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Coastal Sediment Budget for Jupiter Inlet, Florida

HIDE
 Title Page
 Acknowledgement
 Table of Contents
 List of Tables
 List of Figures
 Abstract
 Introduction
 Site description and database
 Shoreline and beach volume...
 Sediment budget
 Summary and conclusions
 Appendices
 References
 Biographical sketch
 

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COASTAL SEDIMENT BUDGET FOR JUPITER INLET, FLORIDA By KRISTEN MARIE ODRONIEC A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLOR IDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2006

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ii ACKNOWLEDGMENTS I greatly thank my supervisory committee, Dr. Ashish Mehta, Dr. Robert Dean, and Dr. Andrew Kennedy, for their assistance, guida nce and insight througho ut this research project. I would also like to express my gratitude to the Jupiter Inlet District for providing the financial resources needed to ca rry out this project. Thanks also go to Michael Grella of the Jupiter Inlet District for always providing prompt answers to my many questions and requests for information. I would also like to thank all of my fello w coastal engineering students and friends, whose support and distraction kept me sane. Finally, my ultimate thanks go to my family who were always there for me providing patience, understanding, encouragement and love.

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iii TABLE OF CONTENTS page ACKNOWLEDGMENTS..................................................................................................ii LIST OF TABLES.............................................................................................................vi LIST OF FIGURES..........................................................................................................vii ABSTRACT....................................................................................................................... xi CHAPTER 1 INTRODUCTION........................................................................................................1 1.1 Problem Statement.............................................................................................1 1.2 Objective and Tasks...........................................................................................1 1.3 Outline of Chapters............................................................................................2 2 SITE DESCRIPTION AND DATABASE...................................................................3 2.1 Site Description and Recent History.......................................................................3 2.1.1 Site Description............................................................................................3 2.1.2 Recent History..............................................................................................4 2.3 Beach Profile Data..................................................................................................7 2.4 Ebb Shoal Volume Data.........................................................................................9 2.5 Dredging Data.........................................................................................................9 2.6 Beach Nourishment Data......................................................................................10 2.6.1 Downdrift Beach Nourishment Volumes...................................................10 2.6.2 Updrift Beach Nourishment Volumes........................................................14 3 SHORELINE AND BEACH VOLUME CHANGES................................................15 3.1 Shoreline and Beach Volume Change Calculation Methods................................15 3.2 Data Limitations and Uncertainties......................................................................16 3.2.1 Data Uncertainties......................................................................................17 3.2.2 Corrections for Non-Closure of Profiles....................................................18 3.2.3 Corrections for Monument Relocation.......................................................19 3.3 FDEP Intersurvey Interval: 1974-1986...............................................................19 3.3.1 Shoreline Changes......................................................................................20 3.3.2 Sediment Volume Changes........................................................................20

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iv 3.4 FDEP Intersurvey Interval: 1986-2002...............................................................21 3.4.1 Shoreline Changes......................................................................................21 3.4.2 Sediment Volume Changes........................................................................22 3.5 FDEP Intersurvey Combined Interval: 1974-2002..............................................23 3.5.1 Shoreline Changes......................................................................................23 3.5.2 Sediment Volume Changes........................................................................24 3.6 Volume Change Sensitivity to Depth of Closure.................................................27 3.6.1 Volume Change Sensitivity to De pth of Closure: 1974 to 1986...............28 3.6.2 Volume Change Sensitivity to De pth of Closure: 1986 to 2002...............29 3.6.3 Volume Change Sensitivity to De pth of Closure: 1974 to 2002...............30 3.7 JID Intersurvey Interval: 1995-1996...................................................................31 3.7.1 Shoreline Changes......................................................................................32 3.7.2 Sediment Volume Changes........................................................................32 3.8 JID Intersurvey Interval: 1996-1997...................................................................32 3.8.1 Shoreline Changes......................................................................................32 3.8.2 Sediment Volume Changes........................................................................33 3.9 JID Intersurvey Combined Interval: 1995-2004..................................................33 3.9.1 Shoreline Changes......................................................................................33 3.9.2 Sediment Volume Changes........................................................................33 3.10 JID Intersurvey Interval: 2001-2002.................................................................34 3.10.1 Shoreline Changes....................................................................................34 3.10.2 Sediment Volume Changes......................................................................34 4 SEDIMENT BUDGET...............................................................................................39 4.1 Sediment Budget Methodology............................................................................39 4.1.1 Sediment Budget Equation.........................................................................39 4.1.2 Method for Evaluating Sediment Budget...................................................44 4.1.3 Effect of Length of Beach on Sediment Budget Calculations....................49 4.2 FDEP Sediment Budget Components...................................................................50 4.3 JID Sediment Budget Components.......................................................................52 4.4 Sediment Budget Results......................................................................................52 5 SUMMARY AND CONCLUSIONS.........................................................................54 5.1 Summary...............................................................................................................54 5.2 Conclusions...........................................................................................................55 5.3 Recommendations for Further Work....................................................................57 APPENDIX A FDEP LONG BEACH PROFILES FOR MARTIN AND PALM BEACH COUNTIES.................................................................................................................58 B JID BEACH PROFILES FOR PALM BEACH COUNTY.......................................75 C STORMS NEAR JUPITER INLET, FLORIDA........................................................82

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v LIST OF REFERENCES...................................................................................................83 BIOGRAPHICAL SKETCH.............................................................................................85

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vi LIST OF TABLES Table page 2-1 Beach profile data for Martin and Palm Beach Counties...........................................8 2-2 Jupiter Inlet ebb shoal volu mes (Source: Dombrowski, 1994).................................9 2-3 Jupiter Inlet and interior sand trap dredging volumes..............................................10 2-4 Jupiter Inlet downdrift beach nourishment volumes................................................12 2-5 Jupiter Inlet updrift beach nourishment volumes.....................................................14 4-1 Annual mean sand volumetric transport ra tes in the eastern z one (Source: Patra & Mehta, 2004, p. 11)..............................................................................................43 4-2 FDEP sediment budget co mponents for long analysis.............................................51 4-3 FDEP sediment budget com ponents for short analysis............................................52 4-4 JID sediment budget components............................................................................52 4-5 Short FDEP and JID sediment budget results..........................................................53 C-1 Storms occurring within 150 km of Jupiter Inlet.....................................................82

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vii LIST OF FIGURES Figure page 2-1 Jupiter Inlet connecting the Loxahatc hee River forks to the Atlantic Ocean.............3 2-2 FDEP range monuments north and south of Jupiter Inlet..........................................5 2-3 Area map of Jupiter Inlet............................................................................................6 2-4 Photograph of Jupiter Inlet showing jetties and approximate location of sand trap........................................................................................................................... ...6 2-5 Jupiter Inlet Management Plan reco mmended increase in nourishment beach length........................................................................................................................1 3 2-6 Sand trap and Intracoastal Waterway deposition basin from which sediment is dredged to be used as nourishment..........................................................................13 3-1 Schematic diagram defining depth of closure, where all offshore profiles converge to a certain depth.......................................................................................18 3-2 Shoreline change rate s for the period from 1976 to 1982 in Martin County and from 1974 to 1990 in Palm Beach County...............................................................24 3-3 Unit volume change rates for the pe riod from 1976 to 1982 in Martin County and from 1974 to 1990 in Palm Beach County........................................................25 3-4 Shoreline change rate s for the period from 1982 to 2002 in Martin County and from 1990 to 2001 in Palm Beach County...............................................................25 3-5 Unit volume change rates for the pe riod from 1982 to 2002 in Martin County and from 1990 to 2001 in Palm Beach County........................................................26 3-6 Shoreline change rates for the co mbined period from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County...........................................26 3-7 Unit volume change rates for the comb ined period from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County...........................................27 3-8 Unit volume change rates calculated w ith varying depths of closure for the period from 1976 to 1982 in Martin County and from 1974 to 1990 in Palm Beach County...........................................................................................................29

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viii 3-9 Unit volume change rates calculated w ith varying depths of closure for the period from 1982 to 2002 in Martin County and from 1990 to 2001 in Palm Beach County...........................................................................................................30 3-10 Unit volume change rates calculated w ith varying depths of closure for the combined period from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County..................................................................................................31 3-11 Shoreline change rates for the period from 1995 to 1996 just south of Jupiter Inlet in Palm Beach County.....................................................................................35 3-12 Unit volume change rates for the period from 1995 to 1996 just south of Jupiter Inlet in Palm Beach County.....................................................................................35 3-13 Shoreline change rates for the period from 1996 to 1997 just south of Jupiter Inlet in Palm Beach County.....................................................................................36 3-14 Unit volume change rates for the period from 1996 to 1997 just south of Jupiter Inlet in Palm Beach County.....................................................................................36 3-15 Shoreline change rates for the comb ined period from 1995 to 2004 just south of Jupiter Inlet in Palm Beach County..........................................................................37 3-16 Unit volume change rates for the comb ined period from 1995 to 2004 just south of Jupiter Inlet in Palm Beach County.....................................................................37 3-17 Shoreline change rates for the period from 2001 to 2002 in Palm Beach County...38 3-18 Unit volume change rates for the pe riod from 2001 to 2002 in Palm Beach County......................................................................................................................38 4-1 Definition diagram displaying Jupiter In let along with all possible components in the sediment budget equation...............................................................................42 4-2 Sediment budget components specific to Jupiter Inlet.............................................44 4-3 Plot showing measurements of Jupite r Inlet’s ebb delta volumes, highlighting the three that were chosen to construct a best-fit line..............................................47 4-4 Jupiter Inlet ebb tidal shoal depth contours for the year 2000.................................48 4-5 Jupiter Inlet ebb tidal shoal depth contours for the year 2001.................................48 4-6 Jupiter Inlet ebb tidal shoal differenc e in depth contours (2001-2000) used for volume calculations..................................................................................................49 A-1 Profiles for Monument R-75 in Martin County.......................................................58 A-2 Profiles for Monument R-78 in Martin County.......................................................59

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ix A-3 Profiles for Monument R-81 in Martin County.......................................................59 A-4 Profiles for Monument R-84 in Martin County.......................................................60 A-5 Profiles for Monument R-87 in Martin County.......................................................60 A-6 Profiles for Monument R-90 in Martin County.......................................................61 A-7 Profiles for Monument R-93 in Martin County.......................................................61 A-8 Profiles for Monument R-96 in Martin County.......................................................62 A-9 Profiles for Monument R-99 in Martin County.......................................................62 A-10 Profiles for Monument R-102 in Martin County.....................................................63 A-11 Profiles for Monument R-105 in Martin County.....................................................63 A-12 Profiles for Monument R-108 in Martin County.....................................................64 A-13 Profiles for Monument R-111 in Martin County.....................................................64 A-14 Profiles for Monument R-114 in Martin County.....................................................65 A-15 Profiles for Monument R-117 in Martin County.....................................................65 A-16 Profiles for Monument R-120 in Martin County.....................................................66 A-17 Profiles for Monument R-123 in Martin County.....................................................66 A-18 Profiles for Monument R-126 in Martin County.....................................................67 A-19 Profiles for Monument R-1 in Palm Beach County.................................................67 A-20 Profiles for Monument R-3 in Palm Beach County.................................................68 A-21 Profiles for Monument R-6 in Palm Beach County.................................................68 A-22 Profiles for Monument R-9 in Palm Beach County.................................................69 A-23 Profiles for Monument R12 in Palm Beach County...............................................69 A-24 Profiles for Monument R15 in Palm Beach County...............................................70 A-25 Profiles for Monument R18 in Palm Beach County...............................................70 A-26 Profiles for Monument R21 in Palm Beach County...............................................71 A-27 Profiles for Monument R24 in Palm Beach County...............................................71

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x A-28 Profiles for Monument R27 in Palm Beach County...............................................72 A-29 Profiles for Monument R30 in Palm Beach County...............................................72 A-30 Profiles for Monument R33 in Palm Beach County...............................................73 A-31 Profiles for Monument R36 in Palm Beach County...............................................73 A-32 Profiles for Monument R39 in Palm Beach County...............................................74 B-1 Profiles for Monument R10 in Palm Beach County...............................................75 B-2 Profiles for Monument R11 in Palm Beach County...............................................76 B-3 Profiles for Monument R12 in Palm Beach County...............................................76 B-4 Profiles for Monument R13 in Palm Beach County...............................................77 B-5 Profiles for Monument R14 in Palm Beach County...............................................77 B-6 Profiles for Monument R15 in Palm Beach County...............................................78 B-7 Profiles for Monument R16 in Palm Beach County...............................................78 B-8 Profiles for Monument R17 in Palm Beach County...............................................79 B-9 Profiles for Monument R18 in Palm Beach County...............................................79 B-10 Profiles for Monument R19 in Palm Beach County...............................................80 B-11 Profiles for Monument R20 in Palm Beach County...............................................80 B-12 Profiles for Monument R21 in Palm Beach County...............................................81

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xi Abstract of Thesis Presen ted to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science COASTAL SEDIMENT BUDGET FOR JUPITER INLET, FLORIDA By Kristen Marie Odroniec December 2006 Chair: Andrew Kennedy Major: Coastal and Oceanographic Engineering Three sediment budgets have b een developed for Jupiter Inlet, a tidal entrance that connects the Atlantic Ocean to the Loxahatchee River in southeast Florida. These budgets cover varying lengths of shoreline updrift and downdrift of the inlet and are based on two sources of survey data. Two of the three budgets are based on Florida Department of Environmental Protection (FDEP) profile surveys cove ring periods of 1974 to 1986, 1986 to 2002, and 1974 to 2002. The third budget is based on survey s provided by the Jupiter Inlet District (JID) and covers the period of August 2001 to October 2002. The fi rst budget covers a shoreline distance of approximately 26 km. The total period of 1974 to 2002 shows a net accumulation of sediment on the 8.53 km long downdrift beach of 122,600 m3 per year. Since the shoreline distances north and south of the inlet are not e qual, this sediment budget was believed to be the least accurate of the three. The second budget covers a shoreline distance of 14.5 km. This budget is be lieved to be more accurate in the respect

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xii that it covers equal distances of north and sout h shorelines. It was determined that from 1974 to 2002 there has been a net accumu lation of sediment on the 7.25 km long downdrift beach of 29,500 m3 per year. The third budget co vers a shoreline distance of about 1 km, with nearly equa l distances north and south of the inlet. From August 2001 to October 2002, there has been a net accumu lation of sediment on the downdrift beach of 65,600 m3 per year. Due to the variability in th e available ebb tidal delta volume data, two calculations of each of the three sedi ment budgets were made, one including delta volume change estimates and one excluding thes e estimates. The volumes given include the delta volume change estimates. When these changes are excluded from the calculations, net accumulated sediment volumes on the downdrift beach are about 2,100 m3 per year higher than those given. It is recommended that profile survey data be taken yearly for Palm Beach County Monuments R-3 to R-21, which cover approxi mately equal shoreline distances updrift and downdrift of the inlet. Also, the area that the ebb tidal delta covers should be identified and also surveyed on a yearly basis.

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1 CHAPTER 1 INTRODUCTION 1.1 Problem Statement Tidal inlets provide navigational access fr om the ocean to lagoons or bays for commercial and recreational purposes, and they also allow for the necessary exchange of waters, thus maintaining water quality and promoting life. However, some of the sediment that is transported along the coast often becomes trapped in the inlet channel during the flood tide and some is jetted far o ffshore during the ebb tid e rather than being deposited on the shore as would normally oc cur in the absence of an inlet. This interruption in the longshore sediment transport causes sh oreline erosion at beaches adjacent to the inlet (Dean and Dalrymple, 2002). Many inlets today have maintenance and ma nagement plans that were implemented in order to keep the channel open for navigation as well as to counteract the erosion that occurs at adjacent beaches. Jupiter Inlet in Fl orida is one such inlet that has an existing management plan due to its history of adj acent beach erosion as well as shoaling within the channel. In this stud y, the area surrounding this inlet was examined in order to determine the historical trend of beach and shoreline erosion and to assess the management plan for its effectiv eness in regulating beach erosion. 1.2 Objective and Tasks The objectives of this study were 1) to develop a sediment budget to analyze the effects of the beach nourishment that has been carried out adjacent to Jupiter Inlet and 2)

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2 to evaluate whether or not that nourishment has been successful in keeping the downdrift beach sufficiently nourished. The tasks undertaken for this study included: 1. Data compilation of the elements relevant to the sediment (sand) budget, including beach profiles, ebb shoal volumes, dredging volumes and nourishment volumes. 2. Determination of ebb shoal, dredging and nourishment data relevant to the locations and time periods being analyzed. 3. Calculation of the shoreline and volume ch ange rates at the beaches adjacent to Jupiter Inlet. 4. Presentation of sediment budget equation specifically for Jupiter Inlet. 5. Assessment of the beach nourishment’s efficacy after taking all data into consideration in the sediment budget equation. 1.3 Outline of Chapters Chapter 2 includes site descri ption and a summary of the recent engineering history of the Jupiter Inlet area as well as a summ ary of beach profile and sand volume data compiled for use in the sediment budget analys is. Chapter 3 details methods used to calculate shoreline and volume changes of th e beaches updrift and downdrift of Jupiter Inlet, describes the limitations of the profile data, and presents the shoreline and beach volume changes that took place within selected periods of time. The derivation of the sediment budget equation is given in Chap ter 4, followed by the presentation of the quantities used in the sediment budget and an explanation of the results of the sediment budget. A summary of the study as well as co nclusions and recommendations for further work are included in Chapter 5.

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3 CHAPTER 2 SITE DESCRIPTION AND DATABASE 2.1 Site Description and Recent History 2.1.1 Site Description Jupiter Inlet is a natural waterway mainta ined by the Jupiter Inlet District. The inlet connects the Loxahatchee River to the Atlantic Ocean, as shown in Figure 2-1. Figure 2-1: Jupiter Inlet c onnecting the Loxahatchee River forks to the Atlantic Ocean In the present study, three separate sedi ment budget analyses have been conducted for Jupiter Inlet for varying shoreline distances. Figure 2-2 displays the shoreline surrounding the inlet and depicts the loca tions of the Florida Department of Environmental Protection’s (FDEP) range monu ments. The first analysis encompasses an expanse of shoreline nearly 26 km in le ngth, with the study beginning at Monument R-75 in Martin County and continuing south to Monument R-40 in Palm Beach County. The second analysis covers a 14.5 km distance of shoreline, beginning with Monument R-112 N k m 1 0

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4 in Martin County and ending just past Monum ent R-36 in Palm Beach County. The final analysis encompasses a much shorter distance of shoreline of just over 1 km, beginning at Monument R-10 in Palm Beach County just north of Jupiter Inlet a nd extending south to Monument R-15. Jupiter Inlet is located be tween Monuments R-12 and R-13 in northern Palm Beach County. It is approximately 26 km south of St. Lucie Inlet and about 19 km north of Lake Worth Inlet, as shown in Figure 2-3 (Dombrowski and Mehta, 1993). The Jupiter Inlet system consists of jetties at the north and south banks of the inlet, a navigational channel and an interior sand tr ap. The jetties and th e location of the sand trap are displayed in Figure 2-4. Originally in 1922 the north and south jetties were each 120 m long and were built of rock. In 1929 both jetties were structurally strengthened and extended. The north jetty was extended 60 m and the south jetty 25 m. In 1956 a sheet-piled jetty 90 m long was constructed 30 m north of the pre-existing jetty. In 1967 the south jetty was extended by 30 m (Dom browski and Mehta, 1993). Between 1996 and 1998, the seaward end of the south jetty was lengthened by 53 m with a hook in the southeastward direction (Mehta et al., 2005). Jupiter Inle t is approximately 112 m wide with a mean depth of 3.9 m at the jetties. Maintained through dr edging, the navigational channel varies in width from about 206 m to 247 m and is also about 3.9 m deep (Patra, 2003). The interior sand trap located approximately 305 m we stward of the inlet mouth is intended to maintain the channel, to nourish the beach downdrift of the inlet by placement of sand dredged from the trap, and to reduce the influx of sediment into the Loxahatchee River (Stauble, 1993). 2.1.2 Recent History Jupiter Inlet has exis ted naturally for hundreds of year s. Originally, it was kept open by the flow that passed through it from the Loxahatchee River, Jupiter Sound, and

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5 Lake Worth Creek, closing intermittently due to natural events such as large storms (Grella, 1993). In more recent times, from the late 1800’s to the early 1900’s, the inlet closed more frequently than it had in the pa st due to the diversion of the natural flow caused by Lake Worth Inlet to the south and St Lucie Inlet to the north. The inlet was occasionally dredged and reopened during this period, but it would again close because of the decreased flow through it (Dombrowski and Mehta, 1993). Figure 2-2: FDEP range monuments north and south of Jupiter Inlet 0 1 km N

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6 Figure 2-3: Area map of Jupiter In let (Source: Buckingham, 1984, p. 3) Figure 2-4: Photograph of J upiter Inlet showing jetties a nd approximate location of sand trap N Sand Trap Jetties km 1 0

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7 The Jupiter Inlet District (JID) was creat ed in 1921 for the purpose of preserving and maintaining the inlet and the Loxahatchee Ri ver. As mentioned, the first jetties were built in 1922 and extended in 1929. However, the inlet closed again despite these stabilization efforts (Grella, 1993). To keep the inlet ope n for navigation, periodic dredging of a sand trap to a depth of appr oximately 6 m below mean water level was implemented in 1947. Since that time the in let has remained permanently open due to periodic dredging and maintenance of jetties. Since then, the jetties have been modified as mentioned, and the sand trap has been enla rged in order to reduce the entrance of littoral sediment into the inlet and to lessen the deposition of sedime nt further upstream of the trap (Mehta et al., 2005). 2.3 Beach Profile Data Two sources of data have been used to develop the three sediment budgets. The beach profile data used to conduct the analys es described in this report as the “FDEP Sediment Budget” were obtained from the Bure au of Beaches and Coastal Systems of the FDEP. Six sets of surveys consisting of b each profile data were obtained for Martin County and Palm Beach County. Three surveys within a period of nearly 30 years were found for each county. Ideally for this type of study the years in which the surveys were taken for each county would coincide, but matching survey dates were not available for Martin and Palm Beach Counties. The survey s that were found to be closest in dates were a 1976 survey for Martin County and a 1974 survey for Palm Beach County, a 1982 survey for Martin County and a 1990 survey for Palm Beach County, and a 2002 survey for Martin County and a 2001 survey for Palm Beach County. Table 2-1 lists the survey dates for each county as well as the beach profile type for each survey.

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8 Table 2-1: Beach profile data for Martin and Palm Beach Counties County Survey Date Profile Type 1976 Wading profiles every monument; long profiles every third monument 1982 Wading profiles every monument; long profiles every third monument Martin 2002 Wading and long profiles every monument 1974 Wading profiles every monument; long profiles every third monument 1990 Wading and long profiles every monument Palm Beach 2001 Wading and long profiles every monument A wading profile consists of distance and elevation measurements of the dry beach and includes measurements as far offshore as can be reached by wading or swimming, which typically reaches approximately 1.5 m of water depth. A long profile is taken by a surveying vessel and consists of the offs hore distance and depth measurements that cannot be reached by wading or swimming (Dean and Dalrymple, 2002). The long profiles have been plotted for the three surv ey dates for each county in Appendix A, from Monument R-75 in Martin County to Monument R-39 in Palm Beach County. The sediment budget analysis presented as the “JID Sediment Budget” uses beach profile data obtained from the J upiter Inlet District (JID). The profile data obtained from JID were taken by Lidberg Land Surveying of Jupiter, Florida. Nine surveys were available for the JID sediment budget analysis The first five were taken in May 1995, November 1995, May 1996, November 1996 and March 1997. These include Palm Beach County Monuments R-13 to R-17, which are south of Jupiter Inlet. The next three were taken in August 2001, June 2002 and October 2002 and incl ude Monuments R-10 through R-21 in Palm Beach County. The last survey was taken in April 2004 and includes Monuments R-13 through R-17 in Palm Beach County, south of the inlet. The beach profiles based on the JID profile da ta have been plotted in Appendix B.

