Technical Report Series
Number 77-3
SAND STABILIZATION ON THE
DUNES, BEACH AND SHOREFACE OF A
HISTORICALLY ERODING BARRIER ISLAND
Wassaw Island Erosion Study
Part Ill
by
George F. Oertel
and
James L C
Harding
Georgia Marine Science Center ·
University System of Georgia
Skidaway ls1and, Georgia
SAND STABILIZATION ON THE DUNES, BEACH AND
SHOREFACE OF A HISTORICALLY ERODING
BARRIER ISLAND
WASSAW ISLAND EROSION STUDY
PART III
by
George F. Oertel
Skidaway Institute of Oceanography
P.O. Box 13687
Savannah, Georgia 31406
and
James L. Harding
Marine Extension Service
P.O. Box 13687
Savannah, Georgia 31406
The Technical Report Series of the Georgia Marine Science Center
is issued by the Georgia Sea Grant Program and the Marine Extension
Service of the University of Georgia on Skidaway Island (P.O. Box 13687,
Savannah, Georgia 31406). It was established to provide dissemination
of technical information and progress reports resulting from marine
studies and investigations mainly by staff and faculty of the University
System of Georgia. In addition, it is intended for the presentation of
techniques and methods, reduced data and general information of interest
to industry, local, regional, and state governments and the public.
Information contained in these reports is in the public domain. If this
prepublication copy is cited, it should be cited as an unpublished manuscript.
INTRODUCTION
This report is supplemented by two earlier reports on the sedimentary framework and water-flow characteristics adjacent to the north
end of Wassaw Island, Georgia.
The purpose of this report is to
describe the effects of synthetic devices on the sediment budget of a
historically eroding area of shore.
Three devices were used to modify the sediment transport patterns in order to control erosion.
Snow fences were placed on the
backshore portion of the beach in a barren area covered with scattered
patches of beach straw.
Durabags filled with sand were placed at the
low water line between the foreshore and a shore -parallel spill-over
channel.
Mats of artificial seaweed were tested on the foreshore,
and the shoreface at depths of -1 m, -2.5m, and -4m.
PRODECURE
On 12 December 1973, snow fences were installed on the north end
of Wassaw Island (Figure 1).
Four 50 foot long sections of snow fencing
were established normal to the direction of dominant winds (Fig. 1).
A simple design scheme was used to make comparisons with the more
elaborated designs used and suggested by Savage (1963), Savage and
Woodhouse (1968), Jagschitz and Wakefield (1971).
The four sections of
4-foot high fence were surveyed in with respect to established markers
in the stable dunes.
Around each snow fence, twelve survey stakes were
imbedded into the sand surface.
Biweekly measurements were made of
each set of stakes to determine the exchange in the thickness of the
sediment carpet in the adjacent 168 square meters.
6
"----" low tide
~ 1968 erosional scarp
-
profile transects
snow fences
- - _--- dura bags
j//// survey areas
meters
0
100
50
150
200
I
,•
tv
·~·~
....
.....
....
~
..._
.......
9
*a
......
.....
.....
* seagrass
plots
*c
FIGURE 1 - Location map of study area, showing positions of profiles, snow fences, durabags, seagrass plots
and survey areas.
3
The sediment budget of the beach was approximated from biweekly
profile surveys that were initiated in November 1973 (Appendix B).
Six profile transects were mapped at the north end of Wassaw Island
(Fig. 1), using a modified staff and horizon technique (Appendix C).
The data points along each profile were 2 m apart and the vertical
measurements were surveyed to
±
1 em.
After 8 months of profiling,
a checkerboard pattern of sand bags was placed at the toe of the foreshore between profiles 1 and 2 (Fig. 1).
The sand bags formed a
semi-pervious dike that was intended to serve several functions toward
preventing beach erosion.
The structure was intended to dissipate
wave energy and to function as a subaqueous dike that would hold sand
on the beach.
The structure was also to help maintain the integrity
of a shore-parallel tidal channel which supplies sediment to the north
end of Wassaw Island (Oertel, in press).
Beach profile surveys continued
for approximately 1 year beyond the initial implacement of the pervious
dike.
Patches of seagrass are believed to sufficiently disrupt the flow
of sediment laden currents to cause deposition of sediment.
Seagrass
decreases current energy due to bending of fronds, increased bottom
drag, internal deformation and refraction (Wayne, 1974).
Four plots
of artificial seagrass were tested adjacent to the north end of Wassaw
Island to test their potential as sediment traps.
Plots were placed in
the intertidal zone .25 miles (.46 km) offshore at -1 m depth, 1 mile
(1.85 km) offshore at -3 m depth and 3 miles (5.56 km) offshore at -6 m
depth.
Seagrass plots were 1 x 10m and fronds were 1.1 meter long and
supported by 4 inch diameter styrofoam floats.
18 to 24 fronds per square meter.
The frond density was
Seagrass plots were fastened to anti-
scour blankets (Sea Mats) and secured to the seafloor by pins and weights
3 meter
depth
at B
4----------------------10mete~---------------------------.
6meter
~'
depth
at C
~ 11
11
~
~
polypropylene
fronds
~
~ ,·
; ; t4
. '.i:/).~
1~1"\.-.1~
~
~
.
