• TABLE OF CONTENTS
HIDE
 Front Cover
 Title Page
 Table of Contents
 Executive summary
 Main
 Workshop participants
 Workshop program
 Monitoring program of the Office...
 Sediment criteria for beach nourishment...
 Introduction of a "simple" method...
 A "white paper" on shoreline...
 Results of working group 1
 Results of working group 2
 Results of working group 3
 Manatee County Beach Nourishment...
 Martin County Beach Nourishment...
 Captiva Island Beach Nourishment...
 Longboat Key Beach Nourishment...
 Ocean Ridge Beach Nourishment...
 Key Biscayne Beach Nourishment...
 Juno Beach Nourishment Project
 St. Johns County Beach Nourishment...
 Report review comments of Ebersole...














Group Title: UFLCOEL-2001009
Title: Beach nourishment prediction methodology, monitoring and sediment characteristics report of CETAC workshop 2
CITATION THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00091079/00001
 Material Information
Title: Beach nourishment prediction methodology, monitoring and sediment characteristics report of CETAC workshop 2 results from a workshop on beach nourishment, monitoring and sediment characteristics held under the auspices of Office of Beaches and Coastal Systems, Department of Environmental Protection, State of Florida : workshop held in Atlantic Beach, FL, October 24 to 26, 2000
Series Title: UFLCOEL-2001009
Physical Description: 1 v. (various pagings) : ill. ; 28 cm. +
Language: English
Creator: Dean, Robert G ( Robert George ), 1930-
Coastal Engineering Technical Advisory Committee -- Workshop, 2000
Florida -- Office of Beaches and Coastal Systems
Publisher: Coastal & Oceanographic Engineering Program, University of Florida
Place of Publication: Gainesville Fla
Publication Date: 2001
 Subjects
Subject: Beach nourishment -- Congresses   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
bibliography   ( marcgt )
conference publication   ( marcgt )
non-fiction   ( marcgt )
 Notes
Bibliography: Includes bibliographical references (p. 20-21).
Statement of Responsibility: prepared by Robert G. Dean.
General Note: "May 23, 2001."
General Note: Disc contains 10 PowerPoint presentations.
 Record Information
Bibliographic ID: UF00091079
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 49575832

Table of Contents
    Front Cover
        Front Cover
    Title Page
        Page i
    Table of Contents
        Page ii
        Page iii
        Page iv
        Page v
        Page vi
    Executive summary
        Page 1
    Main
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
        Page 15
        Page 16
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
    Workshop participants
        Page A-1
        Page A-2
        Page A-3
        Page A-4
    Workshop program
        Page B-1
        Page B-2
        Page B-3
    Monitoring program of the Office of Beaches and Coastal Systems
        Page C-1
        Page C-2
    Sediment criteria for beach nourishment projects
        Page D-1
        Page D-2
    Introduction of a "simple" method for calculating beach nourishment project performance
        Page E-1
        Page E-2
        Page E-3
        Page E-4
        Page E-5
        Page E-6
        Page E-7
        Page E-8
        Page E-9
        Page E-10
        Page E-11
        Page E-12
        Page E-13
        Page E-14
        Page E-15
    A "white paper" on shoreline modeling
        Page F-1
        Page F-2
        Page F-3
        Page F-4
        Page F-5
        Page F-6
    Results of working group 1
        Page G-1
        Page G-2
        Page G-3
        Page G-4
    Results of working group 2
        Page H-1
        Page H-2
        Page H-3
        Page H-4
        Page H-5
        Page H-6
    Results of working group 3
        Page I-1
        Page I-2
        Page I-3
        Page I-4
    Manatee County Beach Nourishment Project
        Page J-1
        Page J-2
        Page J-3
        Page J-4
        Page J-5
        Page J-6
        Page J-7
        Page J-8
        Page J-9
        Page J-10
        Page J-11
        Page J-12
        Page J-13
    Martin County Beach Nourishment Project
        Page K-1
        Page K-2
        Page K-3
        Page K-4
        Page K-5
        Page K-6
        Page K-7
        Page K-8
        Page K-9
        Page K-10
        Page K-11
    Captiva Island Beach Nourishment Project
        Page L-1
        Page L-2
        Page L-3
        Page L-4
    Longboat Key Beach Nourishment Project
        Page M-1
        Page M-2
        Page M-3
        Page M-4
    Ocean Ridge Beach Nourishment Project
        Page N-1
        Page N-2
        Page N-3
        Page N-4
        Page N-5
        Page N-6
        Page N-7
        Page N-8
        Page N-9
        Page N-10
        Page N-11
        Page N-12
        Page N-13
        Page N-14
        Page N-15
        Page N-16
        Page N-17
        Page N-18
        Page N-19
    Key Biscayne Beach Nourishment Project
        Page O-1
        Page O-2
        Page O-3
        Page O-4
        Page O-5
        Page O-6
    Juno Beach Nourishment Project
        Page P-1
        Page P-2
        Page P-3
    St. Johns County Beach Nourishment Project
        Page Q-1
        Page Q-2
        Page Q-3
        Page Q-4
        Page Q-5
        Page Q-6
        Page Q-7
        Page Q-8
        Page Q-9
        Page Q-10
        Page Q-11
        Page Q-12
        Page Q-13
        Page Q-14
    Report review comments of Ebersole and Gravens of the U.S. Army Corps of Engineers
        Page R-1
        Page R-2
        Page R-3
        Page R-4
        Page R-5
        Page R-6
        Page R-7
        Page R-8
        Page R-9
        Page R-10
        Page R-11
        Page R-12
        Page R-13
        Page R-14
        Page R-15
Full Text



UFL/COEL -2001/009


BEACH NOURISHMENT PREDICTION METHODOLOGY,
MONITORING AND SEDIMENT CHARACTERISTICS
REPORT OF CETAC WORKSHOP 2





by



Robert G. Dean


May 23,2001



Results from a Workshop on Beach Nourishment,
Monitoring and Sediment Characteristics

Held Under the Auspices of:

Office of Beaches and Coastal Systems
Department of Environmental Protection
State of Florida

Workshop Held on October 24 to 26, 2000
Atlantic Beach, FL











BEACH NOURISHMENT PREDICTION METHODOLOGY,
MONITORING AND SEDIMENT CHARACTERISTICS
REPORT OF CETAC WORKSHOP 2



May 23, 2001





Results from a Workshop on Beach Nourishment,
Monitoring and Sediment Characteristics
Held Under the Auspices of:

Office of Beaches and Coastal Systems
Department of Environmental Protection
State of Florida

Workshop Held in

Atlantic Beach, FL
October 24 to 26, 2000










Prepared by:

Robert G. Dean
Department of Civil and Coastal Engineering
University of Florida
Gainesville, Florida 32611








TABLE OF CONTENTS

LIST OF FIGURES ....................................................... v

LIST OF TABLES ........................................................... vi

EXECUTIVE SUMMARY .................................................. 1

1.0 INTRODUCTION .................................................. 2

2.0 ORGANIZATION OF THIS REPORT................................... 2

3.0 COMPARISON OF METHODS FOR PREDICTING PERFORMANCE OF
BEACH NOURISHMENT PROJECTS .................................. 3
3.1 Introduction ................................................. 3
3.2 Approach .................................................. 3
3.3 Results for Individual Projects ...................................... 3
3.3.1 General ................. .................................3
3.3.2 Manatee County Project ....................................... 4
3.3.3 Martin County Project ....................................... 6
3.3.4 Captiva Island ............................................. 8
3.3.5 Longboat Key ............................................ 8
3.3.6 Ocean Ridge ............................................. 8
3.3.7 Key Biscayne ............................................. 13
3.3.8 Juno Beach ............................................... 15
3.3.9 St. Johns County ......................................... 16

4.0 QUANTITATIVE MEASURE OF PREDICTIVE SKILL .................... 16

5.0 RESULTS, FINDINGS AND RECOMMENDATIONS ...................... 18
5.1 Use of Models in Prediction of Beach Nourishment Performance ........... 18
5.1.1 GENESIS ................................................ 19
5.1.2 DNRBS ................................................. 19
5.2 Monitoring ................................................. 19
5.3 Rule Revision and Sand Specification ............................... 20

6.0 ACKNOWLEDGMENTS ..............................................20

7.0 REFERENCES .................................................. ... 20






ii








APPENDICES

A WORKSHOP PARTICIPANTS ....................................... A-1

B WORKSHOP PROGRAM ............................................ B-1

C MONITORING PROGRAM OF THE OFFICE OF BEACHES AND COASTAL
SYSTEMS ................... .......... ..... . ......... . .. C-1

D SEDIMENT CRITERIA FOR BEACH NOURISHMENT PROJECTS ........... D-1

E INTRODUCTION OF A "SIMPLE" METHOD FOR CALCULATING BEACH
NOURISHMENT PROJECT PERFORMANCE WITH EXAMPLES FOR DELRAY
BEACH, FL, MIDTOWN BEACH, FL AND MANATEE COUNTY, FL ......... E-1

F A "WHITE PAPER" ON SHORELINE MODELING ......................... F-l

G RESULTS OF WORKING GROUP 1: "Role of Modeling in Beach Nourishment
Design" ........................................................ G-1

H RESULTS OF WORKING GROUP 2: "Monitoring Issues" ................... H-1

I RESULTS OF WORKING GROUP 3: "Design Accuracy Assessment and
Calibration Methods" .................................................. I-1

J MATERIAL PROVIDED FOR CASE STUDY 1: MANATEE COUNTY BEACH
NOURISHMENT PROJECT ......................................... .... J-

K MATERIAL PROVIDED FOR CASE STUDY 2: MARTIN COUNTY BEACH
NOURISHMENT PROJECT.......................................... K-1

L MATERIAL PROVIDED FOR CASE STUDY 3: CAPTIVA ISLAND BEACH
NOURISHMENT PROJECT............................................ L-1

M MATERIAL PROVIDED FOR CASE STUDY 4: LONGBOAT KEY BEACH
NOURISHMENT PROJECT........................................... M-1

N MATERIAL PROVIDED FOR CASE STUDY 5: OCEAN RIDGE BEACH
NOURISHMENT PROJECT........................................... N-1

O MATERIAL PROVIDED FOR CASE STUDY 6: KEY BISCAYNE BEACH
NOURISHMENT PROJECT........................................... 0-1








P MATERIAL PROVIDED FOR CASE STUDY 7: JUNO BEACH NOURISHMENT
PROJECT ..................................................... ...... P-1

Q MATERIAL PROVIDED FOR CASE STUDY 8: ST. JOHNS COUNTY BEACH
NOURISHMENT PROJECT........................................... Q-1

R REVIEW COMMENTS BY EBERSOLE AND GRAVENS OF U. S. ARMY CORPS
OF ENGINEERS ................................................. R-l








LIST OF FIGURES


FIGURE PAGE

1 Measured and Predicted Volumetric Performance of the Manatee County Beach
Nourishment Project ........ ...... ......... ................... .......... 5

2 Measured and Predicted Longshore Distributions of Volume Density Remaining
After 4.8 Years. Manatee County Beach Nourishment Project ..................... 5

3 Proportional Volumes and Plan Areas Remaining Within Project Limits. Manatee
County Beach Nourishment Project....................................... 6

4 Measured and Predicted Volumes Remaining. Martin County Beach Nourishment
Project ..... ........................................................... 7

5 Comparison of Measured and Predicted Shoreline Changes. Martin County Beach
Nourishment Project .......... ......................... ................ 7

6 Comparison of Measured and GENESIS Predicted Volumes Remaining. Captiva
Beach Nourishment Project ...................................... ........ 9

7 Comparison of Measured and Predicted Percent Volume Remaining by DNRBS.
Longboat Key Beach Nourishment Project .... ........................... 10

8 Measured and Predicted Shoreline Changes. Mid-Key Longboat Key Beach
Nourishment Project ......... .. ... ..... .......... ...................... 10

9 Calibration Results of GENESIS With Historical Data. Ocean Ridge Beach
Nourishment Project .................................................... 11

10 Predictions With GENESIS. Ocean Ridge Beach Nourishment Project ............. 11

11 Flow Diagram for GENESIS Calibration Method. Ocean Ridge Beach Nourishment
Project ...... .... ................. ............ ........ ................ 12

12 Predictions Using DNRBS. Ocean Ridge Beach Nourishment Project ............. 12

13 Comparisons of One Year Monitoring Results With Predictions by GENESIS and
DNRBS ................. ................... .................... 13








14 Calibration Results Based on GENESIS and DNRBS. Key Biscayne Beach
Nourishment Project .................................................... 14

15 Measured and Predicted Shoreline Changes. Key Biscayne 1962-1987 ............. 14

16 Comparison of Measurements and Predictions Based on GENESIS and DNRBS for
1987 Key Biscayne Beach Nourishment Project ............................... 15

17 Predicted Performance of Juno Beach Project by GENESIS and DNRBS, 5 Years
After Project Construction ................................... ........... 16

18 Predictions of Volumetric Change After 10 Years for St. Johns County Project ...... 17


TABLES


TABLE PAGE

1 Projects Examined in the Workshop .................................. ...... 4

2 Summary of Normalized Standard Deviations for Projects Having Measured Data
and Two Model Predictions Available ..................................... 18







EXECUTIVE SUMMARY

The second CETAC workshop was held on October 24 26, 2000 to evaluate beach nourishment
design methodology, monitoring and acceptable sediment characteristics. The main results
developed during this workshop are presented below.

