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Perdido Key beach nourishment project: Gulf Islands National Seashore 1992 annual report

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Title:
Perdido Key beach nourishment project: Gulf Islands National Seashore 1992 annual report
Series Title:
UFL/COEL (University of Florida. Coastal and Oceanographic Engineering Laboratory) ; 93/0005
Creator:
Otay, Emre N.
Place of Publication:
Gainesville, FL
Publisher:
Coastal and Oceanographic Engineering Department, University of Florida
Publication Date:

Subjects

Subjects / Keywords:
Perdido Key (Fla.)
Beach nourishment

Notes

Funding:
This publication is being made available as part of the report series written by the faculty, staff, and students of the Coastal and Oceanographic Program of the Department of Civil and Coastal Engineering.

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Source Institution:
University of Florida
Holding Location:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.

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UFL/COEL-93/005

PERDIDO KEY BEACH NOURISHMENT PROJECT: GULF ISLANDS NATIONAL SEASHORE
1992 Annual Report
by
Emre N. Otay and
Robert G. Dean
September, 1993
Sponsor:
Department of the Navy Southern Division Naval Facilities Engineering Command Charleston, SC 29411-0068




REPORT DOCUMENTATION PAGE
I. Report Pa. .3. Recipient's Acc8Aais No.
4. Title sad Subtitle 5. Report Data PERDIDO KEY BEACH NOURISHMENT PROJECT: GULF ISLANDS September, 1993
NATIONAL SEASHORE
1992 Annual Report
7. Autbor(.) 9. Partorang organization Report mo. Emre N. Otay and Robert G. Dean UFL/COEL-93/005
9. prtorming Organizatioa Name and Adress 10. Project/Task/ork Unit No. Coastal and Oceanographic Engineering Department University of Florida 1 C o 336 Weil Hall N62467-89-C-0500 Gainesville, FL 32611 1. Type of Report 12. Sponsoring Organization Mane and Address
Department of the Navy Annual Report Southern Division
Naval Facilities Engineering Command Charleston, SC 29411-0068 14.
15. Supplementary Notes
16. Abstract
This report is the third annual report in a continuing series documenting a field project
within the Gulf Islands National Seashore at Perdido Key, Florida. The field project includes the monitoring of a number of physical parameters related to the evolution of the Perdido Key beach nourishment project. Approximately 4.1 million m3 of dredge spoil from Pensacola Pass were placed upon approximately 7 km of the Gulf of Mexico beaches and 3 million m3 offshore
of Perdido Key between November, 1989, and October, 1991.
Beach profile data describing the evolution of the nourished beach are included, as well
as wave, current, tide, wind, temperature, and rainfall data to describe the forces influencing the evolution. Data describing the sediment sizes throughout the project area are also included.
A brief discussion of the data is included with an emphasis on evolution of the beach and
offshore nourishment.
17. Originator'& Kay words 18. Availability Statsaent
Beach nourishment
Sediment transport
Shoreline response
19. U. S. security CLassil. of moe Report 20. ti. S. Security Clasailf. of Thia Page 21. No. of Pages 2z. Price
Unclassified Unclassified 238




UFL/COEL-93-005

PERDIDO KEY BEACH NOURISHMENT PROJECT:
GULF ISLANDS NATIONAL SEASHORE
1992 Annual Report
Submitted to:
Department of the Navy
Southern Division
Naval Facilities Engineering Command
Charleston, SC 29411-0068
Prepared by: Emre N. Otay Robert G. Dean
Coastal and Oceanographic Engineering Department University of Florida Gainesville, FL 32611

September, 1993




TABLE OF CONTENTS
LIST OF FIGURES iv LIST OF TABLES vi
1 INTRODUCTION 1
2 DATA COLLECTION 1 2.1 Hydrographic and Topographic Surveys ...................................................... 6
2.2 Wave/Current/Tide Data ............................................................................. 6
2.3 Sand Samples ................................................................................................. 7
2.4 W eather Data ................................................................................................. 8
2.5 Photographic Documentation ...................................................................... 8
3 ISSUES CURRENTLY UNDER INVESTIGATION 8 3.1 Nearshore Berm Evolution .......................................................................... 9
3.2 Wave Data Comparison ................................................................................ 14
3.3 Washover Deposits Due to Hurricane Andrew ............................................ 17
4 DISCUSSION 17 4.1 Concentration of Fines .................................................................................. 17
4.2 Sediment Characteristics ........................................................................... 21
4.3 Profile Equilibration and Cross- Shore Sediment Transport ..................... 21

11




5 REFERENCES

APPENDIX I: BEACH and OFFSHORE PROFILES APPENDIX II: WAVE, CURRENT, and TIDE DATA January, 1992 December, 1992 APPENDIX III: GRAIN SIZE DISTRIBUTIONS APPENDIX IV: METEOROLOGICAL DATA January, 1992 December, 1992

iii

I-1
II-i III-1 IV-1

32




LIST OF FIGURES

FIGURE PAGE
1 Site location chart ........................................................................... 2
2 Components of beach nourishment monitoring project ................... 3
3 Cross-section of the profile nourishment at R-50 ........................... 10
4 Cross-section of the profile nourishment at R-58 ........................... 11
5 Three-dimensional view of the profile nourished area as measured
in O ctober, 1992 ............................................................................. 12
6 Contour map of the profile nourished area as measured in October,
1992 .............................................................................................. 13
7 Representative wave period (Tm), significant wave height (11 ) and
tidal stage recorded at Ranger Station during Hurricane Andrew .... 15
8 Representative wave period (Tm ), significant wave height (H, ) and
tidal stage recorded at Caucus Shoal during Hurricane Andrew ...... 16
9 Profiles at R-54 before and after Hurricane Andrew, showing
shoreline recession and overwash ................................................... 18
10 Percentage of fines for 5 m samples for all years of study............... 19
11 Percentage of fines for 8 m samples for all years of study............... 20
12a,b Longshore distribution of D50 for October, 1992 (solid line) with
envelope (dashed line) of sizes for 1989, 1990, 1991 and 1992 ...... 22,23

iv




FIGURE PAGE 13 Cross-shore distribution of D50. Temporal variation for all years of
study .............................................................................................. 24
14 Evolution of dry beach width since completion of beach
nourishm ent .......................................................................................... 25
15 Movement of -4 m contour since completion of beach nourishment 26 16 Average of profiles within nourished area. Averages based on
profiles at R-45, R-46, R-48, R-50, R-52, R-54, R-56 and R-58 ..... 28
17 Average of profiles west of nourished area. Averages based on
profiles at R-30, R-32, R-34, R-36 and R-38 .................................. 29
18 Cross-shore sediment transport within nourished area .................... 30
19 Cross-shore sediment transport west of nourished area ................... 31

v




LIST OF TABLES

PAGE

Chronology of Perdido Key field efforts .....................................
Chronology of Perdido Key field efforts (cont'd)........................

vi

TABLE
1 1

4
5




DRAFT
PERDIDO KEY BEACH NOURISHMENT PROJECT: GULF ISLANDS NATIONAL SEASHORE 1992 ANNUAL REPORT
1 INTRODUCTION
This report is one in a series of annual summaries of a continuing field project within Gulf Islands National Seashore at Perdido Key, Florida (Figure 1). Between November 1989 and September 1990 approximately 4.1 million m3 of dredge material were placed along the eastern 7 km of the Gulf of Mexico shoreline of Perdido Key. From September 1990 to October 1991, an additional approximately 3 million m3 of material were placed as an underwater deposit between DNR Monuments R-48 and R-60, extending 3.8 km in the longshore direction and up to 700 m in the cross-shore direction (see Figure 2).
Earlier reports (Work et al. 1990a, 1990b, 1991a, 1991b, 1991c, 1992a) discussed the site and physical data collection methods in detail. The focus of this report will be the results of the field work and physical data collection for 1992. The data describe topographic and bathymetric changes of the area, waves, currents, tides, sediment sizes, winds, temperatures and rainfall.
2 DATA COLLECTION
The study area and the data collection sites are shown in Figure 2. Table 1 presents a chronological summary of the ongoing field efforts since commencement of the project. A discussion of the data collection and analysis methods can be found in previous reports; only a brief summary will be included here.