J~
FIGURE 2
~__
,_
Sketch plan of seagrass plots.
"""
5
(Fig. 2).
The effectiveness of plots was evaluated by SCUBA obser-
vations.
OBSERVATIONS
The largest quantities of wind-blown sand were trapped during
the first month following snow-fence installation.
At the survey area
of fence A, approximately 27 cubic meters of sand were trapped during
the first month and after 1.5 years of a total of 69 cubic meters of
sand was trapped {Fig. 3).
Snow fences B, C and D were along the
inlet shoreline, and were stepped back from the ocean shore .
Initially
during the first month, profiles B, C and D collected 36, 35 and 37
cubic meters of sand, respectively.
In the pursuing year these volumes
all increased to 50 cubic meters only to be followed by a deflationary
period, which decreased volumes to 28, 39 and - 1.0 cubic meters during
the last six months of the 1.5 year .
Sand accumulated on both sides of the fences.
On the seaward
side of the fences, sand accumulated in broad flat prisms .
On the
leeward side of the fences, sand formed peaked ridges with steep slip
faces.
After the initial month, maximum dune heights were . 5, .6, .4,
and .6 meters at area A, B, C, and D, respectively.
During the study
period, maximum heights achieved at areas A, B, C, and D were 1.2, . 9,
.7 and .8meters, respectively.
Initially, dunes that were formed by snow fences were barren and
had active slip faces.
In the early spring of the first year, seed-
lings of the pioneer plants Salsolsa sp. and Panicum sp. appeared in
the area around synthetically formed dunes .
By late summer of the
same year substantial clumps of Uniola paniculata and Panicum amarum
were on the margins of the dunes, but the crests of the dunes were
80
SNOW FENCE VOLUMES
I
7ol
60
... .-.
· ·····•····· AREA A
··- .. -··- AREA B
------- AREA C
AREA 0
~
.
.\
::
50 1-
I
a:
LLJ
t-
40
.... ..
/:
LLJ
~
u
m
:::::>
u
.'J
../.
}": Y.....') '
'
.'
1
·, .· . . ;:: ':.
.
~·:
. ...
\ 'J: ,\.. ~ .t. -'I . :. .:
30
.
;·..
:.
) ,' \
.:·
' ·.·.
I
'
'
,. ..
,,
:./. ~-- J
,
\...-
.···':
'\
.
:
..
· , ..
__ ........ --··'
! /
'
,.
, "'
-.
-
I
·. , ,
0"1
...
'.
'•'
I
:
\
~
'..:
:.·
:\.
J '•/
\/;
. I
''
:•
•"
I
I
I
I
20
10
0
~#
\
.'
~
! :
•W
,, . ;,
.·v,f .. . /"
-
.oL\
'
''
I
\.
'
'\
en
..
'
'\
\
ll/
I
',
2
3
4
5
1974
6
7
8
9
10 II
12
(MONTHS)
I
2
3
4
1975
FIGURE 3 - Graph of volumes of sand trap on the vicinity of snow fence A,B,C,D.
5
6
I
7
still barren.
seaward of
A 50-100 yard wide zone of barren beach was exposed
snow fence areas A and B, however, because of spit configura-
tion, the beach was considerably narrower adjacent to area C and D.
~s
the spit adjacent to areas A and B accreted in 1974 and 1975, the beach
adjacent to C and 0 narrowed, leaving only a very small source area for
the sand dunes in areas C and D.
Deflation of sand in the dunes from
area 0 began in September 1974.
Erosion of sand from the dunes in area
C was first observed 6 months later in February 1975.
By late summer of
1974 and early spring of 1975, pioneer vegetation and beach straw berms
began to appear on the barren beach of the spit.
These structures
trapped relatively large quantities of wind-blown sand and prevented
the transport of sand into the test areas.
Data from previous surveys indicate that the tidal channel adjacent
to the beach is a very important supplier of flood water and sand to the
northern end of the island (Appendix A).
The pervious dike made of sand
bags was located on the landward side of this tidal channel and prevented channel silting by inhibiting the flow of beach sand into the
channel.
A one-year survey period was made following the installation
of the snow fences and prior to the installation of sand bags.
This
survey illustrated a 1.6 acre (.63 Hectare) increase in shore area
(Fig. 4).
Periodic surveys following the installation of the sand-bag
dike showed that the shore continued to accrete.
Periodic surveys
were made for the one-year period of implacement, and continued for a
3-month period following removal of the sand bags.
During the one-year
and 3-month period, the beach accreted an additional 6.6 acres (2.7
Hectares) and by comparison there was approximately 4 times as much
8
~
-
N
I
meters
25
0
50
75
100
ONE YEAR DURATION
WITHOUT BAGS
(11/73-10/74)
t
1.56 Acres
ONE YEAR DURATION
WITH BAGS, PLUS 3
MONTHS WITH BAGS
REMOVED•
( 10/74- 2/76)
+ 6.56 Acres
NET CHANGE
( 11/73-2/76)
t
8.12 Acres
•BAGS WERE REMOVED IN LATE
SEPTEMBER 1975
FIGURE 4 - Map of the northeast part of Wassaw Island (Fig. 1) showing 1968
scarp, and the positions of the 1973, 1974, 1975, and 1976 shorelines.