BEACH NOURISHMENT DESIGN METHODOLOGY

Two design methodologies were evaluated based on eight beach nourishment case studies: (1)
A method that simplifies the bathymetry and forcing, and (2) A method that utilizes the detailed
bathymetry and forcing. For purposes of discussion, the first method is termed the "simple"
method and the second the "detailed" method. Additionally, for the simple method, representative
wave forcing and other required design parameters have been developed for the sandy beach
segments of the State of Florida. The detailed method requires calibration and verification phases
which ideally apply concurrent wave information and measured volumetric (or less desirably,
shoreline) changes. The required time and effort to apply the simple method are considerably less
than for the detailed method.

For five of the eight beach nourishment case studies examined in this report, it was possible,
through comparison with monitoring results, to carry out nine quantitative comparisons of the
predictive capabilities of the two methods. It was found that in five of the comparisons, the
simple model provided substantially better agreement, in two of the comparisons, the simple
method provided marginally better results, in one of the comparisons, the two methods were of
equal skill and in one comparison, the detailed method provided marginally better results.
Possible reasons for the relative performance of the two models are discussed.

MONITORING

Guidelines for monitoring beach nourishment and other projects were discussed. It was agreed
that annual surveys of projects are justified. Other monitoring components were left more flexible
and should be tailored to the particular project under consideration.

GUIDELINES FOR ACCEPTABLE NOURISHMENT SEDIMENT

There was general agreement with the overall concept of similarity of sediment serving as a
guideline. However, it was noted that in some areas, available sources of sediment that could
meet this criterion may be limited and that caution is in order to ensure that limitations are not
set that could inappropriately jeopardize future nourishment projects. A committee was
established to develop specific sediment guidelines for further consideration by CETAC.

TOPICS FOR FUTURE CETAC WORKSHOPS

Possible topics for future workshops were discussed and identified as: (1) Environmental
considerations of beach nourishment, and (2) Performance predictions of a beach nourishment
project in advance of construction, monitoring and comparison of monitoring and predictions.







BEACH NOURISHMENT PREDICTION METHODOLOGY,
MONITORING AND SEDIMENT CHARACTERISTICS
REPORT OF CETAC WORKSHOP 2

1.0 INTRODUCTION

The Coastal Engineering Technical Advisory Committee (CETAC) was formed by the Office of
Beaches and Coastal Systems (OBCS) as a group of coastal engineering and geology professionals
and educators to evaluate and develop recommendations for some of the more immediate and
difficult issues facing the OBCS and the State of Florida in their roles as Stewards of Florida's
valuable beach resources. The approach to accomplishing these objectives has been through a series
of focused workshops in which individuals are requested to prepare materials and/or
recommendations in advance of the workshop and to make presentations for discussion/evaluation
by the workshop Participants. The second CETAC Workshop was held in Atlantic Beach, FL from
October 24 to 26, 2000 with 28 Participants representing a broad cross-section of the coastal
engineering and geology communities in attendance; this report summarizes the findings of this
second workshop. A roster of the Participants is presented as Appendix A and a Workshop Agenda
is presented as Appendix B.

As indicated in the Agenda (Appendix B), issues addressed at the second workshop included: (1)
Rule revision and sand specification, (2) Monitoring issues, and (3) Predictability of beach
nourishment performance. One-half day was dedicated to the two first issues and the remaining day
focused on predictability of beach nourishment performance. During the last one-half day of the
workshop, three working groups were formed to develop "position papers" on the following: (1)
Working Group 1: Numerical models in beach nourishment design, (2) Working Group 2:
Monitoring issues, and (3) Working Group 3: Design accuracy assessment and calibration methods.
The Working Group reports are presented as Appendices with only minor editorial and formatting
changes. Findings related to the focus of this workshop are summarized in the following sections of
this report. This report is organized with this main body of the report providing relatively brief
summaries of the deliberations and findings and with additional details provided in the 18
Appendices.

2.0 ORGANIZATION OF THIS REPORT

As noted, the focus of this second workshop was the comparison of the two methodologies that have
been employed in Florida for predicting the performance of beach nourishment projects. Thus the
organization of this report differs from the order in which the three issues noted above were
addressed during the workshop process. Section 3 of this report summarizes the results and presents
the findings related to two methodologies for predicting performance of beach nourishment projects.
Additional detail is presented in Appendix C which describes one of the models used in the
comparison, and Appendices G through S which contain material presented at the workshop and
through the copies of the individual Powerpoint presentations which are provided in the compact
disk (CD) in the back cover jacket of this report. Appendices F and R are documents developed by
Representatives of the U.S. Army Corps of Engineers prior to the Workshop and subsequent to the
availability of the draft of this report. These two appendices address various aspects of the use of the
two models exercised in this workshop for the prediction of beach performance. Section 4 presents







the procedures for and results from a quantitative assessment of eight examples for which measured
results were available as well as predictions from the two models. Section 5 presents a summary and
conclusions and Section 7 provides references cited in this report.

3.0 COMPARISON OF METHODS FOR PREDICTING PERFORMANCE OF BEACH
NOURISHMENT PROJECTS

3.1 Introduction

Beach nourishment technology is fairly young and the degree to which available calculation methods
agree with reality over a broad range of design conditions is poorly established. By this series of
workshops, we hope to contribute to: (a) An improved understanding of the predictability of present
calculation methods, and (b) The establishment of a basis for and initiation of efforts to advance this
capability. One approach toward the improvement of beach nourishment technology, and that which
will be followed here is to establish a framework for the calculation of project performance and to
compare the results of calculations of the performance of beach nourishment projects with
monitoring results. The State of Florida is fortunate that monitoring results are available for a
number of beach nourishment projects and thus can be compared with available methodology. The
comparison of the measured performance of these projects with the predictions of an established
methodology that is "blind-folded" in the sense that two individuals should predict the same
performance is valuable and is one of the approaches of this workshop.

3.2 Approach

The approach adopted in this workshop for the evaluation of capabilities in prediction of beach
nourishment project performance was to select a number of projects with ideally both design
information and monitoring results available. The most often applied beach nourishment design
methodology is the U.S. Army Corps of Engineers model "GENESIS" which has been described in
a number of documents (Hanson, 1989; Hanson and Kraus, 1989) and will not be discussed here
except to note that, in general, calibration and verification phases form essential components of the
process leading up to the design and prediction phases. The other model referred to as "DNRBS" has
a number of advantages for projects in the State of Florida. No calibration is required and graphs are
available which present recommendations for most of the parameters required in beach nourishment
design in Florida and thus allows a "blind-folded" design, that is two individuals should predict the
same results. For brevity, GENESIS and DNRBS will be referred to here as "detailed" and "simple",
respectively although the terms "comprehensive" and "idealized" have been suggested. Table 1
presents the eight projects selected for examination in this workshop. As indicated, the monitoring
information available for comparison purposes ranged from substantial to none.

3.3 Results for Individual Projects

3.3.1 General

Information provided in the following sections is based on the presentations at the workshop as well
as other information available. For each project, material distributed at the Workshop is included as
an individual appendix to this report. In addition to the discussions presented in the main body of







this report and the material in the appendices, the CD in the jacket on the inside back cover of this
report includes the Powerpoint presentations for the individual case studies.

Table 1
Projects Examined in the Workshop

Monitoring
Year Detailed Methodology Monito
Project Results
Project IConstructed Predictions Available? Res
Available?
Manatee County 1992-1993 Yes Yes
Martin County 1995-1996 Yes Yes
Captiva Island 1996 Yes Yes
Longboat Key 1997 Yes
Ocean Ridge 1998 Yes Yes
Key Biscayne 1987 Yes Yes
Juno Beach Completed Yes No
January 2001
St. Johns County Not Yet Yes No
Constructed

3.3.2 Manatee County Project

Documentation of the performance of this project is more comprehensive than for most projects.
Construction of this project was initiated on December 24, 1992 and completed on February 24,
1993. The "Storm of the Century" occurred in March 1993, shortly after completion of the Project.
A total of 2.21 million yd3 of sand was placed over a project length of 4.7 miles. The long-term
background erosion rates for this project range from approximately 1 to 4 feet per year (Dean et al.,
1998). The short-term rates are similar.

Predictions and measurements of volumetric performance as provided in the presentation are in
Figure 1. It is seen that GENESIS predicts a nearly linear decrease in volume of 40,000 yd per year
whereas DNRBS predicts that the volume decreases rapidly initially, then decreases more slowly
later in the life of the Project. Additionally of interest is that the measured volumes remaining agree
well with DNRBS for the first 20 months and after approximately 60 months, the measured volume
remaining increases and after 66 months agrees better with GENESIS. The explanation for the
increase in volume within the project area is unknown.

The predicted and measured longshore distributions of volume densities 4.8 years after nourishment
are presented in Figure 2 where it is seen that the DNRBS predictions are somewhat better than
GENESIS which predicts that the remaining fill volume is very similar to that at the time of
construction.










MANATEE COUNTY SHORE PROTECTION PROJECT
Fill Remaining in Project Area: Measured and Predicted


2400000


0 20 40 60 80 100
Time [months]


120


Figure 1. Measured and Predicted Volumetric Performance of the Manatee County
Beach Nourishment Project.

MANATEE COUNTY SHORE PROTECTION PROJECT
Longshore Distribution of Fill: Measured and Predicted

200,000
~200,0o0- r-I-- F-OST (~luil.)



140,000 -


20,000
180.000 -- ^ GENESI-





1.=D NRBS


-33 -32 -31 -30 -29 -28 -27 -28 -25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12
FDEP Monument Number (South to North)


Figure 2. Measured and Predicted Longshore Distributions of Volume
Density Remaining After 4.8 Years. Manatee County Beach
Nourishment Project.







The proportional volume and plan areas remaining as determined by Wang and Dean (2001) are
shown in Figure 3. It is seen that as of the last survey included here (February 1999, some 6 years
after construction), 88% of the volume remained in the project area and 41% of the plan area
remained. Of course, the Project performance is not uniform in the longshore direction and there are
segments of the nourished shoreline where the performance is substantially better than the average
and others where the performance is substantially worse. The nourishment sediments for this project
were slightly smaller than the native sediments which may account for the somewhat greater loss of
plan area than the usual approximately 50% of the volume remaining.

No predicted renourishment interval was provided for this project using GENESIS. This case study
was presented by Tom Smith of the Jacksonville District of the U.S. Army Corps of Engineers.



0.9 ---- pro rtiona ^ Vume:
S 0.8 :
C- -0.7 -




0.4
-o




2 0.2
0.1 -
0.0 i
0 1 2 3 4 5 6
Time After Construction (Years)

Figure 3. Proportional Volumes and Plan Areas Remaining Within Project
Limits. Manatee County Beach Nourishment Project. Based on Monitoring
Results (Wang and Dean, 2001).

3.3.3 Martin County Project

Construction of the Martin County Project commenced in December 1995, was completed in April
1996 and comprised the placement of 1.34 million yd3 of sand along a project length of 3.75 miles
of shoreline. Although the long-term erosion rates throughout the nourishment area are modest (= 1
ft/year), the average over the calibration period was approximately 3 ft/year and varied considerably
in the longshore direction. The predicted renourishment interval based on the GENESIS model was
determined to be 11 years. The values of the two sediment transport coefficients used in the
GENESIS calibration were K, = 0.1 and K2 = 0.1.

The performance of this project has differed from predictions and expectations more than any other
project in the State of Florida and certainly some of this anomalous response is due to the unusual








number and intensities of storms which have occurred starting in March 1996 and continued
throughout the Project life.


Figure 4 shows the volumetric changes as presented at the Workshop. It is seen that after 4 years,
only 31% of the volume remains within the Project area. Figure 5 presents comparisons of measured
and predicted shorelines along the project from 1995 to 1999. It is seen that the measured post-
construction shoreline changes (recessions) are greater than predicted by either GENESIS or
DNRBS; however, DNRBS provides better agreement for this time period. The presentation of this
case study was by Cynthia Perez of the Jacksonville District of the Corps of Engineers.


IS


12
& 1.0


I 0
0 04


.. ... .. .. .. .. .. .. .. . .... "... ...... .... .... ..... ......... .......... i....

. ..-- .. .. .. .-- --- .. .

- f4--- rt SD -S--'- 0. .. -..
. . . . . ?- . ~ I... . .
; - , : , ,


Figure 4. Measured and Predicted Volumes Remaining. Martin
County Beach Nourishment Project


0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000
Distance South of R-1 in Martin County (ft)



Figure 5. Comparison of Measured and Predicted Shoreline
Changes. Martin County Beach Nourishment Project, 1995-1999.







3.3.4 Captiva Island


The Captiva Island beach nourishment project that was addressed in this Workshop was completed
in 1996 with the addition of 817,300 yd3 of sediment. As of the last survey prior to the Workshop
(November, 1999), 637,000 yd3 remained. The comparison between the measured and predicted total
volumes remaining is presented in Figure 6. The measured volumes remaining within the Project
area are somewhat surprising and show that volume remaining in the Project area first increased and
later decreased. GENESIS predictions are nearly linear and overpredict the losses. The presentation
of this case study was by Mike Jenkins and Tom Campbell of Coastal Planning and Engineering.

3.3.5 Longboat Key

The Mid-Key Longboat Key nourishment project reported here was completed in February 1997.
Figure 7 presents a comparison of the measured and DNRBS (here called "Dean (1988) Diffusion
+ Recession Model") predicted volumetric remaining. It is seen that the DNRBS results are quite
good. No graphical results were presented for the total volumes predicted by GENESIS, although
the write-up stated that "The simulation indicated a reasonable performance of the fill, though key
historic 'hot spot' regions were not evident within the model. Recession amounts within the model
were less than historic rates in the Mid-Key region. Subsequent monitoring has indicated an under-
prediction of the losses by the GENESIS model." Figure 8 presents comparisons of the measured
and predicted shoreline changes. The predicted changes by DNRBS are in somewhat better
agreement with the measurements than are those based on GENESIS. The presentation of this case
study was by Mike Jenkins and Tom Campbell of Coastal Planning and Engineering.