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9 2.4 Ebb Shoal Volume Data Availability of Jupiter Inlet’s ebb shoal volume measurements was limited. One record (Dombrowski, 1994) found contained el even volume estimates taken in various years from 1883 to 1993. These volume measurem ents of the ebb shoal are presented in Table 2-2. Table 2-2: Jupiter Inlet ebb shoa l volumes (Source: Dombrowski, 1994) Year Volume (m3) 1883 690,000 1947 0 (inlet closed) 1957 380,000 1967 760,000 1978 310,000 1979 680,000 1980 310,000 1981 230,000 1986 690,000 1993 740,000 1993 1,530,000 A second source of ebb shoal volume data was found on the Palm Beach County Department of Environmental Resources Mana gement website. This source contained survey data taken of the Jupiter Inlet e bb tidal shoal for the years 2000 and 2001. Based on these surveys, volume changes were estimated between the two years. 2.5 Dredging Data Jupiter Inlet has an extensiv e history of dredging. Even in the early 1900’s the inlet was dredged simply to keep it open. As mentioned, since then, periodic dredging has been implemented with the creation of the sa nd trap. For the time pe riod covered in the sediment budget analyses, the material dredge d from the inlet channel and the trap has been placed on the beach downdr ift of Jupiter Inlet as nourishment. Volumes dredged from the channel and the trap between 1974 and 2004 are presented in Table 2-3. The

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10 data were obtained from Michael Grella of JID (personal communication, March 20, 2006). The dredged sediment volumes betw een 1974 and 2001 within the limits of the sediment budget for Palm Beach County for th e FDEP budget have an annual average value of approximately 34,800 m3 over that total period. The dredged volumes in 2001 and 2002 within the limits of the sediment budget using the JID beach profiles have an annual average of about 48,500 m3. Table 2-3: Jupiter Inlet and in terior sand trap dredging volumes Year Dredged Volume (m3) 1975 75,003 1977 68,733 1979 71,104 1981 57,342 1983 45,873 1985 58,106 1986 50,078 1988 52,984 1990 64,987 1991 43,466 1993 47,030 1994 54,681 1995 55,048 1996 24,114 1998 64,987 2000 42,968 2001 63,382 2002 33,640 2004 43,580 2.6 Beach Nourishment Data 2.6.1 Downdrift Beach Nourishment Volumes Records of downdrift nourishment events ar e shown in Table 2-4. The data were obtained from Michael Grella of JID (p ersonal communication, March 20, 2006), from the Beach Erosion Control Project Monitoring Database Information System maintained by the Beaches & Shores Resource Center of the Florida State University, Tallahassee

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11 and from a report prepared by Taylor Engi neering for Palm Beach County (Albada and Craig, 2006). The volumes of sediment dredge d from the inlet channel and the sand trap, as shown previously in Tabl e 2-3, are taken to be equal to the volumes of sediment placed on the beach from the dredging, a nd therefore are incl uded in the total nourishment volumes shown in Table 2-4. The Jupiter Inlet Management Plan, approved by JID in 1992, adopted 46,000 m3 as the minimum sand volume to be placed on the downdrift beach annually (Grella, 1993). Prior to that plan, a section of the beach about 244 m in length just south of the jetty was used for the placement of nourishment. In order to increase the retention time of the same volume of sand, this length of beach was doubled to approximately 488 m as shown in Figure 2-5 (Mehta et al., 2005). The two key sources of sediment used for beach nourishment downdrift of Jupiter Inlet are the sand trap and th e Intracoastal Waterway, as s hown in Figure 2-6. The sand stored in the sand trap is dr edged nearly every year. Als o, excess sand is dredged from the Intracoastal Waterway by the U. S. Army Corps of Engineers as well as the Florida Inland Navigation District (FIND), and a portion of the dredged sediment is placed on the downdrift beach. The recommended plan for the nourishment of the beach is that the dredging of the sand trap be completed before the end of April each year and placed on the beach. If this volume is insufficient at that time, then dredging should be conducted in November instead. It has also been reco mmended that the Intracoastal Waterway be dredged and the sediment placed on the downdrif t beach in April if th e sand trap has been dredged in November, or in November if the sand trap has been dredged in April (Grella, 1993).

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12 Table 2-4: Jupiter Inlet dow ndrift beach nourishment volumes Year Time of Year of Nourishment (If Available) Total Nourishment Volume (m3) Approximate Placement of Nourishment Source(s) of Sediment 1975 192,744 Monument R-13 to R-14 Inlet/Sand Trap, Intracoastal Waterway 1977 68,733 Monument R-13 to R-14 Inlet/Sand Trap 1979 161,933 Monument R-13 to R-14 Inlet/Sand Trap, Intracoastal Waterway 1981 57,342 Monument R-13 to R-14 Inlet/Sand Trap 1983 45,873 Monument R-13 to R-14 Inlet/Sand Trap 1985 58,106 Monument R-13 to R-14 Inlet/Sand Trap 1986 50,078 Monument R-13 to R-14 Inlet/Sand Trap 1988 132,115 Monument R-13 to R-14 Inlet/Sand Trap, Intracoastal Waterway 1989 8,792 Monument R-13 to R-14 Intracoastal Waterway 1990 64,987 Monument R-13 to R-14 Inlet/Sand Trap 1991 43,466 Monument R-13 to R-14 Inlet/Sand Trap 1992 106,273 Monument R-13 to R-15 Intracoastal Waterway 1993 47,030 Monument R-13 to R-15 Inlet/Sand Trap 1994 54,681 Monument R-13 to R-15 Inlet/Sand Trap 1995 November 1995 to February 1996 139,530 Monument R-13 to R-15 Inlet/Sand Trap, Intracoastal Waterway 1995 Spring 461,635 Monument R-18 to R-19 (Carlin Park) Ebb Tidal Delta 1996 24,114 Monument R-13 to R-15 Inlet/Sand Trap 1998 64,987 Monument R-13 to R-15 Inlet/Sand Trap 2000 Contract Award February 2000 70,171 Monument R-13 to R-15 Inlet/Sand Trap, Intracoastal Waterway 2001 Contract Award February 2001 112,948 Monument R-13 to R-15 Inlet/Sand Trap, Intracoastal Waterway 2002 Contract Award February 2002 33,640 Monument R-13 to R-15 Inlet/Sand Trap 2002 December 2001 to March 2002 477,844 Monument R-18 to R-19 (Carlin Park) Borrow Area Approx. 3.2 km NE of Jupiter Inlet 2004 January 2004 to March 2004 127,681 Monument R-13 to R-15 Inlet/Sand Trap, Intracoastal Waterway

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13 Figure 2-5: Jupiter Inlet Management Plan recommended increase in nourishment beach length (Source: Grella, 1993, p. 247) Figure 2-6: Sand trap and In tracoastal Waterway depositi on basin from which sediment is dredged to be used as nourishm ent (Source: Buckingham, 1984, p. 7)

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14 2.6.2 Updrift Beach Nourishment Volumes Some nourishment events have also occurr ed on the beach updrift of Jupiter Inlet for the time period under consideration for the FDEP sediment budget analyses. The volumes that were placed on the updrift beach are presented in Table 2-5. Based on Aubrey and Dekimpe, 1988, a ll except two of th e updrift nourishment events that occurred through 1987 were placed within the bounds of Monument R-75 and Monument R-111 of Martin County. The first 1983 nourishment as well as the 1986 nourishment are known to have been placed just north of Jupiter Inlet in Palm Beach County, but the exact locations are uncertai n. From the records obtained from the Beaches & Shores Resource Center, the 1995/1996 nourishment is known to have been placed between Monuments R-77 and R-106 of Martin County. A renourishment project was scheduled for 2001 for Jupiter Island updrift of the inlet, but no indication that the placement had occurred could be found (Tabar et al., 2002). Table 2-5: Jupiter Inlet updr ift beach nourishment volumes Year Nourishment Volume (m3) Source of Data 1974 741,618 Aubrey and Dekimpe, 1988 1977 366,986 Aubrey and Dekimpe, 1988 1978 649,872 Aubrey and Dekimpe, 1988 1983 108,414 Michael Grella (personal communication, March 20, 2006) 1983 764,555 Aubrey and Dekimpe, 1988 1986 116,916 Michael Grella (personal communication, March 20, 2006) 1987 1,704,957 Aubrey and Dekimpe, 1988 1995/1996 1,330,325 Beaches & Shores Resource Center

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15 CHAPTER 3 SHORELINE AND BEACH VOLUME CHANGES 3.1 Shoreline and Beach Volume Change Calculation Methods Two main components that form the basis for the sediment budget for Jupiter Inlet are the updrift and downdrift beach volume cha nge rates. In order to determine these rates, two computer progra ms that were developed by Dr. Robert Dean (personal communication, June, 2005) for use in an ear lier development of a sediment budget for Sebastian Inlet, also locate d along the east coast of Florid a (Dean, 2005), were modified and used. The first program inputs beach pr ofile survey data. These surveys were obtained from the FDEP’s Bureau of Beaches and Coastal Systems database and from records provided by the Jupiter Inlet District. The program organizes the input data for plotting profiles at each survey monument a nd calculates shoreline position changes and the unit volume (i.e., volume of sediment per unit beach width) changes for the determined time period based on these survey data. For each monument that has a long survey profile, the profile area between th e water level (NGVD) and the sand surface from a selected (base line) position on land to the depth of closur e is estimated by the trapezoidal rule. The change in area from one su rvey date to the next is then calculated in order to find accretion or erosion that has occu rred at the monument in that period. This area change is then represented as the co rresponding unit volume change for use in the second program. The second program analyzes the shor eline position and unit volume change calculations that are output from the first pr ogram, and determines the average shoreline

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16 and volumetric changes per year. In order to determine the volumetric change per year, the unit volume change from an earlier survey date is subtracted from the unit volume change from a subsequent survey date. The unit volume change is then divided by the number of years in between the survey dates to obtain the unit volume change rate. In order to obtain the volume change rates for the intersurvey periods analyzed, the end-area method is used, which averages the unit vol ume change rates at each monument, and multiplies this rate by the distance between each monument. The second program also allows for the calculation of the volume change rate at user-specified points that need to be examined closely, for example, at the north and south boundaries of the inlet. From these two programs, the total vol umetric rates of gain or loss of sediment are determined for the beaches updrift and downdr ift of the inlet. These va lues are then used in the determination of the sediment budget, as described in Chapter 4. 3.2 Data Limitations and Uncertainties There are several uncertainties to be aware of when using beach profile survey data to calculate volumetric changes. As mentione d in Chapter 2, beach profile measurements are taken using two surveying processes, the first being the wading survey, and the second being the boat survey. The wading portio n of the survey is conducted by a survey crew which uses “standard land surveying equipment” to determine the elevations of the dry beach, and as far offshore as is possibl e to reach by wading or swimming, typically up to about 1.5 m of water depth. Usually, a surveying vessel is used to obtain the offshore portion of the survey. This vessel commonly has a fathometer and a coordinate positioning system onboard so that the vessel’ s position can be correlated with depth measurements (Dean and Dalrymple, 2002). Ea rly surveys, however, did not have the same level of technology that is used now especially for the offshore portion of the

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17 survey. Generally, vessels had to stay on the profile line visually by using the range poles, so errors were more prevalent in the offshore depth measurements. 3.2.1 Data Uncertainties Occasionally, there are discre pancies other than measurem ent errors in the beach profile survey data. For example, in th e survey made in 1976 in Martin County, monument coordinates were missing for M onument R-84. It was documented in the FDEP database that the monument had been relocated after the 1976 survey and before the 1982 survey, so using the coordinates of Monument R-84 from the most recent survey, which is a common way to correct such a data omission, would have been inaccurate. Therefore, aerial photographs taken in 1972 and checked in 1975 for accuracy were inspected, and distances were scaled from Monuments R-83 to R-84 and from R-84 to R-85. Based on these distances and on the coordinates of Monuments R83 and R-85 documented in the 1976 surve y, coordinates for Monument R-84 were obtained by interpolation. This seemed the most reliable method because of the proximity in time between the aerials and the survey, and also because it took into account an estimate of the distance between the monuments, rather than assuming that the monuments were evenly spaced. An additional uncertainty occurred in the 1982 survey at Monument R-105 of Martin County. As mentioned, the early su rveys only had long profiles recorded for every third monument; theref ore R-105 should have had long profile measurements for each survey date. However, in 1982 the meas urements were only taken to an offshore distance of about 45.7 m, with a corresponding maximum depth of -1.6 m. Because the depth of closure (which is the offshore lim it of a volume calculation) was not reached in the measurements, a unit volume change could no t be calculated at this location. Thus,

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18 for the periods from 1976 to 1982 and from 1982 to 2002 in Martin County, the beach volume change rates had to be estimated based on unit volume changes at Monuments R102 and R-108 and averaged over the distance be tween these two monuments, which is a longer distance than the usual every third m onument distance that was normally used for the other early survey calculations. 3.2.2 Corrections for Non-Closure of Profiles The depth of closure is a depth at whic h all beach profiles from any given time normally converge (and do not diverge signi ficantly again beyond this depth), as exemplified in Figure 3-1 (Dean and Dalrymple, 2002). For the calculations made in the previously mentioned programs, the seaw ard distance corresponding to the depth of closure from the shoreline was used as a limit for the volume calculations. It can be seen from the beach profiles shown in Appendices A and B that there is non-closure of many of the profiles. These data suggest that there was probably some error in the 1976 and 1982 surveys from Martin County, and the 1974 survey from Palm Beach County. Figure 3-1: Schematic diagra m defining depth of closure, where all offshore profiles converge to a certain depth Local depth of closure Shoreline

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19 Because of the lack of obvious closure depth in the Martin County profiles, and questionable closure depth in the Palm Beach County profiles, a method other than visual inspection had to be used to determine a mean closure depth for each county. The standard deviation of the de pths at every monument was calculated separately at the shoreline and at every 25 m distance offshor e for each county. The depth of closure was chosen at the point where the standard deviati on was the least. These closure depths were -3.66 m at a 350 m distance from the shorelin e in Martin County, a nd -3.11 m at a 250 m distance from the shoreline in Palm Beach C ounty. As described later, sediment volume analysis was extended by examining the eff ect of changing (increasing and decreasing) the depth of closure. This was done in orde r to make a quantitativ e assessment of the error introduced by selecting a pa rticular depth of closure. 3.2.3 Corrections for Monument Relocation After the 1976 survey for Martin Count y and the 1974 survey for Palm Beach County, some of the monuments were relocated by FDEP, including Monument R-84 of Martin County as mentioned earlier. The firs t of the two programs used for the beach volume calculations accounts for monument re location. It compar es the monument coordinates from survey to surv ey, and if the coordinates diffe r, it calculates the distance between the monument’s old location and its new location. If this distance exceeds 0.031 m, then an appropriate shift is calculated and added algebraically to every distance measured along the profile of the original monument. 3.3 FDEP Intersurvey Interval: 1974-1986 For the FDEP intersurvey interval of 1974 to 1986, shoreline change data were available for every monument. However, unit vo lume change rates for this interval could only be calculated for every third monument b ecause in the earlier surveys, including the

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20 1976 and 1982 surveys for Martin County and the 1974 survey for Palm Beach County, long beach profiles were taken for only the first monument of a county and for every third monument thereafter. Therefore, the unit volume change rates could only be found for the long beach profiles, in which depths a nd distances were recorded up to the depth of closure. 3.3.1 Shoreline Changes Figure 3-2 displays the shoreline change rates for each monument for the period between the 1976 and 1982 FDEP surveys in Martin County, and between the 1974 and 1990 FDEP surveys in Palm Beach County. The largest rate of accret ion of the shoreline updrift of Jupiter Inlet based on these data is almost 6.25 m per year at Monument R-84 in Martin County, and the larges t rate of erosion of the updrif t shoreline is nearly 4 m per year at R-105 in Martin County. The shorel ine change rates on the updrift side of the inlet show accretion as we ll as erosion, with no obvious mean trend. Downdrift of Jupiter Inlet, the highe st rate of shoreline accretion observed is ar ound 2.4 m per year at Monuments R-25 and R-26 in Palm Beach C ounty, and the highest rate of shoreline erosion is just over 2 m per year at R-29 in Palm Beach County. The shoreline change downdrift of the inlet for this time period tends to show trends of accretion with smaller amounts of erosion interspersed. 3.3.2 Sediment Volume Changes The unit volume change rates for each m onument for the period between the 1976 and 1982 FDEP surveys in Martin County and for the 1974 and 1990 FDEP surveys in Palm Beach County are shown in Figure 3-3. The largest volumetric rate of accretion occurring updrift of Jupi ter Inlet is about 22 m3/m per year at Monument R-84 in Martin County, and the largest volumetri c rate of erosion updrift of the inlet is nearly 30 m3/m

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21 per year at R-93 in Martin County. The un it volume change rates on the updrift side of the inlet show sections of the beach havi ng high accretion as well as high erosion, where neither accretion nor erosion dominates. Dow ndrift of the inlet, the highest volumetric rate of accretion is almost 12 m3/m per year at Monument R-27, and the highest volumetric rate of erosion is just over 9 m3/m per year at R-36. The unit volume change rates downdrift of the inlet fo r this period show a small degr ee of erosion just past the inlet, with high accretion just past the eros ional stretch. Further downdrift, accretion and erosion occur without a noticeable trend. 3.4 FDEP Intersurvey Interval: 1986-2002 For the FDEP intersurvey interval of 1986 to 2002, shoreline change data were available for every monument. For Martin County, unit volume change rates for this interval could be calculated for only every third monument. Alt hough the second survey of the interval is from 2002 and contains l ong beach profile data for every monument, the first survey of the interval is from 1982, which has long beach profiles for only every third monument. Therefore, the unit volume ch ange could only be calculated for those monuments which had long beach profile survey data for both years. For Palm Beach County, the unit volume changes for this inte rval were calculated for every monument because the surveys were from 1990 and 2001, each of which had long beach profile surveys for every monument. 3.4.1 Shoreline Changes Figure 3-4 displays the shoreline change rates for each monument for the period between the 1982 and 2002 FDEP beach profile surveys in Martin County, and between the 1990 and 2001 FDEP surveys in Palm Beach County. Updrift of Jupiter Inlet, the highest rate of shoreline accretion is ar ound 3 m per year at Monument R-10 in Palm

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22 Beach County, with R-106, R-118, and R-120 havi ng similarly high rates of accretion. The rate of shoreline erosion is comparativ ely small and does not even reach 0.5 m per year at any point. For this pe riod, the shoreline change rate updr ift of the inle t tends to be accretive. On the shoreline downdrift of Jup iter Inlet, the highest rate of accretion is around 5 m per year at Monument R-36 and n early the same at R-31 in Palm Beach County. The highest rate of erosion is around 2.75 m per year at Monuments R-14 and R-23 in Palm Beach County. Erosion and accretion both occur up to about Monument R26, and past this point high accretion occurs. 3.4.2 Sediment Volume Changes The unit volume change rates for each m onument for the period between the 1982 and 2002 FDEP beach profile surveys in Martin County and for 1990 and 2001 in Palm Beach County are displayed in Figure 3-5. Updr ift of Jupiter Inlet, the highest rate of volumetric accretion is about 20 m3/m per year at Monument R-10 in Palm Beach County, with the next highest rate at R-120 in Martin County. These two locations displaying high volumetric accretion rates coin cide with two of the locations showing high shoreline accretion rates. The largest rate of volumetric erosion updrift of the shoreline occurs at Monument R-12 of Pa lm Beach County, with a value of about 21.75 m3/m per year. All other volumetric rates of erosion updrift of the inlet are below 8.5 m3/m per year, and few locations display erosion. For this period, similar to the shoreline change rates updrift of the in let, the unit volume change rates tend to be accretive. Downdrift of the inlet, th e highest volumetric rate of accretion is nearly 39 m3/m per year at Monument R-30 in Palm Beach County. The highest volumetric rate of erosion is nearly 20 m3/m per year at R-13 in Palm Beach County. The unit volume change rate

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23 downdrift of the inlet sh ows drastic erosion immediately dow ndrift, and then it is mainly accretive for the rest of the beach length analyzed. 3.5 FDEP Intersurvey Combined Interval: 1974-2002 For the FDEP intersurvey co mbined interval of 1974 to 2002, the shoreline change rates were calculated at ev ery monument. However, the unit volume change rates could be calculated only for every third monument. For Martin County, the first survey for this interval is from 1976 and contains long beach profile survey data for every third monument, while the second survey is from 2002 and contains long beach profiles for every monument. For Palm Beach County, th e first survey is from 1974 and contains long beach profiles for the first monument and every third monument thereafter, and the second survey is from 2001 and contains long beach profiles for every monument. Therefore, for both counties, unit volume change rates c ould be determined only for every third monument. 3.5.1 Shoreline Changes Figure 3-6 shows the shoreline change rates for the total time period analyzed, from 1976 to 2002 in Martin County and 1974 to 2001 in Palm Beach County. The shoreline change rates updrift and downdrif t of Jupiter Inlet mainly sh ow trends of accretion for this time interval. Immediately updrift and dow ndrift of the inlet, th ere is more variation, with erosion at Monuments R-12 and R-13 in Palm Beach County, but overall the shoreline is seen to have accreted. The highest rate of accretion updrift of the inlet is just over 2 m per year in Martin County, and the hi ghest rate of erosi on updrift is about 1.25 m per year in Palm Beach County at Monumen t R-12. On the shoreline downdrift of the inlet, the highest rate of accretion is around 2.5 m per y ear at Monument R-31, and the highest rate of erosion is al most 1.4 m per year. Downdrif t of the inlet, erosion only

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24 occurs over two small stretches of the shoreline, with the re st of the shoreline showing accretion. 3.5.2 Sediment Volume Changes The unit volume change rates from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County are shown in Figur e 3-7. Updrift of Jupiter Inlet, there are large stretches of volumetric accretion with one notable stretch of erosion from about Monument R-90 to R-105. The largest unit volum e change rate showing erosion updrift of the inlet occurs at Monument R-12 in Palm Beach County and is nearly 14 m3/m per year. Downdrift of the inlet, there is a small amount of volumetric erosion adjacent to the inlet, at Monument R-15. Consistent with th e trends that were displayed by the shoreline change rates for this period, the unit volume ch ange rates also display mainly trends of accretion. Figure 3-2: Shoreline cha nge rates for the period from 1976 to 1982 in Martin County and from 1974 to 1990 in Palm Beach County

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25 Figure 3-3: Unit volume change rates for th e period from 1976 to 1982 in Martin County and from 1974 to 1990 in Palm Beach County Figure 3-4: Shoreline cha nge rates for the period from 1982 to 2002 in Martin County and from 1990 to 2001 in Palm Beach County

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26 Figure 3-5: Unit volume change rates for th e period from 1982 to 2002 in Martin County and from 1990 to 2001 in Palm Beach County Figure 3-6: Shoreline change rates for the combined period from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County

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27 Figure 3-7: Unit volume change rates for the combined period from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County 3.6 Volume Change Sensitivity to Depth of Closure As mentioned, because the depths of closur e were not obvious from the plots of the beach profiles, the standard deviation method was used to find the mean depth of closure for each county. Thus it was necessary to check for any significant sources of error introduced by assuming these values of the depth of closure. Depths of closure of -3 m and -4 m were used for computing sediment volumes to compare with those determined using the standa rd deviation-derived de pths of closure. These two depths were chosen because they bracket the -3.66 m used for Martin County and the -3.11 m used for Palm Beach Count y. The -3 m depth represents an 18 % decrease from the original -3.66 m for Martin County and only a 3.5 % decrease from the -3.11 m for Palm Beach County. The -4 m depth introduces only a 9.3 % increase for Martin County and a 28 % incr ease for Palm Beach County.

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28 For all time periods considered, sp ecifically 1976 to 1982, 1982 to 2002 and 1976 to 2002 for Martin County and 1974 to 1990, 1990 to 2001 and 1974 to 2001 for Palm Beach County, the unit volume change rate differences between the -3 m depth of closure volumes and the standard deviation-derived de pth of closure volumes were considerably larger in Martin County than in Palm Beach County. This can be attributed to the fact that the standard deviation-derived depth of closure of -3.11 m for Palm Beach County is closer to -3 m than the standard deviati on depth of -3.66 m for Martin County. For the first and last time periods considered which are 1976 to 1982 and 1976 to 2002 for Martin County and 1974 to 1990 and 1974 to 2001 for Palm Beach County, the unit volume change rate differences between th e -4 m depth of closure volumes and the standard deviation depth of closure volumes were larger in Palm Beach County than in Martin County. This is because the standard deviation depth for Martin County is closer to -4 m than for Palm Beach County. Although the unit volume change rates do differ for each county when the depths of closure are va ried, these differences are minor. This can be seen in Figures 3-8, 3-9, and 3-10. 3.6.1 Volume Change Sensitivity to Depth of Closure: 1974 to 1986 For the first period, from 1976 to 1982 in Martin County and from 1974 to 1990 in Palm Beach County, the unit volume change rate s corresponding to all depths of closure are displayed in Figure 3-8. On average, the unit volume change rate differences found by subtracting the standard deviation depth volumes from the -3 m depth volumes were approximately 1 m3/m per year and -0.56 m3/m per year, respectively. This means that within the first period of time considered, th e unit volume change rate corresponding to -3 m is greater than the rate for -3.66 m in Martin County, and the ra te for -3 m is less than the rate for -3.11 m in Palm Beach C ounty. For the same time period, the rate

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29 differences between -4 m depth volumes and the standard deviation depth volumes were on average about -0.68 m3/m per year and 1.68 m3/m per year for Martin County and Palm Beach County, respectively. Therefore, the unit volume change rate corresponding to -4 m is less than the rate fo r -3.66 m in Martin C ounty and greater than th e rate for -3.11 m in Palm Beach County. Figure 3-8: Unit volume change rates using va rying depths of closure for the period from 1976 to 1982 in Martin County and from 1974 to 1990 in Palm Beach County 3.6.2 Volume Change Sensitivity to Depth of Closure: 1986 to 2002 For the second period from 1982 to 2002 in Martin County and from 1990 to 2001 in Palm Beach County, the unit volume change rates for all depths of closure are shown in Figure 3-9. The unit volume change rate differences found by subtracting the standard deviation depth volumes from the -3 m depth volumes were on average about 1.3 m3/m per year and 0.2 m3/m per year, respectively. This mean s that the rate corresponding to -3 m is greater than the rate for -3.66 m in Ma rtin County and is also greater than the rate

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30 for -3.11 m in Palm Beach County. The rate differences between -4 m depth volumes and the standard deviation de pth volumes were about -0.35 m3/m per year on average for Martin County and -0.22 m3/m per year on average for Pa lm Beach County. This means that rates corresponding to -4 m are less than the rates corr esponding to -3.66 m in Martin County and -3.11 m in Palm Beach County. Figure 3-9: Unit volume change rates using va rying depths of closure for the period from 1982 to 2002 in Martin County and from 1990 to 2001 in Palm Beach County 3.6.3 Volume Change Sensitivity to Depth of Closure: 1974 to 2002 The unit volume change rates for all dept hs of closure for the combined period from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County are displayed in Figure 3-10. The average un it volume change rate differences found by subtracting the standard de viation depth volumes from the -3m depth volumes were around 1.37 m3/m per year and -0.33 m3/m per year for Martin County and Palm Beach County, respectively. This mean s that the rate corresponding to -3 m is greater than the

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31 rate for -3.66 m in Martin County, and that the rate for -3 m is less than the rate for -3.11 m in Palm Beach County. The unit volume change rate differences between -4 m depth volumes and the standard deviation dept h volumes were on average about -0.48 m3/m per year for Martin County and 0.60 m3/m per year for Palm Beach County. Therefore, the unit volume change rates corresponding to -4 m are less than the rates for -3.66 m in Martin County and more than the rate s for -3.11 m in Palm Beach County. Figure 3-10: Unit volume change rates using va rying depths of closure for the combined period from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County 3.7 JID Intersurvey Interval: 1995-1996 For the JID intersurvey interval of May 1995 to May 1996, both the shoreline and the unit volume change rates were calculated just south of Jupiter Inlet for Monuments R13 to R-17.