9
beach accretion with the pervious dike in place, as before installation.
In all, approximately 8.12 acres of new shore accreted from November 1973
to February 1976.
At the initiation of the project, the shore that faced the ocean
between transects 1, 2, and 3 was eroding and dunes along the back shore
were truncated.
In the nine months previous to the installation of the
pervious dike, the backshore accreted 10m.
Seven months after the
installation of the dike the backshore had accreted an additional 24m
and foredunes were developing on the scraps of the truncated dunes.
While the beach was advancing seaward, it was also advancing in a shore
parallel direction toward the axis of the Wassaw Inlet.
Residual flood
currents on the beach front were predominantly responsible for the
transport of sediment toward the axis of the inlet channel (Oertel, in
press).
Spits initially formed near profile 3 in the lower part of the
intertidal zone.
Redistribution of sediments by flooding current caused
spits to curve landward and move toward transects 4, 5, and 6.
Swash
processes also caused the spits to move up the beach face until they
11
Welded 11 onto the shore near the berm (Appendix A-9, 10, 11, 12).
The
qualitative and quantitative development of the shore between transects 1
and
6 is illustrated by graphs and profiles in Appendix A.
The artificial seagrass plots had limited success in trapping sand
on the foreshore and shoreface.
The seagrass plot established at the
foreshore trapped 30 em of sand within the first week.
However, the
action of breaking waves entangled most of the fronds so that fronds
were only able to float approximately 30 em above the seabed.
After
10
two weeks this plot was removed, untangled and moved to an area approximately 0.2 miles (.37 km) offshore and fastened to the seabed in a
shore-parallel orientation.
Within a month, the base of this plot was
covered with 3 to 15 em of sand and a shallow depression (20 em) formed
in the lee of the plot.
After three months, numerous encrusting organisms
had weighed down many of the fronds and no additional sediment had
accumulated on the mat between the fronds.
After six months, there was
a general lowering of the shoreface within one mile of the shore.
How-
ever, sediment on the seagrass plot remained in place and created a
topographic high . A late winter storm eventually removed the marker
buoy from the plot and buried all traces of the antiscour blanket and
frond materials.
The third plot of artificial seagrass was located leeward of the
shoal and .8 miles (1.48 km) offshore.
The seagrass plot was installed
by first lowering two 100 lb. weights to the sea floor with 1/4 11 polypropylene line.
The upper ends of the lines were attached to two
corners of the seagrass plot and pulled taut.
The line and plot were
slowly lowered to the sea floor keeping both taut.
Two 100 lb. weights
were also used to secure the trailing end of the seagrass plot.
Once
the plot was on the bottom and marked with a brightly marked surface
float, SCUBA divers were sent down to stretch out the mat, pin it to the
substrate, and untangle any
fl~onds
as was necessary.
Diver work was
made difficult because of high turbidity causing approximately 611
visibility and surges from sea swells that tended to roll the divers
every eight seconds.
The initial implacement took approximately 1-1/2
11
hours and final securing took approximately 1 hour.
The plot was located
in -2.5 m of water (MLW) and was oriented along a 243° bearing.
was slightly oblique to the 230° orientation of the shoreline.
This
Installa-
tion of the plot was undertaken at half tide when ebb currents in the
main channels were achieving maximum speeds.
However, the installation
site was shielded by a sand shoal and current speeds were almost slack.
SCUBA observations after one month illustrated some scour and burial at
the edges of the antiscour blanket.
Fronds were not severely tangled
but extensive floral and faunal communities had attached to many of the
fronds.
In the pursuing month, a severe northeast storm hit the coast
and tore the marker cable from the mat.
Numerous tracks with a pre-
cision bottom sounder revealed no traces of the plot.
The fourth seagrass plot was located approximately 3 miles (5.56 km)
offshore, and leeward of the marginal shoa l 1 mile (1.85 km) south of the
channel.
Installation techniques were similar to those used for the
third seagrass plot.
The long axis of the plot was secured at -6 m (MLW)
and oriented along a 315° bearing.
The seabed was composed of coarse
sand and shell fragments which at the time of installation was shifting
in response to strong waves surges.
After one week SCUBA inspection of the plot was made .
No burial
was noticed except for a few small lenses of coarse material in the
center of the mat.
The pins appeared to be elevated slightly, suggesting
a lowering of the seabed below and adjacent to the mat.
tions after one month revealed little change.
SCUBA observa-
SCUBA observations for
the next three month period were cancelled because the marker floats
12
were missing and an extensive search with a precision bottom sounder
did not show any traces of the plot.
CONCLUSIONS
The flood tidal channel adjacent to the north end of Wassaw Island
(Oertel, in press), appears to be the major factor controlling shore
accretion.
When the channel is open sediment is transported to the north
end of the island.
Spits on the north end of the island prograde north-
ward and curve into the Wassaw Sound.
Data collected during the study
periods indicate that a properly oriented pervious dike constructed of
sand bags may have had a positive influence on keeping the channel open.
As spits prograded toward the axis of Wassaw Sound they begin to curve
landward and move up the beach slope.