3.3.6 Ocean Ridge

The Ocean Ridge Shore Protection Project was constructed in early 1998; at the time of the
Workshop, one year of data was available for comparison. In addition to nourishment with 784,300
yd3, this project included eight T-head groins located immediately south (downdrift) of South Lake
Worth Inlet (also called Boynton Inlet) and the removal of eleven derelict groins.

The GENESIS modeling included a calibration/simulation phase and a prediction phase. The
calibration/simulation phase was based on shoreline comparisons and encompassed the period
January 1975 to November 1993. Results are shown in Figure 9. The simulation of future
performance for a six year period is shown in Figure 10. The following values were adopted in the
GENESIS calculations: K, = 0.245 and K2 = 0.300. As shown in Figure 11, this application employs
a somewhat elaborate process of "back-refracting" the waves to deep water, then uses these waves
as input to GENESIS.









PROJECT PERFORMANCE CAPTIVE ISLAND, FLORIDA


100% i I




1 80%

B
80% :


0
-- --- -* ---|---^ - - ;; *

IT
5.. .
"ID
... - - -

40% .. .........

0
... ... .. .. ... .... .. ..... .... ... ..


20% -



.. . .. . .... -
C_ r_ 9_ t- 1* Cl :_ _ " 9_ r" C t" I t" _- Z1o




--4-GDM Preicted Peformance --- Observed Performance Based on Survey Data A Predited DNRBS Performance

Figure 6. Comparison of Measured and GENESIS Predicted Volumes Remaining. Captiva Beach Nourishment Project.









Performance of Longboat Key 1997 Mid-Key Nourishment


100%-



80% -


60%



40%



-1n


0 %I I I I I I I I I I I I I I I I I I II I I I I I I I I
0) -~ 03 0
0 > K 0 -

-O tO o ? o

I--*-- Dean (1988) Diffusion + Recession Model ..-... Diffusion Only -- Obsered Project Performance

Figure 7. Comparison of Measured and Predicted Percent Volume Remaining by DNRBS.
Longboat Key Beach Nourishment Project.

Expected versus Observed Fill Performance, Longboat Key, FL


-150 1
9000


12000 15000 18000 21000 24000
Distance north of New Pass (feet)


27000 30000 33000


...... Modeled Shoreline Change Post Construction to Year 3
-- Observed Shoreline Change Feb. 1997 Post Construction to Aug 2000
+ FDEP Monuments
- - Diffusion Model 3-year Estimate


Figure 8. Measured and Predicted Shoreline Changes. Mid-Key Longboat Key Beach Nourishment
Project, February 1997 to August 2000.


l l l l lI I I ll ll rllI l I













Ocean Ridge Verification Simulation
1 January 1975 to 30 November 1993
listenn uh telsa ll (INe)
I0 I O 10 110l I0 IU0 1101 3 400 10 I 110 1 00 00 IIU 00 701M I l I M III 1 0000I II l Io I6 0 110s tsI


I sI t < I ---l I ---I ---i -l Popoedp rojoIolIA li --- --

=I I- -1-





........_ .
........rt... ..... .. .
- -- -- -,..'* -"- -- -- KI-- K*.

--------........................ ,
-"' "'"" r" rrnm nn mi 1 1 nmu 1111111 .mn 111 m m 1 mn min. mnr


10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
genesis grid cell

Figure 9. Calibration Results of GENESIS With Historical Data. Ocean Ridge Beach Nourishment
Project.


Ocean Ridge GENESIS Simulation Beach FIII/8 Groins
K,=0.245
K,=0.300
uuiDr~ UII0 50157I*


e cnats south of south jetty (fe
4000 5000 6000 7000


000 9000 10000 11000 1200


- .L.llII.I. i -L l iu ii i iLL L II l I i L i


20 30 40 50 60 70 80


90 100 110
genesis grid cel


120 130 140


150 160 170


180 190 200


olsen associates, inc

Figure 10. Predictions With GENESIS. Ocean Ridge Beach Nourishment Project.




The DNRBS results are shown in Figure 12. Some difficulty was encountered in modeling with
DNRBS and it was considered that the GENESIS results were more valid. Due to the short time
available for modeling, the approach to introducing bypassing at the inlet was not represented
directly in DNRBS. Instead an abnormally small value of the sediment transport coefficient (K =
0.25) was used for this model.


11


300

" 250

& 200
0
S150



C 50



. -50


-100














































Develop time series of
mechanical and natural
sand bypassing


Figure 11. Flow Diagram

Calibration Method. Ocean

Nourishment Project.



Ocean Ridge DNRBS Simulation Beach FIUI/8 Groins
jltly length 600 fil
qetf 0.000
alpha 90 degrees
K 0.25
non-uniform background erosion


for GENESIS

Ridge Beach


- jsoe 5 A= u 2uw 5u=











liTy I




'i '' Tl~ ,~. ,, T T O lf 11 TT I. T] 1 II I r


S.% i


olsen associates, mc


Figure 12. Predictions Using DNRBS. Ocean Ridge Beach Nourishment

Project.

12


300

250

200

150

100

50
0
0


-100


stnc Souh o South Jey (t)
Distance Soush oa SoulS Jully (1ul)









Figure 13 presents a comparison of the measured and predicted results fifteen months after
construction. The differences between the two models are relatively small (although again the
necessity of using an unusually small value of K in DNRBS is noted). Neither of the two models
predicts the erosion near the south end of the project. The presentation of this case study was by
Chris Creed of Olsen Associates, Inc.

Ocean Ridge GENESIS & DNRBS Simulation Beach FIII/8 Groins
Year 1 Results
GENESIS ONRBS
K,=0.245 K=0.25
K,=0.300 Distance south of south jetty (foot)
1000 2000 3000 4000 000 60000 7000 1000 900 10 0000 1000 1200


S250 GENESIS
; 'iti ( iltlal lay, 998) DN BS

S ,,5



a -50 ......-^ ^- ^ -?^ --
200







-100 intli Ilinitn iIln nmII liIrIn Innr n irn ilm nnm I in iti nnnr n II a n listruri linitlm IInn r n ITIIT ll iinit ann iiiini
10 20 30 40 50 60 70 80 90 100 120 1 130 140 150 160 170 180 190 200
genes gild cel


Figure 13. Comparisons of One Year Monitoring Results With Predictions by
GENESIS and DNRBS.



3.3.7 Key Biscayne

The forthcoming Key Biscayne Beach Nourishment Project had not been constructed at the time that
the workshop was conducted. Two earlier projects had been constructed as follows. Crandon Park
had been nourished in 1969 with the application of 196,000 yd3 of sand and Key Biscayne and Bill

Baggs Park were nourished in 1987 with 420,000 cubic yards of sand. Comparisons were presented
for both projects. The calibration phase of the GENESIS model was conducted for the period 1962-
1974 and the verification phase was carried out for the period 1987 to 1990. The values used for the
sediment transport coefficients were Kz = 0.2 and K2 = 0.1. The calibration results are presented in
Figure 14 where the monitoring results are compared with the GENESIS and DNRBS calibrations.
It is noted that the GENESIS and DNRBS calibrations use background erosion rates based on
different time fames. Figure 15 compares measured and predicted shoreline changes from 1962 to
1987 which included the 1969 project. Figure 16 presents comparisons of measured and predicted
performances for the period 1987-1990 which included the 1987 Key Biscayne beach nourishment
project. GENESIS appears to provide better agreement than DNRBS; however, both models fail to
predict adequately the large erosion immediately north of the project. This case study was presented

by Rajesh Srinivas of Taylor Engineering.














































Figure 14. Calibration Results Based on GENESIS and DNRBS. Key Biscayne Beach
Nourishment Project, 1962 to 1974.


Key Biscayne 1962-1987


275
250
225
200
175
150
125
100
75
50 o
S 25


I -50
-75
-100
-125
-150
-175
-200
-225
-nfl


Distance South of R-92, ft

Figure 15. Measured and Predicted Shoreline Changes. Key Biscayne 1962-

1987.


___-.... ---J ..... ------L --i-J--- ..
So Measured
. .- ----t ,-- ------ -- ---- --- ------- -- --- Predicted (GENESIS)
S--- --- -- --- -- Predicted (DNRBS)
--- --- ---------- --- -- -r ----- ---r- -- ------ --- --- -------- -- ---
-- -- --- --- --- --- --------- ---- ---- - ------

----, ----- --- -, --- --- --- ------------------
0 I -----;---------^ :iil::




A v-.---^ - U',- - [ -*- -- --- - ---- -!--.
- _-- --- ------- -_ -. .-- ---- --- -- .---- _-r --- --------r--- ---r--- -




-- J --- I ---. --- .--- J ------- -- ---- ----L --- .... --- --- --- -- ---- ..J.-.


^_ _-_-.----u ~- \- - -I----* ^- -- --- I- --- 4-- ___J_--.
- --- .--- --- ----- --- --- --------






. ---'--------- F-- j----I----I--- ----- ------ --.--. -------- -- --- 1----
0



1- I I I L- l I I l- I i q
--~.----/, ,\ ,o ,l , V, .-. . . ] , ,-


... r- .... r- -r- 1---- r-' -r--- r-- -n n - - - - .r. . .



.... l-- q ..... .... -~- .. .. I---;~-- -4. . .F l - .' .l I. .




























Figure 16. Comparison of Measurements and Predictions Based on
GENESIS and DNRBS for 1987 Key Biscayne Beach Nourishment Project.



3.3.8 Juno Beach

Completion of construction of this project was in January 2001, thus no monitoring results were
available at the time of the Workshop. The material available included predictions by the two
models. Figure 17 shows a comparison of the predicted performances by the two models.


The brief report stated, in referring to the GENESIS model "Problems were encountered in the
calibration and performance of the model. Erosion and accretion trends were over emphasized within
the model. In particular, an observed 'hot spot' region within the project area was predicted to be
accretional within the GENESIS simulations."

The discussion of the results obtained through DNRBS modelling stated "Project losses predicted
by the diffusion model are significantly greater than those predicted within the GENESIS
simulations. These were accounted for with the project by the addition of diffusion losses, though
these losses should theoretically be within the GENESIS simulations. The losses predicted by the
diffusion model are in line with losses measured in a similar project within the region (Delray
Beach), suggesting an underprediction of losses by the GENESIS simulations." The presentation of
this case study was by Mike Jenkins and Tom Campbell of Coastal Planning and Engineering.









FIGURE IV-B


Predicted Shoreline Position 5 Years after Project Completion,
Juno Beach, FL

140
120 -------- ------
100
E
,o 80 .
.. 60-.--- -_ _


0"

2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Distance from Jupiter Inlet (miles)
-Initial Fill Width ..... Genesis Model --Dean


Figure 17. Predicted Performances of Juno Beach Project by GENESIS and
DNRBS, 5 Years After Project Construction.



3.3.9 St. Johns County

As noted, the St. Johns County beach nourishment project has not yet been constructed. Thus, this
project comparison was limited to a comparison of the two model results. This project as designed
will comprise the placement of 3.37 million yd3 over a project length of 2.5 miles, resulting in a
volumetric density added of 256 yd'/ft! The native and nourishment grain sizes are well matched.
Figure 18 compares 10 year predictions by GENESIS and DNRBS. The coefficients used in the
GENESIS calibration were K, = 0.58 and K2 = 0.45. Tom Smith of The Jacksonville District of the
Corps of Engineers presented this case study.


4.0 QUANTITATIVE MEASURE OF PREDICTIVE SKILL

Graphical results are presented in the main body of this report, in the appendices relating to the
individual projects and in the Power Point presentations at the Workshop. As noted previously, these
Power Point presentations are provided in a CD in the inside back cover of this report.

One approach to judging the predictive performance of the two models considered in this Workshop
is visually, that is to simply examine the available plots. However, it is desirable to provide a less
subjective measure, one that is quantitative and independent of the individual carrying out the
comparisons. For this purpose, the Normalized Standard Deviation (NSD) is introduced below. This







measure is defined as the ratio of the root-mean-square deviations between the measurements and
the model being compared to the root-mean-square of the measured quantity. Other measures of
agreement could be established and compared. If the NSD is zero, the agreement between the model
predictions and measurements is exact. NSD values of unity or greater are poor quantitatively,
although the form of the predicted values of the quantity being compared may be quite similar to that
of the measured values. The NSD was calculated only for those cases for which all three values
were available: Measured, GENESIS predictions and DNRBS predictions. Full information is
lacking for other cases. In addition to the NSD values, the Reader is encouraged to examine all
additional information provided by the Workshop Participants and contained in this report.


137 138 139 140 141 142 143 144 145 146 147 148 149 150 151
FDEP Monument Number (South to North)

Figure 18. Predictions of Volumetric Change After 10 Years for St. Johns
County Project.


The NSD is defined as:


NSD =


I
E (vi)
I


where the variable "v" can represent total volumes, alongshore distribution of volume density or
alongshore distribution of shoreline changes. The subscripts "m" and "c" denote measured and


ST. JOHNS COUNTY SHORE PROTECTION PROJECT
Longshore Distribution of Fill: Measured and Predicted







calculated, respectively. The quantities "i" and "I" denote the individual variable and the total
number of values in the summation, respectively.