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32 3.7.1 Shoreline Changes The shoreline change rates at each monume nt are displayed in Figure 3-11 for the period between the 1995 and 1996 JID survey s in Palm Beach County. The highest accretion rate seen on this downdrift shorel ine is about 9.4 m per year at Monument R13. The shoreline continues to show trends of accretion until about R-15, where it begins to be erosive. This continues to R-17 wher e the highest rate of erosion of 21.3 m per year is seen. 3.7.2 Sediment Volume Changes Figure 3-12 displays the unit volume cha nge rates for each monument for the period between the 1995 and 1996 JID surveys in Palm Beach County. The shoreline is seen to accrete from Monument R-13 to R-15. The highest rate of volumetric accretion is just over 81 m3/m per year occurring at Monument R-13. Past Monument R-15, the shoreline is erosive, with the highest rate being 178 m3/m per year at Monument R-17. 3.8 JID Intersurvey Interval: 1996-1997 For the JID intersurvey interval of Ma y 1996 to March 1997, both the shoreline and the unit volume change rates were calculated for Monuments R-13 to R-17, just south of Jupiter Inlet. 3.8.1 Shoreline Changes Figure 3-13 displays the shoreline change rates at each monument for the period between the 1996 and 1997 surveys in Palm Beach County. The highest rate of accretion is seen to be just over 42 m per year at Monument R-13, just downdrift of the inlet. The highest rate of erosion is 28.5 m per year at Monument R-15. This stretch of shoreline is accretive directly downdrift of the inlet, st arts to erode near Monument R-15, and then begins accreting again after Monument R-16.

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33 3.8.2 Sediment Volume Changes The unit volume change rates for each m onument for the period between 1996 and 1997 in Palm Beach County are displayed in Fi gure 3-14. The largest rate of volumetric accretion occurs at Monument R-13, with a value of 152.3 m3/m per year. The highest rate of volumetric erosion is 238.3 m3/m per year at Monument R-15. This stretch of shoreline displays mostly erosion, with accr etion occurring only at Monuments R-13 and R-16. 3.9 JID Intersurvey Combined Interval: 1995-2004 For the JID intersurvey combined interval of May 1995 to April 2004, both the shoreline and the unit volume ch ange rates were calculated ju st south of Jupiter Inlet for Monuments R-13 to R-17. 3.9.1 Shoreline Changes Figure 3-15 displays the shoreline change rates at each monument for the period between the 1995 and 2004 JID surveys in Palm Beach County. The only location where accretion occurs is at Monument R-13 where th e rate is about 1.3 m per year. Over the rest of the length of shoreline there is a slightly erosive tre nd. The highest rate of erosion is 5.3 m per year and occurs at Monument R-15. 3.9.2 Sediment Volume Changes The unit volume change rates from 1995 to 2004 in Palm Beach County are shown in Figure 3-16. Monument R-13 is the only lo cation showing accreti on, with a rate of about 19 m3/m per year. The rest of the shorel ine from Monument R-14 to R-17 shows erosive trends. The larg est rate of volumetric erosion is just over 32 m3/m per year at Monument R-15.

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34 3.10 JID Intersurvey Interval: 2001-2002 Shoreline and unit volume change rates for the JID intersurvey interval of August 2001 to October 2002 were calculated separately from the 1995, 1996, 1997 and 2004 JID data. This is because the 2001 and 2002 surveys included data for Monuments R-10 through R-21 whereas the other surveys incl uded data only for Monuments R-13 to R-17, south of Jupiter Inlet. For the JID inters urvey interval of August 2001 to October 2002, both the shoreline and the unit volume change rates were calculated at every monument. 3.10.1 Shoreline Changes Figure 3-17 displays the shoreline change rates at each monument for the period between the 2001 and 2002 JID surveys in Palm Beach County. There are only profiles for three monuments on the updrift side of the in let, at which the highest rate of accretion is approximately 3.4 m per year at Monument R-10 and the highest rate of erosion is nearly 3.75 m per year at R-12. On the shorel ine downdrift of the inle t, the highest rate of accretion is seen to be ju st over 40 m per year at R-18, whereas the highest rate of erosion, which is also the only erosion seen over the analyzed distance, is only around 7 m per year at R-20. The downdrift shoreline displays a mainly accretive trend between 2001 and 2002. 3.10.2 Sediment Volume Changes The unit volume change rates for each m onument for the period between the 2001 and 2002 JID beach profile surveys in Palm Beach County are displayed in Figure 3-18. Updrift of Jupiter Inlet, the highest rate of volumet ric accretion is almost 11 m3/m per year at Monument R-10. The largest rate of volumetric erosion updrift of the inlet occurs at Monument R-12, with a value of just over 25 m3/m per year. Downdrift of the inlet, the highest volumetric rate of accretion is nearly 200 m3/m per year at Monument R-18.

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35 Erosion on the downdrift side of the inlet is seen at only one m onument, R-20, and is only approximately 3.75 m3/m per year. The unit volume change rate downdrift of the inlet shows accretion immediatel y downdrift, and the trend is mainly largely accretive for the rest of the analyzed beach length as we ll, with only one monument showing low rates of erosion. Figure 3-11: Shoreline change rates for the period from 1995 to 1996 just south of Jupiter Inlet in Palm Beach County Figure 3-12: Unit volume change rates for the period from 1995 to 1996 just south of Jupiter Inlet in Palm Beach County

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36 Figure 3-13: Shoreline change rates for the period from 1996 to 1997 just south of Jupiter Inlet in Palm Beach County Figure 3-14: Unit volume change rates for the period from 1996 to 1997 just south of Jupiter Inlet in Palm Beach County

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37 Figure 3-15: Shoreline change rates for the combined period from 1995 to 2004 just south of Jupiter Inlet in Palm Beach County Figure 3-16: Unit volume change rates for the combined period from 1995 to 2004 just south of Jupiter Inlet in Palm Beach County

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38 Figure 3-17: Shoreline change rates for the period from 2001 to 2002 in Palm Beach County Figure 3-18: Unit volume change rates for the period from 2001 to 2002 in Palm Beach County

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39 CHAPTER 4 SEDIMENT BUDGET 4.1 Sediment Budget Methodology 4.1.1 Sediment Budget Equation This section presents the development of the sediment budget methodology applied to Jupiter Inlet. The elements included in the budget account for all possibilities of sediment entering, leaving or being stored within the area of c onsideration (Rodriguez and Dean, 2005). For Jupiter Inlet, the volum etric storage elements include the updrift and downdrift beach systems and the ebb tidal shoal. To fully illustrate the sediment budget methodology, the rates of volume change on the updrift and downdrift beaches will be described using a ll possible volume storage components as displayed in Figure 4-1. Late r, the components that are unimportant to Jupiter Inlet will be deleted. The rate of volum e gain for the updrift beach is described in Equation (4-1) and the rate of volume gain for the downdrift beach is described in Equation (4-2) as follows (Dean, 2005): UB BB UB ST UB EBB UB OS IN UBQ Q Q Q Q dt dV, , (4-1) DR NOUR DB BB DB ST DB EBB DB OS OUT DBQ Q Q Q Q Q Q dt dV , , (4-2) where: DB UBdt dV dt dVorvolumetric rate at which sediment is accumulated in the updrift or downdrift beaches, respectively,

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40 OUT INQ Q orvolumetric rate at which sediment enters the updrift beach or leaves the downdrift beach through litto ral transport, respectively, DB OS UB OSQ Q, ,orvolumetric rate at which sediment enters the updrift or downdrift beaches through onshore transport, respectively, DB EBB UB EBBQ Q, ,orvolumetric rate at which sediment is accumulated in the ebb tidal shoal from the updrift or dow ndrift beaches, respectively, DB ST UB STQ Q, ,orvolumetric rate at which sediment is accumulated in the interior sand trap from the updrift or downdrift beaches, respectively, DB BB UB BBQ Q, ,orvolumetric rate at which sediment is accumulated in the back bay region from the updrift or dow ndrift beaches, respectively, NOURQ annual average volumetric nourishment rate of the downdrift beach with sediment provided from outside of the system, and DRQvolumetric rate at which sediment is dredged from the interior sand trap. Combining Equations (4-1) and (4-2) yields the total volumetric rate at which sediment is stored on the updrif t and downdrift beach systems: DR NOUR DB BB UB BB DB ST UB ST DB EBB UB EBB DB OS UB OS OUT IN DB UBQ Q Q Q Q Q Q Q Q Q Q Q dt dV dt dV , , , , (4-3) The sediment budget is based on the premise that, if the inlet were non-existent, the processes along the same shoreline distance updrift and downdrift of the inlet would be identical. Therefore, over the same l ongshore distances, the beaches updrift and downdrift should be eroding or accreting at the same rate (Dean, 2005). Theoretically, with no inlet, the volume changes on equa l lengths of updrift and downdrift beaches would be equal; that is, each would be one half of the total volume change: DB OS UB OS OUT IN DB UBQ Q Q Q dt dV dt dV, ,2 1 (4-4) However, due to the presence of the inlet a nd sediment likely being transported into the inlet channel, not all sediment coming from th e updrift side of the inlet is transported to the beach downdrift of the in let. Therefore, the differe nce between the actual volume

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41 change rate that has occurre d on the downdrift beach and the theoretical volume change rate of the downdrift beach represents the ye arly excess or deficit of nourishment that has been placed on the downdrift beach, as follows: DB OS UB OS OUT IN DB DIFFERENCEQ Q Q Q dt dV Q, ,2 1 (4-5) In this context, a positive QDIFFERENCE value would indicate that there is a quantity of sediment on the downdrift beach in excess of the amount that would be there in the absence of the inlet, whereas a negative value would repres ent a deficit of sediment. Rearranging equation (4-3), it can be seen that: NOUR BB ST EBB UB DB DB OS UB OS OUT INQ dt dV dt dV dt dV dt dV dt dV Q Q Q Q 2 1 2 1, (4-6) where the following substitutions have been made for the ebb tidal shoal, sand trap, and back bay elements: DB BB UB BB BB DR DB ST UB ST ST DB EBB UB EBB EBBQ Q dt dV Q Q Q dt dV Q Q dt dV, , , (4-7) For Jupiter Inlet, the volume changes of the sand trap are approximated as zero because the sediment that flows into the tr ap is then dredged and placed within the system as nourishment on the beach. This means that, on average, accumulation of sand in the trap is not counted as a loss to the beach. Conse quently, the nourishment placed on the beach from the sand trap is eliminated from the equation as well because only

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42 nourishment coming from outside of the system needs to be accounted for. Also, the backbay element is approximated to be zero be cause the sediment that flows into, out of, and is stored in that region is relatively small when compared with the other elements, as shown in the last row of Table 4-1. Figure 4-1: Definition diag ram displaying Jupiter Inle t along with all possible components in the sediment budget equation Records of ebb shoal volumes tend to be lim ited and their reliability is uncertain. For this reason the sediment budget will be co mputed twice, once including the ebb shoal volume change rate data, and once assuming th e ebb shoal volume change rates to be negligible and therefore excl uding them from the equation. With all the necessary volumetric elemen ts being accounted for including the ebb shoal volume change rate, the excess (positive QDIFFERENCE value) or deficit (negative QIN (d V /d t )UB (d V /d t )DB QOUT QOS,UB QOS,DB QEBB,DB Q E BB,UB Q S T QNOUR,DB QNOUR,UB QBB Q D R,OFF

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43 QDIFFERENCE value) of nourishment on the downdrift beach of Jupiter Inlet is found based on the following equation: NOUR EBB UB DB DIFFERENCEQ dt dV dt dV dt dV Q 2 1 (4-8) It consists of only the volumetric rates of change occurring on the north and south beaches and in the ebb tidal shoal, as well as the volumet ric rate at which nourishment from outside of the system is placed on th e downdrift beach, as s hown in Figure 4-2. The sediment budget equation for Jupiter Inlet in which the ebb shoal volume change rate is excluded is similar to equati on (4-8) with the only difference being that it excludes the ebb shoal term as follows: NOUR UB DB DIFFERENCEQ dt dV dt dV Q 2 1 (4-9) Table 4-1: Annual mean sand volumetric tran sport rates in the eas tern zone (Source: Patra & Mehta, 2004, p. 11) Transport from/to Volumetric rate (m3/yr) Net southward littoral drift 176,000 Entering the channel from littoral drift 46,000 Bar-bypassed around the inlet 128,000 Bypassed by dredging from JIDa trap and ICWW 33,000 Tidally bypassed by entering and then leaving the channel 4,000 Ejected from the channel to offshore by ebb flowb 4,000 Transported offshore from drift by ebb flowb 2,000 Transported to ICWW channels north and south of inlet 4,000 Transported to central embayment 1,000 a Jupiter Inlet District. b Deposited seaward of the littoral system.

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44 Figure 4-2: Sediment budget compon ents specific to Jupiter Inlet 4.1.2 Method for Evaluating Sediment Budget In order to determine the rate of excess or deficit of nourishment being placed on the beach downdrift of Jupiter Inlet, several steps were follo wed. First, the beach profile data were collected from records available on the Florida Department of Environmental Protection’s website and from r ecords kept by the Jupiter Inle t District. The FDEP data were analyzed for two different shoreline dist ances updrift and downdrift of Jupiter Inlet. The first analysis conducted focused on a distance of 17.4 km north of the inlet, beginning at Monument R-75 in Martin Count y, and extending a di stance of 8.53 km south of the inlet, ending at Monument R40 in Palm Beach County. The second distance of shoreline that was analyzed covered equal distances of shoreline updrift and downdrift of the inlet, beginning at Monument R-112 in Martin County, 7.25 km nor th of the inlet, (d V /d t )UB (d V /d t )DB Q E BB,DB QEBB,UB QNOUR,DB

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45 and ending just past Monument R-36, 7.25 km s outh of the inlet. For each shoreline distance analyzed, the FDEP data were examined over three periods. The average periods were from 1974 to 1986, 1986 to 2002, and 1974 to 2002. These average periods were determined based on the survey da tes that were available for each county, specifically 1976, 1982 and 2002 for Martin County and 1974, 1990 and 2001 for Palm Beach County. The JID data were analyzed fo r a short shoreline distance within Palm Beach County, beginning at Monument R-10 whic h is almost 0.56 km north of the inlet, and ending at R-15 which is approximately 0.50 km south of the inlet. The JID data were analyzed for one period only, from 2001 to 2002. From these beach profile data, values of the cumulative volumetric rates of change of sediment being stored on the updrift and downdrift beaches, UBdt dV and DBdt dV respectively, for the defined distances and time periods were determined as described in Section 3.1. To calculate the rates of beach nourishment, records of nourishment on the updrift and downdrift beaches were collected. Because the sediment budget methodology is focused on analyzing the volumetric rates of change that occur on the downdrift beach and only accounts for changes that would o ccur naturally, nourishment on the updrift beach does not appear in the final sediment budget calculation. Therefore, volumetric rates of nourishment that had occurred on the beaches updrift of the inlet were subtracted from the values of volumetric rates of cha nge of sediment stored on the updrift beach. The records of nourishment on the downdrift beaches were added into the sediment budget equation as NOURQ in cases where the sediment used for nourishment came from outside of the beach system. The nourishment from outside of the beach system consisted mainly of sediment dredged from the Intracoastal Waterw ay deposition basin.

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46 The sediment collected in this basin is beli eved to have come from sources other than directly from the inlet, including the ch annel and the Loxahatchee River system. Volumes dredged from the JID sand trap and from the ebb tidal delta to be used as nourishment on the downdrift beach were not in cluded when calculating the final rates of nourishment in the sediment budget equation because both the sand trap and the delta were considered to be included in the system. Records of volume measurements of the ebb tidal shoal are scarce. Only one compilation of volume measurements was f ound (Dombrowski, 1994), and this included measurement estimations only through 1993. The early data show wide variability, and it is uncertain if this is due to volume changes actually experienced or due to limitations in the quality of surveys used to obtain the volum es. Three of the measurements relevant to the study time period were used to construct a best-f it trend line, as shown in Figure 4-3. The slope of this line displayed a slightly positive volumetric rate of change which was used as EBBdt dV in the sediment budget equation. Because there were very few reliable measurements, the ebb tidal shoa l volumetric rate of change was assumed to be constant as obtained from the best-fit line for all periods analyzed in the sediment budget. The 2000 and 2001 ebb tidal shoal survey da ta that were taken from the Palm Beach County Department of Environmental Resources Management website were also analyzed to find a volumetric rate of change estimate in order to assess the accuracy of the above estimate. A grid was created in MATLAB, and using measurements from the surveys, interpolations were made to find de pths at each point of the grid. From this depth-grid, contour plots were created for each year, as shown in Figures 4-4 and 4-5. As displayed in Figure 4-6, the 2000 depth elevations were then subtracted from the 2001

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47 Best-fit line with a slope of 4,285.7 depth elevations in order to find the differen ce in depths between th e two years. As the exact area of the ebb delta was uncertain, di fferent areas were used to calculate the volume changes. These areas are shown as boxes in Figure 4-6. Examining the area contained in the large box, a volume of -52,200 m3 was estimated, implying that the delta had eroded between 2000 and 2001. Adding toge ther the volumes estimated from the three smaller boxes, a to tal volume of +15,208 m3 was estimated, suggesting that the delta had accreted from 2000 to 2001. Based on these calculations, it is obvious that ebb tidal shoal volume estimates vary greatly in accordance with the assumption of the area that is considered to constitute the ebb shoal. This could explain the variability in the measurements that were found in Dombrowski (1994). It wa s also the reason that the sediment budgets were computed both with and without the e bb shoal component. Jupiter Inlet Ebb Delta Volumesy = 4285.7x 8E+06 0 100000 200000 300000 400000 500000 600000 700000 800000 1880190019201940196019802000 YearVolume (m^3) Figure 4-3: Plot showing meas urements of Jupiter Inlet’s eb b delta volumes, highlighting the three that were chosen to construct a best-fit line

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48 Figure 4-4: Jupiter Inlet ebb tidal shoal depth contours for the year 2000 Figure 4-5: Jupiter Inlet ebb tidal shoal depth contours for the year 2001

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49 Figure 4-6: Jupiter Inlet ebb tidal shoal difference in depth contours (2001-2000) used for volume calculations After deriving all of the volumetric quan tities for the necessary sediment budget components, these quantities were inserted in to the sediment budget equations derived in order to solve for DIFFERENCEQ The sediment budget components are presented in Tables 4-2, 4-3, and 4-4 with the appropr iate quantities inserted wher e required. As discussed in Chapter 2, the sediment budgets that were cr eated based on the FDEP profile data are presented as the “FDEP sediment budgets”, and the sediment budget that was created using the JID profile data is presented as the “JID sediment budget”. 4.1.3 Effect of Length of Beach on Sediment Budget Calculations The result of a sediment budget equation may vary depending on the equal lengths of updrift and downdrift shorelin e that are chosen for the an alysis. By selecting short distances of shoreline updrif t and downdrift of the inlet, the immediate effects on the

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50 downdrift beach caused by the inlet or by re cent nourishment events will be seen, whereas selecting larger distan ces of shoreline will display if and how the inlet affects the shoreline and beaches further downdrift. If the sediment budget analysis is carried out for a distance of shoreline covering downdr ift areas of shoreline where erosion is significant, the result of the sediment budget wi ll likely show a large deficit of sediment on the downdrift beach if the updr ift beach is not experiencing similar erosive trends. However, if the analysis covers a distance of shoreline that displays differing amounts of accretion and erosion, the result of the sedime nt budget will show a surplus or deficit of sediment on the downdrift beach dependent on whether the accretive or erosive trends dominate when compared with the updrift beach’s behavior. Specifically for Jupiter Inlet, if availabil ity of data allow, the minimum length of beach that should be chosen for analysis is approximately 1 km updrift and downdrift of the inlet. Since the length of the nourished beach downdrift of the inlet is nearly 0.5 km, a 1 km shoreline distance should be a suffici ent length with which to observe the effects of the natural spreadi ng of nourishment. Also, this shor eline distance is approximately four times the length of the jetty that is sout h of Jupiter Inlet, mean ing that the immediate effects of the inlet and its jetties should be evident within this proximity. 4.2 FDEP Sediment Budget Components As mentioned previously, two sediment budgets were developed based on the FDEP beach profile data with the only di fference between them being the length of shoreline included in the an alysis. Presented in Tabl e 4-2 are the sediment budget components for the long shoreline analysis which began at Monument R-75 in Martin County and extended southward to R-40 in Palm Beach County, covering approximately 26 km of shoreline. Table 4-2 presents the volume changes per year of the beaches

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51 downdrift and updrift of Jupiter In let, the volumetric rate of change of the ebb tidal shoal, and the volumetric rate of nourishment placed on the downdrift beach with sediment from outside of the system. The last two co lumns display the estimates of the excess or deficit of nourishment on the downdrift beach on a yearly basis for the given period, with the first including the ebb shoal volume estima tes as in Equation (4 -8) and the second excluding the ebb shoal volume estim ates as in Equation (4-9). Table 4-2: FDEP sediment budge t components for long analysis Period (dV/dt)DB (m3/yr) (dV/dt)UB (m3/yr) (dV/dt)EBB(m3/yr) QNOUR (m3/yr) QDIFFERENCE (Including ebb shoal volume estimates) (m3/yr) QDIFFERENCE (Excluding ebb shoal volume estimates) (m3/yr) 19741986 800 -206,700 4,300 18,500 110,900 113,000 19862002 152,700 -142,400 4,300 24,300 157,600 159,700 19742002 55,300 -173,200 4,300 20,900 122,600 124,700 The second FDEP sediment budget estimate, which is the more accurate of the two FDEP budgets, is based on the short shorelin e analysis which began at Monument R-112 in Martin County and extended southward just past R-36 in Palm Beach County. This budget is more accurate because it analyzes equal distances of shoreline updrift and downdrift of the inlet, each 7.25 km in length, which is appropriate according to the basis of the sediment budget equation. As stated, accord ing to this basis, in the absence of an inlet, the volume changes over the same distances of shoreline updrift and downdrift should be equal. The sediment budget compone nts for this analysis are presented in Table 4-3 in the same order as in Table 4-2.

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52 Table 4-3: FDEP sediment budge t components for short analysis Period (dV/dt)DB (m3/yr) (dV/dt)UB (m3/yr) (dV/dt)EBB(m3/yr) QNOUR (m3/yr) QDIFFERENCE (Including ebb shoal volume estimates) (m3/yr) QDIFFERENCE (Excluding ebb shoal volume estimates) (m3/yr) 19741986 6,900 1,000 4,300 18,500 10,100 12,200 19862002 114,300 20,900 4,300 24,300 56,700 58,900 19742002 47,000 4,700 4,300 20,900 29,500 31,600 4.3 JID Sediment Budget Components The sediment budget based on the data provid ed by JID is presented in Table 4-4. This analysis covers a small distance of ju st over 1 km of shoreline and extends from Monument R-10 in Palm Beach County, north of th e inlet, to R-15, south of the inlet. Consistent with both of the FDEP analyses it can be seen that the downdrift beach volume change rate is positive. Table 4-4: JID sediment budget components Period (dV/dt)DB (m3/yr) (dV/dt)UB (m3/yr) QEBB (m3/yr) QNOUR (m3/yr) QDIFFERENCE (Including ebb shoal volume estimates) (m3/yr) QDIFFERENCE(Excluding ebb shoal volume estimates) (m3/yr) August 2001October 2002 83,300 -2,600 4,300 49,600 65,600 67,800 4.4 Sediment Budget Results The equations developed in Section 4.1 provi de the basis for the calculation of the excesses or deficiencies in nourishment on th e downdrift beach that prevent the balance of the sediment budget. If the sedime nt budget were balanced, the value of QDIFFERENCE

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53 would be equal to zero. A QDIFFERENCE value that is negative corresponds to a need for additional nourishment whereas a value that is positive means that more sediment exists on the downdrift beach than is needed for the volume changes on the updrift and downdrift beaches to balance ou t. According to the short FDEP analysis presented in Table 4-3, over the long-term pe riod of 1974-2002 an excess of 29,500 m3/yr of sediment existed on the downdrift beach when the ebb s hoal volume estimates were included in the analysis, and an excess of 31,600 m3/yr existed on the downdrift beach when the ebb shoal volume estimates were excluded. The tw o shorter periods includ ed within the total period also display excess volumes on the downdrif t beach and can be seen in the last two columns of Table 4-3. According to the JID sediment budget analysis presented in Table 4-4, between August 2001 and October 2002 an excess of 65,600 m3/yr of sediment existed on the downdrift beach when the ebb s hoal volume estimates were included in the analysis, and an excess of 67,800 m3/yr existed on the downdrift beach when the ebb shoal volume estimates were excluded. These positive quantities support the results of the FDEP sediment budget estimates. The sediment budget results are summarized in Table 4-5. Table 4-5: Short FDEP a nd JID sediment budget results Sediment Budget QDIFFERENCE (Including ebb shoal volume estimates) (m3/yr) QDIFFERENCE (Excluding ebb shoal volume estimates) (m3/yr) Short FDEP 29,500 31,600 JID 65,600 67,800

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54 CHAPTER 5 SUMMARY AND CONCLUSIONS 5.1 Summary Due to the shoaling of Jupite r Inlet, a tidal entrance along the southeastern coast of Florida, and the resulting erosion of its adja cent beaches since its stabilization, there has been an extensive history of dredging of the inlet’s sand trap and nourishment of the downdrift beach. The implementation of a ma nagement plan in 1992 has made specific criteria to be followed in order to control the shoaling within the inlet and to minimize surrounding beach erosion. The objective of th is study was to develop a sediment budget taking into account sediment-storing component s relevant to Jupite r Inlet in order to assess the role of downdrift beach nourishment. In order to perform this study, beach profile data were compiled from two sources, the Florida Department of Environmental Prot ection (FDEP) and the Jupiter Inlet District (JID). Additional data collected fo r the sediment budgets included dredging, nourishment and ebb shoal data. The data collected for the FDEP sediment budgets were examined for three time periods, covering 1974 to 1986, 1986 to 2002 and 1974 to 2002. The JID survey data that were examined covered time periods of 1995 to 1996, 1996 to 1997, and 1995 to 2004 for Monuments R-13 to R17 downdrift of the inlet, and a period of 2001 to 2002 for Monuments R-10 to R-21. From the beach profile data, shoreline changes and sediment volume changes over the selected periods of time were calculated for the beaches updrift and downdrift of the inlet. These calculations took into account profile data unc ertainties. Volume change

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55 sensitivity to the assumed depths of closure was also examined. The shoreline and sediment volume changes were calculated for Monuments R-75 to R-127 between 1976 and 1982, 1982 and 2002, and 1976 and 2002 for Martin County and for Monuments R-1 to R-40 between 1974 and 1990, 1990 and 2001, and 1974 and 2001 for Palm Beach County based on the FDEP profile data. The sa me sets of calculations were made for Monuments R-13 to R-17, just downdrift of the inlet between May 1995 and May 1996, May 1996 and March 1997, and May 1995 and April 2004 and for Monuments R-10 to R-21 between August 2001 and October 2002 based on the JID profile data. The basis of the development of the sediment budget was that volume changes over the same distances of shoreline updrift and dow ndrift of the inlet would be identical in the absence of the inlet, and therefore a sediment balance co uld be created based on this principle (Dean, 2005). 5.2 Conclusions 1. Based on the shoreline change calculations made from the FDEP profile data, although both shoreline advancement and rece ssion occur, the overall trend is seen to be shoreline advancement downdrift of the inlet. 2. Based on the volume change calculations made from the FDEP profile data, the areas of shoreline displaying volumetric a ccretion outnumber the areas of shoreline displaying erosion on the beach downdrift of the inlet. 3. The shoreline change rates based on the 1995, 1996, 1997 and 2004 JID profile data taken downdrift of Jupiter Inlet show varying shoreline advancement and recession for the first two intervals (1995-1996 and 1996-1997), but the shoreline changes display recession for the last in terval (1995-2004). The shoreline change rates calculated based on the JID prof ile data between August 2001 and October 2002 display high rates of accr etion on the downdrift beach, with erosion occurring only at Monument R-20. 4. The volume change rates based on the 1995, 1996, 1997 and 2004 JID profile data taken downdrift of Jupiter Inlet display mainly volumetric erosion. The volume change rates calculated based on the JI D profile data between August 2001 and October 2002 display high rates of accre tion on the downdrift beach, with erosion occurring only at Monument R-20.