The eventual welding to the shore-
line increases the area of exposed beach.
Onshore winds transported
the dry sand on the exposed beach surface until it came in contact with
obstacles such as mounds of beach straw, plants, dunes or snow fences.
The accumulation of sand around these obstacles formed foredunes and
dune ridges (Oertel and Larsen, 1976).
Snow fences were particularly
successful in trapping wind-blown sand behind the broad, exposed areas
of beach created by rapid spit development.
Snow fences adjacent to
the narrow sections of beach or beach that was fronted by advanced
sediment traps, such as straw berms, plants or snow fences, were not
successful in developing dunes.
Small plots of artificial seagrass were not effective for trapping
sand on the open ocean coast.
The turbulent motion of breaking waves
tangled fronds in the foreshore area and reduced their efficiency as
13
energy dissipaters.
In the offshore areas, plots had only local effects
on sediment accumulation.
The loss of energy produced by bending sea-
grass fronds permitted small amounts of sediment to be deposited on the
mat surface at the base of the seagrass.
However, adjacent areas of
sea bottom illustrated no obvious changes.
During periods when the
shoreface was lowered by some physical event, the seagrass mat held
sediment in place forming a topographic high.
The original intent of the 1 x 10 m seagrass mats was to artificially induce the formation of sand waves that would eventually migrate
shoreward and supply sediment to the beach.
Insufficient quantities
of sediment collected on mat surfaces to form these mounds.
The maximum size of seagrass plots that could be handled and
installed was 1 x 10m, however, this size was relatively insignificant
with respect to the beach-shoreface system on the north end of Wassaw
Island.
Naturally occurring sand waves in the area are at least
2 x 50 m and generally occur in sets of three (Oertel, 1971).
In conclusion, the marginal tidal channel at the north end of
Wassaw Island appears to be a critical feature controlling the development of the shore.
We feel that submarine pervious dikes such as those
constructed with Durabags are useful structures for keeping the marginal
channels open.
When these channels are open, sediment is transported
to and deposited at the north end of Wassaw Island.
Snow fences
appeared to be an effective means of trapping and storing large quantities of sand on the upper beach.
However, fences were only effective
where rapid beach growth produced broad areas of loose sand available
14
for eolian transport.
Snow fences were not an effective means of
building the beach in areas where the beach is eroding and the shoreline
is retreating.
Small plots of artificial seagrass had no obvious con-
tributing effect for producing a source of sediment for the beach.
However, additional research on larger plots of such mat-frond systems
may give more positive results.
ACKNOWLEDGMENTS
This project was sponsored (in part) by the Georgia Sea Grant
Program, supported by N.O.A.A., Office of Sea Grant No. 10-32-RR273-077.
Oceaneering International, Inc. of Houston, Texas supplied the sea mats
and durabags.
The frond material was furnished by the Patchogue-
Plymouth Company of Atlanta, Georgia.
The
u.
S. Government is authorized
to produce and distribute reprints for governmental purposes not withstanding any copyright that may appear hereon.
The authors acknowledge
with appreciation the assistance of R. Brokaw, C. Chamberlain, M. Larsen,
D. Perlmutter, and R. Wallace.
15
REFERENCES
Jagschitz, J.A. and Wakefield, R.C., 1971, How to build and save beaches
and dunes:
Preserving the shoreline with fences and beach grass.
Bulletin 408, Rhode Island Agricultural Experiment Station,
Kingston, Rhode Island.
Oertel, G.F., 1971, Sediment-hydrodynamic interrelationships at the
entrance of the Doboy Sound estuary, Sapelo Island, Georgia.
Ph.D. thesis, University of Iowa, Iowa City, Iowa.
Oertel, G.F. (in press), Idealized geographic cycles in ebb deltas and
related patterns of shore erosion and accretion.
Journ. of Sed.
Petrology.
Oertel, G. F. and M. Larsen, 1976, Developmental sequences in Georgia
coastal dunes and distribution of dune plants.
Bol. Georgia
Academy of Science, 34:35-48 .
Savage, R.P., 1963, Experimental study of dune building with sand
fences. p. 380-396.
~Proceedings,
8th Conference in Coastal
Engineering.
Savage, R.P. and W.W. Woodhouse, 1968, Creation and stabilization of
dunes. p. 671-700.
~Proceedings,
11th Conference on Coastal
Engineering.
Wayne, C.J., 1974, Effect of artificial sea-grass on wave energy and
near-shore sand transport.
Soc., J. 24:279-282.
Trans. Gulf Coast Assoc. of Geol.
16
APPENDIX A
A-1
9 August 1973 Survey
A-2
26 November 1973 Survey
A-3
13 February 1974 Survey
A-4 19 April 1974 Survey
A-5
12 July 1974 Survey
A-6
10 October 1974 Survey
A-7
13 December 1974 Survey
A-8
A-9
6 March 1975 Survey
29 May 1974 Survey
A-10 21 August 1974 Survey
A-ll 11 February 1976 Survey
A-12 10 June 1976 Survey
fort ruins
~[)
I 4
'
"·,
"\
\
""
"'\
'
\
............"-.,
, "'·--.. . . _
..............