The eight case studies examined in this report provided the basis for calculating a total of nine NSD
values based on five of the case studies. The results are presented in Table 2 where it is seen that in
five of the individual cases, DNRBS provides a substantially better fit than GENESIS (ratio of the
two NSD values greater than 1.6), in two of the cases, DNRBS is marginally better (ratio ranges
between 1.12 and 1.15), in one case, the two NSD values are identical (0.945) and in one case
GENESIS provides marginally better results (ratio is 1.005). The fourth column in Table 2
references the plots on which the calculated NSD values are based.

Table 2

Summary of Normalized Standard Deviations for Projects Having
Measured Data and Two Model Predictions Available

Normalized Standard Deviation,
Project Type of Data Time Span Reference NSD for Model
Compared
I GENESIS DNRBS
Manatee Volumes 1993 2000 Figure 1 0.382 0.159
County Volume 1993- 2000 Figure 2 0.648 0.320
Densities
Martin County Volumes* 1995 1999 Figure 4 (modified) 0.378 0.337
Shorelines 1995 1999 Figure 5 1.272 0.754
Longboat Key Shorelines 1997-2000 Figure 8 1.060 0.639
Ocean Ridge Shorelines 1999 2000 Figure 13 0.389 0.391
Key Biscayne Shorelines 1962 1974 Figure 14 1.154 1.003
Shorelines 1962 1987 Figure 15 1.289 0.800
Shorelines 1987 1990 Figure 16 0.945 0.945
*Note: This comparison was based on a modified version of Figure 4 in which all predicted initial volumes
were the same = 1.3 million cubic yards.



5.0 RESULTS, FINDINGS AND RECOMMENDATIONS

5.1 Use of Models in Prediction of Beach Nourishment Performance

Numerical models are useful in predicting the performance of beach nourishment projects. However,
uncertainties will always remain in the accuracies of the predictions due to: (1) The variability of the
actual nearshore climate affecting the project will always be different than that used in the
predictions, (2) Natural and nourished shorelines are "noisy"; therefore, even if the exact wave
climate affecting the nourishment were known in advance, the predictions would differ from reality,
and (3) The models will never be "perfect" in representing the processes. Thus, there will always be
a deterministic (predictable) and a probabilistic (unpredictable, except in the statistical sense)
component of the project evolution. Comparisons such as those conducted here provide an effective







means of quantifying these two components as well as identifying the strengths and weaknesses of
the two models evaluated in this workshop effort. Based on the results developed in this Workshop,
comments follow describing the characteristics of the two models and their applications.

5.1.1 GENESIS

* This model predicted an almost linear decrease of volume with time within the project area, for
all cases in which these results were presented. See, for example, the results for Manatee County
(Figure 1), Martin County (Figure 4), Captiva Island (Figure 6), St. Johns County (Slide 18 of
presentation on CD), Juno Beach (Slide 4 of presentation on CD) and Key Biscayne (Slide 16
of presentation on CD). This is in contrast to the usual behavior in which the loss rates are
greater at first and diminish with time. One possible explanation is that the small sediment
transport coefficients (Ki and K2) reduce the diffusive component of the evolution to a degree
that the background conditions established in the calibration and verification phases comprise
the main predicted evolution.

* If the offshore contours are convoluted such as near the ends of a barrier island, it is necessary
to employ an external wave model with GENESIS which accounts for these contours.

* Representative annual seasonal shoreline changes on the east coast of Florida are approximately
15 feet (Dewall, 1977). Thus if shoreline changes are to be used rather than volume changes
in the calibration phase, it is generally necessary to select a time interval substantially greater
than S/R, where S is the magnitude of seasonal shoreline change and R is the recession rate.

* The ranges of values of the two transport coefficients determined by calibration for the four cases
in which such values were presented were: 0.1 < K, < 0.58 and 0.1 < K2 < 0.45.

5.1.2 DNRBS

* The background shoreline changes are input directly into this model. In areas where offshore
shoals cause relatively short-term and rapid changes in the shoreline as was the case for the Key
Biscayne Project, short-term predictions should rely more on the short-term shoreline changes
rather than on the long-term changes as was done in this DNRBS application.

* The diffusive nature of the transport and continuity equations causes background shoreline
changes which vary substantially over short distances to be smoothed out rather than reproduce
the background shoreline changes. In those cases where this type of change is predominant, it
may be worthwhile to incorporate a feature that would reduce the rate of smoothing of the
observed background shoreline change rates.

* Application of this model for Florida projects is facilitated by the availability of design
information, and no calibration or verification is required. Thus two individuals calculating the
performance of a beach nourishment project should obtain the same approximate results.







5.2 Monitoring


The monitoring related material provided by OBCS at the meeting is presented as Appendix C.
Discussions encompassed a broad range of issues as described in greater detail below.

Beach profiles are surveyed for general, storm impact and project purposes. Survey issues included:
profile frequency, spacing, season and line length. Surveys in the vicinity of inlets were also
discussed as were the methods of surveying. The merits (costs and accuracies) of sea sleds versus
fathometers were discussed. It was noted that the most representative seasons for surveying were
when the beach is most advanced and when it is most recessed since at these times, the beach
position is approximately stationary. However, if surveying were limited to these times, survey costs
would increase due to the need for many surveys in a relative short period of time and then little
work at other times of the year. It was agreed that annual surveying of projects was justified. OBCS
plans to have a central repository for survey data on their WEB Site. The value of wave data to the
State's beach program was discussed. One application of wave data is in interpreting the
performance of beach nourishment projects. Concern was expressed relative to both the duration and
magnitude of required commitment by the State in the comprehensive development of wave data.

It was determined that a monitoring policy statement was not appropriate at this time and that
additional information would be organized by the Staff of OBCS for later consideration and a
recommendation by CETAC.

5.3 Rule Revision and Sand Specification

The OBCS had prepared in advance a draft Rule Revision which is presented as Appendix D. The
intent of the proposed rule was to ensure that nourishment sediments were reasonably compatible
with native sediments. Significant attributes of sediments under consideration for beach nourishment
include: size, color, mineralogy, organic content and tendency for cementation. Discussions included
details of the Rule and general issues related to acceptable sediment characteristics. A committee
was appointed to develop a recommendation for consideration by CETAC. The committee consisted
of: Tom Campbell, Chair, Bob Brantly, Skip Davis, Randy Parkinson and Doug Rosen.

6.0 ACKNOWLEDGMENTS

The Author is indebted to all the participants in this second CETAC workshop. A special thanks
goes to those who presented material which contributed so greatly to the overall significance of this
effort. Of course, the workshop was possible only through the support provided by the Office of
Beaches and Coastal Systems of the Florida Department of Environmental Protection. Ms. Echo
Gates of OBCS worked quietly behind the scenes and improved significantly the quality of the
Workshop and this report.

7.0 REFERENCES

Dean, R. G. and J. Grant (1989) "Development of Methodology for Thirty-Year Shoreline
Projections in the Vicinity of Beach Nourishment Projects", UFL/COEL-89/026, Coastal and
Oceanographic Engineering, University of Florida, Gainesville, FL.







Dean, R. G., J. Cheng and S.B. Malakar (1998) "Characteristics of the Shoreline Change Along the
Sandy Beaches of the State of Florida: An Atlas", UFL/COEL-98/015, Department of
Coastal and Oceanographic Engineering, University of Florida, Gainesville, FL.

Dewall, A.E. (1977) "Littoral Environmental Observations and Beach Changes Along the Southeast
Florida Coast", Report No. CERC Technical Paper No. 77-10, U.S. Army Corps of
Engineers, Coastal Engineering Research Center, Fort Belvoir, VA.

Hanson, H. (1989) "GENESIS A Generalized Shoreline Change Numerical Model," Journal of
Coastal Research, Vol. 5, No. 2, p. 1-28.

Hanson, H. and N.C. Kraus (1989) "GENESIS: Generalized Model for Simulating Shoreline
Change, Report 1, Technical Reference," Technical Report No. 89-19, Coastal Engineering
Research Center, Waterways Experiment Station, Vicksburg, MS.

Wang, Z. and R. G. Dean (2001) "Manatee County Beach Nourishment Project: Performance and
Erosional Hot Spot Analysis", .UFL/COEL-2001/003, Coastal and Oceanographic
Engineering, University of Florida, Gainesville, FL.














APPENDICES





























APPENDIX A

WORKSHOP PARTICIPANTS






Gary Anderson
PBS&J
7785 Baymeadows Way, Suite 202
Jacksonville, FL 32256
glanderson@pbsj.com




Bob Brantly
Office of Beaches and Coastal Systems
Florida Department of Environmental Protection
Marjorie Stoneman Douglas Building
Tallahassee, FL 32399
robert.brantly@dep.state.fl.us





Chris Creed
Olsen and Associates, Inc.
4438 Herschel Street
Jacksonville, FL 32210
ccreed@olsen-associates.com






Chuck Dill
Alpine Ocean Seismic Surveys, Inc.
Chuck@alpineocean.com









Emmett Foster
Office of Beaches and Coastal Systems
Florida Department of Environmental Protection
Marjorie Stoneman Douglas Building
Tallahassee, FL 32399
emmett.foster@dep.state.fl.us


Kevin Bodge
Olsen and Associates, Inc.
4438 Herschel Street
Jacksonville, FL 32210
kbodge@olsen-associates.com




Tom Campbell
Coastal Planning and Engineering
2481 NW Boca Raton Boulevard
Boca Raton, FL 33431
tcampbell@cpe.dynip.com






Al Devereaux
Office of Beaches and Coastal Systems
Florida Department of Environmental Protection
Marjorie Stoneman Douglas Building
Tallahassee, FL 32399
alfred.devereaux@dep.state.fl.us





Karyn Erickson
Applied Technology and Management
2770 NW 43rd Street, Suite B
Gainesville, FL 32606-0995
kerickson@atm-s21i.com






Echo Gates
Office of Beaches and Coastal Systems
Florida Department of Environmental Protection
Marjorie Stoneman Douglas Building
Tallahassee, FL 32399
echo.gates@dep.state.fl.us


A-2






Mark Gravens
Coastal and Hydraulics Laboratory
Waterways Experiment Station
Vicksburg, MS 39180
Mark.B.Gravens@wes02.usace.army.mil






Ed Hodgens
Jacksonville District
U.S. Army Corps of Engineers
400 West Bay Street
P. O Box 4970
Jacksonville, FL 32232-0019
ed.hodgens@saj02.usace.army.mil




Michael Jenkins
Coastal Planning and Engineering
2481 NW Boca Raton Boulevard
Boca Raton, FL 33431
mjenkins@cpe.dynip.com






Linda Lillicrop
Mobile District
U.S. Army Corps of Engineers
Mobile, Alabama
Linda.S. Lillicrop@sajm.usace.army.mil






Cynthia B. Perez
Jacksonville District
U.S. Army Corps of Engineers
400 West Bay Street
P. O Box 4970
Jacksonville, FL 32232-0019
Cynthia.B.Perez@saj 02.usace.army.mil


Joe Gurule
Jacksonville District
U.S. Army Corps of Engineers
400 West Bay Street
P. O Box 4970
Jacksonville, FL 32232-0019
Joseph.E.Gurule@saj02.usace.army.mil





Steve Howard
Olsen and Associates, Inc.
4438 Herschel Street
Jacksonville, FL 32210
showard@olsen-associates.com






Mark Leadon
Office of Beaches and Coastal Systems
Florida Department of Environmental Protection
Marjorie Stoneman Douglas Building
Tallahassee, FL 32399
mark.leadon@dep.state.fl.us





Brett Moore
Humiston and Moore Engineers
10661 Airport Road N., Suite 14
Naples, FL 34109
bdm@humistonand moore.com






Cameron Perry
Coastal Systems International
464 South Dixie Highway
Coral Gables, FL 33146
cperry@coastalsystemsint.com


A-3





Michael Poff
Coastal Engineering Consultants, Inc
3106 South Horseshoe Drive
Naples, FL 33942
mpoff@cecifl.com






Tom Smith
Jacksonville District
U.S. Army Corps of Engineers
400 West Bay Street
P. O Box 4970
Jacksonville, FL 32232-0019
thomas.d.smith@saj02.usace.army.mil





Bruce Taylor
Taylor Engineering, Inc.
9000 Cypress Green Drive, Suite 200
Jacksonville, FL 32256
btaylor@taylorengineering.com





Paden Woodruff
Office of Beaches and Coastal Systems
Florida Department of Environmental Protection
Marjorie Stoneman Douglas Building
Tallahassee, FL 32399
paden.woodruff@dep.state.fl.us


Doug Rosen
Jacksonville District
U.S. Army Corps of Engineers
400 West Bay Street
P. O Box 4970
Jacksonville, FL 32232-0019
douglas.s.rosen@saj02.usace.army.mil




Rajesh Srinivas
Taylor Engineering, Inc.
9000 Cypress Green Drive, Suite 200
Jacksonville, FL 32256
Rsrinivas@taylorengineering.com






Mike Walther
Coastal Technology Corporation
3625 20th Streeet
Vero Beach, FL 32960
mpwll@aol.com






Bob Dean
Department of Coastal and Oceanographic
Engineering
University of Florida
P. O. Box 116590
Gainesville, FL 32611-6580
dean@coastal.ufl.edu































APPENDIX B

WORKSHOP PROGRAM




(OATAL ENGI[NEERiN TE(HNi(AL
ADVIORY COMMITTEEE

WORKSHOP NO. 2
AMONORiNG GUiPDiEfVS AIV BACti
NOURiStHMEN DESiGND


Sea Turtle Inn
Jacksonville, Florida


Tuesday, October 24, 2000
to
Thursday, October 26, 2000


Florida Dept of Environmental Protection
Office of Beaches and Coastal Systems







Tuesday, October 24

1:00-1:15 Welcome...........................Tom Campbell

1:15-1:30 Introduction of Topics for Discussion
........................................ ..........Bob Dean

1:30 2:30 Rule Revision and Sand Specification
................................................ Bob Brantly

2:30 3:00 Monitoring Issues ................. Bob Brantly

3:00 3:15 Break

3:15 5:00 Monitoring Issues ...........................Group

Wednesday, October 25

8:00 10:00 Introduction to Model Calibration with
Mid-Town Beach as an Example...............
....................................................Bob D ean

10:00- 10:15 Break

10:15 10:50 Duval County Beach Restoration ..............
................................................ U SA CE-Jax

10:50 11:25 Delray Beach Nourishment............ CP&E

11:25 12:00 South Lake Worth Inlet ............................
.....................Chris Creed-Olsen Associates

12:00- 1:30 Lunch

1:30 2:10 Martin County Beach Restoration ..............
................................................ U SA C I:-Jax


2:10 2:45 Key Biscayne Beach Nourishment ...........
.......... Rajesh Srinivas-Taylor Engineering

2:45 3:00 Break

3:00 3:35 Longboat Key Beach Restoration.... CP&E

3:35 4:10 Captiva Island Beach Restoration.... CP&E

4:10 4:45 Anna Maria Island ............... USACE-Jax

4:45-5:00 Working Group Assignments .................