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56 5. There is substantial variability in the results of the sediment budgets depending on whether or not ebb tidal deltas are included in the calculations. When the ebb tidal delta volume changes were excluded from the calculations, the results of all sediment budgets were about 2,100 m3 per year higher than when they were included in the calculations. Also, the va riability within the sediment budgets is dependent on which ebb tidal delta volume estimations are assumed to accurate and used in the calculations. As discussed in Chapter 4, depending on the area chosen as the ebb tidal delta, the volume change estimations vary greatly, ranging from high rates of accretion to high rates of erosion. 6. Volume change rates showed only slight sens itivities to the dept h of closure chosen for the calculations. The largest sensitivity calculated showed an average difference between rates was 1.68 m3/m per year. Most other calculations showed average differences between rates to be less than 1 m3/m per year. These sensitivities are due to the fact that th e distance to the dept h of closure alters depending on the depth of closure chosen, and the distance to this depth is the seaward extent of th e volume calculations. 7. For the sediment budgets developed, the consistent result was that over all time periods considered there has been an ex cess amount of sediment existing on the downdrift beach when compared with approxi mately the same shoreline distance of beach updrift of the inlet. Two of the three sediment budgets that were created are more accurate based on the fact that th ey analyze nearly equal distances of shoreline updrift and downdr ift of the inlet. Thes e two budgets are the short “FDEP sediment budget” and the “JID sediment budget”. a. When ebb tidal delta volume estimates were excluded from the budget, overall excesses in sediment on the downdrift beach based on the short “FDEP sediment budget” from 1974 to 2002 were 31,600 m3/yr. Based on an average seaward distance of 250 m over a 7.25 km distance of shoreline, this result repr esents an average accreti on rate of just 1.74 cm/yr over the entire area. b. When ebb tidal delta volume estimates were excluded from the budget, overall excesses in sediment on the downdrift beach based on the “JID sediment budget” from August 2001 to October 2002 were 67,800 m3/yr. Based on an average seaward distan ce of 250 m over a 500 m distance shoreline, this result re presents an average accr etion rate of about 0.54 m/yr over the entire area. c. When ebb tidal delta volume estimat es were included in the budget, overall excesses in sediment on the downdrift beach based on the short “FDEP sediment budget” from 1974 to 2002 were 29,500 m3/yr. Based on an average seaward distance of 250 m over a 7.25 km distance of shoreline, this result re presents an average accr etion rate of only 1.63 cm/yr over the entire area.

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57 d. When ebb tidal delta volume estimat es were included in the budget, overall excesses in sediment on the downdrift beach based on the “JID sediment budget” from August 2001 to October 2002 were 65,600 m3/yr. Based on an average seaward distance of 250 m over a 500 m distance of shoreline, this result re presents an average accr etion rate of about 0.53 m/yr over the entire area. 5.3 Recommendations for Further Work In order to increase the accu racy of future sediment budget analyses, the following recommendations should be considered: 1. Profile survey data should be taken yearly of Monuments R-3 to R-21 so that there are nearly equal shoreline distances updrif t and downdrift of Jup iter Inlet. Equal shoreline distances increase sediment budget accuracy. In addition, by having survey data from each year, a more accura te rate of accretion or erosion can be determined. Also, rates that might seem unnaturally high or low could be linked to certain storm events or weather patterns that might go unnoticed when there is a much longer period of time in between surveys. 2. Regular surveys of the ebb tidal delta need to be taken yearly as well, preferably near the same time that the aforesaid profile surveys are taken. The area that the ebb tidal delta covers needs to be defined so that the yearly measurements can be taken in consistent locations, thus mi nimizing the resulting volume calculation discrepancies.

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58 APPENDIX A FDEP LONG BEACH PROFILES FOR MARTIN AND PALM BEACH COUNTIES Figure A-1: Profiles for M onument R-75 in Martin County.

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59 Figure A-2: Profiles for M onument R-78 in Martin County. Figure A-3: Profiles for M onument R-81 in Martin County.

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60 Figure A-4: Profiles for M onument R-84 in Martin County. Figure A-5: Profiles for M onument R-87 in Martin County.

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61 Figure A-6: Profiles for M onument R-90 in Martin County. Figure A-7: Profiles for M onument R-93 in Martin County.

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62 Figure A-8: Profiles for M onument R-96 in Martin County. Figure A-9: Profiles for M onument R-99 in Martin County.

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63 Figure A-10: Profiles for Monument R-102 in Martin County. Figure A-11: Profiles for Monument R-105 in Martin County.

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64 Figure A-12: Profiles for Monument R-108 in Martin County. Figure A-13: Profiles for Monument R-111 in Martin County.

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65 Figure A-14: Profiles for Monument R-114 in Martin County. Figure A-15: Profiles for Monument R-117 in Martin County.

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66 Figure A-16: Profiles for Monument R-120 in Martin County. Figure A-17: Profiles for Monument R-123 in Martin County.

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67 Figure A-18: Profiles for Monument R-126 in Martin County. Figure A-19: Profiles for Monument R-1 in Palm Beach County.

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68 Figure A-20: Profiles for Monument R-3 in Palm Beach County. Figure A-21: Profiles for Monument R-6 in Palm Beach County.

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69 Figure A-22: Profiles for Monument R-9 in Palm Beach County. Figure A-23: Profiles for Monument R-12 in Palm Beach County.

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70 Figure A-24: Profiles for Monument R-15 in Palm Beach County. Figure A-25: Profiles for Monument R-18 in Palm Beach County.

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71 Figure A-26: Profiles for Monument R-21 in Palm Beach County. Figure A-27: Profiles for Monument R-24 in Palm Beach County.

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72 Figure A-28: Profiles for Monument R-27 in Palm Beach County. Figure A-29: Profiles for Monument R-30 in Palm Beach County.

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73 Figure A-30: Profiles for Monument R-33 in Palm Beach County. Figure A-31: Profiles for Monument R-36 in Palm Beach County.

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74 Figure A-32: Profiles for Monument R-39 in Palm Beach County.

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75 APPENDIX B JID BEACH PROFILES FOR PALM BEACH COUNTY Figure B-1: Profiles for Monum ent R-10 in Palm Beach County.

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76 Figure B-2: Profiles for Monum ent R-11 in Palm Beach County. Figure B-3: Profiles for Monum ent R-12 in Palm Beach County.

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77 Figure B-4: Profiles for Monum ent R-13 in Palm Beach County. Figure B-5: Profiles for Monum ent R-14 in Palm Beach County.

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78 Figure B-6: Profiles for Monum ent R-15 in Palm Beach County. Figure B-7: Profiles for Monum ent R-16 in Palm Beach County.

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79 Figure B-8: Profiles for Monum ent R-17 in Palm Beach County. Figure B-9: Profiles for Monum ent R-18 in Palm Beach County.

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80 Figure B-10: Profiles for Monument R-19 in Palm Beach County. Figure B-11: Profiles for Monument R-20 in Palm Beach County.

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81 Figure B-12: Profiles for Monument R-21 in Palm Beach County.

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82 APPENDIX C STORMS NEAR JUPITER INLET, FLORIDA Table C-1 contains storms that occurred w ithin a vicinity of approximately 150 km of Jupiter Inlet between 1974 and 2004. The st orm data was obtained from the National Oceanic and Atmospheric Administration ( NOAA) website. The shoreline and volume changes that were calculated from the profile survey data and presented in Chapter 3 showed no effects of these storms because the dates in which the storms occurred did not correspond with the dates in which the surveys we re taken. If survey data were available from the same years that the storms occurre d, then it is possible th at the effects of the storms would be noticeable in the sh oreline and volume change calculations. Table C-1: Storms occurring wi thin 150 km of Jupiter Inlet Year Storm Name Storm Classification 1976 Dottie Tropical Storm 1979 David Hurricane 1983 Barry Hurricane 1984 Diana Hurricane 1984 Isidore Tropical Storm 1985 Bob Tropical Storm 1987 Floyd Hurricane 1988 Chris Tropical Storm 1988 Keith Tropical Storm 1991 Ana Tropical Storm 1992 Andrew Hurricane 1994 Gordon Hurricane 1995 Erin Hurricane 1995 Jerry Tropical Storm 1999 Harvey Tropical Storm 1999 Irene Hurricane 2004 Charley Hurricane 2004 Frances Hurricane 2004 Jeanne Hurricane

PAGE 95

83 LIST OF REFERENCES ALBADA, E., and CRAIG, K., 2006. Jupiter/Ca rlin shore protection project, Palm Beach County, Florida 24 month monito ring report. Report for Palm Beach County, Florida. AUBREY, D.G., and DEKIMPE, N.M., 1988. Performance of beach nourishment at Jupiter Island, Florida. Proceedings of the Beach Preservation Technology ’88 Conference L.S. Tait (ed.), Florida Shore and Beach Preservation Association, Tallahassee, Florida, 409-420. BUCKINGHAM, W. T., 1984. Coasta l engineering investigation at Jupiter Inlet, Florida. MS thesis. Coastal and Oceanographic E ngineering Department, University of Florida, Gainesville, Florida, 228p. DEAN, R.G., 2005. Analysis of the effect of Sebastian Inlet on adjacent beach systems using DEP surveys and coastal engineering principles. UFL/COEL-2005/003, Civil and Coastal Engineering Department, Univer sity of Florida, Gainesville, Florida, 22p, plus appendices. DEAN, R.G., and DALRYMPLE, R.A., 2002. Coastal Processes with Engineering Applications. Cambridge: Cambridge University Press. DOMBROWSKI, M.R., 1994. Ebb tidal delta evol ution and navigability in the vicinity of coastal inlets. MS thesis. Coasta l and Oceanographic Engineering Department, University of Florida, Gainesville, Florida, 95p. DOMBROWSKI, M.R., and MEHTA, A.J., 1993. Inlets and manage ment practices: southeast coast of Florida. Journal of Coastal Research, Special Issue18, A.J. Mehta (ed.), The Coastal Educati on and Research Foundation, 29-57. GRELLA, M. J., 1993. Development of management policy at Jupiter Inlet, Florida: An integration of technical analys es and policy constraints. Journal of Coastal Research Special Issue 18, A.J. Mehta (ed.), The Coastal Education and Research Foundation, 239-256. MEHTA, A.J.; GRELLA, M.J.; GANJU, N.K.; and PARAMYGIN, V.A., 2005. Sediment management in estuarie s: The Loxahatchee, Florida. Port and Coastal Engineering, P. Bruun (ed.), The Coastal Education and Research Foundation, West Palm Beach, Florida, 276-303.

PAGE 96

84 PATRA, R.R., 2003. Sediment management in low energy estuaries: The Loxahatchee, Florida. MS thesis. Civil and Coastal Engineering Department, University of Florida, Gainesville, Florida, 116p. PATRA, R.R., and MEHTA, A.J., 2004. Sediment ation issues in low-energy estuaries: The Loxahatchee, Florida. UFL/COEL-2004/002 Civil and Coastal Engineering Department, University of Flor ida, Gainesville, Florida, 40p. RODRIGUEZ, E., and DEAN, R.G., 2005. Se diment budget analysis and management strategy for Fort Pierce Inlet, Florida. UFL/COEL-2005/004 Civil and Coastal Engineering Department, University of Fl orida, Gainesville, Florida, 103p, plus appendices. STAUBLE, D.K., 1993. An overview of s outheast Florida inlet morphodynamics. Journal of Coastal Research, Special Issue 18, A.J. Mehta (ed.), The Coastal Education and Research Foundation, 1-27. TABAR, J.R.; UTKU, M.; and SPURGEON, J.R ., 2002. Town of Jupiter Island, Florida, beach renourishment project performance evaluation. Proceedings 2002 National Conference on Beach Preservation Technology, L. Tait (ed.), Florida Shore and Beach Preservation Association, Tallahassee, Florida, 71-89.

PAGE 97

85 BIOGRAPHICAL SKETCH Kristen Marie Odroniec was born in Michigan in 1982 to Karen and Stan Odroniec. When she was ten years old, th e author’s family moved to Florida, where she developed an interest in the nearby beach and coastline. Upon completion of high school in 2000, she moved to Gainesville, where she pursued a Bachelor of Science degree in civil engineering at the University of Florida. Kristen graduated in December 2004, and she entered the Coastal and Oceanographic Engineer ing Program at the University of Florida in January of 2005. After obtaining her Master of Science degree in coastal engineering, Kristen plans to join the i ndustry as a coastal engineer.


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Physical Description: Mixed Material
Copyright Date: 2008

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Table of Contents
    Title Page
        Page i
    Acknowledgement
        Page ii
    Table of Contents
        Page iii
        Page iv
        Page v
    List of Tables
        Page vi
    List of Figures
        Page vii
        Page viii
        Page ix
        Page x
    Abstract
        Page xi
        Page xii
    Introduction
        Page 1
        Page 2
    Site description and database
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
    Shoreline and beach volume changes
        Page 15
        Page 16
        Page 17
        Page 18
        Page 19
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        Page 21
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    Sediment budget
        Page 39
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        Page 44
        Page 45
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    Summary and conclusions
        Page 54
        Page 55
        Page 56
        Page 57
    Appendices
        Page 58
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        Page 81
        Page 82
    References
        Page 83
        Page 84
    Biographical sketch
        Page 85
Full Text












COASTAL SEDIMENT BUDGET FOR
JUPITER INLET, FLORIDA














By

KRISTEN MARIE ODRONIEC


A THESIS PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
MASTER OF SCIENCE

UNIVERSITY OF FLORIDA


2006















ACKNOWLEDGMENTS

I greatly thank my supervisory committee, Dr. Ashish Mehta, Dr. Robert Dean, and

Dr. Andrew Kennedy, for their assistance, guidance and insight throughout this research

project. I would also like to express my gratitude to the Jupiter Inlet District for

providing the financial resources needed to carry out this project. Thanks also go to

Michael Grella of the Jupiter Inlet District for always providing prompt answers to my

many questions and requests for information.

I would also like to thank all of my fellow coastal engineering students and friends,

whose support and distraction kept me sane. Finally, my ultimate thanks go to my family

who were always there for me providing patience, understanding, encouragement and

love.
















TABLE OF CONTENTS



A C K N O W L E D G M E N T S .................................................................................................. ii

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

LIST OF FIGURES ............................. ............ .................................... vii

ABSTRACT .................................................... ................. xi

CHAPTER

1 IN TR O D U C T IO N ........ .. ......................................... ..........................................1.

1.1 P problem Statem ent .. ................................................................. .................
1.2 O objective and Tasks ......................................................................... ......... .. 1
1.3 O utline of C hapters ......................................... .. ....................... .... ......... ... 2

2 SITE DESCRIPTION AND DATABASE.............................................. ...............3...

2.1 Site D description and R recent H istory.................................................. ...............3...
2.1.1 Site D description .............. ...... ............ ..............................................3....
2.1.2 R recent H history .............. .... ............. .................................................. 4
2.3 B each Profile D ata ..... ................................................................... ... ......... .. .7
2 .4 E bb Shoal V olum e D ata ......................................... ........................ ...............9...
2 .5 D dredging D ata................................................... .......................................... . 9
2.6 Beach N ourishm ent D ata....................................... ................................... 10
2.6.1 Downdrift Beach Nourishment Volumes ............................................. 10
2.6.2 Updrift Beach Nourishment Volumes.............. .................................... 14

3 SHORELINE AND BEACH VOLUME CHANGES...........................................15

3.1 Shoreline and Beach Volume Change Calculation Methods.............................. 15
3.2 D ata Lim stations and U uncertainties ................................................. ................ 16
3.2 .1 D ata U uncertainties ............................................. ... .............. ............... 17
3.2.2 Corrections for Non-Closure of Profiles ............................... ................ 18
3.2.3 Corrections for M monument Relocation.................................. ............... 19
3.3 FD EP Intersurvey Interval: 1974-1986 .......................................... ................ 19
3.3.1 Shoreline C changes ........................................................ ............ ............ 20
3.3.2 Sedim ent V olum e Changes ................................................... 20









3.4 FDEP Intersurvey Interval: 1986-2002 .......................................... ................ 21
3.4.1 Shoreline C changes ..................................... .. ............ ............ ............ 21
3.4.2 Sedim ent V olum e Changes ................................................... ................ 22
3.5 FDEP Intersurvey Combined Interval: 1974-2002.........................................23
3.5.1 Shoreline C changes ....................................... .. .......... ............ ............ 23
3.5.2 Sedim ent V olum e Changes ................................................... ................ 24
3.6 Volume Change Sensitivity to Depth of Closure ............................................27
3.6.1 Volume Change Sensitivity to Depth of Closure: 1974 to 1986 ............28
3.6.2 Volume Change Sensitivity to Depth of Closure: 1986 to 2002 ............29
3.6.3 Volume Change Sensitivity to Depth of Closure: 1974 to 2002 ............30
3.7 JID Intersurvey Interval: 1995-1996 ................................................... 31
3.7.1 Shoreline C changes ..................................... .. ............ ............ ............ 32
3.7.2 Sedim ent V olum e Changes ................................................... ................ 32
3.8 JID Intersurvey Interval: 1996-1997 ................................................... 32
3.8.1 Shoreline C changes ..................................... .. ............ ............ ............ 32
3.8.2 Sedim ent V olum e C changes ................................................... ................ 33
3.9 JID Intersurvey Combined Interval: 1995-2004.............................................33
3.9.1 Shoreline C changes ..................................... .. ............ ............ ............ 33
3.9.2 Sedim ent V olum e C changes ................................................... ................ 33
3.10 JID Intersurvey Interval: 2001-2002 ............................................ ................ 34
3.10.1 Shoreline C changes ...................................... ...................... ................ 34
3.10.2 Sedim ent V olum e Changes ................................................. ................ 34

4 SED IM EN T B U D G E T ...................................................................... ................ 39

4.1 Sedim ent B budget M ethodology ....................................................... ................ 39
4.1.1 Sedim ent B budget E quation .................................................... ................ 39
4.1.2 Method for Evaluating Sediment Budget......................... ................ 44
4.1.3 Effect of Length of Beach on Sediment Budget Calculations.................49
4.2 FDEP Sedim ent Budget Com ponents.............................................. ................ 50
4.3 JID Sedim ent Budget Com ponents.................................................. ................ 52
4.4 Sedim ent B budget R results .................................... ....................... ................ 52

5 SUM M ARY AND CONCLU SION S.................................................... ................ 54

5 .1 S u m m ary .............................................................................................................. 5 4
5.2 C onclu sions ................................................. . .... ..... ........... ............... 55
5.3 Recom m endations for Further W ork............................................... ............... 57

APPENDIX

A FDEP LONG BEACH PROFILES FOR MARTIN AND PALM BEACH
C O U N T IE S ............................................................................................................... .. 5 8

B JID BEACH PROFILES FOR PALM BEACH COUNTY ..................75

C STORMS NEAR JUPITER INLET, FLORIDA...................................................82










L IST O F R EFER EN CE S ...... .................................................................... ................ 83

BIO GR APH ICAL SK ETCH ...................... .............................................................. 85


























































v















LIST OF TABLES


Table page

2-1 Beach profile data for Martin and Palm Beach Counties.....................................8...

2-2 Jupiter Inlet ebb shoal volumes (Source: Dombrowski, 1994)..............................9...

2-3 Jupiter Inlet and interior sand trap dredging volumes.........................................10

2-4 Jupiter Inlet downdrift beach nourishment volumes...........................................12

2-5 Jupiter Inlet updrift beach nourishment volumes................................................14

4-1 Annual mean sand volumetric transport rates in the eastern zone (Source: Patra
& M ehta, 2004, p. 11) ............. ............... ................................................. 43

4-2 FDEP sediment budget components for long analysis........................................51

4-3 FDEP sediment budget components for short analysis......................................52

4-4 JID sedim ent budget com ponents ....................................................... ................ 52

4-5 Short FDEP and JID sediment budget results .....................................................53

C-1 Storms occurring within 150 km of Jupiter Inlet ................................................82
















LIST OF FIGURES


Figure page_

2-1 Jupiter Inlet connecting the Loxahatchee River forks to the Atlantic Ocean ..........3...

2-2 FDEP range monuments north and south of Jupiter Inlet ....................................5...

2-3 A rea m ap of Jupiter Inlet........................................... ......................... ...............6...