9 AUGUST 1973
1-'
· ........_
',,
-....!
"·"'""
',,
""" '\
',,
',
', \..
l;
,f.·"
If"
// ...
;.·....
1/ .
/.· .·
f.:
!. :
1/ .
low tide - hioh tide ···· · · ·
straw dune - · veoetation - - - - 1968 erosional scarp
snow fences - -
If.··
ll
II:
//;
/,""
~
--METERS
0
25
50
75
100
A-1
18
N
I
c:!:
······· ·······
./
/
.-
//
/ .
/
.
I
I
..
I
c
-~
I
I
I
I
II
,
I
I
~-
··...... .
'':::::::::·::-,._
,...,.~
I
'"'::::::;.-
/
I
.
.
I
I
/
.
/
········
·- ~--.:.~.......,
·-......
/
/
I
/
/
I
I
0
Q
/
10
,.._
I
I
(/)
a:
LLI
1LLI
0
10
:1
10
(\J
0
=
*
e fort ruins
4;D,
r>i ~
',,
....
',~,
'~~.
.>-"-.
"·',"'·
-·
....
\:::-~-\\~ --'\.\
',',
'\
l,
'--,,
\
\\\I
. . . . . .......... ..........
',,
13 FEBRUARY 1974
I-'
1.0
\
',,,'\ )
I .
)/
I
II .
I
I
/j
.
/I
/I .I
'/
I.
I('·
low tide-hiQh tide ...... ·
slrow dune - ·veQetotion - - - - 1968 erosional scarp .......,.......
snow fences -----.
,I
II
METERS
0
25
50
75
100
I
I
.
A-3
20
0
Q
..
c:
·;;
.
-0':>
::
A I~ ! :_.
W« . .
<!}
.
I()
r-
en
0:
w
.....
w
0
I()
~
I()
(\j
0
21
0
Q
0
It)
It)
N
/
0
22
.·
"\'-.)
....
.
·.
/
,,..-·- ·-
/'
I.
:
.' I
(
if
."
I
.·?,\
.Jl
I
.
,. :/J
.
............
'\
·..
-·-·- -
/
"
'-., .........
., .,
,,,----------------.....
/
............... ..............
~
_
-.. . ·-.. . .
,,
.....
)/
!/
r
)
.
.
..........
------:'
I
I
0
J
Q
I /
I /
I /
.
I/
1/
I
.-....-~
;/
. /
f/
a::
LLJ
l%l
I()
N
0
1-
u
0
Q
0
23
.
·················
.:-.---.... '-...
.·
·--·-·-
j/
.. . .___,"""-
... /
... /
.....
.............
/
,...,....
: .
\I
/ ..
/
.' \ I /
I
:' ) ~
. . .- !
·~
I
I
I
.
J
~ :
.:; I
/
/
!
.··/
..../..··'/
.
. .
....
/
//
/
/
-----........... '"'., '"""-
.
· ..
. . . . . . . . . . . . .. . .__,_ ·
'-..
........
I
/
/'
/
~
/
""'·":~
I
i~... . . . (;
itA:
---------------
...
I
0
Q
I
on
,._
en
w
1w
a:
0
on
~
on
N
/
/
0
c:/
fort ruins
(iD»
"·
-·.
""'-..
'--·
I
· ...
..........
·-....... ........__
.
:.._
-·- ·- ·---
--·- .
""'-. ...._ ·.....
', ' ' ' , , , ,
_______
"_
-,',
__
.""'\
'"-.
, __
\ '\
\.
\
\ \
I
I
I
1
6 MARCH 1975
\
I
I
I
II
:
I
!
J
I
I
I
I /'
/
,f'
1:
//
low tide-hiQh tide
straw dune - ·vegetation----1968 erosional scarp ....,...,...,..
snow fences --...
//
,fi
/ .
t/
t/
~
METERS
0
25
50
75
100
l"
/
!'-)
~
.
.
/
.
A-8
25
··· ···· ·········· ··.
/-·- ·-·-.
/. ,.,-------................................"-....... .
.
.. I r
. . . . . . . . . ·" ·,
.........._
;
.
I
',
. . II :
I /;
I :
'........
. I
I i
I
I
.
I
I t
"
'--,,, ·" ·"--
/
/
_____.
."
'--,, ' , ."'-.
',, "'-.."
',,,, '
',
I ! /
.
I
I
I
I
I /
I /
I /
.
.
.
I/,
/
.
/
I
0
Q
,._
I()
I
I
CJ)
a:
w
w
1-
/
::E
I I/
I
0
I()
I
I()
N
en
N
0
26
0
I
cl:
./ ·- ·- ·-........ ..........
······.
'".. . . ._
r\...,...,
~---------
..
.
/
; .,
.
:
:
:
I
. I
) I
I
--
'
'
.. !' ,'
I
. ..._
',,
'
I
. I
I
. I
·--......---.......
'-....._
I
. . ! 'I
.
. ........_
.............
/
·-......._
',
.
..........
.,
· ..
."-.
'
',,
· ..
·,
.
',
I I
I /
.
.c
I
.
·~
~~ ..
-~
. . ~ .I
I
;
I
/ ( /
I \
I . .'>
I
I.