1




AE
eI
*0
Figure 1: Site location chart

2

1




METEOROLOGICAL

/

0
5
0
8J
0o 0p

ST ATIONTIDE GAGE
S-4- R- R-65
PPROXIMATE DIRECTIONAL NOURISHMENT r ESTERLY PARK WAVE GAGE APPROXIMATE LIMTS OF 2ND DIRECTIONAL
PROFILE NOURISHMENT WAVEGAGE NOTE:
R-40 IS FLORIDA DEPARTMENT OF NATURAL RESOURCES MONUMENTED "RANGE 40"

A
m

0 1 2 3 4 5km




Table 1: Chronology of Perdido Key field efforts

Date 10/28-11/1/89
11/17/89 1/18/90 1/29/90 1/30/90
3/7-3/9/90 5/2/99
6/24/90 8/8/90 8/17/90 9/22-9/26/90
12/6/90 1/29-2/3/91 5/15-5/16/91 5/28-6/1/91 6/18-6/19/91 7/29-7/30/91 9/10/91 9/28-10/2/91
10/12-10/20/91

Task
Pre-nourishment survey: Wading/swimming profiles (Gulf and Bay) Offshore bathymetry Sand samples, photos Placement of nourishment material begins Wave gage tripod and standalone gage installed Tide gage with small stilling well installed at Ft. Pickens Pier, Santa Rosa Island Mechanical (analog) weather station installed Large stilling well installed for Ft. Pickens tide gage 56 sand samples collected, to replace those destroyed or not collected during pre-nourishment survey Standalone wave data collection package replaced with new package Digital weather station installed Standalone wave data collection package replaced with new package Placement of nourishment material completed First post-nourishment survey: Wading/swimming profiles (Gulf side) Offshore bathymetry Sand samples, photos Standalone wave data collection package replaced with new package Ft. Pickens pier tide gage re-surveyed Wading/swimming profile survey (Gulf side) Sand samples
Wave gage cable re-buried Wading/swimming profile survey (Gulf side) Sand samples
Shore-connected wave gage removed; cable cut Standalone wave gage installed Wind vane and anemometer replaced Standalone wave gage removed Fresh standalone wave gage installed Wading/swimming profile survey (Gulf side) Sand samples, photos Reattached Ft. Pickens pier tide gage yearly survey:
Wading/swimming profiles (Gulf side) Offshore bathymetry Installed heavyweight data/power cable for wave gage Replaced standalone wave gage near Ranger Station Installed shore-connected wave gage near Ranger Station Sand samples, photos

4

1




Table 1: Chronology of Perdido Key field efforts (cont'd) Date Task

10/23-10/24/91 1/16-1/22/92
4/15-4/16/92 7/8/92
10/17-10/20/92
10/27-10/29/92 1/22-1/25/93 5/14-5/18/93

Replaced shore-connected wave gage near Ranger Station Wading/swimming profiles (Gulf side) Replaced wind vane/anemometer Replaced shore-connected wave gage near Ranger Station Replaced standalone wave gage near Ranger Station Replaced shore-connected wave gage near Ranger Station Removed standalone wave gage from Ranger Station Installed new standalone wave gage near Caucus Shoal Replaced shore-connected wave gage near Ranger Station Replaced standalone wave gage near Caucus Shoal yearly survey:
Wading/swimming profiles (Gulf side) Replaced shore-connected wave gage near Ranger Station Replaced standalone wave gage near Caucus Shoal Sand samples, photos
Replaced weather station
bathymetric survey of range lines (Gulf side) bathymetric survey of "Profile Nourishment" Wading/swimming profiles (Gulf side) Cleaned shore-connected wave gage near Ranger Station Replaced standalone wave gage near Caucus Shoal Reset weather station
Wading/swimming profiles (Gulf side) Bathymetric survey of 8 lines along "Profile Nourishment" Bathymetric survey of "Profile Nourishment" Wading/swimming surveys of beach cusps Cleaned shore-connected wave gage near Ranger Station Replaced standalone wave gage near Caucus Shoal Reset weather station

5




2.1 Hydrographic and Topographic Surveys

The survey equipment and methodology used were unchanged from previous surveys. The beach profiles were surveyed to approximate depths of 4 to 5 m employing standard rod-and-level techniques, by first wading and then swimming over the deeper portions of the profiles. The offshore profile was surveyed by a boat equipped with a fathometer to measure depths and a microwave rangefinder system to measure horizontal distances. The profile lines were surveyed using the same azimuth values as in the previous surveys.
During the annual survey in October, 1992 twenty-five profiles were surveyed by boat, and an additional eight have been surveyed to wading/swimming depth (generally 4-5 m) only, in order to improve spatial resolution of the evolution of the beach nourishment. A total of eleven surveys have been conducted to date: the annual bathymetric surveys of 11/89, 9/90, 10/91 and 10/92 and the additional wading/swimming surveys of 1/91, 5/91, 9/91, 1/92, 6/92, 1/93 and 5/93. Data from the four annual surveys are presented in Appendix I.
2.2 Wave/Current/Tide Data
Waves, currents and tides are measured at two stations, one located offshore from the Ranger Station near DNR Monument R-34, and the other on Caucus Shoal near R-62. Both stations comprise P-U-V type electronic gages mounted on tetrapod shaped steel frames placed on the ocean floor. The P-U-V gages consist of two electronic sensors; a pressure transducer and a electromagnetic current meter. Raw data include a pressure signal and two velocity signals measured on a horizontal plane perpendicular to each other. All signals are collected once every 6 hours at 1 Hz sampling frequency for a 17 minute duration.
The gage near the Ranger Station is connected by a cable to a shore station which serves as a link for the remote control operation. The P-U-V data from this gage can be retrieved from

6




the University of Florida via telephone. The gage near Caucus Shoal carries a self contained storage device which can store data until divers retrieve the package every 3-4 months. Additional information about wave packages can be found in previous reports by Work et al., 1990 and 1991.
The P-U-V data are analyzed using directional spectrum methods to obtain wave height, wave period, wave direction, tide, current velocity and current direction. The computed wave, current and tide parameters are presented in Appendix II for the period of January to December 1992. There are seven plots per month for each gage. The first four plots present wave related parameters. These are: Wave period, significant wave height, modal wave direction and the spreading parameters of the wave spectrum. Wave information is followed by current and tide variables presented in three plots which show the current velocity, mean current direction and the tidal elevation.
2.3 Sand Samples
Sand samples are collected at eight locations along the profiles: Dune, mid-beach, berm, beachface, -1 m, -2 m, -5 m and -8 m. Details about the sampling locations and methodology can be found in the previous reports by Work et al., 1990 and 1991.
Grain size distributions have been determined by mechanical sieve analysis of each sample, using a series of twelve U.S. standard sieves with mesh numbers 10, 20, 30, 40, 50, 60, 70, 80, 100, 120, 140, 160. The analysis results are presented in Appendix III. Each figure shows grain size distributions at a particular location for different sample years. Several characteristic parameters of the grain size statistics have been analyzed, such as D50, mean diameter, sorting index, skewness and kurtosis. In this report only results related to D,, are presented. Other parameters can be obtained from the authors. A further discussion on sediment characteristics and spatial/temporal variations in grain sizes can be found in Chapter 4.