2-4 Photograph of Jupiter Inlet showing jetties and approximate location of sand
trap ........................................................................................................... ......... 6

2-5 Jupiter Inlet Management Plan recommended increase in nourishment beach
len g th ...................................................................................................... ........ .. 13

2-6 Sand trap and Intracoastal Waterway deposition basin from which sediment is
dredged to be used as nourishm ent ................................................... 13

3-1 Schematic diagram defining depth of closure, where all offshore profiles
converge to a certain depth ........................................ ....................... ............... 18

3-2 Shoreline change rates for the period from 1976 to 1982 in Martin County and
from 1974 to 1990 in Palm Beach County.......................................... ................ 24

3-3 Unit volume change rates for the period from 1976 to 1982 in Martin County
and from 1974 to 1990 in Palm Beach County ................................... ................ 25

3-4 Shoreline change rates for the period from 1982 to 2002 in Martin County and
from 1990 to 2001 in Palm Beach County.......................................... ................ 25

3-5 Unit volume change rates for the period from 1982 to 2002 in Martin County
and from 1990 to 2001 in Palm Beach County ................................... ................ 26

3-6 Shoreline change rates for the combined period from 1976 to 2002 in Martin
County and from 1974 to 2001 in Palm Beach County ......................................26

3-7 Unit volume change rates for the combined period from 1976 to 2002 in Martin
County and from 1974 to 2001 in Palm Beach County ......................................27

3-8 Unit volume change rates calculated with varying depths of closure for the
period from 1976 to 1982 in Martin County and from 1974 to 1990 in Palm
B each C ou n ty ........................................................................................................... 2 9









3-9 Unit volume change rates calculated with varying depths of closure for the
period from 1982 to 2002 in Martin County and from 1990 to 2001 in Palm
B each C ou n ty ........................................................................................................... 3 0

3-10 Unit volume change rates calculated with varying depths of closure for the
combined period from 1976 to 2002 in Martin County and from 1974 to 2001 in
Palm Beach County .................................................................... 31

3-11 Shoreline change rates for the period from 1995 to 1996 just south of Jupiter
Inlet in Palm B each C county ...................................... ....................... ................ 35

3-12 Unit volume change rates for the period from 1995 to 1996 just south of Jupiter
Inlet in Palm B each C county ...................................... ....................... ................ 35

3-13 Shoreline change rates for the period from 1996 to 1997 just south of Jupiter
Inlet in Palm B each C county ...................................... ....................... ................ 36

3-14 Unit volume change rates for the period from 1996 to 1997 just south of Jupiter
Inlet in Palm B each C county ...................................... ....................... ................ 36

3-15 Shoreline change rates for the combined period from 1995 to 2004 just south of
Jupiter Inlet in Palm B each C ounty..................................................... ................ 37

3-16 Unit volume change rates for the combined period from 1995 to 2004 just south
of Jupiter Inlet in Palm B each County ................................................ ................ 37

3-17 Shoreline change rates for the period from 2001 to 2002 in Palm Beach County ...38

3-18 Unit volume change rates for the period from 2001 to 2002 in Palm Beach
C o u n ty .................................................................................................................. ... 3 8

4-1 Definition diagram displaying Jupiter Inlet along with all possible components
in the sedim ent budget equation.......................................................... ................ 42

4-2 Sediment budget components specific to Jupiter Inlet....................................... 44

4-3 Plot showing measurements of Jupiter Inlet's ebb delta volumes, highlighting
the three that were chosen to construct a best-fit line .........................................47

4-4 Jupiter Inlet ebb tidal shoal depth contours for the year 2000 .................................48

4-5 Jupiter Inlet ebb tidal shoal depth contours for the year 2001 ...............................48

4-6 Jupiter Inlet ebb tidal shoal difference in depth contours (2001-2000) used for
volum e calculations .............. ................. .................................................. 49

A-i Profiles for Monument R-75 in Martin County ..................................................58

A-2 Profiles for Monument R-78 in Martin County ..................................................59









A-3 Profiles for Monument R-81 in Martin County ..................................................59

A-4 Profiles for Monument R-84 in Martin County ..................................................60

A-5 Profiles for Monument R-87 in Martin County ..................................................60

A-6 Profiles for Monument R-90 in Martin County ..................................................61

A-7 Profiles for Monument R-93 in Martin County ..................................................61

A-8 Profiles for Monument R-96 in Martin County ..................................................62

A-9 Profiles for Monument R-99 in Martin County ..................................................62

A-10 Profiles for Monument R-102 in Martin County ...............................................63

A-11 Profiles for Monument R-105 in Martin County ...............................................63

A-12 Profiles for Monument R-108 in Martin County ...............................................64

A-13 Profiles for Monument R- 111 in Martin County ...............................................64

A-14 Profiles for Monument R-114 in Martin County ...............................................65

A-15 Profiles for Monument R-117 in Martin County ...............................................65

A-16 Profiles for Monument R-120 in Martin County ...............................................66

A-17 Profiles for Monument R-123 in Martin County ...............................................66

A-18 Profiles for Monument R-126 in Martin County ...............................................67

A-19 Profiles for Monument R-1 in Palm Beach County ...........................................67

A-20 Profiles for Monument R-3 in Palm Beach County ...........................................68

A-21 Profiles for Monument R-6 in Palm Beach County ...........................................68

A-22 Profiles for Monument R-9 in Palm Beach County ...........................................69

A-23 Profiles for Monument R-12 in Palm Beach County ..........................................69

A-24 Profiles for Monument R-15 in Palm Beach County ..........................................70

A-25 Profiles for Monument R-18 in Palm Beach County ..........................................70

A-26 Profiles for Monument R-21 in Palm Beach County ..........................................71

A-27 Profiles for Monument R-24 in Palm Beach County ..........................................71









A-28 Profiles for Monument R-27 in Palm Beach County ............... ............... 72

A-29 Profiles for Monument R-30 in Palm Beach County ............... ............... 72

A-30 Profiles for Monument R-33 in Palm Beach County ............... ............... 73

A-31 Profiles for Monument R-36 in Palm Beach County ............... ............... 73

A-32 Profiles for Monument R-39 in Palm Beach County ............... ............... 74

B-i Profiles for Monument R-10 in Palm Beach County ............... ............... 75

B-2 Profiles for Monument R-11 in Palm Beach County ............... ............... 76

B-3 Profiles for Monument R-12 in Palm Beach County ............... ............... 76

B-4 Profiles for Monument R-13 in Palm Beach County ............... ............... 77

B-5 Profiles for Monument R-14 in Palm Beach County ............... ............... 77

B-6 Profiles for Monument R-15 in Palm Beach County ............... ............... 78

B-7 Profiles for Monument R-16 in Palm Beach County ............... ............... 78

B-8 Profiles for Monument R-17 in Palm Beach County ............... ............... 79

B-9 Profiles for Monument R-18 in Palm Beach County ............... ............... 79

B-10 Profiles for Monument R-19 in Palm Beach County ............... ............... 80

B-11 Profiles for Monument R-20 in Palm Beach County ............... ............... 80

B-12 Profiles for Monument R-21 in Palm Beach County ............... ............... 81















Abstract of Thesis Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Master of Science

COASTAL SEDIMENT BUDGET FOR
JUPITER INLET, FLORIDA

By

Kristen Marie Odroniec

December 2006

Chair: Andrew Kennedy
Major: Coastal and Oceanographic Engineering

Three sediment budgets have been developed for Jupiter Inlet, a tidal entrance that

connects the Atlantic Ocean to the Loxahatchee River in southeast Florida. These

budgets cover varying lengths of shoreline updrift and downdrift of the inlet and are

based on two sources of survey data.

Two of the three budgets are based on Florida Department of Environmental

Protection (FDEP) profile surveys covering periods of 1974 to 1986, 1986 to 2002, and

1974 to 2002. The third budget is based on surveys provided by the Jupiter Inlet District

(JID) and covers the period of August 2001 to October 2002. The first budget covers a

shoreline distance of approximately 26 km. The total period of 1974 to 2002 shows a net

accumulation of sediment on the 8.53 km long downdrift beach of 122,600 m3 per year.

Since the shoreline distances north and south of the inlet are not equal, this sediment

budget was believed to be the least accurate of the three. The second budget covers a

shoreline distance of 14.5 km. This budget is believed to be more accurate in the respect









that it covers equal distances of north and south shorelines. It was determined that from

1974 to 2002 there has been a net accumulation of sediment on the 7.25 km long

downdrift beach of 29,500 m3 per year. The third budget covers a shoreline distance of

about 1 km, with nearly equal distances north and south of the inlet. From August 2001

to October 2002, there has been a net accumulation of sediment on the downdrift beach

of 65,600 m3 per year. Due to the variability in the available ebb tidal delta volume data,

two calculations of each of the three sediment budgets were made, one including delta

volume change estimates and one excluding these estimates. The volumes given include

the delta volume change estimates. When these changes are excluded from the

calculations, net accumulated sediment volumes on the downdrift beach are about 2,100

m3 per year higher than those given.

It is recommended that profile survey data be taken yearly for Palm Beach County

Monuments R-3 to R-21, which cover approximately equal shoreline distances updrift

and downdrift of the inlet. Also, the area that the ebb tidal delta covers should be

identified and also surveyed on a yearly basis.














CHAPTER 1
INTRODUCTION

1.1 Problem Statement

Tidal inlets provide navigational access from the ocean to lagoons or bays for

commercial and recreational purposes, and they also allow for the necessary exchange of

waters, thus maintaining water quality and promoting life. However, some of the

sediment that is transported along the coast often becomes trapped in the inlet channel

during the flood tide and some is jetted far offshore during the ebb tide rather than being

deposited on the shore as would normally occur in the absence of an inlet. This

interruption in the longshore sediment transport causes shoreline erosion at beaches

adjacent to the inlet (Dean and Dalrymple, 2002).

Many inlets today have maintenance and management plans that were implemented

in order to keep the channel open for navigation as well as to counteract the erosion that

occurs at adjacent beaches. Jupiter Inlet in Florida is one such inlet that has an existing

management plan due to its history of adjacent beach erosion as well as shoaling within

the channel. In this study, the area surrounding this inlet was examined in order to

determine the historical trend of beach and shoreline erosion and to assess the

management plan for its effectiveness in regulating beach erosion.

1.2 Objective and Tasks

The objectives of this study were 1) to develop a sediment budget to analyze the

effects of the beach nourishment that has been carried out adjacent to Jupiter Inlet and 2)









to evaluate whether or not that nourishment has been successful in keeping the downdrift

beach sufficiently nourished. The tasks undertaken for this study included:

1. Data compilation of the elements relevant to the sediment (sand) budget, including
beach profiles, ebb shoal volumes, dredging volumes and nourishment volumes.

2. Determination of ebb shoal, dredging and nourishment data relevant to the
locations and time periods being analyzed.

3. Calculation of the shoreline and volume change rates at the beaches adjacent to
Jupiter Inlet.

4. Presentation of sediment budget equation specifically for Jupiter Inlet.

5. Assessment of the beach nourishment's efficacy after taking all data into
consideration in the sediment budget equation.

1.3 Outline of Chapters

Chapter 2 includes site description and a summary of the recent engineering history

of the Jupiter Inlet area as well as a summary of beach profile and sand volume data

compiled for use in the sediment budget analysis. Chapter 3 details methods used to

calculate shoreline and volume changes of the beaches updrift and downdrift of Jupiter

Inlet, describes the limitations of the profile data, and presents the shoreline and beach

volume changes that took place within selected periods of time. The derivation of the

sediment budget equation is given in Chapter 4, followed by the presentation of the

quantities used in the sediment budget and an explanation of the results of the sediment

budget. A summary of the study as well as conclusions and recommendations for further

work are included in Chapter 5.















CHAPTER 2
SITE DESCRIPTION AND DATABASE

2.1 Site Description and Recent History

2.1.1 Site Description

Jupiter Inlet is a natural waterway maintained by the Jupiter Inlet District. The

inlet connects the Loxahatchee River to the Atlantic Ocean, as shown in Figure 2-1.









Central
Embayment ,

Inlet







Figure 2-1: Jupiter Inlet connecting the Loxahatchee River forks to the Atlantic Ocean

In the present study, three separate sediment budget analyses have been conducted

for Jupiter Inlet for varying shoreline distances. Figure 2-2 displays the shoreline

surrounding the inlet and depicts the locations of the Florida Department of

Environmental Protection's (FDEP) range monuments. The first analysis encompasses an

expanse of shoreline nearly 26 km in length, with the study beginning at Monument R-75

in Martin County and continuing south to Monument R-40 in Palm Beach County. The

second analysis covers a 14.5 km distance of shoreline, beginning with Monument R-1 12









in Martin County and ending just past Monument R-36 in Palm Beach County. The final

analysis encompasses a much shorter distance of shoreline of just over 1 km, beginning at

Monument R-10 in Palm Beach County just north of Jupiter Inlet and extending south to

Monument R-15. Jupiter Inlet is located between Monuments R-12 and R-13 in northern

Palm Beach County. It is approximately 26 km south of St. Lucie Inlet and about 19 km

north of Lake Worth Inlet, as shown in Figure 2-3 (Dombrowski and Mehta, 1993).

The Jupiter Inlet system consists of jetties at the north and south banks of the inlet,

a navigational channel and an interior sand trap. The jetties and the location of the sand

trap are displayed in Figure 2-4. Originally in 1922 the north and south jetties were each

120 m long and were built of rock. In 1929 both jetties were structurally strengthened

and extended. The north jetty was extended 60 m and the south jetty 25 m. In 1956 a

sheet-piled jetty 90 m long was constructed 30 m north of the pre-existing jetty. In 1967

the south jetty was extended by 30 m (Dombrowski and Mehta, 1993). Between 1996

and 1998, the seaward end of the south jetty was lengthened by 53 m with a hook in the

southeastward direction (Mehta et al., 2005). Jupiter Inlet is approximately 112 m wide

with a mean depth of 3.9 m at the jetties. Maintained through dredging, the navigational

channel varies in width from about 206 m to 247 m and is also about 3.9 m deep (Patra,

2003). The interior sand trap located approximately 305 m westward of the inlet mouth

is intended to maintain the channel, to nourish the beach downdrift of the inlet by

placement of sand dredged from the trap, and to reduce the influx of sediment into the

Loxahatchee River (Stauble, 1993).

2.1.2 Recent History

Jupiter Inlet has existed naturally for hundreds of years. Originally, it was kept

open by the flow that passed through it from the Loxahatchee River, Jupiter Sound, and









Lake Worth Creek, closing intermittently due to natural events such as large storms

(Grella, 1993). In more recent times, from the late 1800's to the early 1900's, the inlet

closed more frequently than it had in the past due to the diversion of the natural flow

caused by Lake Worth Inlet to the south and St. Lucie Inlet to the north. The inlet was

occasionally dredged and reopened during this period, but it would again close because of

the decreased flow through it (Dombrowski and Mehta, 1993).



Palm Beach Co. -.


R 10

N RR-8



t-R-90
km R- 0


0 1

'100


.-15 P i








R-120 .-70


--2-a-- S
Marim CoB S
Palm Beach C ~


Figure 2-2: FDEP range monuments north and south of Jupiter Inlet














St. Lucie Inlet


Jupder Kilond
ndup

Jupter Sound


Martin Co. J
Poin Beach Co.
Jupit<
Conl- 18
Loke Wor
Creek





8 0 8km
We


JUPITER INLET


Lake Worth Inlet


Figure 2-3: Area map of Jupiter Inlet (Source: Buckingham, 1984, p. 3)


Figure 2-4: Photograph of Jupiter Inlet showing jetties and approximate location of sand
trap


Vo
-,


0
0-
'I'
z


>- Sand Trap
E::: =,









The Jupiter Inlet District (JID) was created in 1921 for the purpose of preserving

and maintaining the inlet and the Loxahatchee River. As mentioned, the first jetties were

built in 1922 and extended in 1929. However, the inlet closed again despite these

stabilization efforts (Grella, 1993). To keep the inlet open for navigation, periodic

dredging of a sand trap to a depth of approximately 6 m below mean water level was

implemented in 1947. Since that time the inlet has remained permanently open due to

periodic dredging and maintenance of jetties. Since then, the jetties have been modified

as mentioned, and the sand trap has been enlarged in order to reduce the entrance of

littoral sediment into the inlet and to lessen the deposition of sediment further upstream

of the trap (Mehta et al., 2005).

2.3 Beach Profile Data

Two sources of data have been used to develop the three sediment budgets. The

beach profile data used to conduct the analyses described in this report as the "FDEP

Sediment Budget" were obtained from the Bureau of Beaches and Coastal Systems of the

FDEP. Six sets of surveys consisting of beach profile data were obtained for Martin

County and Palm Beach County. Three surveys within a period of nearly 30 years were

found for each county. Ideally for this type of study the years in which the surveys were

taken for each county would coincide, but matching survey dates were not available for

Martin and Palm Beach Counties. The surveys that were found to be closest in dates

were a 1976 survey for Martin County and a 1974 survey for Palm Beach County, a 1982

survey for Martin County and a 1990 survey for Palm Beach County, and a 2002 survey

for Martin County and a 2001 survey for Palm Beach County. Table 2-1 lists the survey

dates for each county as well as the beach profile type for each survey.









Table 2-1: Beach profile data for Martin and Palm Beach Counties
County Survey Date Profile Type
1976 Wading profiles every monument;
long profiles every third monument
Martin 1982 Wading profiles every monument;
long profiles every third monument
2002 Wading and long profiles every monument
1974 Wading profiles every monument;
Palm Beach long profiles every third monument
Palm1990 Wading and long profiles every monument
2001 Wading and long profiles every monument

A wading profile consists of distance and elevation measurements of the dry beach

and includes measurements as far offshore as can be reached by wading or swimming,

which typically reaches approximately 1.5 m of water depth. A long profile is taken by a

surveying vessel and consists of the offshore distance and depth measurements that

cannot be reached by wading or swimming (Dean and Dalrymple, 2002). The long

profiles have been plotted for the three survey dates for each county in Appendix A, from

Monument R-75 in Martin County to Monument R-39 in Palm Beach County.

The sediment budget analysis presented as the "JID Sediment Budget" uses beach

profile data obtained from the Jupiter Inlet District (JID). The profile data obtained from

JID were taken by Lidberg Land Surveying of Jupiter, Florida. Nine surveys were

available for the JID sediment budget analysis. The first five were taken in May 1995,

November 1995, May 1996, November 1996 and March 1997. These include Palm

Beach County Monuments R-13 to R-17, which are south of Jupiter Inlet. The next three

were taken in August 2001, June 2002 and October 2002 and include Monuments R-10

through R-21 in Palm Beach County. The last survey was taken in April 2004 and

includes Monuments R-13 through R-17 in Palm Beach County, south of the inlet. The

beach profiles based on the JID profile data have been plotted in Appendix B.









2.4 Ebb Shoal Volume Data

Availability of Jupiter Inlet's ebb shoal volume measurements was limited. One

record (Dombrowski, 1994) found contained eleven volume estimates taken in various

years from 1883 to 1993. These volume measurements of the ebb shoal are presented in

Table 2-2.

Table 2-2: Jupiter Inlet ebb shoal volumes (Source: Dombrowski, 1994)
Year Volume
Year (in3)
(m )
1883 690,000
1947 0 (inlet closed)
1957 380,000
1967 760,000
1978 310,000
1979 680,000
1980 310,000
1981 230,000
1986 690,000
1993 740,000
1993 1,530,000

A second source of ebb shoal volume data was found on the Palm Beach County

Department of Environmental Resources Management website. This source contained

survey data taken of the Jupiter Inlet ebb tidal shoal for the years 2000 and 2001. Based

on these surveys, volume changes were estimated between the two years.

2.5 Dredging Data

Jupiter Inlet has an extensive history of dredging. Even in the early 1900's the inlet

was dredged simply to keep it open. As mentioned, since then, periodic dredging has

been implemented with the creation of the sand trap. For the time period covered in the

sediment budget analyses, the material dredged from the inlet channel and the trap has

been placed on the beach downdrift of Jupiter Inlet as nourishment. Volumes dredged

from the channel and the trap between 1974 and 2004 are presented in Table 2-3. The









data were obtained from Michael Grella of JID (personal communication, March 20,

2006). The dredged sediment volumes between 1974 and 2001 within the limits of the

sediment budget for Palm Beach County for the FDEP budget have an annual average

value of approximately 34,800 m3 over that total period. The dredged volumes in 2001

and 2002 within the limits of the sediment budget using the JID beach profiles have an

annual average of about 48,500 m3.

Table 2-3: Jupiter Inlet and interior sand trap dredging volumes
Year Dredged Volume
(m3)
1975 75,003
1977 68,733
1979 71,104
1981 57,342
1983 45,873
1985 58,106
1986 50,078
1988 52,984
1990 64,987
1991 43,466
1993 47,030
1994 54,681
1995 55,048
1996 24,114
1998 64,987
2000 42,968
2001 63,382
2002 33,640
2004 43,580

2.6 Beach Nourishment Data

2.6.1 Downdrift Beach Nourishment Volumes

Records of downdrift nourishment events are shown in Table 2-4. The data were

obtained from Michael Grella of JID (personal communication, March 20, 2006), from

the Beach Erosion Control Project Monitoring Database Information System maintained

by the Beaches & Shores Resource Center of the Florida State University, Tallahassee









and from a report prepared by Taylor Engineering for Palm Beach County (Albada and

Craig, 2006). The volumes of sediment dredged from the inlet channel and the sand trap,

as shown previously in Table 2-3, are taken to be equal to the volumes of sediment

placed on the beach from the dredging, and therefore are included in the total

nourishment volumes shown in Table 2-4.

The Jupiter Inlet Management Plan, approved by JID in 1992, adopted 46,000 m3

as the minimum sand volume to be placed on the downdrift beach annually (Grella,

1993). Prior to that plan, a section of the beach about 244 m in length just south of the

jetty was used for the placement of nourishment. In order to increase the retention time

of the same volume of sand, this length of beach was doubled to approximately 488 m as

shown in Figure 2-5 (Mehta et al., 2005).

The two key sources of sediment used for beach nourishment downdrift of Jupiter

Inlet are the sand trap and the Intracoastal Waterway, as shown in Figure 2-6. The sand

stored in the sand trap is dredged nearly every year. Also, excess sand is dredged from

the Intracoastal Waterway by the U. S. Army Corps of Engineers as well as the Florida

Inland Navigation District (FIND), and a portion of the dredged sediment is placed on the

downdrift beach. The recommended plan for the nourishment of the beach is that the

dredging of the sand trap be completed before the end of April each year and placed on

the beach. If this volume is insufficient at that time, then dredging should be conducted

in November instead. It has also been recommended that the Intracoastal Waterway be

dredged and the sediment placed on the downdrift beach in April if the sand trap has been

dredged in November, or in November if the sand trap has been dredged in April (Grella,

1993).










Table 2-4: Jupiter Inlet downdrift beach nourishment volumes
Year Time of Year of Total Approximate Source(s) of
Nourishment Nourishment Placement of Sediment
(If Available) Volume Nourishment
(m3)
1975 192,744 Monument R-13 to R-14 Inlet/Sand Trap,
Intracoastal
Waterway
1977 68,733 Monument R-13 to R-14 Inlet/Sand Trap
1979 161,933 Monument R-13 to R-14 Inlet/Sand Trap,
Intracoastal
Waterway
1981 57,342 Monument R-13 to R-14 Inlet/Sand Trap
1983 45,873 Monument R-13 to R-14 Inlet/Sand Trap
1985 58,106 Monument R-13 to R-14 Inlet/Sand Trap
1986 50,078 Monument R-13 to R-14 Inlet/Sand Trap
1988 132,115 Monument R-13 to R-14 Inlet/Sand Trap,
Intracoastal
Waterway
1989 8,792 Monument R-13 to R-14 Intracoastal
Waterway
1990 64,987 Monument R-13 to R-14 Inlet/Sand Trap
1991 43,466 Monument R-13 to R-14 Inlet/Sand Trap
1992 106,273 Monument R-13 to R-15 Intracoastal
Waterway
1993 47,030 Monument R-13 to R-15 Inlet/Sand Trap
1994 54,681 Monument R-13 to R-15 Inlet/Sand Trap
1995 November 1995 139,530 Monument R-13 to R-15 Inlet/Sand Trap,
to February 1996 Intracoastal
Waterway
1995 Spring 461,635 Monument R-18 to R-19 Ebb Tidal Delta
(Carlin Park)
1996 24,114 Monument R-13 to R-15 Inlet/Sand Trap
1998 64,987 Monument R-13 to R-15 Inlet/Sand Trap
2000 Contract Award 70,171 Monument R-13 to R-15 Inlet/Sand Trap,
February 2000 Intracoastal
Waterway
2001 Contract Award 112,948 Monument R-13 to R-15 Inlet/Sand Trap,
February 2001 Intracoastal
Waterway
2002 Contract Award 33,640 Monument R-13 to R-15 Inlet/Sand Trap
February 2002
2002 December 2001 477,844 Monument R-18 to R-19 Borrow Area Approx.
to March 2002 (Carlin Park) 3.2 km NE of Jupiter
Inlet
2004 January 2004 to 127,681 Monument R-13 to R-15 Inlet/Sand Trap,
March 2004 Intracoastal
Waterway











































Figure 2-5: Jupiter Inlet Management Plan recommended increase in nourishment beach
length (Source: Grella, 1993, p. 247)


'V.
A^
C-
Vr
1-
-A^
C'*%


0 =o 200m
SCole
rL
l-~_ Deposition Basins
CjintC


.B3Miomfm'Us Erosion
:J." ::'"""." Accretion


Figure 2-6: Sand trap and Intracoastal Waterway deposition basin from which sediment
is dredged to be used as nourishment (Source: Buckingham, 1984, p. 7)









2.6.2 Updrift Beach Nourishment Volumes

Some nourishment events have also occurred on the beach updrift of Jupiter Inlet

for the time period under consideration for the FDEP sediment budget analyses. The

volumes that were placed on the updrift beach are presented in Table 2-5.

Based on Aubrey and Dekimpe, 1988, all except two of the updrift nourishment

events that occurred through 1987 were placed within the bounds of Monument R-75 and

Monument R-1 11 of Martin County. The first 1983 nourishment as well as the 1986

nourishment are known to have been placed just north of Jupiter Inlet in Palm Beach

County, but the exact locations are uncertain. From the records obtained from the

Beaches & Shores Resource Center, the 1995/1996 nourishment is known to have been

placed between Monuments R-77 and R-106 of Martin County. A renourishment project

was scheduled for 2001 for Jupiter Island updrift of the inlet, but no indication that the

placement had occurred could be found (Tabar et al., 2002).

Table 2-5: Jupiter Inlet updrift beach nourishment volumes
Year Nourishment Volume Source of Data
(m3)
1974 741,618 Aubrey and Dekimpe, 1988
1977 366,986 Aubrey and Dekimpe, 1988
1978 649,872 Aubrey and Dekimpe, 1988
1983 108,414 Michael Grella (personal communication,
March 20, 2006)
1983 764,555 Aubrey and Dekimpe, 1988
1986 116,916 Michael Grella (personal communication,
March 20, 2006)
1987 1,704,957 Aubrey and Dekimpe, 1988
1995/1996 1,330,325 Beaches & Shores Resource Center














CHAPTER 3
SHORELINE AND BEACH VOLUME CHANGES

3.1 Shoreline and Beach Volume Change Calculation Methods

Two main components that form the basis for the sediment budget for Jupiter Inlet

are the updrift and downdrift beach volume change rates. In order to determine these

rates, two computer programs that were developed by Dr. Robert Dean (personal

communication, June, 2005) for use in an earlier development of a sediment budget for

Sebastian Inlet, also located along the east coast of Florida (Dean, 2005), were modified

and used. The first program inputs beach profile survey data. These surveys were

obtained from the FDEP's Bureau of Beaches and Coastal Systems database and from

records provided by the Jupiter Inlet District. The program organizes the input data for

plotting profiles at each survey monument and calculates shoreline position changes and

the unit volume (i.e., volume of sediment per unit beach width) changes for the

determined time period based on these survey data. For each monument that has a long

survey profile, the profile area between the water level (NGVD) and the sand surface

from a selected (base line) position on land to the depth of closure is estimated by the

trapezoidal rule. The change in area from one survey date to the next is then calculated in

order to find accretion or erosion that has occurred at the monument in that period. This

area change is then represented as the corresponding unit volume change for use in the

second program.