;·
,/
'
0
Q
,~
I
.
I
I
/
/
I
:I
(/)
I
.....
a::
w
w
0
10
::IE
10
N
0
27
......
......
I
c:(
- ·- ·- ·- ·--
/
I
I
/ "
/
·-
..........._,_
.............
..........................
..........................
/---------------I
,'
.
I
'
iI·...._.......... -
1
,'I:
.·· ·, i /
" ·"
.... ,
."""
................
,..--__.
',
."""
'-,
'',,,_...__
. . :· i /
I \
i \ /
..,
I
·~
~d
··. ..
/.
.
:' 4
'
Q
I
,...
I()
I /
I /
/
I /
I
'
0
I
I
I
I
/
I
..i/ ,/
... I
').... <'I··· ·· ; · /
I /
I :
i /
I
en
a::
/
LIJ
1-
LIJ
>a::
<f
:J
a::
0
10
~
I()
N
aJ
LIJ
u.
0
28
0
Q
"'
w
1a:
w
0
I(')
::t
I(')
N
w
z
...,:::>
Q
0
29
APPENDIX B
WASSAW BEACH PROFILE OATS
B-1
Profile 1, 1973-1974
B-2
Profile 1, 1975
8-3
Profile 2, 1973-1974
B-4
Profile 2, 1975
8-5
Profile 3, 1973-1974
8-6
Profile 3, 1975
8-7
Profile 4, 1973-1974
8-8
Profile 4, 1975
8-9
Profile 5, 1973-1974
B-10
Profile 5, 1975
B-11
Profile 6, 1973-1974
B-12
Profile 6, 1975
8-13
Profile Volumes 1-6, December 1973-June 1975
8-14
Beach Section Volumes, November 1973-July 1975
B-1
Nov DEc. 9
N · 25
(3
ocr ov.
<37o 55m3 1
o . 25 11 (3 m3J
SEPr cr. II (34t m3 36m3 I
A
Sf:p. 3o <33 (332
UG. 23
~!><
JULy
~UG. 9
,o,
r. 13
J
(3 9m3J m3J
(3q3m327m3J
~ (32 3 (m3~6m~J
JuN/ULy
28
(3 1
)
MA" JUNf:
(317
6m3
' 31
lq (3 m3 J
)
MAy
17 (350m348m3)
AP
(3
(33... )
.
APR
R. 22 2 6m3 -.m3)
M. 7
(3
)
·
(32o 40m3
MAR AR.
1
22 (
.q
3 m3
~'"F:8. 2o (313m' 29m3
~
~Ay
(313m3)
JAN JAN. 22
~"?
~
DF:c
0 .9
(
(3
F:c
28q 25m'
. q · 20
m'J
Nov. lq (324 (23q m3
w
( 3(( ';;,331
0
I
300
250
(J)
a:
w
~
200
w
::E
;::
150
w
u
100
z
~
I
WASSAW BEACH
PROFILE I
0
10
50
0
20
30
40
50
60
METERS
70
80
90
100
110
120
'!\.V:J
~
JULy 21 (35o
JULy 2
(3?1 m3 J
JUN£19 (367m3)
JUNE 4 (35om3 )
.
B-2
m3J
.
1
MAy 2
(369m3 J.
APR. 24 (351m3 ).
8
F£ · 27 (35om3J
F£e. 13 (352m3 J
.
JAN . 2? ( 348 m"J.
250 r
w
200
~
(f)
a::
w
1-
150
w
WASSAW BEACH
:::!:
1-
z
100
PROFILE I
w
(.)
50
0
0
10
20
30
40
50
60
METERS
70
80
90
100
110
120
Nov DEc. 9
ocr
. 25
SEpT
T. I I
(3
(33 4
Nov.
oc 25
r11
3
07 lll J
(3
I))J)
3
32 1 1113 29 lll )
lJ2
I
r;.PT I 337
o,J
. 3 (3 11!3)3
,0)
JULy UG.
(343
lll
2
JUN/ULy
l29 5
JU 28 ( 3 ( 32
)
.
MAy 31 NE 14 26 1))3 16 1113)
._
AUG
"\"'
S" · 3o r
A . 23
I~
9
B-3
·
,:5
~~I,;)
MAy 3MAY 17 (374 (369
l!l3J
3
A
(
(3
lll )
APR PR. 2
308 3/ 1))3
M · 7 ( 2 ( 3 lll3J
MAR 4AR· 22 3071ll34191ll3J
FEe ., (304 (31Bill3
J
"\":>
~
. ..
JAN 9AN. 2.,
.
..
DEc DEc 2 (25o
.4 . 0
Nov. 14 <3o4 <231
(2 11)3 )
o (
11)3)
.
I.
)
304 1))3
(3
14 1))3 1.
11)3)
,3 I
8211)3 l
w
N
350
300
250
IJ)
a::
w
w
200~
::::E
1-
150
1-
z
I
WASSAW BEACH
PROFILE 2
0
10
w
u
100
50
0
20
30
40
50
60
70
METERS
80
90
100
110
120
130
"\.(r;)
,~
JULy 21 (329 rn3
JULy 2 (332m3)
JUrvt 19 (322 rn3J
JUrvt 4 (313 rn3 J
·
(315 rn3 J.