Thursday, October 26

8:00 10:00 W working Groups ....................................
Role of Simple and Complex Models
in Beach Design
Needs for Model Development
Needs for Model Data Organization
Assessment of Design Accuracy
Calibration Methodology
Monitoring
Others (?)

10:00- 10:15 Break

10:15- 11:15 Working Group Presentations.....................

11:15-11:45 Future CETAC Issues.........Tom Campbell

11:45 12:00 Closing Remarks.......................Bob Dean

12:00 Adjourn






























APPENDIX C

MONITORING PROGRAM OF THE
OFFICE OF BEACHES AND COASTAL SYSTEMS











FDEP, Office of Beaches and Coastal Systems
Statewide Coastal Monitoring Program
Data Collection and Processing

Table 1. 5-Year Data Collection and Processing Schedule


Fiscal Year

1999/00






2000101




2001/02




2002/03




2003/04




2004/05


Location

East Coast (Nassau Martin)






SW (Pinellas Collier)




SE (Brevard Dade)




NE (Nassau- Volusia)




NW (Escambia- Franklin)




SW (Pinellas- Collier)


Note: New technologies such as LIDAR and SHOALS will be incorporated as appropriate.


Data Collection & Processing

Digital Aerial Photography
(Processing only)
Videography
Conventional Survey (DEP Profiles)
(Nassau-Flagler)
Wave Program
(Work started in FY 00/01)

Digital Aerial Photography
Aerial Videography
Conventional Survey (DEP Profiles)
Multi-beam (Inlets TBD)
Wave Program

Digital Aerial Photography
Aerial Videography
Conventional Survey (DEP Profiles)
Multi-beam (Inlets TBD)
Wave Program

Digital Aerial Photography
Aerial Videography
Conventional Survey (DEP Profiles)
Multi-beam (Inlets TBD)
Wave program

Digital Aerial Photography
Aerial Videography
Conventional Survey (DEP Profiles)
Multi-beam (Inlets TBD)
Wave program

Digital Aerial Photography
Aerial Videography
Conventional Survey (DEP Profiles)
Multi-beam (Inlets TBD)
Wave program































APPENDIX D

SEDIMENT CRITERIA FOR BEACH NOURISHMENT PROJECTS


D-1
















10-19-00 Proposed revision of Rule


62B-41.007(2)(j)

All fill material being placed on sandy beach locations shall be sediment that is similar to
that which naturally would or does exist on the site in color, grain size, gradation and
carbonate composition. Fill material shall:
a) generally exclude peat and clay,
b) be free of construction debris and other foreign matter,
c) not contain greater than 5 percent by weight sediment smaller that 0.74 millimeters,
exclusive of quartz sediment, O
d) not contain greater than 5 percent by weight sediment larger than 4.75 millimeters,
e) generally exclude material larger than 19 millimeter, exclusive of shell material, and
f) not cause cementation or encrustation of the beach.
If the natural beach exceeds any of the limiting parameters listed above, then the fill
material shall not exceed the naturally occurring level for that parameter.

62B-41.008(l)(k)4.

Permit applications for inlet excavation, inlet bypassing, or beach restoration or
nourishment shall include a sediment analysis of the native sand at the beach placement
site and the sediment in the proposed borrow sites sufficient to determine the nature of
the material to be dredged and its compatibility with the existing beach sand pursuant to
Rule 62B-41.007(2)(j). The analysis shall be conducted in accordance with established
professional geological and engineering practice, and Office of Beaches and Coastal ^,-.-'-rs'.
Syatemr' rcognid rl guidOline-rs .


RMB
G:\Bchmgmt\Geotechnical,10.19-00.2 proposed rule.doc


D-2

























APPENDIX E


INTRODUCTION OF A "SIMPLE" METHOD FOR CALCULATING
BEACH NOURISHMENT PROJECT PERFORMANCE
WITH EXAMPLES FOR
DELRAY BEACH, FL, MIDTOWN BEACH, FL AND MANATEE COUNTY, FL

by

Bob Dean
Department of Civil and Coastal Engineering
University of Florida








APPENDIX E


INTRODUCTION OF A "SIMPLE" METHOD FOR CALCULATING
BEACH NOURISHMENT PROJECT PERFORMANCE
WITH EXAMPLES FOR
DELRAY BEACH, FL, MIDTOWN BEACH, FL AND MANATEE COUNTY, FL


1.0 INTRODUCTION

The purposes of this workshop are to better understand the present capabilities of beach nourishment
performance prediction and to establish approaches to advancing this capability. The specific
objectives are, through a number of case studies, some of which include comparison with monitoring
results, to evaluate our current capabilities using methodologies that will be termed here as "Simple"
and "Complex", to evaluate the merits of these two approaches and to recommend approaches for
further improvement.

The most often applied complex methodology is GENESIS which has been described in a number
of documents (Hanson, 1989; Hanson and Kraus, 1989) and will not be detailed here except to note
that, in general calibration and verification phases form essential components of the process leading
up to the design and prediction phases. The "Simple" model, also referred to as "DNRBS" herein to
be compared in this workshop has a number of advantages for projects in the State of Florida. Graphs
are available which present recommendations for most of the parameters required in beach
nourishment design. Additionally, this method requires no calibration and verification and thus a
substantial proportion of the design complexities is removed. The so-called "simple" method will be
described and illustrated with examples later. The following section presents and provides a general
discussion of some results which can be developed from beach nourishment theory. However, these
results will not be derived or discussed in detail, Rather, they will be considered as a basis for the
methodology to follow.

2.0 SEVERAL BEACH NOURISHMENT FUNDAMENTALS

Several beach nourishment fundamentals are presented and discussed briefly below.

2.1 Relative Insensitivity to Wave Direction

The performance of a project constructed with compatible sand on a reasonably long straight
shoreline can be shown to be relatively independent (within about 10%) of wave direction. This result
is quite significant since the characteristics of wave directions are much more poorly understood than
are wave heights and thus the designer can concentrate his/her efforts on the much more critical and
available wave height variable.


E-2








2.2 Superposability of Background and Project Components


Because the nourishment project always represents a small perturbation to the planform geometry,
it can be shown that it is possible to superpose linearly the effects of the transport and shoreline
changes due to the pre-existing system and that of the project. As indicated, this is due to the
relatively shoreline width increase compared to the project length. As an example, a project of 3 miles
length that increases the beach width by 100 feet results in an average planform angle of
approximately 0.7 degrees. This allows the tangent and sine of this angle to be represented by the
angle and justifies the superposition. This result is significant since it allows separation of the project
shoreline changes and transport from those due to the system prior to project construction. It is noted
that this small angle approximation forms the basis of the so-called "Pelnard-Considere" theory which
is applicable to beach nourishment planform evolution.

2.3 Project Evolution is Independent of Storm Sequencing

Based on idealized beach nourishment theory (the Pelnard Considere theory), the evolution of a
project at a particular time is relatively insensitive to the sequence in which previous storms occur.
This result can be extended to demonstrate that it is possible to represent the wave climate on a long
straight beach by a single effective wave height.

3.0 SIMPLE METHOD OF CALCULATING BEACH NOURISHMENT EVOLUTION

3.1 General

The simple method of calculating beach nourishment evolution is one developed and documented by
Dean and Grant (1989) in a report to the Division of Beaches and Shores (the predecessor to OBCS).
As noted, the desirable features of this method include: (a) No calibration nor verification phases are
required, (b) Nearly all parameters requiring specification are available in graphical forms, thereby
removing a substantial portion of the subjectivity in design. It is hoped that this workshop will
contribute to answering the dual questions: (a) Is this approach valid for design and if so in what
role?, and (b) Are any quantitative adjustments suggested by the case studies presented in this
workshop? The sections below describe and present the rationale for the simple method. The method
will be illustrated by application to the Delray Beach Nourishment Project, the Midtown Beach
Nourishment Project (which was stabilized by eleven groins) and the Manatee County Beach
Nourishment Project in later sections of this report.

3.2 Ad Hoc Transformation of Actual System to One With Straight and Parallel Bottom
Contours

A basis of the Simple Method is the transformation of the actual beach and nearshore system to one
with straight and parallel contours (one of which is the shoreline). This transformation is illustrated
in Figure E-1. Although the justification for this transformation is somewhat intuitive in nature and
certainly has its limitations, rationale is provided by the aforementioned superposability of the


E-3








background and project transport and shoreline change components. As will be discussed later, the
background transport will simply be superimposed on the project related transport which is calculated
on the transformed system. Upon completion of the project evolution in the transformed system, the
results are simply transformed back to the actual system.



-Shorelne Shorlin
ContourContours
















a) Initial Actual Shorene b) Initial Shoreline and
and Contours Contours to be Modeled.
Figure E-1. Conceptual Illustration of the Ad Hoc Transformation
of the Actual System to One With Straight and Parallel Bottom
Contours.
3.3 Specification of Parameters

The significant parameters in beach nourishment design include: (1) Effective wave height, (2)
Effective wave period, (3) Depth of closure, (4) Berm height, and (5) Sediment transport coefficient,
K. In cases where the nourishment will be placed in conjunction with or in proximity to one or more
structures, either the background transport or wave direction is also required. In the following
sections, the determination of the five parameters above will be described, followed by
recommendations for determining wave direction and background transport in those projects where
required.

3.3.1 Effective Wave Height

The effective deep water wave height is determined from Figure E-2. An example will be illustrated
later for the Midtown Beach Nourishment Project for which the value of effective deep water wave
height is 1.4 feet, and the Delray Beach Nourishment Project is 1.1 feet.


E-4






















1. 44r.
Del rd
I. It


Figure E-2. Recommended Effective Wave Height Around the State of
Florida.


3.3.2 Effective Wave Period

This variable is presented for the State of Florida in Figure E-3 where it is seen that the values for the
Midtown and Delray Beach projects are 6.6 seconds and 6.4 seconds, respectively.


.Ot~Jrn


Figure E-3. Recommended Effective Wave Period Around the
State of Florida.


E-5









3.3.3 Depth of Closure

Figure E-4 presents these results where it is seen that the recommended values for the Midtown Beach
and Delray Beach projects are 14.9 ft and 14.2 ft, respectively.


h. (Feet)
12 16 20 24


LL.
16
12
~-JA

MA
ST


CL






M1
1216 20 24
h. (Feet)


Figure E- 4.
Florida.


Recommended Depth of Closure, h., Around the State of


3.3.4 Berm Height

No figure has been prepared for the berm height as this is usually available from the historic data base
compiled by the Florida Department of Environmental Protection and also from profiles surveyed in
preparation for the project. Recommended values for the two projects of interest here are both 6 feet.








E-6


M____ 14.1ft
14.2f' 192C









3.3.5 Sediment Transport Coefficient, K


The recommended sediment transport coefficient in the so-called "CERC equation", K, is a function
of the median grain size, D, as shown in Figure E-5.


2.0


e 1.01


\ Result From This Stu ly,
- \Santa Barbara

S Relationship Suggesed
Previously
\ *





0.5 1.0
DIAMETER, D (mm)


Figure E-5. Variation of Sediment Transport Coefficient, K,
With Median Grain Size, D.



3.4 Application of Methodology

The original computer program, DNRBS, which was developed to predict the evolution due to a
single beach nourishment has been modified to represent multiple nourishments (renourishments).
In general, the actual longshore distribution of placed nourishment volume can be represented. The
application of DNRBSM will first be illustrated for the Delray Beach Nourishment Project for which
a total of 4 nourishments have been conducted since 1973, for the Midtown Beach Nourishment
Project which has been nourished once in late 1995 and which includes eleven groins and finally for
the Manatee County Project.


3.4.1 Evolution Prediction of the Delray Beach Nourishment Project

The Delray Beach, FL beach nourishment project was first nourished in 1973 and has been nourished
a total of four times with the timing and volumes as shown in Table 1. Figure E-6 shows the
alongshore volumetric distributions of the four nourishments. The annotated input file for DNRBSM


E-7








is presented in Figure E-7 for this project for zero background erosion and a wave height of 1.1 feet
in which the additional lines have been added between lines of data to allow space for the annotation.
For purposes here, the project results have been calculated for uniform background erosion rates of
0 and 2 ft/year and deep water wave heights of 1.1 and 1.2 feet and are presented in Figure 8. The
reason for the ranges in background erosion rates and wave heights here is to provide a measure of
sensitivity.