7




2.4 Weather Data
The electronic weather station was installed in June 1990 and collected data until May 1992. In October 1992 it was replaced with a similar unit. This new station operates with a locally installed data acquisition unit and a storage device. The weather station can be controlled remotely from the University of Florida and the stored data can be retrieved via telephone. The data acquisition unit consists of electronic sensors to measure wind velocity, wind direction, air temperature and rainfall. Data are sampled at 1 Hz frequency and the hourly mean, minimum and maximum values are saved in the storage device. Approximately once a week an operator calls the weather station from the University of Florida and retrieves the stored data into a computer. Appendix IV presents the analyzed data in biweekly time series of wind velocity, wind direction, air temperature and rainfall.
2.5 Photographic Documentation
Oblique color ground photography has been taken throughout the study to document changes as the nourished beach evolves. Photography is conducted in conjunction with each survey. Three photos are generally taken along each profile, viewing to the left along the beach, perpendicular to the beach and to the right along the beach. The reader may contact the authors regarding availability of the photographs.
3 ISSUES CURRENTLY UNDER INVESTIGATION
In addition to the information presented in the preceding sections of this report, three problems are under active study and are discussed here only briefly.

8




3.1 Nearshore Berm Evolution
As noted, following the beach nourishment, approximately 3 million cubic meters of sand were placed underwater in the area shown in Figure 2. Figures 3 and 4 show cross-sections through the entire profiles including the profile nourishment area for DNR Monuments R-50 and R-58. This portion of the nourishment is referred to as "profile nourishment" as distinguished from the "beach" nourishment which advanced the dry beach and its underwater extension. The profile nourishment sand was placed by bottom-dump barges such that each placement results in a more or less identifiable mound with the entire placement appearing as a very "hummocky" terrain (see Figure 5). Although the original program did not call for study of this portion of the nourishment, the program scope was modified in Spring, 1992 to include this element. Starting with the Fall survey of 1992, our annual surveys have encompassed the profile nourishment area. These efforts have included an extension of the profile lines in the area of profile nourishment and additional surveys "blanketing" the area. The results from the bathymetric survey in October, 1992 are presented in Figures 5 and 6 which show a three-dimensional view and a contour map of the nourished area.
The major issues concerning the profile nourishment center around the movement of the sand ashore with special emphasis on the rate. The rationale for hypothesizing landward movement is that if the profile was initially in equilibrium and "active", placement of additional material such as occurred here will result in a profile with an "excess of sand" leading to onshore sediment transport. Methods currently being employed to address this question include a focus on the landward edge of the placed material and the bathymetric evolution with particular emphasis on smoothing of the surface features. Perdido Key was impacted by Hurricane Andrew in October 1992 with peak significant waves at the two gages measured at 2.7 m. Based upon analysis of the profile nourishment data, it appears that there may be a small net landward

9

1




4
2

0
-2
-4
-6
-8

Perdido Key: Range 50 Azimuth 165 degrees
I I
NoV.89 Sep.90 Oct.91 ----Oct.92
'I'
-i
-o

0 200 400 600 800 1000 1200 1400 1600 Distance from Monument [m]
Figure 3: Cross-section of the profile nourishment at R-50.
10

L
0
$ .




Perdido Key: Range 58 Azimuth 165 degrees
Nov.89 Sep.90 Oct.91 -- ~ Oct.92
0 200 400 600 800 1000 1200 1400 1600

Distance from Monument [m] Figure 4: Cross-section of the profile nourishment at R-58.

11

4
2

L
0
.4~I
a,

0
-2
-4
-6




Perd Wdo Key Nearshore Nour Ishmen L Fi 5:Tre-ime e
Figure 5: Three-dimensional view of the profile nourished area as measured in October, 1992.

12




Perdido Key Nearshore Nourishment
400 600 800 1000 1200 1400 1600 5000 5000
--6.0
4500 5 4500 4000 0 4000 3500 3500
E 3000 - 3000
C
Q2500 7.0 2500
0
2000 2000 ~-)--7.0
1000 --. 1000 500 500
0 0 400 600 800 1000 1200 1400 1600 Cross-Shore Distance m
Figure 6: Contour map of the profile nourished area as measured in October, 1992.

13




movement of the underwater berm forming the profile nourishment; however, most of the evolution is apparent as a "spreading out" of the placed material. This is evident in Figures 3 and
4 for Monuments R-50 and R-58.
In addition to continuing to monitor the profile placement geometry, future efforts will be directed to the development of methodology for the prediction of the evolution of the underwater mound, including the rate of landward migration and the smoothing of the surface features.
3.2 Wave Data Comparison
As discussed previously, a second wave gage was installed in the vicinity of Caucus Shoals in April, 1992. One purpose of this gage was to identify and document any localized effects of the Entrance to Pensacola Bay, including the effects of Caucus Shoals. It is expected that causes of different wave properties at the two sites could include both wave refraction and wave diffraction, each of which can modify the wave height and wave direction. The effects of these processes are important as they can cause localized changes in the longshore sediment transport over the length of the nourishment project. These wave transformation phenomena are complicated due to the fact that they are functions of the incident wave direction and wave period. Also wave gages have a tendency to malfunction. The pressure sensor which provides the basis for determining wave heights is the most reliable element of the gage and the current meter which provides the basis for establishing wave direction is the least reliable.
At present, efforts are underway to identify portions of the wave records which are well-suited for identifying the wave transformation effects. Figures 7 and 8 present the wave characteristics at the two gages during the passage of Hurricane Andrew where it can be seen that the wave heights were approximately the same, at least until the Caucus Shoals gage ceased to

14




PERDIDO KET: RANGER STATION

20 15 T" 10 (SEC)
5 0 4 3

Hs
(M)

2

0
2

TiDE
(M)

0

-1

5 10 15 20 25 30 1 5 10 15 20 25 30

5

10

15

20

25

30

AUG. ,1992
Figure 7: Representative wave period (Tm), significant wave height (H) and tidal stage recorded at Ranger Station during Hurricane Andrew.

15

I I I I I I I I I I I I I I I I I I I I I I I I I I I I

I




PEROIDO KEY: CAUCUS SHOAL

20 15 T" 10 (SEC)
5 0

4
3
2
1
0
2
1
0

-1
-2

1 5 10 15 20 25 30 1 5 10 15 20 25 30

5

10

15
AUG. .1992

20

25

30

Figure 8: Representative wave period (Tm), significant wave height (H, and tidal-stage recorded at Caucus Shoal during Hurricane Andrew.

16

Hs
(M)

Ti m
(H)



1 i i i i i i i i i i i i i i i i i i i i i i i i i i i i i

I




function near the period of highest waves at about noon on August 24, 1992. During this period, the wave direction was not well established at either gage.
3.3 Washover Deposits Due to Hurricane Andrew
Hurricane Andrew caused washover deposits along portions of Perdido Key. These deposits can be characterized as extending approximately 25 m inland from the seaward limit of the berm and with a thickness of approximately 50 cm. Figure 9 presents an example of a cross-section (R-54) through the profile showing the washover deposit This deposit of sand has had the intended purpose of allowing the beach berm to build up naturally rather than to prevent overwash as would occur if the constructed berm were high as was the case for the 1985 beach nourishment. A very strong recovery "ridge" is also present in Figure 9. A manuscript is being developed for journal publication consideration describing this washover event and evaluating various methods for predicting the washover process and magnitudes.
4 DISCUSSION
Several features of the monitoring program, based on data collected last year merit discussion as presented below.
4.1 Concentration of Fines
The concentration of fines, located primarily between Ranges R-42 and R-59, are shown in Figures 10 and 11 respectively for the 5 and 8 m contours, and appear to be decreasing with time. The origin of these fines is the Pleistocene mud deposits that were excavated in the dredging operation. The decrease of fines with time is to be expected due to suspension during energetic wave events which causes suspension of the fines and distribution over wide areas.