MAy 12
APR. 24
B-4
(307 rn3 ).
Fta. 27 (36o rn3J
Fta. 13 (36a m3 J
•
JArv. 27 (363m3 J.
300
250
C/)
w
w
a:
LLJ
1-
200
LLJ
~
-
1-
z
150~
LLJ
(.)
I
WASSAW BEACH
PROFILE 2
100
50
0
0
10
20
30
40
50
60
70
METERS
80
90
100
110
120
130
34
:X:
u
~
r<l
ID
W
:;!;
::::!
<l
(f)
(f)
<l
lJ._
0
a:
a..
:;!;
2
Sl:l]l3 Vj ll N3 ~
~
B-6
JULy ~ULr 21
<~·J
~
JU•• JUNE
I 701 I633
••E 4
19
tn•
tn• J
41Ar
1682 16BI
•
AP
12
tnJ I
I.
Fl. 24
1693
"'~
161:;,. , .
4l4f1. 11
FEB. ~EB. 27 1636 tn• I
~:?
JAN. 27 1666
tn•
350 r
ls-, 7 , .
300
IJ)
a:
....
I-
250
~
200
...
1-
z
....
w
WASSAW BEACH
U1
PROFILE 3
150
0
100
50
0
0
10
20
30
40
50
60
70
80
90
100
110
120
METERS
130
140
150
160
170
180
190
200
210
220
230
B-7
Nov 0Ec.9
1
ocr Nov.~; rrsc 7<o .,,
AUG SEpT 13
JUly~~G. 9
11."'
JUoo JUly
"'Ez
MAy 3JUNf
AI
I (
AfA)' 3 AY 17
1739
r
"''!ss "''
f813rn~7? "'"
17
J
l83s.,/<.,•
· <3
.fJ
"''J
17
· <s
SEProcr"
. 3o
--
184{; rn"}
11 18nA
...,rn,
~. 17'1c C,:,<}? .,!
A
APR
PR ?
. 22
16
178
---------
~~rl
}
83 tnl ' thl
MAR AlAR , 17c/706 .,:
F 4 · <c Is
Ffs fB. , ls 60 8< .,,
"''!
.~
..:0
(7
rr,J'
~II.N, 22 t ?'03 rn~2 rnl
Ofc <o l~s 1 ~~09.,!
JA't.
"'"'
.fJ
Nov. 14
~
rsco ... ~
400
350
a:
300
,_w
UJ
:IE
;:::
z
UJ
u
WASSAW
250
BEACH
PROFILE 4
200
ISO
100
5: ~
0
....
I
I'
!I
450
V>
~ ----~
'~-
(?
77'4rn.s6~fl'tl
10
20
30
40
50
60
70
80
90
100
110
120
METERS
130
140
150
160
170
180
190
200
210
220
221
w
"'
B-8
/\.'0
,~
JULy 21 (7' "1 rn>
JULy 2 (73"1 rn>)4
JU/Vf: 19 r711 rn> )
JUNe 4 rsaa rn• J
·
~AY 12
f7sl rn• J.
APR. 2"1 ( 709 rn>
~AR.
Ff:a
II ( 735 rn> J
~3ca,. 7sa
27 f7ssrn• J.
·
rn• J
JAN. 27
f77srn•
~00
250
rn
0::
w
w
I-
:l'
w
-...J
200~
150
WASSAW BEACH
PROFILE 4
I
I-
z
w
u
100
50
0
0
10
20
~0
40
50
60
70
80
90
100
110
120
METERS
1 ~0
140
150
160
170
180
190
200
210
·2 20
230
IVovDEc. 9
IV . 25
(5
ocrov., rs-,489"'1
0 . 25
(6 "' )
.
Seprcr. '' 1558 os "' 1
Au Sei>fo r5 .,'54; I ·
B-9
G. 2.3 · 13 ( 2"' Ill
JU AUG . (613 556 I
LY
9 (6 "' ) "' I.
2S
JUIV~ULy It
'i1A:.
(549 !-,Ill )
JUIV 28 (5 (Got )
.
!!}
-:: 3t E 14
)"' J.
MAy AY
(633 Og Ill )
A 3
(5 "'I
.
APR PR. 22 (584 66 Ill )
"' . 7
(5 "')
.
MAR AR. 2/583 86 Ill)
F .4
(5 Ill )
.
Fes
Ea.
2ol572 73 "'1
J .5
(5 tnJ)
.
JAIV
2/593 82 mJ
1.4
t-,
~
!!!
,.:.c._--..,
~~6"'
r
~~
~IV.
"'JI.
\
350
w
00
\
""" '---"'------------
300
........ ~
250
WASSAW
rJ)
a::
1-
200
"·
......,,
'-.......
~
BEACH
PROFILE 5
UJ
:::E
1-
150
z
UJ
u
1
DEc
(S (59:: I
· 20 28mJ mJ
Nov tq
1'162 mJ
I I
I S6g
UJ
/""'
100
50
0
0
10
20
30
40
50
60
70
Bo"
90
100
METERS
110
120
130
140
150
160
170
lBO
190
B-10
Zl
'\'0
~
JULy
(544
JULy 2 (582m3}
JUNe 19
m3
66
JUNe 4
ml}
rs-,8 rs
rsa., ,,
"'Ar 12
APR. 24
o\fAR. II
(So-,
m3J
.
m3
(592 m l }
Fee. 2"! l58s , , I
Fee. 13 r583 , , J
•
JAN. 2"!
