I"
\
\
\
* »
\ ?> 1 '<> v* x* v* # # & -J> v^y fr ^ ^ o
v1> v1- 10
•.»!»* "if • <> * *t * * «r *
■w \ * * <w *. v ;v ^ **
^V^A^ «* x* <\ x^W^
XT \\\ * \ \ ">
8 > 5 -\ l„ «, <\\ v A * N^N 0 x* ^ > ^
-+0
'• ii ,
'fe
V
107
108
INITIAL DISTRIBUTION LIST
No. Copies
1. Defense Documentation Center 12
Cameron Station
Alexandria, Virginia 22314
2. Library (Code 0212) 2
Naval Postgraduate School
Monterey, California 939^0
3. Department of Oceanography 3
Naval Postgraduate School
Monterey, California 939^0
4. Professor Warren C. Thompson 5
Department of Oceanography
Naval Postgraduate School
Monterey, California 939^0
5. LCDR Mario E.C. Vieira 3
Instituto Hidrografico
Ministerio da Marinha
Lisboa, Portugal
6. Professor Edward B. Thornton 1
Department of Oceanography
Naval Postgraduate School
Monterey, California 939^0
7. Commanding Officer 6
Fleet Numerical Weather Central
Monterey, California 939^0
8. Commanding Officer 1
Environmental Prediction Research Facility
404 Franklin Street
Monterey, California 939^0
9. Oceanographer of the Navy 1
Hoffman II
200 Stovall Street
Alexandria, Virginia 22332
10. Naval Oceanographic Office 1
Library (Code 3330)
Washington, D.C. 20373
109
11. Dr. Peter Badgley (Code 410)
Office of Naval Research
Naval Research Laboratory
Arlington, Virginia 22217
12. Dr. James S. Bailey
Director, Geography Programs (Code 462)
Office of Naval Research
Arlington, Virginia 22217
13. Dr. Ned A. Ostenso (Code 480D)
Office of Naval Research
Arlington, Virginia 22217
14. Dr. Robert E. Stevenson
ONR Scientific Liaison Office
Scripps Institution of Oceanography
La Jolla, California 92037
15. Commander
Naval Facilities Engineering Command
Command Headquarters
200 Stovall Street
Alexandria, Virginia 22332
16. Commanding Officer
Naval Civil Engineering Laboratory
Port Hueneme, California 93043
17. Director
Naval Coastal Systems Laboratory
Panama City, Florida 32401
18. Dr. Rudolph P. Savage
Technical Director
Coastal Engineering Research Center
5201 Little Falls Road, N.W.
Washington, D.C. 20016
19. Dr. D. Lee Harris
Coastal Engineering Research Center
5201 Little Falls Road, N.W.
Washington, D.C. 20016
20. Commanding Officer
San Francisco District
U.S. Army Corps of Engineers
100 McCallister Street
San Francisco, California 94111
110
21. Mr. Orville T. Magoon
Coastal Engineering Branch
Planning Division
U.S. Army Engineering Division, South Pacific
630 Sansome Street
San Francisco, California 9^111
22. Mr. Charles Fisher, Chief
Coastal Engineering Branch
U.S. Army Corps of Engineers
P.O. Box 2711
Los Angeles, California 90053
23. Mr. Charles Holt
U.S. Army Corps of Engineers
P.O. Box 2711
Los Angeles, California 90053
24. Director
National Ocean Survey
National Oceanic and Atmospheric Administration
6001 Executive Boulevard
Rockville, Maryland 20852
25. Mr. K.C. Klinger, General Manager
Ventura Port District
P.O. Box 1107
Ventura, California 93001
26. Director
Instituto Hidrografico
Ministerio da Marinha
Lisboa, Portugal
27. Biblioteca Central
Ministerio da Marinha
Lisboa, Portugal
28. Director
Laboratorio Nacional de Eugenharia Civil
Lisboa, Portugal
29. SIO Library
University of California, San Diego
P.O. Box 2367
La Jolla, California 92037
30. Department of Oceanography Library
Oregon State University
Corvallis, Oregon 97331
31. Department of Oceanography Library
University of Washington
Seattle, Washington 98105
111
1 5 1 9 Q R
— ^ jl __ o ^
Thesis
V66 Vieira
c.l Time-series study of
sanding in Ventura Harbor,
Cal ifornia.
, ', A,,-
V i e i ra
Time-series study of
sanding in Ventura Harbor,
Cal ifornia.
thesV66
Time-series study of sanding in Ventura
3 2768 001 92773 4
DUDLEY KNOX LIBRARY
Live Music Archive
Librivox Free Audio
Metropolitan Museum
Cleveland Museum of Art
Internet Arcade
Console Living Room
Books to Borrow
Open Library
TV News
Understanding 9/11