The second program analyzes the shoreline position and unit volume change

calculations that are output from the first program, and determines the average shoreline









and volumetric changes per year. In order to determine the volumetric change per year,

the unit volume change from an earlier survey date is subtracted from the unit volume

change from a subsequent survey date. The unit volume change is then divided by the

number of years in between the survey dates to obtain the unit volume change rate. In

order to obtain the volume change rates for the intersurvey periods analyzed, the end-area

method is used, which averages the unit volume change rates at each monument, and

multiplies this rate by the distance between each monument. The second program also

allows for the calculation of the volume change rate at user-specified points that need to

be examined closely, for example, at the north and south boundaries of the inlet. From

these two programs, the total volumetric rates of gain or loss of sediment are determined

for the beaches updrift and downdrift of the inlet. These values are then used in the

determination of the sediment budget, as described in Chapter 4.

3.2 Data Limitations and Uncertainties

There are several uncertainties to be aware of when using beach profile survey data

to calculate volumetric changes. As mentioned in Chapter 2, beach profile measurements

are taken using two surveying processes, the first being the wading survey, and the

second being the boat survey. The wading portion of the survey is conducted by a survey

crew which uses "standard land surveying equipment" to determine the elevations of the

dry beach, and as far offshore as is possible to reach by wading or swimming, typically

up to about 1.5 m of water depth. Usually, a surveying vessel is used to obtain the

offshore portion of the survey. This vessel commonly has a fathometer and a coordinate

positioning system onboard so that the vessel's position can be correlated with depth

measurements (Dean and Dalrymple, 2002). Early surveys, however, did not have the

same level of technology that is used now, especially for the offshore portion of the









survey. Generally, vessels had to stay on the profile line visually by using the range

poles, so errors were more prevalent in the offshore depth measurements.

3.2.1 Data Uncertainties

Occasionally, there are discrepancies other than measurement errors in the beach

profile survey data. For example, in the survey made in 1976 in Martin County,

monument coordinates were missing for Monument R-84. It was documented in the

FDEP database that the monument had been relocated after the 1976 survey and before

the 1982 survey, so using the coordinates of Monument R-84 from the most recent

survey, which is a common way to correct such a data omission, would have been

inaccurate. Therefore, aerial photographs taken in 1972 and checked in 1975 for

accuracy were inspected, and distances were scaled from Monuments R-83 to R-84 and

from R-84 to R-85. Based on these distances, and on the coordinates of Monuments R-

83 and R-85 documented in the 1976 survey, coordinates for Monument R-84 were

obtained by interpolation. This seemed the most reliable method because of the

proximity in time between the aerials and the survey, and also because it took into

account an estimate of the distance between the monuments, rather than assuming that the

monuments were evenly spaced.

An additional uncertainty occurred in the 1982 survey at Monument R-105 of

Martin County. As mentioned, the early surveys only had long profiles recorded for

every third monument; therefore R-105 should have had long profile measurements for

each survey date. However, in 1982 the measurements were only taken to an offshore

distance of about 45.7 m, with a corresponding maximum depth of -1.6 m. Because the

depth of closure (which is the offshore limit of a volume calculation) was not reached in

the measurements, a unit volume change could not be calculated at this location. Thus,









for the periods from 1976 to 1982 and from 1982 to 2002 in Martin County, the beach

volume change rates had to be estimated based on unit volume changes at Monuments R-

102 and R-108 and averaged over the distance between these two monuments, which is a

longer distance than the usual every third monument distance that was normally used for

the other early survey calculations.

3.2.2 Corrections for Non-Closure of Profiles

The depth of closure is a depth at which all beach profiles from any given time

normally converge (and do not diverge significantly again beyond this depth), as

exemplified in Figure 3-1 (Dean and Dalrymple, 2002). For the calculations made in the

previously mentioned programs, the seaward distance corresponding to the depth of

closure from the shoreline was used as a limit for the volume calculations. It can be seen

from the beach profiles shown in Appendices A and B that there is non-closure of many

of the profiles. These data suggest that there was probably some error in the 1976 and

1982 surveys from Martin County, and the 1974 survey from Palm Beach County.









........ al
depth of
Closure







Figure 3-1: Schematic diagram defining depth of closure, where all offshore profiles
converge to a certain depth









Because of the lack of obvious closure depth in the Martin County profiles, and

questionable closure depth in the Palm Beach County profiles, a method other than visual

inspection had to be used to determine a mean closure depth for each county. The

standard deviation of the depths at every monument was calculated separately at the

shoreline and at every 25 m distance offshore for each county. The depth of closure was

chosen at the point where the standard deviation was the least. These closure depths were

-3.66 m at a 350 m distance from the shoreline in Martin County, and -3.11 m at a 250 m

distance from the shoreline in Palm Beach County. As described later, sediment volume

analysis was extended by examining the effect of changing (increasing and decreasing)

the depth of closure. This was done in order to make a quantitative assessment of the

error introduced by selecting a particular depth of closure.

3.2.3 Corrections for Monument Relocation

After the 1976 survey for Martin County and the 1974 survey for Palm Beach

County, some of the monuments were relocated by FDEP, including Monument R-84 of

Martin County as mentioned earlier. The first of the two programs used for the beach

volume calculations accounts for monument relocation. It compares the monument

coordinates from survey to survey, and if the coordinates differ, it calculates the distance

between the monument's old location and its new location. If this distance exceeds 0.031

m, then an appropriate shift is calculated and added algebraically to every distance

measured along the profile of the original monument.

3.3 FDEP Intersurvey Interval: 1974-1986

For the FDEP intersurvey interval of 1974 to 1986, shoreline change data were

available for every monument. However, unit volume change rates for this interval could

only be calculated for every third monument because in the earlier surveys, including the









1976 and 1982 surveys for Martin County and the 1974 survey for Palm Beach County,

long beach profiles were taken for only the first monument of a county and for every

third monument thereafter. Therefore, the unit volume change rates could only be found

for the long beach profiles, in which depths and distances were recorded up to the depth

of closure.

3.3.1 Shoreline Changes

Figure 3-2 displays the shoreline change rates for each monument for the period

between the 1976 and 1982 FDEP surveys in Martin County, and between the 1974 and

1990 FDEP surveys in Palm Beach County. The largest rate of accretion of the shoreline

updrift of Jupiter Inlet based on these data is almost 6.25 m per year at Monument R-84

in Martin County, and the largest rate of erosion of the updrift shoreline is nearly 4 m per

year at R-105 in Martin County. The shoreline change rates on the updrift side of the

inlet show accretion as well as erosion, with no obvious mean trend. Downdrift of

Jupiter Inlet, the highest rate of shoreline accretion observed is around 2.4 m per year at

Monuments R-25 and R-26 in Palm Beach County, and the highest rate of shoreline

erosion is just over 2 m per year at R-29 in Palm Beach County. The shoreline change

downdrift of the inlet for this time period tends to show trends of accretion with smaller

amounts of erosion interspersed.

3.3.2 Sediment Volume Changes

The unit volume change rates for each monument for the period between the 1976

and 1982 FDEP surveys in Martin County and for the 1974 and 1990 FDEP surveys in

Palm Beach County are shown in Figure 3-3. The largest volumetric rate of accretion

occurring updrift of Jupiter Inlet is about 22 m3/m per year at Monument R-84 in Martin

County, and the largest volumetric rate of erosion updrift of the inlet is nearly 30 m3/m









per year at R-93 in Martin County. The unit volume change rates on the updrift side of

the inlet show sections of the beach having high accretion as well as high erosion, where

neither accretion nor erosion dominates. Downdrift of the inlet, the highest volumetric

rate of accretion is almost 12 m3/m per year at Monument R-27, and the highest

volumetric rate of erosion is just over 9 m3/m per year at R-36. The unit volume change

rates downdrift of the inlet for this period show a small degree of erosion just past the

inlet, with high accretion just past the erosional stretch. Further downdrift, accretion and

erosion occur without a noticeable trend.

3.4 FDEP Intersurvey Interval: 1986-2002

For the FDEP intersurvey interval of 1986 to 2002, shoreline change data were

available for every monument. For Martin County, unit volume change rates for this

interval could be calculated for only every third monument. Although the second survey

of the interval is from 2002 and contains long beach profile data for every monument, the

first survey of the interval is from 1982, which has long beach profiles for only every

third monument. Therefore, the unit volume change could only be calculated for those

monuments which had long beach profile survey data for both years. For Palm Beach

County, the unit volume changes for this interval were calculated for every monument

because the surveys were from 1990 and 2001, each of which had long beach profile

surveys for every monument.

3.4.1 Shoreline Changes

Figure 3-4 displays the shoreline change rates for each monument for the period

between the 1982 and 2002 FDEP beach profile surveys in Martin County, and between

the 1990 and 2001 FDEP surveys in Palm Beach County. Updrift of Jupiter Inlet, the

highest rate of shoreline accretion is around 3 m per year at Monument R-10 in Palm









Beach County, with R-106, R-118, and R-120 having similarly high rates of accretion.

The rate of shoreline erosion is comparatively small and does not even reach 0.5 m per

year at any point. For this period, the shoreline change rate updrift of the inlet tends to be

accretive. On the shoreline downdrift of Jupiter Inlet, the highest rate of accretion is

around 5 m per year at Monument R-36 and nearly the same at R-31 in Palm Beach

County. The highest rate of erosion is around 2.75 m per year at Monuments R-14 and

R-23 in Palm Beach County. Erosion and accretion both occur up to about Monument R-

26, and past this point high accretion occurs.

3.4.2 Sediment Volume Changes

The unit volume change rates for each monument for the period between the 1982

and 2002 FDEP beach profile surveys in Martin County and for 1990 and 2001 in Palm

Beach County are displayed in Figure 3-5. Updrift of Jupiter Inlet, the highest rate of

volumetric accretion is about 20 m3/m per year at Monument R-10 in Palm Beach

County, with the next highest rate at R-120 in Martin County. These two locations

displaying high volumetric accretion rates coincide with two of the locations showing

high shoreline accretion rates. The largest rate of volumetric erosion updrift of the

shoreline occurs at Monument R-12 of Palm Beach County, with a value of about 21.75

m3/m per year. All other volumetric rates of erosion updrift of the inlet are below 8.5

m3/m per year, and few locations display erosion. For this period, similar to the shoreline

change rates updrift of the inlet, the unit volume change rates tend to be accretive.

Downdrift of the inlet, the highest volumetric rate of accretion is nearly 39 m3/m per year

at Monument R-30 in Palm Beach County. The highest volumetric rate of erosion is

nearly 20 m3/m per year at R-13 in Palm Beach County. The unit volume change rate









downdrift of the inlet shows drastic erosion immediately downdrift, and then it is mainly

accretive for the rest of the beach length analyzed.

3.5 FDEP Intersurvey Combined Interval: 1974-2002

For the FDEP intersurvey combined interval of 1974 to 2002, the shoreline change

rates were calculated at every monument. However, the unit volume change rates could

be calculated only for every third monument. For Martin County, the first survey for this

interval is from 1976 and contains long beach profile survey data for every third

monument, while the second survey is from 2002 and contains long beach profiles for

every monument. For Palm Beach County, the first survey is from 1974 and contains

long beach profiles for the first monument and every third monument thereafter, and the

second survey is from 2001 and contains long beach profiles for every monument.

Therefore, for both counties, unit volume change rates could be determined only for

every third monument.

3.5.1 Shoreline Changes

Figure 3-6 shows the shoreline change rates for the total time period analyzed, from

1976 to 2002 in Martin County and 1974 to 2001 in Palm Beach County. The shoreline

change rates updrift and downdrift of Jupiter Inlet mainly show trends of accretion for

this time interval. Immediately updrift and downdrift of the inlet, there is more variation,

with erosion at Monuments R-12 and R-13 in Palm Beach County, but overall the

shoreline is seen to have accreted. The highest rate of accretion updrift of the inlet is just

over 2 m per year in Martin County, and the highest rate of erosion updrift is about 1.25

m per year in Palm Beach County at Monument R-12. On the shoreline downdrift of the

inlet, the highest rate of accretion is around 2.5 m per year at Monument R-31, and the

highest rate of erosion is almost 1.4 m per year. Downdrift of the inlet, erosion only










occurs over two small stretches of the shoreline, with the rest of the shoreline showing

accretion.

3.5.2 Sediment Volume Changes

The unit volume change rates from 1976 to 2002 in Martin County and from 1974

to 2001 in Palm Beach County are shown in Figure 3-7. Updrift of Jupiter Inlet, there are

large stretches of volumetric accretion with one notable stretch of erosion from about

Monument R-90 to R-105. The largest unit volume change rate showing erosion updrift

of the inlet occurs at Monument R-12 in Palm Beach County and is nearly 14 m3/m per

year. Downdrift of the inlet, there is a small amount of volumetric erosion adjacent to the

inlet, at Monument R-15. Consistent with the trends that were displayed by the shoreline

change rates for this period, the unit volume change rates also display mainly trends of

accretion.


Shoreline Change per Monument in Martin County (1976-1982) and Palm Beach County (1974-1990)
8 --- -
---- ------- ----Martin County Palm Beach County ----------
6 .. .
Accretion
Si
E





a) -2

Ji
,, -4 -


R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments

Figure 3-2: Shoreline change rates for the period from 1976 to 1982 in Martin County
and from 1974 to 1990 in Palm Beach County











Unit Volume Change per Monument in Martin County (1976-1982) and Palm Beach County (1974-1990)
A4_0


I 20
E
C
0
S10
0)
cE

E -iC
0
= -2C


R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments

Figure 3-3: Unit volume change rates for the period from 1976 to 1982 in Martin County
and from 1974 to 1990 in Palm Beach County


Shoreline Change per Monument in Martin County (1982-2002) and Palm Beach County (1990-2001)
8 1--


4
E
0






) -4
a)
0
Cd -4


R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments

Figure 3-4: Shoreline change rates for the period from 1982 to 2002 in Martin County
and from 1990 to 2001 in Palm Beach County


--------------------Martin County Palm Beach County-----------

Accretion





A AAA


--------------------Martin County


Accretion




(~\AIF.


I


40


Palm Beach County----------.













Unit Volume Change per Monument in Martin County (1982-2002) and Palm Beach County (1990-2001)
40 ,, I- I I I i
----- ---------- ----Martin County Palm Beach County--- ---

30 -
Accretion

20 -


20 -...|.... ... ... ... .. ... ..... ... .. ....






-10


-20 -

Erosion
-30 ..... ..... Jupiter Inlet.



R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments


-5: Unit volume change rates for the period from 1982 to 2002 in Martin County
and from 1990 to 2001 in Palm Beach County


Shoreline Change per Monument in Martin County (1976-2002) and Palm Beach County (1974-2001)
8 i i !i I


6


i4
E
0
2
CL
0

- 2

0


U) o
a-
0
r -


-Sik ..


R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments


Figure 3-6: Shoreline change rates for the combined period from 1976 to 2002 in Martin
County and from 1974 to 2001 in Palm Beach County


dI)
0)

C
0

E



4)
0)

0

E
Ds


Figure 3


<---------------------- Martin County
Ae

Accretion
-!


Jupiter Inlet


Erosion
. . . . . .. .


Palm Beach County ------ 4


i I i i











Unit Volume Change per Monument in Martin County (1976-2002) and Palm Beach County (1974-2001)
40 ,, I- I I I i
<---------------------Martin County i Palm Beach County-----------
30 ... :
Accretion
| 20. .. ..
E
"=










Erosion : : I :
0



-2 0 ........ .... .. . . . . ... J i I. ne. .. ....
")





.0 ---------- ----- ------ ---i--- --i-------
Erosion
I-30

-40 I I I
R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments

Figure 3-7: Unit volume change rates for the combined period from 1976 to 2002 in
Martin County and from 1974 to 2001 in Palm Beach County

3.6 Volume Change Sensitivity to Depth of Closure

As mentioned, because the depths of closure were not obvious from the plots of the

beach profiles, the standard deviation method was used to find the mean depth of closure

for each county. Thus it was necessary to check for any significant sources of error

introduced by assuming these values of the depth of closure.

Depths of closure of -3 m and -4 m were used for computing sediment volumes to

compare with those determined using the standard deviation-derived depths of closure.

These two depths were chosen because they bracket the -3.66 m used for Martin County

and the -3.11 m used for Palm Beach County. The -3 m depth represents an 18 %

decrease from the original -3.66 m for Martin County and only a 3.5 % decrease from the

-3.11 m for Palm Beach County. The -4 m depth introduces only a 9.3 % increase for

Martin County and a 28 % increase for Palm Beach County.









For all time periods considered, specifically 1976 to 1982, 1982 to 2002 and 1976

to 2002 for Martin County and 1974 to 1990, 1990 to 2001 and 1974 to 2001 for Palm

Beach County, the unit volume change rate differences between the -3 m depth of closure

volumes and the standard deviation-derived depth of closure volumes were considerably

larger in Martin County than in Palm Beach County. This can be attributed to the fact

that the standard deviation-derived depth of closure of -3.11 m for Palm Beach County is

closer to -3 m than the standard deviation depth of -3.66 m for Martin County. For the

first and last time periods considered, which are 1976 to 1982 and 1976 to 2002 for

Martin County and 1974 to 1990 and 1974 to 2001 for Palm Beach County, the unit

volume change rate differences between the -4 m depth of closure volumes and the

standard deviation depth of closure volumes were larger in Palm Beach County than in

Martin County. This is because the standard deviation depth for Martin County is closer

to -4 m than for Palm Beach County. Although the unit volume change rates do differ for

each county when the depths of closure are varied, these differences are minor. This can

be seen in Figures 3-8, 3-9, and 3-10.

3.6.1 Volume Change Sensitivity to Depth of Closure: 1974 to 1986

For the first period, from 1976 to 1982 in Martin County and from 1974 to 1990 in

Palm Beach County, the unit volume change rates corresponding to all depths of closure

are displayed in Figure 3-8. On average, the unit volume change rate differences found

by subtracting the standard deviation depth volumes from the -3 m depth volumes were

approximately 1 m3/m per year and -0.56 m3/m per year, respectively. This means that

within the first period of time considered, the unit volume change rate corresponding to

-3 m is greater than the rate for -3.66 m in Martin County, and the rate for -3 m is less

than the rate for -3.11 m in Palm Beach County. For the same time period, the rate










differences between -4 m depth volumes and the standard deviation depth volumes were

on average about -0.68 m3/m per year and 1.68 m3/m per year for Martin County and

Palm Beach County, respectively. Therefore, the unit volume change rate corresponding

to -4 m is less than the rate for -3.66 m in Martin County and greater than the rate for

-3.11 m in Palm Beach County.


Unit Volume Change per Monument in Martin County (1976-1982) and Palm Beach County (1974-1990)
4 0 i
S--Standard Deviation Depth Volumes
30 ----3 m Depth Volumes
-4 m Depth Volumes I
I Accretion
S20 -
o
| 10




E -10 -
> iJupiter Inlet
-20
Erosion
-30 -
-------------------- Martin County Palm Beach County ------- --+
-40 ii I I I I i
R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments

Figure 3-8: Unit volume change rates using varying depths of closure for the period from
1976 to 1982 in Martin County and from 1974 to 1990 in Palm Beach County

3.6.2 Volume Change Sensitivity to Depth of Closure: 1986 to 2002

For the second period from 1982 to 2002 in Martin County and from 1990 to 2001

in Palm Beach County, the unit volume change rates for all depths of closure are shown

in Figure 3-9. The unit volume change rate differences found by subtracting the standard

deviation depth volumes from the -3 m depth volumes were on average about 1.3 m3/m

per year and 0.2 m3/m per year, respectively. This means that the rate corresponding to

-3 m is greater than the rate for -3.66 m in Martin County and is also greater than the rate










for -3.11 m in Palm Beach County. The rate differences between -4 m depth volumes

and the standard deviation depth volumes were about -0.35 m3/m per year on average for

Martin County and -0.22 m3/m per year on average for Palm Beach County. This means

that rates corresponding to -4 m are less than the rates corresponding to -3.66 m in Martin

County and -3.11 m in Palm Beach County.


Unit Volume Change per Monument in Martin County (1982-2002) and Palm Beach County (1990-2001)
40 I
-Standard Deviation Depth Volumes I
30 -3 m Depth Volumes

2E -4 m Depth Volumes
v 20 ". .. : .. p .

E Accretion




-10 -
SI :I
0. 0i -- I .

E Erosion A; \


-30 : Jupiter Inlet
.-.---------.----------Martin County Palm Beach County--- -------.
-40 i i i i- -
R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments

Figure 3-9: Unit volume change rates using varying depths of closure for the period from
1982 to 2002 in Martin County and from 1990 to 2001 in Palm Beach County

3.6.3 Volume Change Sensitivity to Depth of Closure: 1974 to 2002

The unit volume change rates for all depths of closure for the combined period

from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm Beach County are

displayed in Figure 3-10. The average unit volume change rate differences found by

subtracting the standard deviation depth volumes from the -3m depth volumes were

around 1.37 m3/m per year and -0.33 m3/m per year for Martin County and Palm Beach

County, respectively. This means that the rate corresponding to -3 m is greater than the










rate for -3.66 m in Martin County, and that the rate for -3 m is less than the rate for -3.11

m in Palm Beach County. The unit volume change rate differences between -4 m depth

volumes and the standard deviation depth volumes were on average about -0.48 m3/m per

year for Martin County and 0.60 m3/m per year for Palm Beach County. Therefore, the

unit volume change rates corresponding to -4 m are less than the rates for -3.66 m in

Martin County and more than the rates for -3.11 m in Palm Beach County.


Unit Volume Change per Monument in Martin County (1976-2002) and Palm Beach County (1974-2001)
40 ,-- I --- -
-Standard Deviation Depth Volumes I
30 -3 m Depth Volumes
-4 m Depth Volumes
3 20 .. ..
E
o Accretion
(D 10 I .



0) I

> : Erosion i Jupiter Inlet
= -20 . .. . . !


-30 I
-----------------------Martin County Palm Beach County-----------.
a 40 ;------------------- i----- -----i-------------




-4 0 I I I i I I
R-84 R-94 R-104 R-114 R-124 R-7 R-17 R-27 R-37
Monuments

Figure 3-10: Unit volume change rates using varying depths of closure for the combined
period from 1976 to 2002 in Martin County and from 1974 to 2001 in Palm
Beach County

3.7 JID Intersurvey Interval: 1995-1996

For the JID intersurvey interval of May 1995 to May 1996, both the shoreline and

the unit volume change rates were calculated just south of Jupiter Inlet for Monuments R-

13 to R-17.









3.7.1 Shoreline Changes

The shoreline change rates at each monument are displayed in Figure 3-11 for the

period between the 1995 and 1996 JID surveys in Palm Beach County. The highest

accretion rate seen on this downdrift shoreline is about 9.4 m per year at Monument R-

13. The shoreline continues to show trends of accretion until about R-15, where it begins

to be erosive. This continues to R-17 where the highest rate of erosion of 21.3 m per year

is seen.

3.7.2 Sediment Volume Changes

Figure 3-12 displays the unit volume change rates for each monument for the

period between the 1995 and 1996 JID surveys in Palm Beach County. The shoreline is

seen to accrete from Monument R-13 to R-15. The highest rate of volumetric accretion is

just over 81 m3/m per year occurring at Monument R-13. Past Monument R-15, the

shoreline is erosive, with the highest rate being 178 m3/m per year at Monument R-17.

3.8 JID Intersurvey Interval: 1996-1997

For the JID intersurvey interval of May 1996 to March 1997, both the shoreline and

the unit volume change rates were calculated for Monuments R-13 to R-17, just south of

Jupiter Inlet.

3.8.1 Shoreline Changes

Figure 3-13 displays the shoreline change rates at each monument for the period

between the 1996 and 1997 surveys in Palm Beach County. The highest rate of accretion

is seen to be just over 42 m per year at Monument R-13, just downdrift of the inlet. The

highest rate of erosion is 28.5 m per year at Monument R-15. This stretch of shoreline is

accretive directly downdrift of the inlet, starts to erode near Monument R-15, and then

begins accreting again after Monument R-16.









3.8.2 Sediment Volume Changes

The unit volume change rates for each monument for the period between 1996 and

1997 in Palm Beach County are displayed in Figure 3-14. The largest rate of volumetric

accretion occurs at Monument R-13, with a value of 152.3 m3/m per year. The highest

rate of volumetric erosion is 238.3 m3/m per year at Monument R-15. This stretch of

shoreline displays mostly erosion, with accretion occurring only at Monuments R-13 and

R-16.

3.9 JID Intersurvey Combined Interval: 1995-2004

For the JID intersurvey combined interval of May 1995 to April 2004, both the

shoreline and the unit volume change rates were calculated just south of Jupiter Inlet for

Monuments R-13 to R-17.

3.9.1 Shoreline Changes

Figure 3-15 displays the shoreline change rates at each monument for the period

between the 1995 and 2004 JID surveys in Palm Beach County. The only location where

accretion occurs is at Monument R-13 where the rate is about 1.3 m per year. Over the

rest of the length of shoreline there is a slightly erosive trend. The highest rate of erosion

is 5.3 m per year and occurs at Monument R-15.

3.9.2 Sediment Volume Changes

The unit volume change rates from 1995 to 2004 in Palm Beach County are shown

in Figure 3-16. Monument R-13 is the only location showing accretion, with a rate of

about 19 m3/m per year. The rest of the shoreline from Monument R-14 to R-17 shows

erosive trends. The largest rate of volumetric erosion is just over 32 m3/m per year at

Monument R- 15.









3.10 JID Intersurvey Interval: 2001-2002

Shoreline and unit volume change rates for the JID intersurvey interval of August

2001 to October 2002 were calculated separately from the 1995, 1996, 1997 and 2004

JID data. This is because the 2001 and 2002 surveys included data for Monuments R-10

through R-21 whereas the other surveys included data only for Monuments R-13 to R-17,

south of Jupiter Inlet. For the JID intersurvey interval of August 2001 to October 2002,

both the shoreline and the unit volume change rates were calculated at every monument.