Table E-1
Timing and Quantities of Beach Nourishment Events at Delray Beach, FL



Nourishment Date Volume (Millions of Cubic
Number Yards)

1 July to August 1973 1.63

2 February to May 1978 0.70

3 September to October 1984 1.30

4 November to December 1992 1.02


.0.50 0.00 0.50
. -1 ohft PW


Figure E-6. Nourishment Densities for the Four Delray Beach Nourishment
Projects.


E-8











SAMPLE INPUT FOR DELRAY BEACH NOURISHMENT PROJECT

)*

Delray Beach Nour. Project, Wave Ht 1.2 ft, BE = 0.0 ft/year
^- Wt < PI.,,.( yCVID:^Y~rl <. ^y b ", DT 11-3 < ..^
1.20 6.4 85.0 90.0 180.dr- 528.0 86400.0 N .4
Ad e 1< ,e, ...'-. r "
14.2 6.0 1.10 1.34 0.0 1 180 10950 0 4

0.0 0.0 90000. 0.0 49500. 2.0 60000. 3.0
90000. 3.0 100000. 3.0 140000. 2.0
_-- rTY- I $ or V t
1 102e--zIN()* c"_S5

75 102 1 0.989

75 20.0
76 155.0
77 164.0
78 163.0
79 133.0
80 116.0
81 116.0
82 116.0
83 116.0 MoDAm
84 116.0
85 116.0
86 116.0
87 116.0
88 116.0
89 116.0 T7o "*.-sr\
89 116.0
91 116.0
92 116.0
93 116.0
94 116.0
95 116.0
96 112.0
97 107.0
98 105.0
99 105.0
100 105.0 /viNos C~)
101 90.0 Ny' o e)
102 8. -- --
78 1 1720 1.025
78 15.0
79 48.0 T7OUv (,)
80 49.0
81 67.0
82 86.0
83 86.0 Se5o-
84 86.0
85 104.0 Pjo (uPr& wvU
86 106.0
87 87.0
88 86.0
89 115.0
90 77.0


Figure E-7a. Input File for Delray Beach Nourishment Project (First Part).


E-9













91
92
93
94
95
96
97
98
99
100
101
75
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
85
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102


SCovvv-rnate)


0.(
0.(
0.c
0.c
0.0
15.
32.C
32.C
82.C
102.0
61.0
102
28.0
90.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
96.0
90.0
8.0
102
31.0
123.0
134.0
114.0
112.0
142.0
147.0
161.0
163.0
110.0
94.0
125.0
147.0
180.0
187.0
148.0
142.0
20.0


Figure E-7b. Input File for Delray Beach Nourishment Project (Second Part).


E-10


4076 0.993




























7057 0.848








Afo^'i's*^*^
lru~S rrf














t3


0)
r-r
i''



.. "l ^
E











Nourishment Project.
1970 1980 1990 2000 2010
Year
Figure E-8. Comparison of Monitoring and Calculated Volume Remaining. Delray Beach
Nourishment Project.



4.4.2 Evolution Prediction of the Midtown Beach Nourishment Project

As noted, this project was constructed with eleven groins to provide stabilization. A total of 880,000
yd3 was placed over a distance of 5,400 ft with placement commencing in October 1995 and
concluding in December 1995. Construction of the eleven groins started in December 1995 and was
completed in April 1996. The input file for the project with the groins present is presented in Figure
E-9. The evolution will be calculated with and without the effects of groins to illustrate their influence
on project evolution.

The calculated and monitored total volumes remaining in the project area from 1976 to 2000 are
presented in Figure E-10.


E-11












SAMPLE INPUT FOR MIDTOWN BEACHNNOURISHMENT PROJECT


Midtown Beach Nourishment Project, with groins
NO T co 19 A4 DK Y
1.40 6.4 85.0 90.0 180.0 325.0 86400.0
A* 1 K VFAC.7 qeAF i Ct r 3 I'4X '..
14.9 6.0 1.10 1.29 0.171 1 180 3650
-LSTPSucrC T y V .$TaAC V1 rltfC-e-
85 98.0 86 112.6 87 136.0 88 136.0
90 143.0 91 167.0 92 143.0 93 136.0
95 088 .0" 0 ,'- ry ur "c L .

0.0 0.0 90000. 0.0 49500. 2.0 60000.
90000. 3.0 100000. 3.0 140000. 2.0

81 97

81 97 1 0.998


87.0
175.0
175.0
175.0
175.0
175.0
175.0
175.0
175.0
175.0
175.0
175.0
175.0
175.0
175.0
117.0
58.0


T,) Ao


$4, iAnt-> rei
~Ti"4 J ^V..I Yr
11 1

89 145.0
94 124.0



3.0


For Ntriksie.-t


Figure E-9. Input File for Midtown Beach Nourishment Project



4.4.3 Evolution Prediction of the Manatee County Beach Nourishment Project


Construction of this project included the placement of 2.32 million yd3 over a total project length of
4.2 miles and was completed in April 1993. The project included a 1,500 ft transition at the south end.
Comparisons of measured and calculated total volumes remaining in the project area are presented
in Figure E-11.


E-12


^o Fx fx+re. -L-S A'Ici
[or- Airv4-A-C'a












0.9

0.8 -


S*~ .--.Groin_.Lenaths Increased by 40 Feet
0.6- *



0.4 ... ......... .. .
| .No Groins
| 0.3

0.2
0.1
0.0 3
0.0 ----- -------------
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
Year

Figure E-10. Midtown Beach Nourishment Project. Comparison of Monitoring
Results and Calculations. Demonstrating the Stabilizing Effects of Groins.


0
1990


1995 2000
Years


Figure E- 11. Blind-folded Comparison of Predicted and Measured Performances for Manatee County
Project


E- 13









Figures E-12 and E-13 present comparisons between predicted and measured alongshore distributions
of shoreline changes from pre-construction to February 1995 and pre-construction to February 1999,
respectively. Figures E-14 and E-15 present comparisons between predicted and measured alongshore
distributions of volume densities for the same periods.


Pre-Built-02/1995


9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Monument
Figure E-12. Blind-folded Comparison Between Predicted and
Measured Shoreline Changes for the Manatee County Project,
Pre-Construction to February 1995.


Pre.Buit-02/1999


9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Monument
Figure E-13. Blind-folded Comparison Between Predicted and
Measured Shoreline Changes for the Manatee County Project,
Pre-Construction to February 1999.


E-14











Pre-Built-02/1995


9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Monument
Figure E-14. Blind-folded Comparison Between Predicted and
Measured Volume Changes for the Manatee County Project, Pre-
Construction to February 1995.
Pre-Built-02/1999


e120

100

" 80

? 60

o 40'


9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Monument
Figure E-15. Blind-folded Comparison Between Predicted and
Measured Volume Changes for the Manatee County Project, Pre-
Construction to February 1999.


E-15






























APPENDIX F

A "WHITE PAPER" ON SHORELINE MODELING
Prepared By
Bruce A. Ebersole, Mark B. Gravens, Hans Hanson and Nicholas C, Kraus


F-l














White Paper on Shoreline Modeling


Prepared for

Office of Beaches and Coastal Systems
Department of Environmental Protection
State of Florida

CETAC Workshop No. 2
Monitoring Guidelines and Beach Nourishment Design









Prepared by

Bruce A. Ebersole1, Mark B. Gravens1, Hans Hanson2, and Nicholas C. Kraus1


1U.S. Army Engineer Research and Development Center
Coastal and Hydraulics Laboratory
3909 Halls Ferry Road, Vicksburg, MS 39180-6199

2 Department of Water Resources Engineering
Lund Institute of Technology, University of Lund
Box 118, Lund, Sweden S-221 00





October 20, 2000









Introduction


This paper was prepared to provide experienced-based information and views for
consideration by the workshop participants. Our understanding is that 1 2-days
of the subject 2-day workshop will be dedicated to Beach Nourishment and
Prediction Methodology. We further understand that the focus of this portion of
the workshop will be comparison of prediction methodologies, specifically the
treatment of the background erosion rate1 (BER), calibration, model results, and
ease of application. According to material provided prior to the workshop (Letter
of Dr. Robert G. Dean dated August 3, 2000) the GENESIS model will be
compared with "a very simple model (DNRBS)" which was developed by
Dr. Dean.

Based on this understanding, we have concern about the "ease of application"
premise, the a-priori association of "very simple" with the model DNRBS and use
of "Number of person hours for calibration" as a leading point of comparison. We
believe that the workshop participants should view the comparison of the two
prediction methodologies in the context of larger engineering issues associated
with development of the most reliable modeling result leading to an optimized
project design. The following comments address selected central issues of
modeling for beach fill engineering design.

Model fundamentals and prediction methodology

It should be recognized that the underlying basic theory is the same for the
GENESIS and DNRBS models. The differences being compared in the
workshop are, therefore, differences in methodologies of application and not
differences in principles of model formulation. As such, the GENESIS model
could be applied within the constraints of the proposed simplified methodology
with the same ease of application evidently attributed only to the DNRBS model.
The 1989 GENESIS Technical Reference and other literature clearly discuss
simplified applications, called the "scoping mode," and detailed applications,
called the "design mode."

Although the theory of the models is the same, there is an enormous difference
in the capabilities and generality of the two models, with the DNRBS model
limited to idealized conditions and GENESIS capable of simulating idealized to
complex conditions that change in space and time over the modeling domain.
Examples are discussed below.




1 Also recognized as the historical rate of shoreline change, allowing for the possibility of both
landward and seaward translation of shoreline position, referenced to a common vertical datum.
A given stretch of coast will likely have a long-term rate of change that varies in magnitude and
direction, depending on location. The historical rate of change typically depends on the time
period selected.









Level of effort vs reliability


Apparent from the "Format for Presentation" outline provided by the workshop
organizers, a major point of comparison is the time (person hours) required for
calibration. This point of comparison is biased in favor of the DNRBS model
because, among other issues, the DNRBS calibration methodology amounts to
the enforcement of a user-specified (externally provided) BER that is
implemented as a background transport gradient within the model.
Consequently, the calibration of the DNRBS model rests in great part on a user-
specification and not on determination of time-varying model inputs to replicate
conditions occurring at the project. As such, questions about the BER include
how it was arrived at, its reliability and variability, and the time frame and spatial
extent of its validity. Blind specification of the BER dangerously avoids the
profound question of the causes of the erosion and accretion along the coast.
We recommend that questions on the proposed DNRBS BER methodology such
as the above be raised at the workshop.

More important than level of effort required for model calibration is the reliability
of model predictions. We believe model calibration to replicate long-term
measured shoreline change within the context of an acceptable sediment
transport regime results in a more accurate treatment of the processes and leads
to more reliable results than does calibration by user-specification of a rate of
shoreline change. The process of calibration itself provides the modeler/designer
with insights about the important coastal processes active at the project site.

Treatment of "background erosion"

The workshop organizers have not defined "background erosion" or how it should
be estimated. Is background erosion produced by longshore transport or by
cross-shore transport, or both? Can background erosion be described
adequately by the seven allowable position-erosion rate pairs at all project
domains? What is the appropriate time scale for determining the BER at a point?
What are the limitations of the methodology? How well does the BER replicate
observed shoreline change over the last 10 to 15 years? How does one compute
the BER where the data indicate long periods (10 to 30 years) of shoreline
progradation followed by long periods of shoreline erosion or vice a versa? How
are possible changes in sediment inputs from the boundaries (e.g., bypassing at
inlets, feeder beaches) of the project accounted for?

Ad-hoc transformation vs 2D wave model

The ad-hoc transformation recommended by the workshop organizers involves
simulating the evolution of a beach fill placed on a long straight shoreline and
transferring the predicted shoreline changes to the prototype. This simplification
of procedure enables predictions to be made for coastal reaches with
geomorphic features that may be "straightened out" if the predictions were made








using the arcuate prototype shoreline. We believe a modeling approach that
aims to capture the processes that sustain an arcuate shoreline produces a more
reliable modeling result than does the ad-hoc transformation. Examples include
running a 2D wave model such as STWAVE to define nearshore wave conditions
which act, in nature, to maintain the arcuate shoreline, or simulating the influence
of stable regional contours that control the geomorphology within the project
domain. How is the improved performance that comes with maturation of beach
nourishment projects analyzed within the context of the ad-hoc transformation
technique? Utilization of the ad-hoc transformation technique precludes the
possibility of identifying post-construction hot spots and examining the influence
dredging of nearshore borrow areas may have on incident wave conditions and
associated shoreline change.

Coastal structures, beach fill and boundary conditions

Although the DNRBS model can represent beach fill and groins, it does not allow
for multiple beach nourishments to occur within a given model simulation (as in
life-cycle simulations), and the treatment of groins (and jetties) within the DNRBS
model is simplified (e.g., no groin permeability, no diffraction, no bypassing prior
to groin burial). GENESIS, on the other hand, includes capabilities to simulate
both diffracting and non-diffracting groins, detached breakwaters (with wave
transmission), seawalls, and complex structures (T- and L- groins and jetty
spurs). GENESIS allows for the specification of multiple beach fills each with its
own spatial and temporal characteristics, enabling great flexibility for the
examination of multiple nourishment cycles and the interaction of multiple
projects. GENESIS also allows for the simulation of multiple point or line
sediment sources or sinks with arbitrary spatial and temporal definitions (for
simulating mechanical bypassing, or sediment supply from rivers or streams, or
accounting for losses or gains of sediment by cross-shore processes). GENESIS
is equipped to handle a variety of lateral boundary conditions (pinned-beach,
moving shoreline position, and gated). The DNRBS model allows only a pinned-
beach boundary condition.