17




2.5

0.5

Perdido Key Profiles

...1 L

0

-0.5

180

190 200 210 220 230 240
Distance from Monument

250
[m]

260 270

Figure 9: Profiles at R-54 before and after Hurricane Andrew, showing shoreline recession and overwash.

18

0

r54-9206 ---r54-9210 -

--

280


-

2




5 m Sand Samples

Percentage Finer than 0.0097 mm
* I ** I ii
nI

35 40 45 50 55 60 65

Range Number
Figure 10: Percentage of fines for 5 m samples for all years of study.

19

F

100 90 80 70

-Nov.'89
--- Sep.'90
Oct.'91 Oct.'92
-4

L..
C
IL
C-

60 50
40 30

2010
0
30

I




8 m Sand Samples
Percentage Finer than 0.0097 mm

. . . . ...... No...9
-Nov.'89
--------- - -- Sep.'90
----- Oct.'91
Oct.'92

i I i-

30 35 40 45 50
Range Number

55 60 65 70

Figure 11: Percentage of fines for 8 m samples for all years of study.

20

100

80 1-

60 k-

0 0) 0I

401-

20 1-

21

1




However the interpretation of the suspension and transport of fines must be tempered with the understanding that the distribution can be somewhat "spotty" due to local depressions and thus the data must be interpreted in the "aggregate" sense rather than on the basis of individual samples.
4.2 Sediment Characteristics
Sediment characteristics are summarized in Figure 12a for the dune, mid-beach, berm and beach face locations and in Figure 12b for the Im, 2m, 5m and 8m depths. The solid line in each of these figures represents the October, 1992 median diameters and the dotted lines represent the envelope of the size distributions measured including pre-nourishment. It is seen that in general the 1992 sizes are nearer the lower limit of the envelope than the upper limit. This is also shown in Figure 13 which shows the temporal variation of the longshore averaged median values. There is a discernible but slight trend toward the smaller sizes. The reason for this is not known as many times it is found that new deposits will experience "natural armoring" in which the finer sand will be removed by wind or water action leaving the less erodible coarser material. It is possible that Hurricane Andrew contributed to this effect. The two planned future sediment collections and analysis efforts may provide a basis for further interpretation and understanding.
4.3 Profile Equilibration and Cross-Shore Sediment Transport
The profiles in the nourishment project were placed steeper than those present prior to the nourishment project. Because the nourishment sediment is compatible to the native, it is expected that the final equilibrated profile will be very similar to the original. This equilibration is evident from Figures 14 and 15 which present respectively the alongshore changes in the dry beach width since November, 1989 and the alongshore change in the position of the 4 m contour

21




Mid Beach

40 50 Range Number

0.6
EO.4
E
0
"0.2

60

40 50 Range Number

Beach Face

0.6
E
0 LO3
C'0.2

40 50 Range Number

40 50 Range Number

Figure 12a: Longshore distribution of D50 for October, 1992 (solid line) with envelope (dashed lines) of sizes for 1989, 1990, 1991 and 1992.

22

0.6i

-0.4
E
0 I.')
00.2

30

>1'

. A

Berm

0.61

--.4
E
0
LO) 00.2

60

\ .

60

Dune

A | \ ^..

9' 1




-1m
..........

40 50 Range Number

-5m

40 50 Range Number

60

-2m

0.6i

. 4
0
E
LO
C

60

0

40 50 60 Range Number

-8m

0.6
E
0
LO C'0.2

40 50 Range Number

60

Figure 12b: Longshore distribution of D50 for October, 1992 (solid line) with envelope (dashed lines) of sizes for 1989, 1990, 1991 and 1992.

23

0.6
--.4
E
0 LO
00.2
0 31

- I ~ /\

0.6
-fO.4
E
0
LO 00.2

'N
. . . . . . . . .

0
30

- .. .. -...
IN /
I \'
'I

L
0




Crosshore Distribution of D50
Longshore averaged for All Years
0.6
E
(D 0.4
N
U)
(D 0.2E
Cl)
dune berm -1 m -5m
mid-beach beachface -2 m -8 m
*Nov.1989 ESep.1990 MOct.1991 [-]Oct.1992
Figure 13: Cross-shore distribution of D50 Temporal variation for all years of study.

24




Perdido Key Beach Nourishment
Planform Evolution

200

0
z
C
(D
C
C

1501

1001

501

0

- I *

30 35 40 45 50 55 60 65

Range Number

Figure 14: Evolution of dry beach width since completion of beach nourishment.

25

-- Sep.'90
--- Oct.'91
Oct.'92

I

, ,

,I

,I

,I

,I




Perdido Key Beach Nourishment
Movement of -4 m Contour

35 40 45 50 55 60 65

Range Number
Figure 15: Movement of -4 m contour since completion of beach nourishment.

26

100

50|

0

0)
00
0
z
C
E
U)
0
Cn

-50 -

4
I;
- /?
/
/

I I I I

--- Sep.'90

---- Oct.'91
Oct.'92

-100'
3c

I

I

I

I

i

I

I

0




since November, 1989. The post nourishment recession of the dry beach and advancement of the 4 m contour within the nourishment area are indications of a reduction in profile slope. This slope equilibration is also evident in Figure 16 which presents the average of eight profiles within the nourishment area. The upper portions of the profiles (down to an elevation of approximately -0.6 m) appear to have always had approximately the same slope as prior to nourishment. This could be due to very rapid adjustment before the first post-nourishment survey or could be due to the placement slope coinciding with the equilibrium slope. It is likely that both explanations are correct to some degree. Proceeding to greater depths, the offshore bar is not as well developed as for the pre-nourishment profiles. In fact the average profile one year after nourishment has only a small indication of a bar whereas after two years, the bar is now better developed. The slopes seaward of the bar are still substantially steeper than the pre-nourishment values. The features discussed above are consistent with the fact that the upper portions of the water column experience more wave energy and thus equilibrate more rapidly than the lower portions. Profile equilibration was hastened by the maximum 2.7 m peak significant wave heights (Figures 7 and 8) which occurred during Hurricane Andrew. However waves of this height had occurred previously at least twice during this study. It is generally believed, based on very limited data, that cross-shore equilibration requires approximately 2 to 5 years. Although the data collected in conjunction with this study seem reasonably consistent with this time frame, they provide more detail in particular the progressive evolution toward equilibrium with increasing water depth. Finally, it should be noted that these profile equilibration data provide the best documentation for any beach nourishment project to date. Figure 17 presents, for comparison the average of five profiles west of the nourishment.
An estimate of the average cross-shore sediment transport can be determined from sequential average profiles as presented in Figures 16 and 17. These calculated cross-shore transport rates which are presented in Figures 18 and 19 do not account for sand removed by

27

1




C
2
0
c-2
-z

Average Profiles Within Nourished Area Nov.89 -- Sep.90 Oct.91 --- -Oct.92
.
N -

-300

-200

-100 0 100
Distance from Sep.90 Waterline [m]

200

Figure 16: Average of profiles within nourished area. Averages based on profiles at R-45, R-46, R-48, R-50, R-52, R-54, R-56 and R-58.