(S"f6m3 }.
300
(/)
250
a::
~
~
w
260
~
WAS SAW BEACH
PROFILE 5
150
"'-----~
\~
~
(.)
100
50
0
0
10
20
30
40
50
60
70
80
90
100
METERS
110
120
130
140
150
160
170
180
190
Ill
w
\.0
Nov 0'<c
N . ciS · 9
0
B-11
c; i?:sOV. '' f:SJ9 r:sJo
ocr r:s r:s "'', "''l
Sf<~'>.-,.J
JI(JG Sf<pr 0 ( :J
f:SJ
.
c?
· IJ
~
~
"uN'<
"uLr
"'', "'' 1
J
ce If r., 'I? r:s,<?,,
UNf< ,., f 'I?? (:J,.,"' ' J
J,
Af4r
j
r:s1c r:sJ6"''J
"'Air 4 l' I?
~?4p~-c2
4p
(
~8J (:J DJ"'' '
"'4~ ~4~ cc r.,8 r.,?.,"''' "''1
~">)
~
"''J "''J.
:s
JUt_~'i?4UG·92 J (•~J f:S~"''1 "''J
6
..,
'
cJ :S~
II
''<s.:s''<s·co r:sO:s r:s09""'''
J
"'''
"''
"''l-
e,,
1
""'"'. 9""'"' 22 r:scc r:s "''' "'''
Doc Dfc 2 r.,6 r:sc"'''
I
No,},., . ,0:s,:s
., "''J ""''1.
r.,J9
r.,?;'' "'
"''
350
"""
0
300
250
~
:I
200
....z
150
u
100
""
t
WASSAW
I
BEACH
PROFILE 6
50
0
U
IU
iW
~U
4U
:>U
t>U
/U
HU
'JU
100
METERS
110
120
130
140
150
160
170
180
190
~~..~
~
JIJL'r 21 (Sio 1113 J
JuL'r 2 !sao m3
·
1
J(JI';£: 19 ( 576 m3).
JIJNE 4 (552m3 )
·
1
(524m3 J.
MA'r 2
8-12
APR. 24 (567m3 I.
MAR. II (524 ml 1
Ffe. 27 f51a m3
FEe. 13 (547m3 I
JAN. 27 (534 ml
350
300
V)
a:
w
250
~
?OO
....
w
....
z
w
u
~
WASSAW BEACH
PROFILE 6
I
~
......
150
100
50
0
0
10
20
30
40
50
60
70
80
90
100
110
METERS
120
130
140
150
160
170
180
190
200
42
PROFILE VOLUMES
B-13
~
- · ~-----~
80~
o~~~---~~~--~~~---------~~-------------------------------------------------------
40
-4oV
-80
280
240
200
160
120
80
,en
c
1&.1
t-
1&.1
2
40
0
-40
-80
-120
-160
200
160
120
80
40
0
-40
-80
-120
80
40
0
-40
-80
_:~
~~pV~~~pV
SECTION
:~
8
6
4
43
VOLUMES
B-14
---
--
2
1'()0
18
16
14
12
10
8
6
4
2
J(
I'()
en
0:
w
tw
~
12
10
8
6
4
2
6
4
v
44
APPENDIX C
MODIFIED STAFF AND HORIZON TECHNIQUE FOR PROFILING
45
Graduate Staff
Hand Level
-- _
I.Sm
......
2m
...........................
. ........ ...
Bench
Mark tv:.; A
8
EQUIPMENT:
Hand Level
1.5m staff for hand level, with 2m light weight chain with
loop on the end.
2.5m staff graduated in lcm intervals, with zero located at
1. 5m from bass .
FIELD PROCEDURE:
Profiling is done norma l to the trend of the beach.
The elevation of the sand surface with reference to a stable
marker (i.e., sea wall, ·bench mark, curb, etc . ) is measured with the
graduated staff.
The hand level staff (A) is set up on that sand sur-
face with the hand level viewing offshore.
The graduated staff is
moved seaward until the 2m chain is taut and level.
The graduated
staff is held directly upright and viewed with the hand level.
When
the center line on the hand level is super-imposed on the horizon,
the the number on the graduated staff is recorded.
If the horizon
is poor, then the bubble in the hand level can be used for leveling.
46
Positive readings are located below the zero point and negative
number above.
After the number is recorded the hand level staff
is moved forward to the position of the graduated staff and the
procedure is repeated.
We have found that a small tape recorder
is two to three times more rapid than the pencil and paper recording
method.
GRAPHIC PROCEDURE:
Plotting the data is done by establishing the marker on graph
paper and plotting the sand surface from the initial measurement from
the graduated staff.
Each successive point is measured from the prior
point and not the original marker.
Acknowledgement: This three-part study was supported partially with
funds from the National Sea Grant Program (U, S. Department of Commerce,
Grant Number 04-5-158-4).