Modeling shoreline change for project design and optimization

Although GENESIS can be applied within the context of the (simple) DNRBS
methodology, it always contains all the features of a complete engineering design
tool and is equipped to simulate the influence of a wide variety of coastal
engineering activities and project settings. The DNRBS model and methodology
can analyze only the simplest of projects. Using the DNRBS model and
methodology to simulate the evolution of a rectangular beach fill gives a
sediment budget in which the net transport equals the gross transport at all
calculation cells. Unlike GENESIS, the DNRBS model is unable to simulate the
interaction of multiple project features (seawalls, structures, beach fill transitions,
natural sediment bypassing, mechanical bypassing operations, etc.) or to









quantify the performance differences between project alternatives that may
include one or more of the project features previously listed.

There is an investment of time required for the development of a calibrated
GENESIS model for a given project study area. However, the return on that
investment by way of analysis capabilities we believe outweighs the limitations of
adopting the DNRBS model and methodology. In addition, GENESIS may be
applied using a layered approach, starting with a DNRBS-compatible scoping
mode application and then gradually and, as necessary, including more complex
features and methodologies. There is automatic upward compatibility and room
for growth to more complexity in project design.

Recognizing differing scales of projects we acknowledge that the DNRBS model
and methodology may be appropriate for some projects (fill placed on a long and
straight shoreline with no seawalls, for example). However, if the project
represents a significant investment of public resources we believe the
engineering analysis should be performed utilizing a reliable modeling tool and
methodologies for which various alternatives can be realistically described.

Future developments in shoreline change modeling

The US Army Corps of Engineers continues to invest in the development of
GENESIS and associated tools. Model capabilities currently being worked on
include representation of transport by tidal and wind-generated currents, and
formation of tombolos at detached breakwaters and T-head groins. GENESIS
(together with STWAVE and numerous related analysis and visualization tools,
including 2D grid generation) has been integrated into a modern Windows-based
modeling system known as NEMOS (Nearshore Evolution Modeling System).
Veri-Tech Inc (a Cooperative Research and Development partner with the US
Army Engineer Research and Development Center) markets the NEMOS
software as a computational module within the Coastal Engineering Design and
Analysis System (CEDAS). The Corps will host a training workshop on the
application of NEMOS software prior to and in association with the 13" Annual
National Conference on Beach Preservation Technology (February 6-7, 2001).
The workshop will give the coastal consulting industry and academic
communities the opportunity to hear about on-going R&D for GENESIS and the
operation of the NEMOS interface, as well as to provide feedback for
improvement of the NEMOS software. We welcome your comments on how to
improve GENESIS and its associated toolboxes and models.



























APPENDIX G

RESULTS OF WORKING GROUP 1

"Role of Modeling in Beach Nourishment Design"

Prepared by:

Chris Creed, Mark Gravens, Michael Poff, Bob Brantly
and Mark Leadon (Chairman)


G-1









CETAC Workshop # 2
(October 24-26, 2000)
Presentation by Working Group 1

Discussion Topics
I. Role Of Simple and Complex Models in Beach Design
II. Needs for Model Development
III. Needs for Model Data Accuracy

Group Members
Mark Leadon, Chris Creed, Mark Gravens, Michael Poff, Bob Brantly

Discussion Summary
I. Role Of Simple (Idealized) and Complex (Generalized) Models in
Beach Design

General Role (of both types):
Develop understanding of site specific coastal processes
Predict overall project performance
Predict localized project performance
Predict potential adverse project impacts (ie, downdrift erosion)
Assist in educating the public about project expectations (including
ability to provide simple graphical depictions of expected project
performance)

General Comment: Use of any model should be dependent on site-
specific project/site elements, such as;
Economic constraints
Environmental constraints
Complexity of beach & nearshore areas
Project components
beach fill only
structures (groins, breakwaters)
seawalls
inlet affects
bypassing
etc.








Note: Some members of the group suggested substituting the words simple
and complex with "idealized" and "generalized", respectively.
Some specific model roles:

Simple/Idealized

Develop order-of-magnitude volumetric requirement
Provide estimation/verification of gross transport/shoreline
change rates (cross check for complex/generalized models)
Tool for preliminary project evaluation (ie, budget, project
life, etc.)

Complex/Generalized

Design & design optimization
Provides a tool to demonstrate and assist in improving
understanding of coastal processes & morphological
changes
Assists in identification of hot spots
Evaluation of benefits/impacts of project features
(ie, complex bathymetry, structures, bypassing, sand sinks)

Comment: It was noted by group members that complex models can
be set up and run in a simplified manner and, conversely, that simple
models may be used to provide insight into some of the items listed
under "Complex/Generalized" above.

II. Needs for Model Development

Integration of cross-shore & longshore models/model results
(including storm response)
Incorporation of possible performance variability (statistics)
Improving representation of boundary conditions, model inputs,
project features (ie, structures, reefs, etc.)
Generalize sediment transport relationship to include processes
other than breaking waves (ie, tide-driven currents, wind, etc.)

Additional input/comments during presentation:
Bob Dean 1) Need capability to represent profile response in cases
of mixed sediments, 2) In cases where projects do not perform to








expectations, a focused effort should be developed to identify and
document causess.
Emmett Foster Consider and develop alternative methods for
calibrating models.

III. Needs for Model Data Organization

Standardization of formats for input and output
Inventory of existing project model results and monitoring data,
and model prediction vs. monitoring performance analyses
Develop database of project design components and model vs.
monitoring results with standardized project fact sheets and
comparative analyses results including standardized shoreline and
volumetric change graphics.

Fact sheets should include (w/attachments) the following:
Summary of project including design components,etc.
Design predictions
Project performance
Monitoring data/analyses

Organize information into documented summary and provide
information through accessible medium (ie, internet)


Additional Point: Model calibration/verification intervals should be of
sufficient duration that they represent reasonable approximation of the
historical change and expected future without-project shoreline change.


























APPENDIX H

RESULTS OF WORKING GROUP 2

"Monitoring Issues"

Prepared by:

Gary Anderson, Kevin Bodge, Chuck Dill, Cynthia Perez,
Linda Lillicrop and Echo Gates (Chair)


H-1













MONITORING ISSUES


Working Group Participants
Gary Anderson
Kevin Bodge
Chuck Dill
Echo Gates
Linda Lllycrop
Cynthia Perez

PROBLEM STATEMENT:

The Department at present requires project monitoring through the Joint Coast Permit (JCP)
where non-compliance with timely data collection and reporting is difficult to enforce.
Regulators have no rule to reference when compliance with monitoring requirements in a permit
is not met by project sponsors and their contractors. By shifting monitoring requirements to the
project agreements the Department enters into with local governments, the task then comes
through staff review through the scope of work submitted before initiation of work and
enforcement of the requirement becomes possible through contractual obligation.

If project monitoring is to be successful, standardization of practices should be established and
communicated to sponsor, engineers, surveyors and others interested in the monitoring process.
The working group was charged with providing recommendations to the Department on project
performance monitoring and graphic representations of the collected data. Recommendations
from the group will provide input to the QA/QC+ Plan for use in project quality assurance and
control at the contract/project agreement level. The plan is presently under development by
Engineering Staff of the Beach Management Section of the Office of Beaches and Coastal
Systems.

RECOMMENDATION FOR SPECIFICATION:

Topographic and Bathymetric

* Annual surveys 1 month.

* Define acceptable accuracy and let the market/situation determine method of data collection.

* Survey to depth of closure + additional 10% of the profile to capture bathymetry for extreme
events.

* Survey to monument + 50' landward (minimum); further landward for profiles vulnerable to
erosion or inundation.

* Profile data to be collected at every monument depending on site.

* Extend surveys up/downdrift until out of expected project influence.


H-2












* Establish level of confidence/accurancy of profiling with minimum of 3 repeats at every 10t
line or as appropriate to the situation.

" Off/onshore surveys completed within 10 days of each other.

Sediment

* Pre-construction grab samples from a minimum of five sites: dune, berm, intertidal zone, bar,
and offshore. Quantity, storage methods, archive site are to be determined.

" Post-construction grab samples similar to pre-construction.

* One sample similar to pre-construction between nourishment cycles.

* Characterize all native beaches statewide.

* Archive materials and analysis of statewide characterization of native beaches in a single
repository and maintain in perpetuity.

" Describe date of collection and location by county and nearest R-monument for each sample.

Reporting

* Reports should include all data, and subsequent interpretation.

* Provide all data in digital format; and print a hard-copy of all profile and sediment grain size
data in appendix, noting, dates, datum, etc.

* Report should include an after-action assessment stating why performance conformed to or
departed from design.

Graphics

* Include explanatory data on each graph; including, as appropriate,
a. Project and county name
b. Range or locations of R-monuments described by data
c. Depth to which volume calculation is made
d. Elevations (with datum) of depicted shoreline or contour data
e. Date or elapsed time to which data apply
f. Date ofbathymetric survey
g. Date of topographic survey
h. Name of contractor

* Where color is used to differentiate data, also use distinguishing line types or symbols foi
clarity in photocopies.


H-3













S iiaximum oTfour survey rates per graphic; maximum of three is preferred.

* Pre-project prediction curves can be depicted as a reasonably tight ange in those instances
where performance is highly uncertain.

* These are minimum recommended guidelines; investigator is encouraged to prepare
additional graphics and analysis that further describe project specific performance.

Examples:

Each of the following types of performance graphics should be prepared for each report an
project, in addition to other graphics and analysis that might further illustrate specific project
performance.

Beach Profiles


Include at all measured R-monuments, as an appendix if needed.
Vertical exaggeration preferably 5:1 but less than 15:1.
Limit to a maximum of four dates per plot.
Add vertical and horizontal grid lines.
Show full profile length. Preferable to also depict "blow-up" of profile data at beachface
(dune to -6') where profiles are long and changes in shoreface difficult to see.


Volume performance



ci
c(
C.
E

E


Time (months post-construction)


Volume vs. time (a.k.a. cumulative volume change vs. time)
* Show for total volume above closure (specify depth) for total project length, or sub-reaches
of length where performance or objectives vary alongshore.
" Depict for total volume above specified upper beach contour (ex., MHW, NGVD, MLW, etc)
* Display the design prediction in all graphs.


H-4


i.













Shorlinr e aiid-anform Areaa Performance


Initial post-equilibrium
S' ,. prediction or design value
0 -. pecify)
---------- -;-----s^- .-* ..._... 100%
0 100




1- e---- Actual
< t--* Predicted
0
Time (months post-construction)

Depict as total planform change or reach-averaged beach width change, versus time.
SDepict at a specified contour elevation with datum noted.
* Include design predictions, including minimum design value and or initial predicted
equilibrium adjustment value.

Combined Volume Width (or Planform) Depiction

100%

r-




u- Total Volume above Closure 4------
SPlanform (or Average Width) *--

0%
Time (months post-construction)

Comparative temporal change of volume and berm width, relative to post-construction values of
100%, depicts equilibration process. (For example, a more rapid percentage decline in the post-
construction beach width or planform area, relative to the total measured change in beach
volume, suggests cross-shore equilibration of the fill.)


H-5















Alongshore Variation


Post Equilibrium Advance Fill

------- Design Berm
--------- Measured Shoreline or Volume


C'r"


Shoreline Map


Show this graph for beach width (MHW, or referenced to 0' NGVD, etc.) and for total volume
alongshore (cy/ft).

Path: G:\CETAC\WorkshopsilO-24-OOMonitorRecommendations.doc


H-6


L-
0

-CS

E
.2




























APPENDIX I

RESULTS OF WORKING GROUP 3

"Design Accuracy Assessment and Calibration Methods"
Prepared by:
Emmett Foster, Mark Leadon, Karen Erickson, Brett Moore,
and Tom Campbell (Chairman)





















I-1








APPENDIX I
RESULTS OF WORKING GROUP 3
"Design Accuracy Assessment and Calibration Methods"
Working Group Participants
Emmett Foster, Karyn Erickson, Brett Moore,
and Tom Campbell (Chairman)


INTRODUCTION

There are a number of projects that appear to be performing differently than designed; some of these
projects have needed more nourishment sooner than expected creating a public perception of failure.
Others have performed better than expected on average but have experienced the formation of hot
spots that require early attention and the appearance of at least partial failure. The committee
discussed the scope of these problems and how the design process could be modified to address these
concerns.

EXAMPLES AND CAUSES OF PROJECT PERFORMANCE PROBLEMS

Martin County Beach Nourishment: Requires renourishment in 4 years rather than 11 as designed.
The beach is less than half of the design width and surveys suggest that more than 2/3 of the placed
material has eroded away.

Longboat Key 1993: Construction provided an average beach of only 50 ft instead of the 70 ft design
and the mid key beach protecting the coastal road was only 25 ft wide after two years.

Anna Maria Island: Beach nourishment experienced an offshore movement of sand 30% higher than
expected resulting in narrower than design beaches; compensating design procedures allowed for
placement of additional sand that improved public perception of performance based on visual
observation.

Captiva Island 1998/1999: Beach nourishment experienced two hot spots that lost most of their fill
in 7 years even though the average losses were lower than expected.

Ocean Ridge 1998: Beach nourishment is eroding faster than predicted with the southern 1/3 of the
project needing nourishment after only 2 years. The total remaining project volume is close to the
expected design range however because of extra fill that the contractor placed outside the design
template.