28




Average Profiles West of Nourished Area
I I I II
Nov.89 --Sep.90 Oct.91 - Oct.92
- . ...

0 50 100 150 200 250
Distance from Sep.90 Waterline [m]

300 350 400

Figure 17: Average of profiles west of nourished area. Averages based on profiles at R-30, R-32, R-34, R-36 and R-38.

29

4
2
0
z
0
w
-4
-6

-50




Cross-shore Transport Rate within Nourished Area
0.20
--. Sep.'90 Oct.'91 0.15 -----. Sep.'90 Oct.'92
Oct.'91 Oct.'92
- 0.10
"E
0.05
I V
-200 -100 0 100 200 300 Distance from Sep.'90 Waterline [m]
Figure 18: Cross-shore sediment transport within nourished area, based on average profiles shown in Figure 16. Results based on profile deformations occurring between September, 1990 and October, 1992.

30




Cross-shore Transport Rate West of Nourished Area
I I I I *~-I

...... ---..
-- - Sep.'
Oct.'9 ......................---

0.10 0.08 0.06
0.04 0.02 0.00
-0.02
-0.04
-0.06
-0.08
-100

-1

400

Figure 19: Cross-shore sediment transport west of nourished area, based on average profiles shown in Figure 17. Results based on profile deformations occurring between September, 1990 and October, 1992.

31

0 100 200 300 Distance from Sep.'90 Waterline [m]

0 Oct.'91 0 Oct.'92 1 Oct.'92

-51,
CU
Ch

I




longshore transport. It is seen that within the nourished area (Figure 18), the maximum cross-shore transport during the second year after nourishment is approximately 60% to 70% of the value during the first year, even with the mobilizing activity of Hurricane Andrew during the second year. The approximate cross-shore sediment transport for the profiles west of the nourishment project is shown in Figure 19. Without discussing the details, the peak offshore transport magnitudes within the nourishment area are approximately 2.5 times greater than the transport magnitudes west of the nourishment area.
4 REFERENCES
Work, P.A., Lin, L.-H., and Dean, R.G., 1990a. "Perdido Key Beach Nourishment Project: Gulf
Islands National Seashore. Pre- Nourishment Survey, Conducted October 28 November
1989." Coastal and Oceanographic Engineering Department, University of Florida,
Gainesville, Florida. April 30, 1990. COEL 90/006.
Work, P.A., Lin, L.-H., and Dean, R.G., 1990b. "Perdido Key Beach Nourishment Project: Gulf
Islands National Seashore. First Progress Report." Coastal and Oceanographic
Engineering Department, University of Florida, Gainesville, Florida. August 27, 1990.
COEL 90/009.
Work, P.A., Lin, L.-H., and Dean, R.G., 1991a. "Perdido Key Beach Nourishment Project: Gulf
Islands National Seashore. First Post- Nourishment Survey Conducted September 22-26, 1990." Coastal and Oceanographic Engineering Department, University of
Florida, Gainesville, Florida. January, 1991. COEL 91/003.

32




Work, P.A., Lin, L.-H., and Dean, R.G., 1991b. "Perdido Key Beach Nourishment Project: Gulf
Islands National Seashore. 1990 Annual Report." Coastal and Oceanographic
Engineering Department, University of Florida, Gainesville, Florida. January, 1991.
COEL 91/004.
Work, P.A., Charles, L., and Dean, R.G., 1991c. "Perdido Key Beach Historical Summary and
Interpretation of Monitoring Programs.." Coastal and Oceanographic Engineering
Department, University of Florida, Gainesville, Florida. January, 1991. COEL 91/009.
Work, P.A., and Dean, R.G., 1992a. "Perdido Key Beach Nourishment Project: Gulf Islands
National Seashore. 1991 Annual Report." Coastal and Oceanographic Engineering Department, University of Florida, Gainesville, Florida. July, 1992. COEL 92/012.
Work, P.A., 1992b. "Sediment Transport Processes at a Nourished Beach." Ph.D. Dissertation,
Coastal and Oceanographic Engineering Department, University of Florida, Gainesville,
Florida. December, 1992. COEL TR/087.

33




I




APPENDIX I
BEACH and OFFSHORE PROFILES

Notes: 1) All elevations are in meters, relative to NGVD.
2) Horizontal origin is the survey monument, with distances toward
the Gulf of Mexico defined as positive.
3) Reported bearings are for observer standing on monument,
looking offshore along survey line.




Perdido Key: Range 30 Azimuth 170 degrees
Nov.89 ----4
Sep.90 Oct.91 2 Oct.92
0
0 -2
0)
-4
-6
0 200 400 600 800 1000 Distance from Monument [m]




- Azimuth 170 degrees

6- Nov.89 Sep.90 4 -Oct.91 Oct.92
2
0
0
-2
-4
-6
0 200 400 600 800 1000

Distance from Monument [m]

Perdido Key: Range 32




Perdido Key: Range 34 Azimuth 165 degrees
6-
Nov.89 4 Sep.90 Oct.91 Oct.92 2
0
0 ,
-4
-6
0 200 400 600 800 1000

Distance from Monument [m]




Perdido Key:

Range 36

- Azimuth 165 degrees

Nov.89 Sep.90 Oct.91 Oct.92

I"
1.
~ I'
x
t /\ ~ 5t St
"
"S

200

400

600

800

Distance from Monument

4
2

z
U

H U'

r.
0
CV4

0
-2
-4
-6

-200

0

[m]




Perdido Key: Range 38 Azimuth 160 degrees
4- Nov.89 Sep.90 Oct.91 Oct.92
0
0 -2
-4
-64
-200 0 200 400 600 800 1000

Distance from Monument

[m]




- Azimuth 160 degrees

Nov.89 --4 -
Sep.90 --Oct.91 2 Oct.92
0
0
- -2
-4
-6
-200 0 200 400 600 800 1000

Distance from Monument [m]

Perdido Key: Range. 40




-- Azimuth 160 degrees

4
Nov.89 Sep.90 2 -Oct.91 Oct.92
0
Z
-2
0
-4

0 200 400 600 800 1000

Distance from Monument [m]

Perdido Key: Range 42




Perdido Key: Range 43 Azimuth 160 degrees 4
Nov.89 Sep.90 2
Oct.91 Oct.92
0
0
4.)
-4
6 -S
-6 -l
-8-
0 200 400 600 800 1000

Distance from Monument [m]




Perdido Key: Range 44 Azimuth 160 degrees
4
Nov.89 Sep.90
2 -, Oct.91 ---Oct.92
0
-2
0
-4
-6
-8
-200 0 200 400 600 800 1000

Distance from Monument [m]




Perdido Key: Range 45 Azimuth 160 degrees
Nov.89 --2
Sep.90 Oct.91 ---Oct.92
.0
-4
r
4-j
-44
8
-200 0 200 400 600 800 1000

Distance from Monument [m]




Perdido Key: Range 46 Azimuth 165 degrees
6
Nov.89 Sep.90 Oct.91
2 Oct.92_0
-4
0
-6
-8
-10
0 500 1000 1500
Distance from Monument [m]




Perdido Key: Range 48 Azimuth 165 degrees
4 Nov.89 Sep.90 Oct.91 Oct.92
-2
0
-4
-6
0 500 1000 1500

Distance from Monument [m]




Perdido Key: Range 50 Azimuth 165 degrees
4 -Nov.89 Sep.90 Oct.91 --2
Oct.92
0

0

0) -4
-6
-8
0 200 400 600 800 1000 1200 1400 1600

Distance from Monument [m]




Perdido Key: Range 52 Azimuth 165 degrees 4- Nov.89 Sep.90
2 -Oct.91 Oct.92
0
-2
-4
-6
-8
0 500 1000 1500