3.10.1 Shoreline Changes

Figure 3-17 displays the shoreline change rates at each monument for the period

between the 2001 and 2002 JID surveys in Palm Beach County. There are only profiles

for three monuments on the updrift side of the inlet, at which the highest rate of accretion

is approximately 3.4 m per year at Monument R-10 and the highest rate of erosion is

nearly 3.75 m per year at R-12. On the shoreline downdrift of the inlet, the highest rate

of accretion is seen to be just over 40 m per year at R-18, whereas the highest rate of

erosion, which is also the only erosion seen over the analyzed distance, is only around 7

m per year at R-20. The downdrift shoreline displays a mainly accretive trend between

2001 and 2002.

3.10.2 Sediment Volume Changes

The unit volume change rates for each monument for the period between the 2001

and 2002 JID beach profile surveys in Palm Beach County are displayed in Figure 3-18.

Updrift of Jupiter Inlet, the highest rate of volumetric accretion is almost 11 m3/m per

year at Monument R-10. The largest rate of volumetric erosion updrift of the inlet occurs

at Monument R-12, with a value of just over 25 m3/m per year. Downdrift of the inlet,

the highest volumetric rate of accretion is nearly 200 m3/m per year at Monument R-18.












Erosion on the downdrift side of the inlet is seen at only one monument, R-20, and is


only approximately 3.75 m3/m per year. The unit volume change rate downdrift of the


inlet shows accretion immediately downdrift, and the trend is mainly largely accretive for


the rest of the analyzed beach length as well, with only one monument showing low rates


of erosion.


Shoreline Change per Monument in Palm Beach County between May 1995 and May 1996


W1-13 R-14 R-15 R-16 R-17
Monuments
Figure 3-11: Shoreline change rates for the period from 1995 to 1996 just south of
Jupiter Inlet in Palm Beach County

Unit Volume Change per Monument in Palm Beach County between May 1995 and May 1996
250 ,

200-
Accretion
150
E
| 100-

50
CL
SE0 ------- ------------------

E -50

> -100
= Jupiter Inlet
-150-
Erosion
-200-

-2 -13 R-'14 R-15 R-16 R-17
Monuments
Figure 3-12: Unit volume change rates for the period from 1995 to 1996 just south of
Jupiter Inlet in Palm Beach County


Accretion











Jupiter Inlet Erosion














Shoreline Change per Monument in Palm Beach County between May 1996 and March 1997


E


CL


Cn
0



(9

-
0



4)
O
t--
0)
-c
Cd5


R-15
Monuments


R-17


Figure 3-13: Shoreline change rates for the period from 1996 to 1997 just south of

Jupiter Inlet in Palm Beach County



Unit Volume Change per Monument in Palm Beach County between May 1996 and March 1997


ci
E
C
0


0)




a
Q.






.E
Z)
lc


R-15
Monuments


Figure 3-14: Unit volume change rates for the period from

Jupiter Inlet in Palm Beach County


1996 to 1997 just south of













Shoreline Change per Monument in Palm Beach County between May 1995 & April 2004


R-1 5
Monuments


Figure 3-15: Shoreline change rates for the combined period from
south of Jupiter Inlet in Palm Beach County


1995 to 2004 just


200 F


r
c
E
C
0
S

a.


a)
E
0
C-


150


-100


Unit Volume Change per Monument in Palm Beach County between May 1995 & April 2004
w n-----------------,---,---,--


-150


-200 -


R-15
Monuments


R-16


Figure 3-16: Unit volume change rates for the combined period from 1995 to 2004 just
south of Jupiter Inlet in Palm Beach County


E
c

0

C)

a .
c



t--
C


0
-C
d


R-17


Accretion














Jupiter Inlet

Erosion












Shoreline Change per Monument in Palm Beach County between August 2001 & October 2002


E

CL





0


R-10 R-11 R-12 R-13 R-14 R-15 R-16 R-17 R-18 R-19 R-20 R-21
Monuments

Figure 3-17: Shoreline change rates for the period from 2001 to 2002 in Palm Beach
County


Unit Volume Change per Monument in Palm Beach County between August 2001 & October 2002
200 ,


150-

Accretion
) 100-
E
0









I -100 .
q 0- -- -- -- - -- -




i -1 0 0 . . .* ; ; .


R-10 R-11 R-12 R-13 R-14 R-15 R-16 R-17 R-18 R-19 R-20 R-21
Monuments

Figure 3-18: Unit volume change rates for the period from 2001 to 2002 in Palm Beach
County














CHAPTER 4
SEDIMENT BUDGET

4.1 Sediment Budget Methodology

4.1.1 Sediment Budget Equation

This section presents the development of the sediment budget methodology applied

to Jupiter Inlet. The elements included in the budget account for all possibilities of

sediment entering, leaving or being stored within the area of consideration (Rodriguez

and Dean, 2005). For Jupiter Inlet, the volumetric storage elements include the updrift

and downdrift beach systems and the ebb tidal shoal.

To fully illustrate the sediment budget methodology, the rates of volume change on

the updrift and downdrift beaches will be described using all possible volume storage

components as displayed in Figure 4-1. Later, the components that are unimportant to

Jupiter Inlet will be deleted. The rate of volume gain for the updrift beach is described in

Equation (4-1) and the rate of volume gain for the downdrift beach is described in

Equation (4-2) as follows (Dean, 2005):

r V = QIN + QUos,UB -- QEBB,UB QST, UB QBB,UB (4-1)
dt UB

dV
d )B :-QoUT + QOS,DB E- QEBB,DB QST,DB QBB,DB + QNOUR + QDR (4-2)
Sdt DB

where:

or = volumetric rate at which sediment is accumulated in the updrift
dt )UB DB
or downdrift beaches, respectively,









QIN or QoUr = volumetric rate at which sediment enters the updrift beach or leaves
the downdrift beach through littoral transport, respectively,
Qos,UB or Qos,DB = volumetric rate at which sediment enters the updrift or downdrift
beaches through onshore transport, respectively,
QEBB, UB or QEB,B D= volumetric rate at which sediment is accumulated in the ebb tidal
shoal from the updrift or downdrift beaches, respectively,
Qsr,UB or QST,DB = volumetric rate at which sediment is accumulated in the interior
sand trap from the updrift or downdrift beaches, respectively,
QBB,UB or QBB,DB = volumetric rate at which sediment is accumulated in the back bay
region from the updrift or downdrift beaches, respectively,
QNOUR = annual average volumetric nourishment rate of the downdrift beach with
sediment provided from outside of the system, and
QDR = volumetric rate at which sediment is dredged from the interior sand trap.

Combining Equations (4-1) and (4-2) yields the total volumetric rate at which

sediment is stored on the updrift and downdrift beach systems:

-) + = Qi QoUr +Qos,UB +OS,DB -QEBBUB QEBB, DB
dt dt DR (4-3)
QSB STDB BB,UB BB,DB NOUR +DR

The sediment budget is based on the premise that, if the inlet were non-existent, the

processes along the same shoreline distance updrift and downdrift of the inlet would be

identical. Therefore, over the same longshore distances, the beaches updrift and

downdrift should be eroding or accreting at the same rate (Dean, 2005). Theoretically,

with no inlet, the volume changes on equal lengths of updrift and downdrift beaches

would be equal; that is, each would be one half of the total volume change:


=dV = (QN -Qour +Qos,U +QOS,DB) (4-4)

However, due to the presence of the inlet and sediment likely being transported into the

inlet channel, not all sediment coming from the updrift side of the inlet is transported to

the beach downdrift of the inlet. Therefore, the difference between the actual volume








change rate that has occurred on the downdrift beach and the theoretical volume change

rate of the downdrift beach represents the yearly excess or deficit of nourishment that has

been placed on the downdrift beach, as follows:

DIFFERENCE N QoUTr + Qos,,B + QOS,DB) (4-5)
dt DB 2

In this context, a positive QDIFFERENCE value would indicate that there is a quantity of

sediment on the downdrift beach in excess of the amount that would be there in the

absence of the inlet, whereas a negative value would represent a deficit of sediment.

Rearranging equation (4-3), it can be seen that:

I (QIN Qour + QoS,UB + QOS,DBR)
1 (dV + (+dV B+dV B (+dV (cdV (4-6)
-- + -- + QNO UR
2 dti dt dtc dt ) dt)R

where the following substitutions have been made for the ebb tidal shoal, sand trap, and

back bay elements:

/ V = QEBB,UB + QEBB, DB
dt EBB
V = Qsr,UB +QST,DB -QDR (4-7)
dt ST
(dVy
dt V = QBB,UB + QBB,DB
Sdt BB

For Jupiter Inlet, the volume changes of the sand trap are approximated as zero

because the sediment that flows into the trap is then dredged and placed within the

system as nourishment on the beach. This means that, on average, accumulation of sand

in the trap is not counted as a loss to the beach. Consequently, the nourishment placed on

the beach from the sand trap is eliminated from the equation as well because only









nourishment coming from outside of the system needs to be accounted for. Also, the

backbay element is approximated to be zero because the sediment that flows into, out of,

and is stored in that region is relatively small when compared with the other elements, as

shown in the last row of Table 4-1.


Figure 4-1: Definition diagram displaying Jupiter Inlet along with all possible
components in the sediment budget equation

Records of ebb shoal volumes tend to be limited and their reliability is uncertain.

For this reason the sediment budget will be computed twice, once including the ebb shoal

volume change rate data, and once assuming the ebb shoal volume change rates to be

negligible and therefore excluding them from the equation.

With all the necessary volumetric elements being accounted for including the ebb

shoal volume change rate, the excess (positive QDIFFERENCE value) or deficit (negative









QDIFFERENCE value) of nourishment on the downdrift beach of Jupiter Inlet is found based

on the following equation:

1 (dV dV\ ((4dV-
QDIFFERENCE \ d + QNOUR (4-8)
dt dt dt
DB ) UB EBB

It consists of only the volumetric rates of change occurring on the north and south

beaches and in the ebb tidal shoal, as well as the volumetric rate at which nourishment

from outside of the system is placed on the downdrift beach, as shown in Figure 4-2.

The sediment budget equation for Jupiter Inlet in which the ebb shoal volume

change rate is excluded is similar to equation (4-8) with the only difference being that it

excludes the ebb shoal term as follows:


DIFFERENCE = 2 D QNOURD (4-9)
2 dt dt

Table 4-1: Annual mean sand volumetric transport rates in the eastern zone (Source:
Patra & Mehta, 2004, p. 11)
Transport from/to Volumetric rate
(m3/yr)
Net southward littoral drift 176,000
Entering the channel from littoral drift 46,000
Bar-bypassed around the inlet 128,000
Bypassed by dredging from JIDa trap and 33,000
ICWW
Tidally bypassed by entering and then 4,000
leaving the channel
Ejected from the channel to offshore by 4,000
ebb flowb
Transported offshore from drift by ebb 2,000
flow
Transported to ICWW channels north and 4,000
south of inlet
Transported to central embayment 1,000
a Jupiter Inlet District.
b Deposited seaward of the littoral system.



































Figure 4-2: Sediment budget components specific to Jupiter Inlet

4.1.2 Method for Evaluating Sediment Budget

In order to determine the rate of excess or deficit of nourishment being placed on

the beach downdrift of Jupiter Inlet, several steps were followed. First, the beach profile

data were collected from records available on the Florida Department of Environmental

Protection's website and from records kept by the Jupiter Inlet District. The FDEP data

were analyzed for two different shoreline distances updrift and downdrift of Jupiter Inlet.

The first analysis conducted focused on a distance of 17.4 km north of the inlet,

beginning at Monument R-75 in Martin County, and extending a distance of 8.53 km

south of the inlet, ending at Monument R-40 in Palm Beach County. The second distance

of shoreline that was analyzed covered equal distances of shoreline updrift and downdrift

of the inlet, beginning at Monument R-1 12 in Martin County, 7.25 km north of the inlet,









and ending just past Monument R-36, 7.25 km south of the inlet. For each shoreline

distance analyzed, the FDEP data were examined over three periods. The average

periods were from 1974 to 1986, 1986 to 2002, and 1974 to 2002. These average periods

were determined based on the survey dates that were available for each county,

specifically 1976, 1982 and 2002 for Martin County and 1974, 1990 and 2001 for Palm

Beach County. The JID data were analyzed for a short shoreline distance within Palm

Beach County, beginning at Monument R-10 which is almost 0.56 km north of the inlet,

and ending at R-15 which is approximately 0.50 km south of the inlet. The JID data were

analyzed for one period only, from 2001 to 2002. From these beach profile data, values

of the cumulative volumetric rates of change of sediment being stored on the updrift and


downdrift beaches, rdV) and dV respectively, for the defined distances and
S UB dt DB

time periods were determined as described in Section 3.1.

To calculate the rates of beach nourishment, records of nourishment on the updrift

and downdrift beaches were collected. Because the sediment budget methodology is

focused on analyzing the volumetric rates of change that occur on the downdrift beach

and only accounts for changes that would occur naturally, nourishment on the updrift

beach does not appear in the final sediment budget calculation. Therefore, volumetric

rates of nourishment that had occurred on the beaches updrift of the inlet were subtracted

from the values of volumetric rates of change of sediment stored on the updrift beach.

The records of nourishment on the downdrift beaches were added into the sediment

budget equation as QNOUR in cases where the sediment used for nourishment came from

outside of the beach system. The nourishment from outside of the beach system

consisted mainly of sediment dredged from the Intracoastal Waterway deposition basin.









The sediment collected in this basin is believed to have come from sources other than

directly from the inlet, including the channel and the Loxahatchee River system.

Volumes dredged from the JID sand trap and from the ebb tidal delta to be used as

nourishment on the downdrift beach were not included when calculating the final rates of

nourishment in the sediment budget equation because both the sand trap and the delta

were considered to be included in the system.

Records of volume measurements of the ebb tidal shoal are scarce. Only one

compilation of volume measurements was found (Dombrowski, 1994), and this included

measurement estimations only through 1993. The early data show wide variability, and it

is uncertain if this is due to volume changes actually experienced or due to limitations in

the quality of surveys used to obtain the volumes. Three of the measurements relevant to

the study time period were used to construct a best-fit trend line, as shown in Figure 4-3.

The slope of this line displayed a slightly positive volumetric rate of change which was


used as in the sediment budget equation. Because there were very few reliable
Sdt EBB

measurements, the ebb tidal shoal volumetric rate of change was assumed to be constant

as obtained from the best-fit line for all periods analyzed in the sediment budget.

The 2000 and 2001 ebb tidal shoal survey data that were taken from the Palm

Beach County Department of Environmental Resources Management website were also

analyzed to find a volumetric rate of change estimate in order to assess the accuracy of

the above estimate. A grid was created in MATLAB, and using measurements from the

surveys, interpolations were made to find depths at each point of the grid. From this

depth-grid, contour plots were created for each year, as shown in Figures 4-4 and 4-5. As

displayed in Figure 4-6, the 2000 depth elevations were then subtracted from the 2001







47


depth elevations in order to find the difference in depths between the two years. As the

exact area of the ebb delta was uncertain, different areas were used to calculate the

volume changes. These areas are shown as boxes in Figure 4-6. Examining the area

contained in the large box, a volume of -52,200 m3 was estimated, implying that the delta

had eroded between 2000 and 2001. Adding together the volumes estimated from the

three smaller boxes, a total volume of +15,208 m3 was estimated, suggesting that the

delta had accreted from 2000 to 2001. Based on these calculations, it is obvious that ebb

tidal shoal volume estimates vary greatly in accordance with the assumption of the area

that is considered to constitute the ebb shoal. This could explain the variability in the

measurements that were found in Dombrowski (1994). It was also the reason that the

sediment budgets were computed both with and without the ebb shoal component.


Jupiter Inlet Ebb Delta Volumes Best-fit line
with a slope qf
4,245.7
700000
y = 4285 7x 8E+06
600000

500000

400000

300000 t -

200000

100000 -

0
1880 1900 1920 1940 1960 1980 2000
Year

Figure 4-3: Plot showing measurements of Jupiter Inlet's ebb delta volumes, highlighting
the three that were chosen to construct a best-fit line







48



x 10 depth contours after interpolation for delta 2000 (m)
2.91 ,
-2

2.905 -3

-4
2.9-
,-5

2.895 --6
--6
"N "- -7
2.89
'I -8

2.885


2.88- -10

-11
2.875 -
-12
2.92 2.925 2.93 2.935 2.94
x(m) x 10

Figure 4-4: Jupiter Inlet ebb tidal shoal depth contours for the year 2000


x 106 depth contours after interpolation for delta 2001(m)
-1
2.91


2.905 .
%,4
2.9


2.895 '


2.89 --
,I]

2.885
.9

2.88- '

.1 1
2.875 -
1-12
2.92 2.925 2.93 2.935 2.94
x(m) x 106

Figure 4-5: Jupiter Inlet ebb tidal shoal depth contours for the year 2001











x 105 Shore line/delta changes (2001-2000)(m)

2.9- --
I '1.


2. 1- .5







2.898 '







2.921 2.922 2.923 2.924 2.925 2.926 2.927 2.928 2.929 2.93 2.931
x x 10

Figure 4-6: Jupiter Inlet ebb tidal shoal difference in depth contours (2001-2000) used
for volume calculations

After deriving all of the volumetric quantities for the necessary sediment budget

components, these quantities were inserted into the sediment budget equations derived in

order to solve for QDIFFERENCE. The sediment budget components are presented in Tables

4-2, 4-3, and 4-4 with the appropriate quantities inserted where required. As discussed in

Chapter 2, the sediment budgets that were created based on the FDEP profile data are

presented as the "FDEP sediment budgets", and the sediment budget that was created

using the JID profile data is presented as the "JID sediment budget".

4.1.3 Effect of Length of Beach on Sediment Budget Calculations

The result of a sediment budget equation may vary depending on the equal lengths

of updrift and downdrift shoreline that are chosen for the analysis. By selecting short

distances of shoreline updrift and downdrift of the inlet, the immediate effects on the









downdrift beach caused by the inlet or by recent nourishment events will be seen,

whereas selecting larger distances of shoreline will display if and how the inlet affects the

shoreline and beaches further downdrift. If the sediment budget analysis is carried out

for a distance of shoreline covering downdrift areas of shoreline where erosion is

significant, the result of the sediment budget will likely show a large deficit of sediment

on the downdrift beach if the updrift beach is not experiencing similar erosive trends.

However, if the analysis covers a distance of shoreline that displays differing amounts of

accretion and erosion, the result of the sediment budget will show a surplus or deficit of

sediment on the downdrift beach dependent on whether the accretive or erosive trends

dominate when compared with the updrift beach's behavior.

Specifically for Jupiter Inlet, if availability of data allow, the minimum length of

beach that should be chosen for analysis is approximately 1 km updrift and downdrift of

the inlet. Since the length of the nourished beach downdrift of the inlet is nearly 0.5 km,

a 1 km shoreline distance should be a sufficient length with which to observe the effects

of the natural spreading of nourishment. Also, this shoreline distance is approximately

four times the length of the jetty that is south of Jupiter Inlet, meaning that the immediate

effects of the inlet and its jetties should be evident within this proximity.

4.2 FDEP Sediment Budget Components

As mentioned previously, two sediment budgets were developed based on the

FDEP beach profile data with the only difference between them being the length of

shoreline included in the analysis. Presented in Table 4-2 are the sediment budget

components for the long shoreline analysis which began at Monument R-75 in Martin

County and extended southward to R-40 in Palm Beach County, covering approximately

26 km of shoreline. Table 4-2 presents the volume changes per year of the beaches









downdrift and updrift of Jupiter Inlet, the volumetric rate of change of the ebb tidal shoal,

and the volumetric rate of nourishment placed on the downdrift beach with sediment

from outside of the system. The last two columns display the estimates of the excess or

deficit of nourishment on the downdrift beach on a yearly basis for the given period, with

the first including the ebb shoal volume estimates as in Equation (4-8) and the second

excluding the ebb shoal volume estimates as in Equation (4-9).

Table 4-2: FDEP sediment budget components for long analysis
Period (dV/dt)DB (dV/dt)uB (dV/dt)EBB QNOUR DIFFERENCE DIFFERENCE
(m3/yr) (m3/yr) (m3/yr) (m3/yr) (Including (Excluding
ebb shoal ebb shoal
volume volume
estimates) estimates)
(m3/yr) (m3/yr)
1974- 800 -206,700 4,300 18,500 110,900 113,000
1986
1986- 152,700 -142,400 4,300 24,300 157,600 159,700
2002
1974- 55,300 -173,200 4,300 20,900 122,600 124,700
2002 ___________

The second FDEP sediment budget estimate, which is the more accurate of the two

FDEP budgets, is based on the short shoreline analysis which began at Monument R-1 12

in Martin County and extended southward just past R-36 in Palm Beach County. This

budget is more accurate because it analyzes equal distances of shoreline updrift and

downdrift of the inlet, each 7.25 km in length, which is appropriate according to the basis

of the sediment budget equation. As stated, according to this basis, in the absence of an

inlet, the volume changes over the same distances of shoreline updrift and downdrift

should be equal. The sediment budget components for this analysis are presented in

Table 4-3 in the same order as in Table 4-2.









Table 4-3: FDEP sediment budget components for short analysis
Period (dV/dt)DB (dV/dt)uB (dV/dt)EBB QNOUR DIFFERENCE DIFFERENCE
(m3/yr) (m3/yr) (m3/yr) (m3/yr) (Including (Excluding
ebb shoal ebb shoal
volume volume
estimates) estimates)
(m3/yr) (m3/yr)
1974- 6,900 1,000 4,300 18,500 10,100 12,200
1986
1986- 114,300 20,900 4,300 24,300 56,700 58,900
2002
1974- 47,000 4,700 4,300 20,900 29,500 31,600
2002 ___________

4.3 JID Sediment Budget Components

The sediment budget based on the data provided by JID is presented in Table 4-4.

This analysis covers a small distance of just over 1 km of shoreline and extends from

Monument R-10 in Palm Beach County, north of the inlet, to R-15, south of the inlet.

Consistent with both of the FDEP analyses, it can be seen that the downdrift beach

volume change rate is positive.

Table 4-4: JID sediment budget components
Period (dV/dt)DB (dV/dt)UB QEBB QNOUR DIFFERENCE DIFFERENCE
(m3/yr) (m3/yr) (m3/yr) (m3/yr) (Including (Excluding
ebb shoal ebb shoal
volume volume
estimates) estimates)
(m3/yr) (m3/yr)
August 83,300 -2,600 4,300 49,600 65,600 67,800
2001-
October
2002

4.4 Sediment Budget Results

The equations developed in Section 4.1 provide the basis for the calculation of the

excesses or deficiencies in nourishment on the downdrift beach that prevent the balance

of the sediment budget. If the sediment budget were balanced, the value of QDIFFERENCE









would be equal to zero. A QDIFFERENCE value that is negative corresponds to a need for

additional nourishment whereas a value that is positive means that more sediment exists

on the downdrift beach than is needed for the volume changes on the updrift and

downdrift beaches to balance out. According to the short FDEP analysis presented in

Table 4-3, over the long-term period of 1974-2002 an excess of 29,500 m3/yr of sediment

existed on the downdrift beach when the ebb shoal volume estimates were included in the

analysis, and an excess of 31,600 m3/yr existed on the downdrift beach when the ebb

shoal volume estimates were excluded. The two shorter periods included within the total

period also display excess volumes on the downdrift beach and can be seen in the last two

columns of Table 4-3. According to the JID sediment budget analysis presented in Table

4-4, between August 2001 and October 2002 an excess of 65,600 m3/yr of sediment

existed on the downdrift beach when the ebb shoal volume estimates were included in the

analysis, and an excess of 67,800 m3/yr existed on the downdrift beach when the ebb

shoal volume estimates were excluded. These positive quantities support the results of

the FDEP sediment budget estimates. The sediment budget results are summarized in

Table 4-5.

Table 4-5: Short FDEP and JID sediment budget results
DIFFERENCE DIFFERENCE
Sediment Budget (Including ebb shoal (Excluding ebb shoal
volume estimates) volume estimates)
(m3/yr) (m3/yr)
Short FDEP 29,500 31,600
JID 65,600 67,800














CHAPTER 5
SUMMARY AND CONCLUSIONS

5.1 Summary

Due to the shoaling of Jupiter Inlet, a tidal entrance along the southeastern coast of

Florida, and the resulting erosion of its adjacent beaches since its stabilization, there has

been an extensive history of dredging of the inlet's sand trap and nourishment of the

downdrift beach. The implementation of a management plan in 1992 has made specific

criteria to be followed in order to control the shoaling within the inlet and to minimize

surrounding beach erosion. The objective of this study was to develop a sediment budget

taking into account sediment-storing components relevant to Jupiter Inlet in order to

assess the role of downdrift beach nourishment.

In order to perform this study, beach profile data were compiled from two sources,

the Florida Department of Environmental Protection (FDEP) and the Jupiter Inlet District

(JID). Additional data collected for the sediment budgets included dredging,

nourishment and ebb shoal data. The data collected for the FDEP sediment budgets were

examined for three time periods, covering 1974 to 1986, 1986 to 2002 and 1974 to 2002.

The JID survey data that were examined covered time periods of 1995 to 1996, 1996 to

1997, and 1995 to 2004 for Monuments R-13 to R-17 downdrift of the inlet, and a period

of 2001 to 2002 for Monuments R-10 to R-21.

From the beach profile data, shoreline changes and sediment volume changes over

the selected periods of time were calculated for the beaches updrift and downdrift of the

inlet. These calculations took into account profile data uncertainties. Volume change









sensitivity to the assumed depths of closure was also examined. The shoreline and

sediment volume changes were calculated for Monuments R-75 to R-127 between 1976

and 1982, 1982 and 2002, and 1976 and 2002 for Martin County and for Monuments R-1

to R-40 between 1974 and 1990, 1990 and 2001, and 1974 and 2001 for Palm Beach

County based on the FDEP profile data. The same sets of calculations were made for

Monuments R-13 to R-17, just downdrift of the inlet between May 1995 and May 1996,

May 1996 and March 1997, and May 1995 and April 2004 and for Monuments R-10 to

R-21 between August 2001 and October 2002 based on the JID profile data.