Jupiter Island 1974-1982: Projects lost all dry beaches in less than 3 years as finer sands moved
offshore.

Delray Beach, Longboat Key, Captiva Island: Projects have required nourishment volumes 2-5 times
the volume that would be predicted by the historic erosion rate of those beaches.










The major reasons for performance problems are:


1. Cross-shore equilibration greater than expected
2. End losses greater than expected
3. Hot spot erosion

DISCUSSION

1. Cross-Shore Design

Cross-shore designs have been based on creating a beach that takes similar offshore slopes to the
native beach. Early designs used a two-slope method and later designs use a profile translation
method, which is more accurate. Grain size differences are accounted for by overfill or equilibrium
profile adjustments; the latter having more basis in scientific design. The accuracy of the dry beach
prediction is largely based on how close the offshore profile shape can be predicted.

The most accurate way to account for offshore movement of placed fill is to assume that the
nourished profile at equilibrium will be similar to the prenourished beach profile with adjustments
expected for grain size differences between the native and the nourished beach. Additional
adjustments may be expected if the native beach was artificially steepened by structures, which will
not be affecting the nourished beach; in those cases more sand will move offshore once the beach is
nourished. Designers still use an array of design methods to develop their cross-shore design, which
can lead to problems. It would be helpful if the design standard were developed by the state.

Reviewers can look for the depth that the equilibrated profile intercepts the native profile; if that
depth is above the depth of closure than the project is probably under designed. It should be noted that
the largest errors are possible when the native and nourished sand are computed to be exactly equal
because a small difference in actual grain size would result in big differences in cross shore
performance.

Even when a coarse grained material computes to provide a large fill savings because of shallow
intercepting profiles it may be appropriate to consider only a portion of those savings because the post
nourishment active profile will include the seaward portion of the native beach which has the finer
sands.

2. End Losses

Early Florida beach nourishments considered only background erosion rates to estimate long-term
nourishment needs of a project, which in all cases has led to significant underestimates of long-term
nourishment needs. One reason for the underestimate was the lack of consideration of end losses due
to the spreading or diffusion of the sand to the adjacent beaches. ( the other reason was the need to
feed hot spots)








More recent design practice includes estimates of end losses. In many cases however the end losses
are still underestimated leading to under design of the project. In some cases the underestimates are
caused by reliance on the GENESIS model results, which often shows little or no end losses (because
of calibration problems we suspect). In other cases a token amount of end loss (say 10, 000-15,000
cy/yr) is included to show that it was considered to project reviewers. In some cases it was stated that
the overfill calculation somehow included the end loss which it doesn't.

Project reviewers should expect that on east coast projects, unconstrained nourishments with 8-year
renourishment intervals would have end losses in the range of 50,000 -75,000 cubic yards per year
depending on their length and re-nourishment interval. On West coast projects the end losses will be
in the range of 25,000 -50,000 cubic yards per year. If projects were constrained at one end than end
losses would be half of the stated amounts. End losses should be added to background erosion rates
(and hot spot erosion) to estimate nourishment needs.

3. Hot Spot Erosion

All projects erode at different rates along their length; some project segments actually accrete.
Nourished projects often develop hot spot areas that erode much faster than the average erosion rate
of the project. This differential erosion rate creates a need for placement of additional fill in the
project above the net erosion that the project experiences. This is why constrained project fills like
Captiva Island and Longboat Key are being nourished at 2-3 times the net rate of erosion of the island
and the reason why Delray Beach now contains more than twice the initial fill placed in 1973 after
four nourishments.

The renourishment rate of a project should include the consideration that there will be differential
erosion along the project length, which will require renourishment volumes greater than the net loss
of sand. Designers almost never consider this when they first design the beach, which makes any
review of long-term nourishment projections look bad. Long projects suffer the most from this
underestimate since there are more opportunities for differential erosion. For example the 18 mile
long Panama City beach project had a long-term average net erosion rate of only 30,000 cy/yr, which
suggests that the project would need to be renourished with only 150,000 every 5 years. Considering
that we placed 9,000,000 cubic yards of sand and the project is experiencing normal levels of
differential erosion the early estimates of renourishment are in the range of 1,000,000 cy almost 7
times the net rate of erosion.

This is a new area for designers but it is not trivial and, if neglected, will unfavorably reflect the
State's program. If hot spots are treated with structures, gross erosion can be brought closer to net
erosion rates. However structures should only be used if they are cost beneficial or if sand is in
limited supply. It is suggest that an amount of fill equal to 5-10,000cy /mile/yr be added to
nourishment estimates to account for hot spot erosion.




























APPENDIX J

Material Provided for Case Study 1

MANATEE COUNTY BEACH NOURISHMENT PROJECT













U.S. ARMY CORPS OF ENGINEERS


FLORIDA DEPARTMENT OF ENVIRONMENTAL PROTECTION
OFFICE OF BEACHES AND COASTAL SYSTEMS

Coastal Engineering Technical Advisory Committee
Workshop 2

BEACH NOURISHMENT DESIGN AND PREDICTION METHODOLOGY: CASE STUDY


I. GENERAL PROJECT CHARACTERISTICS

(a) Project Name:

(b) When Designed:

(c) Project Setting (DEP Monuments, County):

(d) Numerical Model Used:

(e) Project Length [miles]:

(f) Project Volume [cubic yards]:

(g) Project Cost:

(h) Distribution of Nourishment Volume Density:

(i) Borrow Area Location and Characteristics:

(j) Native Sand Size Characteristics:

(k)

(I) Nourishment Sand Size Characteristics:


(m) Additional Relevant Project Features:

(n) Has Project Been Constructed?:

(o) Are Monitoring Data Available?:

(p) If Answer to (o) is Yes, Please Describe:


Manatee County, Florida, Shore Protection Project

1988-1991

Manatee County, FDEP Monuments R-12 to R-33.3

GENESIS

4.2

2,153,000 (5/91, GDM): 2,324,000 (3/93, As-Built)

$8,574,000 $3.69 per cy

97 cubic yard per foot of shoreline

Adjacent to project south end in depths of 15-20' (MLW).

D50 = 0.36mm (Less Shell D50 = 0.17mm)



D50 = 0.30mm (Less Shell D50 = 0.12mm)
Overfill Ratio = 1.20, Renourishment Ratio = 1.20

Taper at south end of project is 0.5 mile long.


Yes

Yes

Beach Profile Surveys:
Dec-92
Feb-93
Mar-98


JACKSONVILLE DISTRICT















U.S. ARMY CORPS OF ENGINEERS


FLORIDA DEPARTMENT OF ENVIRONMENTAL PROTECTION
OFFICE OF BEACHES AND COASTAL SYSTEMS

Coastal Engineering Technical Advisory Committee
Workshop 2

BEACH NOURISHMENT DESIGN AND PREDICTION METHODOLOGY: CASE STUDY


II. CALIBRATION EFFORTS AND RESULTS (Based on Previous Work)

(a) Special Efforts Required in Calibration: Recession rate of 2.3 ft/yr had to be imposed.

(b) Results (Calibration Error [ft]): 9.1

(c) Person Hours Required for Calibration Effort: 80

(d) Coefficients Used in GENESIS Calibration: K1 = 0.2


(e) Values in Design for:


III. APPLICATION OF SIMPLE METHOD

(a) Person Hours Required for Calibration Effort:


K2 = 0.2

Depth of Closure, h* [ft] = 20.2
Berm Height, B [ft] = 5.0
Total 25.2


(b) Coefficient Use in Calibration: K =

(c) Values in Design for: Depth of Closure, h* [ft] =
Berm Height, B [ft] =

IV. COMPARISON OF RESULTS FROM TWO METHODS

(a) Present, in Graphical Form, the Predicted Total Volume Remaining Within the Project Area,
versus Time for the Two Methods.

(b) Present, in Graphical Form, the Predicted Longshore Distribution of Volume Density for
Various Times for the Two Methods.

(c) If Monitoring Data for the Completed Project are Available, Present and Compare in
Graphical Forms, the Measured Volumes Remaining Within the Project Area for the Available
Times and the Predicted Volumes Remaining Within the Project Area, for the Available Times
and for the Two Methods.

(d) If Monitoring Data for the Completed Project are Available, Present and Compare in
Graphical Forms, the Longshore Distribution of Measured Volume Density for the Available
Times and the Longshore Distributions of Predicted Volume Densities for the Available Times
and for the Two Methods.


JACKSONVILLE DISTRICT
























prcsente.y;
ThompS-P. Srnith; RE.



















Lcc;O Agreci-nent:
ZiMe'llchilunill q)jprov.,d by highor

condu!(.t' and Dl;Iqll


Sponsor completed Limited
ReevalUation Report (LRR)
in 2000 for renourishment in 2001.




J I
Aloll(acc Colill.11,




































J-5




























.- . ---





I Berm Helqh1 Eft S.O.__
to.ai ___
APPLI MREMET40
____'L_-_.I ________ -


4;'#

-0.
~'

4' *c iLL


I


Un




















,,. ;L': n.s /mU ON/./.2/Fi.E- . .
A H X: RIM.S6/SIIMUjLATIOI1a.28",.2./TILL/IECSS ION


- INIT. SHORELINE
-+--**+ CALCUIATED
----- DIFF. GROIN
- 83I--* SAALL
-- BEACH FILL
-- DESIGN SHORELINE


18 12 14 16 18 2 22 24
ALONGSHORE COORDINATES
r :* ,''. l i ; "1 1 .


26 28


38


+I

S
S


A N : lUN.S39/SIUITlON/T[B.2a/.2/rFLL/RED.CRt/REC-.B-38-1996' I

18-0
.- 4 INIT. SHORELINE
+*4---+ CALCULATED
9-- DIFF. GROIN
S..... ----- SC ACAL
am- +*,~.. .- DESIGN SHORELINE


' 7.--- \ ..o>%
.... .......... i '


SWT

4881 ---'----- Iit--I I-I-l
i 12 14 16 18 28 22 24 26 28 38
ALOKCSHORE COORDINATES


~ ~ ~ ~ ~ ~ *^ '' .


. .., ,I































































J-8































































J-9



























































J-10



























































~1.~ !


U


BIdFo ded onprisonof Prded ced and Ma ua
Parom Incesfor MiteeCintyPWPjec


J-11


;
1 .(
k
c'~ .o.;



















MANATEE COUNTY SHORE PROTiECT N PROJECT
Fill Remaining In Project Area: Measured and Predicted


0 20 40 60
Tin[n[months]


80 '100 120


"" ." ....... ...


... ..... .........., -



140 1 1


mBlfoled Cdmalkn ol Suaiel Podtlon
for Mantlee County Project 5.8 Y s Al Ntourishment


















J-12


--- -- I


I;-
i



























IPROL UM& -1. LOWAO~MW. A 4A W. 60-1MI0I FDiOPM-U
ii'i
~71
..............i i -


J-13































APPENDIX K

Material Provided for Case Study 2

MARTIN COUNTY BEACH NOURISHMENT PROJECT


K-l















MODELING EFFORTS
AND
RESULTS


Shorelines fitted at expense of'histoiel ltrans~otk8ats
* Calibration Error
: 25 feet
* Person Hours Req'd for Calibration
176 hours (estimated)























































':,,@ N I


K-3


I"., 'f:
















- Recommended Length 3.75 miles
- Dune Restoration 20' wide, +13.6' mlw, 1:5 slope
- Beach Berm 35' wide, +9.1 mlw, 1:8.5 &1:20 slopes
- Renourishment Interval -11 years
- Overall, Ratio -1. i,- &. -


Commenced Dec 95


K-4















March 1996
- Storm of the Century hits
during construction

Winter 1996
- Continuous northeasters

February 1998
- Northeaster


* Beach Profile Surveys
Pre- & Post-fill ('92, '94, 5/95, 11/95, 6/96, 12/96, '97, '98, '99,'00)
Post-storm (4/96, 12/96, 11/99, 12/99)
* Aerials Photography
B&W, controlled digital images ('92, '96, '97, '98, '99)
* Sand Samples
4 stations along 8 profiles p7,.a


K-5

















Post-fill +105 ft
8 months Post-fill -44 ft
1st Year Post-fill -54 ft
4th Year Post-fill -65 ft
* Volume Changes


PROJECT STATUS


* Renourishment
wahain iil i 'iv


K-6


1~~ 1~1~_1111.1 1~1 --. ;.i--.-- --.. I-













I -. : J


MODELING EFFORTS
AND
RESULTS


Shorelines fitted at expense dffltsi'M eal- tanrot'
* Calibration Error
j 25 feet
* Person Hours Req'd for Calibration
176 hours (estimated)
G C^J;alib flCCrdeMinsotasm















































I.--- ProjeCL Area ----~











- measured i


k+---- Project rea/-


1,..
A.-l ----- --
.10.0


.11.0


/N vv 'AV, YI IV


Legend
S Measured
Predicted






































































o2-0 .--,-., .--.-- ---- ... .. ------.-------

S .2
.... .. ... ......... .. ... . .. .. .. .. .. ... .. ... ........ ..... . .










0 .
| . .. . ...... ..... .. ..... ... ........ ........ .... .... .......... ... .. .. .. .
O -- ----I I------ ------ .... ----....




00
1995 1996 097 1998 1999 2000 001 2002 2003 2004 2 05
Years

Predicted Perfonrance for Martin County Be ich Nour shnent Pro oct









K-10



































K-11


i nank You






























APPENDIX L

Material Provided for Case Study 3

CAPTIVA ISLAND BEACH NOURISHMENT PROJECT




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