Distance from Monument [m]




Perdido Key: Range 54 Azimuth 165 degrees
4
Nov.89 -Sep.90 2 Oct.91 Oct.92
0
-2
0
-4
-6
-8 - 6
0 200 400 600 800 1000 1200 1400 1600

Distance from Monument [m]




Perdido Key: Range 56 Azimuth 165 degrees
Nov.89 Sep.90
2-1
- r1 Oct.91 Oct.92
0
-2
0
Q) -4-6
0 200 400 600 800 1000 1200 1400 1600

Distance from Monument [m]




Perdido Key: Range 58 Azimuth 165 degrees
4 Nov.89
Sep.90
2- Oct.91 Oct.92
-4-
-6
0 200 400 600 800 1000 1200 1400 1600

Distance from Monument [m]




Perdido Key: Range 60 Azimuth 165 degrees Nov.89
2 Sep.90Yj Oct.91 Oct.92
0
-6
0 500 1000 1500

Distance from Monument [m]




Perdido Key: Range 61 Azimuth 165 degrees Nov.89 2- Sep.90 Oct.91 Oct.92
0
-2
-6
0 500 1000 1500

Distance from Monument [m]




Perdido Key: Range 62 Azimuth 165 degrees
4 Nov.89 Sep.90 Oct.91 2- Oct.92
r0
0
-4
0 200 400 600 800 1000

Distance from Monument [m]




Perdido Key: Range 63 Azimuth 165 degrees
4
Nov.89 3 Sep.90 Oct.91 2 Oct.92
1
0
-2
- 3 -....... ....
-4
0 200 400 600 800 1000

Distance from Monument

[m]




- Azimuth 170 degrees

3 Nov.89
Sep.90 -*Oct.91 Oct.92
1 II
0
0
-2
-3
-4
0 200 400 600 800 1000

Distance from Monument

Perdido Key: Range 64

[m]




- Azimuth 105 degrees

Nov.89 Sep.90
0 ---.--
Oct.92
-5
r,
0
-10 -.
-15
0 200 400 600 800 1000

Distance from Monument

Perdido Key: Range 65

[m]




Perdido Key: Range 66 Azimuth 105 degrees Nov.89 Sep.90
0
Oct.92
I -5
0
-10-
....... ...
-15
0 200 400 600 800 1000 Distance from Monument [m]




Perdido Key: Range 67

Nov.89 -Sep.90
0
Oct.91 Oct.92
-5
ir
-10
-15
-107
-20
0 200 400 600 800 1000
Distance from Monument [m]

- Azimuth 90 degrees







APPENDIX II

WAVE, CURRENT, and TIDE DATA from Offshore Gages located near Ranger Station and near Caucus Shoal January, 1992 December, 1992
+ Representative Wave Period
+ Significant Wave Height + Central Wave Direction
+ Spreading Parameters
+ Mean Current Velocity + Mean Current Direction
+ Tidal Stage
Notes: 1) Mean wave direction, G, is the direction that the wave is
heading. It is measured clockwise from magnetic north.
2) Mean current direction, 0., is the direction toward which the
current is heading. It is measured clockwise from magnetic
north.
3) Horizontal axis denotes day of month.

4) Tidal datum is mean sea level.




PERDIDO KEY: RANGER STATION
1 5 10 15 20 25 29

1 5 10 15 20 25 29

+ +

+ +

+

+

++ +

+
+ + ++

+++4++

+ + +
* -4-

-3-

[. + + ++
1 + 1- 1 t I I I I I I I I I
1 5 10 15 20 25 29

15

20

25 29

JAN. ,1992
Figure II-1: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, January, 1992.
11-2

20 15 TI 10 (SEC)
0
3

Hs
(M)

2

+ + +

0
N
E
S
H
120

+

S

90 60 30 -

0

1

5

S:+ S2:e
-0
+4
90w;I ekR II

10




1.

0.
Uc 0. (m/S)
0.

0.
0.

I.

9C
(DEG)

PERDIDO KEY: RANGER STATION
0
8
6
4
2 + nL .... I I
1 5 10 15 20 25 29

N
E

S
H
2

TiwE
(M)

-1
-2

-+ + + ++ +
-9
-9
+2
1 5 10 15 20 25 29

5

10

15

20

25 29

1

JRN. ,1992
Figure 1-1-2: Magnitude and Direction of Mean Current and Tidal Stage, January, 1992.
11-3

-




--I

PERDIDO KEY: RANGER STRTION

20 15 T" 10 (SEC)
5 0

1 5 10 15 20 25 29

3
2

1
0
w
N
E
S
120

1 5 10 15 20 25 29
V -r + + +-+

I i i i IIi I I i i i 1 5 10 15 20 25 29

90 60 30 1-

0

5

10

15

20

25 29

1

FEB. 1992
Figure 11-3: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, February, 1992.
IT-4

Hs
(M)

S

51:+ S2:~
+++
* e ++
0,41 ++4+ +%~'4t :+*++ 41*
1 14+ 1 "+ I"~ +




PERDIDO KEY: RANGER STATION

+I + 1 + IF I +* I -044+
1 5 10 15 20 25 29
+

+ +
++

+

+

+ + + +

+ +++ + + ~ + + +

I i I + I I 1 141 1 1 1 1 1 1 1 1 1 1 1 1 1+ 1 I ] 1 5 10 Is 20 25 29
I I I I I I I I I I I I I I I I I I f I I I I I I I I

10

15

20

25 29

5

FEB., 1992
Figure 11-4: Magnitude and Direction of Mean Current and Tidal Stage, February, 1992.
11-5

1.0

0. 8 k

Uc 0.6 (M/S)
0.4 I-

0.2 -

0.0
w
N

+
+
+

(DEG)

TiwE
(M)

E
S
2
1

-1
-2

I




PERDIDO KEY: RANGER STATION

20 15 T" 10 (SEC)
0

1 5 10 15 20 25 30

Hs
(M)

3
2

0
N
SE
S
w
120

S

90 60
30
0

1 5 10 15 20 25 30
-~
+ + -. 1 2 2 ++ + P4-+ -+14+
1 510 15 20 2S 30

5

10

15

20

25

30

MAR. 1992
Figure 11-5: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, March, 1992.
II-6

I I I II I I I I I I I I I I

* *SO:+ S2:*
0+ + + +
+
+*+ 0. +0 +> + +4F>N
+ 11 +41 4
1.~ddJ I + 1 1 10LN 1i- 1 b44 1 1 1+

I




PERDIDO KEY: RANGER STATION

0.8 I-

1 5 10 15 20 25 30

1 5 10 15 20 25 30

5

10

15

20

25

30

1

MAR. ,1992

Figure 11-6: Magnitude and Direction of Mean Current and Tidal Stage, March, 1992.
11-7

1.0

Uc 0.6
CM/SI
0.4 0.2 0.0
N

l+HtT H (4$f4.

+ + ++
+ ~ ++
-1 14 1 1

8c (DEG)

TiDE
(M)

E
s
w
2

1
0.

-1
-2

-

-

.