The basis of the development of the sediment budget was that volume changes over

the same distances of shoreline updrift and downdrift of the inlet would be identical in

the absence of the inlet, and therefore a sediment balance could be created based on this

principle (Dean, 2005).

5.2 Conclusions

1. Based on the shoreline change calculations made from the FDEP profile data,
although both shoreline advancement and recession occur, the overall trend is seen
to be shoreline advancement downdrift of the inlet.

2. Based on the volume change calculations made from the FDEP profile data, the
areas of shoreline displaying volumetric accretion outnumber the areas of shoreline
displaying erosion on the beach downdrift of the inlet.

3. The shoreline change rates based on the 1995, 1996, 1997 and 2004 JID profile
data taken downdrift of Jupiter Inlet show varying shoreline advancement and
recession for the first two intervals (1995-1996 and 1996-1997), but the shoreline
changes display recession for the last interval (1995-2004). The shoreline change
rates calculated based on the JID profile data between August 2001 and October
2002 display high rates of accretion on the downdrift beach, with erosion occurring
only at Monument R-20.

4. The volume change rates based on the 1995, 1996, 1997 and 2004 JID profile data
taken downdrift of Jupiter Inlet display mainly volumetric erosion. The volume
change rates calculated based on the JID profile data between August 2001 and
October 2002 display high rates of accretion on the downdrift beach, with erosion
occurring only at Monument R-20.









5. There is substantial variability in the results of the sediment budgets depending on
whether or not ebb tidal deltas are included in the calculations. When the ebb tidal
delta volume changes were excluded from the calculations, the results of all
sediment budgets were about 2,100 m3 per year higher than when they were
included in the calculations. Also, the variability within the sediment budgets is
dependent on which ebb tidal delta volume estimations are assumed to accurate and
used in the calculations. As discussed in Chapter 4, depending on the area chosen
as the ebb tidal delta, the volume change estimations vary greatly, ranging from
high rates of accretion to high rates of erosion.

6. Volume change rates showed only slight sensitivities to the depth of closure chosen
for the calculations. The largest sensitivity calculated showed an average
difference between rates was 1.68 m3/m per year. Most other calculations showed
average differences between rates to be less than 1 m3/m per year. These
sensitivities are due to the fact that the distance to the depth of closure alters
depending on the depth of closure chosen, and the distance to this depth is the
seaward extent of the volume calculations.

7. For the sediment budgets developed, the consistent result was that over all time
periods considered there has been an excess amount of sediment existing on the
downdrift beach when compared with approximately the same shoreline distance of
beach updrift of the inlet. Two of the three sediment budgets that were created are
more accurate based on the fact that they analyze nearly equal distances of
shoreline updrift and downdrift of the inlet. These two budgets are the short
"FDEP sediment budget" and the "JID sediment budget".

a. When ebb tidal delta volume estimates were excluded from the budget,
overall excesses in sediment on the downdrift beach based on the short
"FDEP sediment budget" from 1974 to 2002 were 31,600 m3/yr. Based on
an average seaward distance of 250 m over a 7.25 km distance of
shoreline, this result represents an average accretion rate of just 1.74 cm/yr
over the entire area.

b. When ebb tidal delta volume estimates were excluded from the budget,
overall excesses in sediment on the downdrift beach based on the "JID
sediment budget" from August 2001 to October 2002 were 67,800 m3/yr.
Based on an average seaward distance of 250 m over a 500 m distance
shoreline, this result represents an average accretion rate of about 0.54
m/yr over the entire area.

c. When ebb tidal delta volume estimates were included in the budget,
overall excesses in sediment on the downdrift beach based on the short
"FDEP sediment budget" from 1974 to 2002 were 29,500 m3/yr. Based on
an average seaward distance of 250 m over a 7.25 km distance of
shoreline, this result represents an average accretion rate of only 1.63
cm/yr over the entire area.









d. When ebb tidal delta volume estimates were included in the budget,
overall excesses in sediment on the downdrift beach based on the "JID
sediment budget" from August 2001 to October 2002 were 65,600 m3/yr.
Based on an average seaward distance of 250 m over a 500 m distance of
shoreline, this result represents an average accretion rate of about 0.53
m/yr over the entire area.

5.3 Recommendations for Further Work

In order to increase the accuracy of future sediment budget analyses, the following

recommendations should be considered:

1. Profile survey data should be taken yearly of Monuments R-3 to R-21 so that there
are nearly equal shoreline distances updrift and downdrift of Jupiter Inlet. Equal
shoreline distances increase sediment budget accuracy. In addition, by having
survey data from each year, a more accurate rate of accretion or erosion can be
determined. Also, rates that might seem unnaturally high or low could be linked to
certain storm events or weather patterns that might go unnoticed when there is a
much longer period of time in between surveys.

2. Regular surveys of the ebb tidal delta need to be taken yearly as well, preferably
near the same time that the aforesaid profile surveys are taken. The area that the
ebb tidal delta covers needs to be defined so that the yearly measurements can be
taken in consistent locations, thus minimizing the resulting volume calculation
discrepancies.


















APPENDIX A
FDEP LONG BEACH PROFILES FOR MARTIN AND PALM BEACH COUNTIES


Monument R-75

-1976
--- 1982 -
........2002











S, 's Depth of Closure


40 I I I I I
0 200 400 600 800 1000
Distance from Monument (m)


1200 1400
1200 1400


Figure A-1: Profiles for Monument R-75 in Martin County.


4

2

0

--2

S-4

I -6
)
Q













8

6

4

2

I0
z
S-2

t -4
o
I -6

.-8

-10

-12


0 200 400 600 800 1000
Distance from Monument (m)

Figure A-2: Profiles for Monument R-78 in Martin County.


8

6

4

2

0
z
0 -2

S-4

1 -6

S-8


1200 1400


Monument R-81


Distance from Monument (m)

Figure A-3: Profiles for Monument R-81 in Martin County.


Monument R-78

S- 1976
- ---1982 -
2002








------------ -------------- 7-7 -------- --
-.... .......



Depth of Closure




-








60







Monument R-84

1976
6 --- 1982
2002
4








0 -- ---------------- ------







-10

-12
-| 2 L .. L L I .







0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-4: Profiles for Monument R-84 in Martin County.


Monument R-87
8
-1976
........ 6... .... ... .... ...... .... .. -1982.. ....
2002
4-



S- --- ----8. --- -------------------------- --------



S-4
-. . ... . . . . . : . i . ..





















200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)
200 400 600 800 1000 1200 1400 1600


Figure A-5: Profiles for Monument R-87 in Martin County.








61






Monument R-90

S-- 1976
.. .---1982 -
2002








------------------ -of Closure----------------------



Depth of Closure


I I I I I
200 400 600 800 1000
Distance from Monument (m)


1200 1400 1600


Figure A-6: Profiles for Monument R-90 in Martin County.


Monument R-93




I--------- I -----------------------------------------
: -- 1976
.... .. .. .. .. ... .- 1982 -
........2002












.: ''',, .... Depth of Closure


-14 I ii I I I


0 200 400 600 800 1000
Distance from Monument (m)


1200 1400 1600


Figure A-7: Profiles for Monument R-93 in Martin County.


8

6

4

g2


z
0

S-2

-4

6 -6
4)


8

6

4

2

0
z
S-2

-4

1 -6
g








62






Monument R-96
8,I I i i I
1976
6 ---1982
S2002
4

2

0 ------------ ------ ------------------ --------------

-2 -

4 '- 7

6 -8






-1 2 . . .

-14 I I I i
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-8: Profiles for Monument R-96 in Martin County.


Monument R-99
8
S --1976
6 . . .. .. .. -- 1982 -
....2002
4

2





4 -----7---7-- ----- --------- --- ---

-6g -

S ......... .. ....Depth of C closure .. .......



-12 "

-14 I I
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)


Figure A-9: Profiles for Monument R-99 in Martin County.


















8

6

4

g2



z
-2

-4

0
-6

S-8


-10

-12

4IA


Monument R-102

1976
-- 1982
2002


0 200 400 600 800 1000 1
Distance from Monument (m)


Figure A-10: Profiles for Monument R-102 in Martin County.



Monument R-105
8

6

4




8 0---------------------------------------

|o ----------- ------------ 777777777




6 --
-84 . . .. .. .. .. .. .. .. -
: ... ..... Depti






-12 '

-14 i i
0 200 400 600 800 1000 1
Distance from Monument (m)


Figure A-11: Profiles for Monument R-105 in Martin County.


200 1400 1600


. .. .. .... Depth of Closure :


-


-

-

-


E I I
















Monument R-108

1976
S.. -- 1982
2002







-------------- ----------- -7. -- of --.-u :----





Depth of Closure


200 400 600 800 1000
Distance from Monument (m)


Figure A-12: Profiles for Monument R-108 in Martin County.


Monument R-111


8

6

4

2

0
z


-4

S-6


1200 1400 1600


-14 I I I I II -


0 200 400 600 800 1000
Distance from Monument (m)


1200 1400 1600


Figure A-13: Profiles for Monument R-1 11 in Martin County.


8

6

4

g2


z
0

--2
-4


0
6 -6
4)


: --1976
.. ... ....... : .... .. 1982 -
S2002




P -




-D- eh- ----- of-C



'^ Depth of Closure
.:.. .. ... ... ....,. .. .. .,...., ~ ^ ^ .. ., ... ,.. ..., .. .















Monument R-114

--1976
-- 1982
2002


0 200 400 600 800 1000 1
Distance from Monument (m)

Figure A-14: Profiles for Monument R-1 14 in Martin County.


Monument R-117
8

6 ... .

4 -: : .... ..... -



S0 ----------- --- -- ----------------



-4




-1 0 .. ........ . .... .. .. .......... .... .. ... .. ... .. ...... .. ... ... .. ... ...
-6



-10

-12 .

14 I i i I I
0 200 400 600 800 1000 1
Distance from Monument (m)

Figure A-15: Profiles for Monument R-1 17 in Martin County.


8

6

4

g2


z

-4
0


6
-8


-10

-12

IA


200 1400 1600


200 1400 1600


1-
- .


-, --- ------- -. Depth of .... Closure


S------------- ----- -----------------------------------


i's :Depth of Closure
.. - - ^ .


: --1976
---1982
.........2002










----------------Depth of Closure

Depth of Closure


-


-

-

-


E I I








66






Monument R-120

1976
6 ---1982
2002
4

2

0 ------------------ -------------------- --------------






S-6 '
I- 6 Depth of Closure


-10 -

-12 -. . .

-14 L L i
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-16: Profiles for Monument R-120 in Martin County.


Monument R-123
8
: -- 1976
6 .. . . : . .. 1982 -
S2002
4




|0 --------------*---- -----"----------------------------

2 . . . ... ..... ... . .. . . .. .. ... .. . . .... ...
-2


o
*-----.--- ---- ---7 -7 77 7-7--7-7-
3 -4 ... .. .. : .... .. .. ....... 7 7 7... % 7. 1 7 -

*g-6






-12

14 : I I L I
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)


Figure A-17: Profiles for Monument R-123 in Martin County.








67






Monument R-126
8 I------------------------ I I I
1976
6 ... ---1982
2002
4

2



S --------------------------- --------------
-4


-6 -
S- Depth of Closure
-l O . ; .F. . . . . ... .

-10-

-12 .. .
14I I I i
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-18: Profiles for Monument R-126 in Martin County.


Monument R-1
8
: -- 1974
6 . . .. .. .. -- 1990 -
....2001
4
4 ......... .. .... ...... ... .. ... ... .. . . .. ... .. .... _







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


g -6 .........Depth of Closure

1 2 .8 .. .. ....... ....i . .. ... .. .... ... .. .. .... .. ... ...... .. ....... . . .. .... .. .. : .. ... .......




-12-

14 : I L I
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-19: Profiles for Monument R-1 in Palm Beach County.








68






Monument R-3
8 I------------------------ I I I
1974
6 ---1990
2001
4



0 -----------------------------------------

-2 -

-4 .. --- -------- 7 ---------- .. --- ---------------

S6 6.-- Depth of Closure.
... .


-10 -

-: : .,. . .
-12

.14 I I I i
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-20: Profiles for Monument R-3 in Palm Beach County.


Monument R-6
8
: -- 1974
6 .. . . : . .. 1990 -
S2001
4

2-

0 ----- ------------------------ -------
-2 0


-4 .
> -2 -.--------------------
.8 .. .. -- ... ... .. .. ........ ...... . .





-10 -
S-6 ......... ... ... .... .D epth of C closure ....... .. .......


144
1 2 1 L L L


0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-21: Profiles for Monument R-6 in Palm Beach County.








69






Monument R-9
8 I------------------------ I I I
1974
6 ---1990
'2001
4



0 --------------------- ---------------------------


0 ... ----.. -.... .-,.. .....---
-4

-6 : Depth of Closure

-10 :



-12 -
-142 I I I i
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-22: Profiles for Monument R-9 in Palm Beach County.


Monument R-12
8
0: -- 1974
6 .. . . ... .. -- 1990 -






0 --------- ---------------- ------------------------
._ .... ........ .. .. ..... .... .. .. .... ... .. .... ...... .... .. ..... .... .. .... ....
-2 --- ------ -- -



S-6 '' ,, ... .... .... Depth of Closure .......





-12 "

1 4 1 I I
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-23: Profiles for Monument R-12 in Palm Beach County.








70






Monument R-15
8 I------------------------ I I I
S-- 1974
6 ... ---1990 -
2001
4

j2

S- ----------------------------------------------------
2 -
-. -', _" -_ . . . . - _ _ _
-4 -

S6 -.., : Depth of Closure



-12

-10
-12 . .. .


0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-24: Profiles for Monument R-15 in Palm Beach County.


Monument R-18
8








0 -------------------------- ---------------------
-2 -- 97





14

,- ..6. Depth of Closure
6 8 : . .. .... . ... .... .. ...... .







-1 2 . .. .. .. . .. ... ... .. . .. .... C... ... . .......

-14 I i I I
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-25: Profiles for Monument R-18 in Palm Beach County.
















8

6

4

2


z
1 -2




-8
5 -8


Monument R-21


.1 4 '0 i i i i i
0 200 400 600 800 1000 1200
Distance from Monument (m)

Figure A-26: Profiles for Monument R-21 in Palm Beach County.


Monument R-24


8

6

4

g2


z
. -2

S-4

S-6

-8

-10

-12

-14


0 200 400 600 800 1000 1200
Distance from Monument (m)

Figure A-27: Profiles for Monument R-24 in Palm Beach County.


1400 1600


1400 1600


S- --1974
S ........ ... .. ... ........ .. .............. ...... .--- 1990 -
S: 2001
N










S .,. .. ........ ... ...... -.. .. : .......... .. .: .. .. D e p th o f C lo s u re . .






. .







72






Monument R-27
8 I------------------------ I I I
1974
6 .. .---1990 -
2001
4



0 ----- .------------- ----------------------------

-2
S ---------------------------------- -----
I. -^^------,--------
-4-

S-6 Depth of Closure



-14
-10 .: "

-12 -. N -

0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-28: Profiles for Monument R-27 in Palm Beach County.


Monument R-30
8
: --1974


4
0 .. . : . .-. .. - 1990 -



0 2 .... ... .. .... ...... .... .. ... .... .. .. .. ...

-2 -



2 ... .. ..... . .... ... ..... .. .. ... .... ....
-4

-6 -
Depth of Closure
-8

1 0 . .. .. . .. . .. .. .. .. .. .. .. . . . .. . ... .. .. ... .. .. .. .. .. .... .. .. .



-14 '-
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-29: Profiles for Monument R-30 in Palm Beach County.







73






Monument R-33
8 I------------------------ I I I
1974
6 ---1990
S2001
4

2


S ---------------------- -----------------------------
-2 - -
-4 -

-6 Depth of Closure


S.... .. ........ ... .. .. ... ..
-.8

-10 -

-12 .

.14 I I I i N
0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-30: Profiles for Monument R-33 in Palm Beach County.


Monument R-36

: -- 1974
6 . .. . . : . 7 --- 1990 -
2001
4





-6 -
S -2 ... .. ... ....... ..... ... ...... ... .... ................ ...... .. ....... ....... ... ... ...



-4 .. .. : .. .... .... .. . .... .. .. .... . .. .. .. .

S ......... ........ \ ......
: *.g -6Depth of Closure


-10 .

-12 ,,. .


0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-3 1: Profiles for Monument R-36 in Palm Beach County.








74






Monument R-39

-1974
6 ---1990 -
S2001
4




| :
So- ------------ 7---------------- -----




S-6 -. Depth of Closure





-12
-12


0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure A-32: Profiles for Monument R-39 in Palm Beach County.


















APPENDIX B
JID BEACH PROFILES FOR PALM BEACH COUNTY


Monument R-10
7.5 I I I I
S: --August



2.5-
5 ... .. ; .. : ... June 21







S-2.5-
Q ---------7---- ------------C----------


0 .Depth of C
I; -7.5
4)


1 5 L I i i i
0 200 400 600 800 1000 1200 1400 1600 1800
Distance from Monument (m)

Figure B-1: Profiles for Monument R-10 in Palm Beach County.








76



Monument R-11
7.5 I I I I
August 2001

5 ---June 2002
SOctober 2002

2.5



0 ------- -------------------------------------- 7-------




2 Depth of Closure
-7.5

-10

-12.5 .


-1 5 I I I I I I
0 200 400 600 800 1000 1200 1400 1600 1800
Distance from Monument (m)

Figure B-2: Profiles for Monument R-1 1 in Palm Beach County.


Monument R-12
7 .5 I I I I I I
August 2001
---June 2002
....... October 2002









"1 -7.5 ............... ..........................October
2.5










S-10



S-12.5 -
-15








Figure B-3: Profiles for Monument R-12 in Palm Beach County.
Figure B-3: Profiles for Monument R-12 in Palm Beach County.












Monument R-13


800 1000
Distance from Monument (m)


Figure B-4: Profiles for Monument R-13 in Palm Beach County.


Monument R-14
7.5 ,


2.5 -





2.5


S7.-5 --

2 -7.5


0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure B-5: Profiles for Monument R-14 in Palm Beach County.


1800












Monument R-15


800 1000
Distance from Monument (m)


Figure B-6: Profiles for Monument R-15 in Palm Beach County.


Monument R-16
7.5 ,









-2.5
a ----tri >_------------------- --------^--




o A ------
"---5


-7.5


0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)

Figure B-7: Profiles for Monument R-16 in Palm Beach County.


1800








79



Monument R-17
7.5 ,I
[ -- May 1995
I -- May 1996
March 1997
.-August 2001
2.5 October 2002
April 2004
P0 --------------------------------------------------------






S""- Depth of Closure



-10
-4*

-125 -


-15 I I I I I
0 200 400 600 800 1000 1200 1400 1600 1800
Distance from Monument (m)

Figure B-8: Profiles for Monument R-17 in Palm Beach County.


Monument R-18
7 .5 I I I I I I
August 2001
---June 2002
5 ........ : ..... .... ........... ... .. ... ... ............... ........... June 2002
-. October 2002

2 .5 .. .... .





SDepth of Closure


S-5
-7.5-

-10 -


-12.5-


0 200 400 600 800 1000 1200 1400 1600 1800
Distance from Monument (m)

Figure B-9: Profiles for Monument R-18 in Palm Beach County.








80



Monument R-19
7.5 I I I I I I
August 2001
5 ---June 2002
...... October 2002










0 -
-2.5
.j ------ ---------------------------------------------

-15 ... I .. ........

Figure B-10: Profiles for Monument R-19 in Palm Beachep of Closure















-12.5
0 200 400 600 800 1000 1200 1400 1600 1800
Distance from Monument (m)

Figure B-10: Profiles for Monument R-19 in Palm Beach County.


Monument R-20
7.5 -
S -- August 2001
5 ...... .. : ......... .. : .. .. ....... .. .. ....... ........ .. .. ......... .. .. : .......... J u n e 2 0 0 2
........ -October 2002




p 0 -- ---- -------------- -------------------------






Depth of Closure
-7.5

-10


-12.5


-15 I
0 200 400 600 800 1000 1200 1400 1600 1800
Distance from Monument (m)

Figure B- 1: Profiles for Monument R-20 in Palm Beach County.








81




Monument R-21
7.5


5-





P 0 --- ---- --
S2.5



S----------------------
S.-2 .5 .. .. .. . .


*I -5-
0
- 7.5
4)


0 200 400 600 800 1000 1200 1400 1600
Distance from Monument (m)


Figure B-12: Profiles for Monument R-21 in Palm Beach County.














APPENDIX C
STORMS NEAR JUPITER INLET, FLORIDA

Table C-1 contains storms that occurred within a vicinity of approximately 150 km

of Jupiter Inlet between 1974 and 2004. The storm data was obtained from the National

Oceanic and Atmospheric Administration (NOAA) website. The shoreline and volume

changes that were calculated from the profile survey data and presented in Chapter 3

showed no effects of these storms because the dates in which the storms occurred did not

correspond with the dates in which the surveys were taken. If survey data were available

from the same years that the storms occurred, then it is possible that the effects of the

storms would be noticeable in the shoreline and volume change calculations.

Table C-1: Storms occurring within 150 km of Jupiter Inlet
Year Storm Name Storm Classification
1976 Dottie Tropical Storm
1979 David Hurricane
1983 Barry Hurricane
1984 Diana Hurricane
1984 Isidore Tropical Storm
1985 Bob Tropical Storm
1987 Floyd Hurricane
1988 Chris Tropical Storm
1988 Keith Tropical Storm
1991 Ana Tropical Storm
1992 Andrew Hurricane
1994 Gordon Hurricane
1995 Erin Hurricane
1995 Jerry Tropical Storm
1999 Harvey Tropical Storm
1999 Irene Hurricane
2004 Charley Hurricane
2004 Frances Hurricane
2004 Jeanne Hurricane















LIST OF REFERENCES


ALBADA, E., and CRAIG, K., 2006. Jupiter/Carlin shore protection project, Palm
Beach County, Florida 24 month monitoring report. Report for Palm Beach
County, Florida.

AUBREY, D.G., and DEKIMPE, N.M., 1988. Performance of beach nourishment at
Jupiter Island, Florida. Proceedings of the Beach Preservation Technology '88
Conference, L.S. Tait (ed.), Florida Shore and Beach Preservation Association,
Tallahassee, Florida, 409-420.

BUCKINGHAM, W. T., 1984. Coastal engineering investigation at Jupiter Inlet, Florida.
MS thesis. Coastal and Oceanographic Engineering Department, University of
Florida, Gainesville, Florida, 228p.

DEAN, R.G., 2005. Analysis of the effect of Sebastian Inlet on adjacent beach systems
using DEP surveys and coastal engineering principles. UFL/COEL-2005/003, Civil
and Coastal Engineering Department, University of Florida, Gainesville, Florida,
22p, plus appendices.

DEAN, R.G., and DALRYMPLE, R.A., 2002. Coastal Processes n /ih Engineering
Applications. Cambridge: Cambridge University Press.

DOMBROWSKI, M.R., 1994. Ebb tidal delta evolution and navigability in the vicinity
of coastal inlets. MS thesis. Coastal and Oceanographic Engineering Department,
University of Florida, Gainesville, Florida, 95p.

DOMBROWSKI, M.R., and MEHTA, A.J., 1993. Inlets and management practices:
southeast coast of Florida. Journal of Coastal Research, Special Issuel8, A.J.
Mehta (ed.), The Coastal Education and Research Foundation, 29-57.

GRELLA, M. J., 1993. Development of management policy at Jupiter Inlet, Florida: An
integration of technical analyses and policy constraints. Journal of Coastal
Research, Special Issue 18, A.J. Mehta (ed.), The Coastal Education and Research
Foundation, 239-256.

MEHTA, A.J.; GRELLA, M.J.; GANJU, N.K.; and PARAMYGIN, V.A., 2005.
Sediment management in estuaries: The Loxahatchee, Florida. Port and Coastal
Engineering, P. Bruun (ed.), The Coastal Education and Research Foundation,
West Palm Beach, Florida, 276-303.









PATRA, R.R., 2003. Sediment management in low energy estuaries: The Loxahatchee,
Florida. MS thesis. Civil and Coastal Engineering Department, University of
Florida, Gainesville, Florida, 116p.

PATRA, R.R., and MEHTA, A.J., 2004. Sedimentation issues in low-energy estuaries:
The Loxahatchee, Florida. UFL/COEL-2004/002, Civil and Coastal Engineering
Department, University of Florida, Gainesville, Florida, 40p.

RODRIGUEZ, E., and DEAN, R.G., 2005. Sediment budget analysis and management
strategy for Fort Pierce Inlet, Florida. UFL/COEL-2005/004, Civil and Coastal
Engineering Department, University of Florida, Gainesville, Florida, 103p, plus
appendices.

STAUBLE, D.K., 1993. An overview of southeast Florida inlet morphodynamics.
Journal of Coastal Research, Special Issue 18, A.J. Mehta (ed.), The Coastal
Education and Research Foundation, 1-27.

TABAR, J.R.; UTKU, M.; and SPURGEON, J.R., 2002. Town of Jupiter Island, Florida,
beach renourishment project performance evaluation. Proceedings 2002 National
Conference on Beach Preservation Technology, L. Tait (ed.), Florida Shore and
Beach Preservation Association, Tallahassee, Florida, 71-89.















BIOGRAPHICAL SKETCH

Kristen Marie Odroniec was born in Michigan in 1982 to Karen and Stan Odroniec.

When she was ten years old, the author's family moved to Florida, where she developed

an interest in the nearby beach and coastline. Upon completion of high school in 2000,

she moved to Gainesville, where she pursued a Bachelor of Science degree in civil

engineering at the University of Florida. Kristen graduated in December 2004, and she

entered the Coastal and Oceanographic Engineering Program at the University of Florida

in January of 2005. After obtaining her Master of Science degree in coastal engineering,

Kristen plans to join the industry as a coastal engineer.