PERDIDO KET: RRNGER STATION

20 15 T" 10 (SEC)
5 0
4 3

Hs
(M)

2

0
w N
E
S
H 120
90 S 60
30 0

1 5 10 15 20 25 30

1 5 10 15 20 25 30
++ + + + + +
-+++
+ + + + + + ++
++ +++ + + 4+ + + ++ + ++ 44+ + ++
++H + + ++j- +
++
15 10 15 20 25 30
o S1:+ S2: '
+
0 ia

5

10

15

20

25

30

APR. ,1992
Figure 11-7: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, April, 1992.
11-8

I




PERDIDO KEY: RANGER STATION

1.0 0.8 Uc 0.6 (W/S)
0.4

0.2

0.0'

8c
(DEG)

w
N
E
H
2

TIDE
(H)

-1
-2

1 5 10 15 20 25 30
+ 0
+ + +
I I I i I I I I I I I I I I I I I I I I I I I I
1 5 10 15 20 25 30
-

5

10

15

20

25

30

APR. ,1992
Figure 11-8: Magnitude and Direction of Mean Current and Tidal Stage, April, 1992.
11-9

- 4 +

I

I




PERDIDO KEY: RANGER STATION

20 15 TN 10 (SEC)
5 0
3

Hs
(M)

2

I
0
w
N
E
S
w
120

9

S 6

3

1 5 10 15 20 25 30

1 5 10 15 20 25 30 + + + ++F -H + + 4 -+ +
+ +++ + + + + + +
+ + + +
I Ii1 14- 1 1 1 1 1 1+I i 1 ii 1 +1+ tI i I I I I I
5 10 15 20 25 30

0
0
0
0
o4 4e 0 o
- iit'hA-'lihi WI-~i 0 1 0 0-pa,0

1 5

10

15

20

25

MRY, 1992
Figure 11-9: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, May, 1992.
II-10

30




PERDIDO KEY: RANGER STATION

0.8 p

Uc 0.6L (M/S)

0.2

2
TEE
-1
-2

1 5 10 15 20 25 30
-+++
+ + + + +++
+ + + 0- + 2- + I I I I I I I III I I I I I I I I I I I I I I I I I I I I I
1 5 10 15 20 25 30

5

10

15

20

25

30

I

MAY, 1992

Figure II-10: Magnitude and Direction of Mean Current and Tidal Stage, May, 1992.
ITI-11

1.0

0.0,
H
N

4 +

8c
(DEG)

E
5
H

- I II I II I II




PERDIDO KEY: RANGER STATION

20
15 Tm 10 (SE C)
0

1 5 10 15 20 25 30

Hs
(M)

3
2
0

w
N
E
S
w
120

S

90 60
0
0

5 10 15 20 25 30
+ +++++ + +
+0- + + + + + +
+ + + + ++ + ++ + + + ++ + ++ + + + + + ++ 15 + 2+ 3
+ 41 ++ 4 +iI
I I I I I.I I I I I.&.. 1 .;- 1i i 44 1 111+ I1 I I I
5 10 15 20 25 30

5

10

15

20

25

30

JUN. ,1992
Figure II-l: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, June, 1992.
11-12

SO+ S2:o
00

-0
- o%

I




PERDIDO KEY: RANGER STATION

1 5 10 15 20 25 30

LI

w1

ec (DEG)

TiDE
(M)

N
E
S
H
2
1
0

-1
-2

1 5 10 15 20 25 30

5

10

15

20

30

JUN. ,1992

Figure 11-12: Magnitude and Direction of Mean Current and Tidal Stage, June, 1992.
11-13

1.0

0.8 -

Ue 0.6 -

(M/S)
0.4 0.2 0.0


- I I I I I I I I I I I I I I H I ~~~

SI III I I I I I I

- 4 H A 1" 1

I




PERDIDO KEY: RANGER STATION

1.
0 14
N
E
w
120

90 60 30
0

1 5 10 15 20 25 30

1 5 10 15 20 25 30
+ + ++ + + + +
+ + + + + + + +
+ + + ++ + + ++ ++++
+ + +
-4- ++ + + + +
++ + -b
15 10 15 20 25 30

5

10

15

20

25

30

JUL. ,1992
Figure 11-13: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, July, 1992.
11-14

20 15 T" 10 (SEC)
5 0
4 3

Hs
(M)

2

'It II 11 1 1 I I I I I I I

S

S:+ S2:*

I




PERDIDO KEY: RANGER STATION

1 5 10 15 20 25 30

-++ + +
S5 10 15 20 25 30

5

10

15

20

25

JUL. ,1992

Figure 11-14: Magnitude and Direction of Mean Current and Tidal Stage, July, 1992.
II-15

1.0

0.8 I-

Uc 0.6 r (m/S)
0.4 F-

0.2 -

0.0

Bc (DEG)

N
E
S
w

TiDE (M 0
-1
-2

I II I i i I I I I I I I I I I I I I I I I I I I II

I




PERDIDO KEY: RANGER STATION

20 15 Tm 10 (SEC)
5 0
4 3

Hs
(M)

2

1
0

N
E
5
w

120

9
6

3

1 5 10 15 20 25 30
1 5 10 15 20 25 30
++ + ++F
4- + + + + + + + 4 ++ +
+ ++++ ~+ + ++ + + + + +
+ + + + *,6
++ +++ + ++J + T *+
+ + + ++ ++ 4f' + +
+ + 4
+ + + + + + + + +
+ + + + +1
I 41 1 1j 1 1 1 1 A .1 1 1 1 1 1h I q I I . * 15 10 15 20 25 30

S,:+ S2:*
0
0
0 04 '

5

15

20

25

30

AUG. .1992
Figure 11-15: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, August, 1992.
11-16

S

I




PERDIDO KEY: RANGER STATION

1.0
0.8
Uc 0.6 (M/S)
0.4 0.2

U. U

H N
8c E
(DEG)
S
H
2

TiE
(m)

1
0

-1
-2

0 0 lt i i i i i i i I I I I I I

1 5 10 15 20 25 30
-++
-++
+ + 1 tHttt HH4H!ltVo Y
1 5 10 15 20 25 30

5

10

15

20

25

30

AUG. ,1992
Figure 11-16: Magnitude and Direction of Mean Current and Tidal Stage,
August, 1992.
11-17

- I II

I




PERDIDO KEY: RANGER STATION

1 5 10 15 20 25 30

1 5 10 is 20 25 30
+ ++
+ + + +
++ + 1+ + + + 20 2 + ++ + + ++
4* + + + +
+ 1I+ 1+44 1+I +I I I ~ + 1 .14 +4 + II 1is20 25 30

5

10

15

20

25

30

SEP., 1992
Figure 11-17: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, September, 1992.
11-18

20

'5 }-

T" 10 (SEC)
0
4 3

Hs
(M)

2

1
0
w
N
E
5
120

S

90 60 30

Si:+ S2:*
...
- f

1

01




PERDIDO KEY: RANGER STATION

1 5 10 15 20 25 30
15 to is 20 25 30

5

10

15

20

25

30

SEP., 1992

Figure 11-18: Magnitude and Direction of Mean Current and Tidal Stage, September, 1992.
II-19

1.0

0.8 -

Uc 0.6 r (M/S)
0.14 -

0.2 0.0

8c (DEG)

H
N
E
S
2

TIDE (WI

-1
-2

I I I I I I I I I I I I I I I I I I I

I
0

I




PERDIDO KEY: RANGER STATION

20 15 TM 10 (SEC)
5 0
4 3

Hs
(M)

2

I
0 w
N
E
S w
120 90 S 60

1 5 10 15 20 25 30

- I Ih I I ,~ I I I I I I I I I I

1 5 10 15 20 25 30
++ 1 +
- + ++ +++%
+ ++
+ + +
++ +4 + + +NH 1++ ++
I I I + I1 1+1+1 1 1 1 1 -H I I I I I I I I I + I I I I I
1 5 10 15 20 25 30 S:+ S2:*
F

30 k

0

5

10

15

20

25

30

OCT. ,1992
Figure 11-19: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, October, 1992.
11-20

I I I I I I I I

A t

+4

I




PERDIDO KEY: RANGER STATION

1.0 0.8 UC 0.6 (M/S)
0.4

0. 2 F

A A

V.

8c (DEG)

TiDE
(M)

N
E
s
2
1

-1
-2

5 10 15 20 25 30
++ + + +
+ +
44-+H44-4 +R-+H
I I II I I I I I I I I I I I I II I I I I I I I I
5 10 15 20 25 30

5

10

15

20

25

30

OCT. ,1992

Figure 11-20: Magnitude and Direction of Mean Current and Tidal Stage, October, 1992.
TT-21

.4. -P.--O++1++-- -4-- +++
4+4-444ii + ++ +
I~+ tf I I 1+ 1 1 1- 1+ 1+ 11++

i i a I I I I I I I I I I I I I I i t

I




PERDIDO KEY: RANGER STATION

20 15 TM 10
(SE C)
0
4 3

Hs
(M)

2

0
H
N
E
S
H
120

9
6

3

1 5 10 15 20 25 30

5 10 15 20 25 30
+++++++ + + ++ + 1 + -6,+ + ++ + ++ + ++
++ + + + + +
+ + + + + + + + ++ ++ + + + + + + + + + I 1 141 1 1 +1 1 1 [+ + t
5 10 15 20 25 30

SO+ S2:*
0
0
0 e''

1 5

10

is

20

25

30

NOV. 1992
Figure 11-21: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, November, 1992.
11-22

S




PERDIDO KEY: RANGER STATION

1.0 0.8 UC 0. 6
(M/S)
0.4 0.2.
0.0
w N
8C E (DEG)
S
w
2
1
Till~ (MI M 0
-1
-2

W-+4+-t+4+4+-H+-++4- +HW+H--+W++-+- ++++ 25 30H-H I + 1+1+1+1+ ++ +I + +1+ I I + I I 1+1 + 1 1+ 1+ 1+1+ 1+1
1 5 10 is 20 25 30

- ++ + 11 141 1 1 1 1 1 1+1+111,111111+1+1+1+1
1 5 10 15 20 25 30

5

10

15
NOV. ,1992

20

25

30

1

Figure 11-22: Magnitude and Direction of Mean Current and Tidal Stage, November 1992.
II-23

-




PEROIDO KEY: RANGER STATION

20
15 T" 10 (SEC)
0
4 3

1 5 10 15 20 25 30

5

10

15

20

25

DEC. ,1992
Figure 11-23: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, December, 1992.
11-24

1 5 10 15 20 25 30
ii I 15 20 25 30 1 5 10 15 20 25 30

-

Hs
(M)

2

0
H
N
E
S
H
120

+ +: + +++ ++ + + +
+44- + + +-+ ++ + + ++++
I I I I I + I I 4I I I I I I I I I I I I I I I I I I I I I

S

90 60 30 01

S1:+ S2:.
-I


-

I




PERDIDO KEY: RANGER STATION

1.0

0.68 -

Uc 0.6 (M/S)
0.4 -

0.21

0.0

H
N
E

S
H
2
1
0

-1
-2

1 5 10 15 20 25 30
-H- -4-+IH---Ii-* -44-H -+H-*4i-4-* + 44+ -* HH- +
+ + + + I + +
- +
I I I I I 1+4 1 I I I I I I I I I I I I I I
1 5 10 iS 20 25 30

5

10

15

20

25

DEC. ,1992

Figure 11-24: Magnitude and Direction of Mean Current and Tidal Stage, December, 1992.
11-25

4+ 4J*+H*HI.* -4 +.+ + 4h4j4 o-+ 0+ 1+-4H* 4 + + I+ I+141 + i I.I+ I+ I I f I+I+I+I I I I I +I+ I+ I+ ++I I I+

8c (DEG)

TiDE
(M)

- i I I I I I I

I




20 15 Tm 10
(SE C)
0

Hs IM)

3
2
1
0

N
SE
S
w
120 90 S 60
30

0

1

PERDIDO KET: CAUCUS SHORL
5 10 15 20 25 30
1 5 10 15 20 25 30 ~~++44+ +4t* +
+
1 5 10 15 20 25 30 S1:+ S2:e*
-%
-~
III 11111111111 4i iL$i A i 4.

5

10

15

20

30

APR, 1992
Figure 11-25: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, April, 1992.
11-26




PERDIDO KET: CAUCUS SHOL

0.8 -

5 10 15 20 25 30
- ++ +4H-+4+' + + 1+f
++ ++ + + +
- ++ I + -4 1 1 1 1 +1 i i i
5 10 15 20 25 30

5

10

15

20

25

30

1

RPR, 1992

Figure 11-26: Magnitude and Direction of Mean Current and Tidal Stage, April, 1992.
11-27

1.0

Uc 0.6 (M/S)
0.4

0.2

0.0
w
N

+ + + + +++ + ++ 1111111 1 I I I I I i--i40 I + t

8c
(DEG)

TimE
(H)

E
S
2
1

-1
-2

-

.




PERDIDO KET: CAUCUS SHOAL

1 5 10 15 20 25 30

1 5 10 15 20 25 30

1 5 10 15 20 25 30

60

10

15

20

25

5

30

MAY. ,1992
Figure II-27: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, May, 1992.
11-28

20 15 TH 10 (SEC)
S 0
4 3

Hs
(M)

2

I
0
H
N
E
S
w
120
90

+ + + + +
+ + + + +
i t i+ I 4 + 1 .I + II-

S

30
0

S I:+ S2:*
4' '
-4 i

I

I




PERDIDO KET: CAUCUS SHORL

+ + 4 +
-H* ++i +O+*+0 +
+pt + ++ + + -F~t*4+ ++ 4 .14+
- + -4+ + + +++ ++ +
1 1I I I 2+I 2+tA 3I
5 10 15 20 25 30
+ + + +
+O ++ + +F+++
5 10 15 20 25 30

10

15

20

25

30

1 5

MAY. ,1992

Figure 11-28: Magnitude and Direction of Mean Current and Tidal Stage, May, 1992.
TT-29

1.0 0.8

UC 0. 6-

(M/S)
0.4 0.2 0.0
w N

8c (DEG)

TIDE
CM)

E
2
1
0

-1
-2

i i i i i i i i i i i i i i i i i i i i i iii ii I I I




PERDIDO KEY: CAUCUS SHOAL

20 15 Tm 10 (SEC)
0 14
3

Hs
(M)

2

120 90

S

60

30
0

1 5 10 15 20 25 30
- -0+
+ + +
1 1 1 1 +I I I I I I I I I
5 10 15 20 25 30

5

10

15

20

25

30

JUN. ,1992
Figure 11-29: Representative Wave Period, Significant Wave Height, Central Direction and Spreading Parameters, June, 1992.
11-30

Si:+ S2:*
~++
- + L Vre ? ~ ~ t.&~

I

I




PERDIDO KEY: CAUCUS SHOAL

1.0 0.6

Ue 0.6 (M/S)
0.4

H- +-H.+ + +++4 + +
I I I 1 III1 4- I I +1 i

+ i+1 ** i i i + 04 + + +
1 1+1I- 11 1 11 11 11 1 1

1 5 10 15 20 25 30
+ + + + H- + + +
- + + +
+ +
- +
1 I I I I I I I I I I I 2 2 3 0I I I
1 5 10 15 20 25 30

5

10

15

20

25

30

JUN. ,1992
Figure 11-30: Magnitude and Direction of Mean Current and Tidal Stage, June, 1992.
11-31

0.2 0.0
w
N

8c (DEG)

TIDE
(MI

E
S

2
1
0

-1
-2

1