annual report for 1999 - stockton...

2013 ANNUAL REPORT ON THE CONDITION OF THE MUNICIPAL BEACHES FOR

THE BOROUGH OF STONE HARBOR, CAPE MAY COUNTY, NEW JERSEY

View along the beach looking south from 103rd Street on October 28, 2013. The US Army Corps of Engineers (USACE) completed a maintenance nourishment project on the Borough beaches in July 2013 to restore eroded beaches during Hurricane Sandy. Beaches and dunes were restored to the original federal project design template. Subsequent natural alterations eroded the beachface slope and project beach berm producing temporary berm top ponding shown in this photo. PREPARED FOR: THE BOROUGH OF STONE HARBOR 9508 SECOND AVENUE STONE HARBOR, NJ 08247 PREPARED BY: THE RICHARD STOCKTON COASTAL RESEARCH CENTER 30 WILSON AVENUE PORT REPUBLIC, NEW JERSEY 08241

April 30, 2014

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Contents

Introduction ................................................................................................................................................................1

Beach Monitoring Program Methodology .................................................................................................................2

Stone Harbor Engineered Beach Performance ..........................................................................................................2

Table 1 - Stone Harbor Fall 2013 Semi-Annual Changes ...........................................................................................3

Table 2 - Stone Harbor 2013 Annual Changes ............................................................................................................4

Table 3 - 2013 Post USACE Maintenance Nourishment Project.................................................................................5

Individual Site Descriptions ........................................................................................................................................6

Photoplates (1a-8d) Beach Conditions .......................................................................................................................8

Figures (1a-8b) Comparison Plots…………………………………………………………………………………………………………………………9

Summary .................................................................................................................................................................. 38

Conclusion/Recommendations ............................................................................................................................... 39

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Introduction: This annual report presents the status of the beaches within the Borough of Stone Harbor for 2013 and recovery since Hurricane Sandy eroded 380,800 cubic yards of sand from the municipal beaches during the storm. Following Sandy the focus in 2013 was on restoration of the Jersey shore, its beaches and dunes. Local, State and Federal efforts have helped shore communities devastated by the storm recover and rebuild. In Stone Harbor those efforts included a major beach nourishment project to restore the federal project beaches to the full design template. Erosion of the project beach continued following construction. Sand was stripped from the beachface and beach berm carried cross-shore to the offshore slope where it accumulated as a large shore parallel sand bar that continued well offshore beyond the survey limits. In 2013 the US Army Corps of Engineers (USACE) in a maintenance beach nourishment project placed 674,224 cubic yards (cy) (USACE reported pay volume) of sand on the beaches between about 80th Street and 123rd Street to repair erosional damage to the dunes and beach. The USACE was authorized to conduct an emergency nourishment project and to restore project dunes and beaches to the full design template. This project was eligible for Flood Control and Coastal Emergency funds under Public Law 84-99 and in response to P.L. 113-2 Disaster Relief Appropriations Act the project beach was eligible for restoration to design template. When the project was completed the beach width and elevation had been restored to original pre-storm project conditions or the design template. To conduct the work a contract awarded in September 2012 to repair Hurricane Irene was modified under this authorization to complete repairs for Hurricane Irene and Hurricane Sandy restoration concurrently. Norfolk Dredging Co. was contracted to place approximately 700,000 cubic yards of sand on the beach and dune, construction of the project started in spring 2013 and was completed during the summer of 2013. The Richard Stockton College of New Jersey Coastal Research Center (CRC) completed the fall review of the municipal beaches, survey #41 on October 28, 2013 following what was a relatively mild weather pattern this year. Semi-annual shoreline and sand volume changes were calculated between survey #40, and the most recent study. An additional post-construction survey was conducted following the USACE 2013 nourishment project completed August 6, 2013 to quantify shoreline and sand volume changes due to the project at the eight monitoring sites. Enclosed with this annual report are comparison profile plots that show beach configuration changes between the last four studies at the eight monitoring sites that include the 2013 USACE project to just before Hurricane Sandy. 2013 Weather Events Winter storm Saturn tracked up the east coast for several days from March 4 - 7, 2013. The storm dropped several feet of snow in West Virginia and Virginia caused coastal flooding as far south as North Carolina and brought more snow, high winds and dangerous coastal flooding to the Northeast and New England. On March 5, 2013 the winter northeaster began to move north along the New Jersey coast and caused significant beach erosion In Cape May County and along the Stone Harbor engineered beaches. Storm waves generated during Saturn over washed and flattened the beach berm reduced the beach width and elevation and scoured the nearshore seafloor. Erosion suffered during Saturn was repaired during the USACE project completed by summer 2013. On and around October 10, 2013 72 hours of 30 plus knot onshore winds generated storm waves that cut into the recently completed project beach. Waves generated during this event eroded the beachface, flattened the berm and scoured the nearshore. Sand was transferred cross-shore well offshore forming

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massive shore-parallel sand bar system that extended seaward beyond the survey limits. This was the initial event in a series of storms to impact the Jersey shoreline during the winter storm season 2013-2014. As calmer weather returns in late spring/summer 2014 and natural beach building occurs some of this sand may move back onshore. Beach Monitoring Program Methodology The CRC established the Borough’s beach monitoring program in June of 1996 to address the shoreline changes along the 13,077 feet of municipal oceanfront beaches. Eight permanent beach profile-monitoring sites were established to gather data on a quarterly basis. Each profile starts at a fixed reference position behind the dunes, crosses the dunes, beach and extends over 600 feet into the water, ending at a depth of 12-16 feet. Each of the groin compartments or cells along the Borough beachfront contains one profile line. Work continued on a semi-annual monitoring schedule. The following list describes the selected sites and locations: ♦ SH-82 82nd Street Border with Avalon – 84th St. groin ♦ SH-90 90th Street 84th St. groin – 92nd St. groin ♦ SH-95 95th Street 92nd St. groin – 98th St. groin ♦ SH-103 103rd Street 98th St. groin – 106th St. groin ♦ SH-108 108th Street 106th St. groin – 111th St. groin ♦ SH-112 112th Street (paper street) 111th St. groin – 114th St. groin ♦ SH-116 116th Street 114th St. groin – 122nd St. groin ♦ SH-123 123rd Street (paper street) 122nd St. groin – terminal groin Stone Harbor Engineered Beach Performance When Sandy made landfall in October the beaches and dunes were again damaged and the gains since Irene eliminated. The beaches were severely eroded and dunes cut back but the overall dune stability was maintained providing ample storm protection for oceanfront properties once again. Damage to beach access crossovers, ramps and pavilions was extensive but the public infrastructure inland was largely protected from storm waves. The USACE engineered beach had sustained two significant storm events in back to back years but maintained its storm protection value to the community preventing major flooding from storm wave over wash and dune breaches. In regions of north Jersey where beach and dune maintenance were lacking communities were not as fortunate. Many of these communities suffered not only major beach erosion but damage and destruction of both private property and public infrastructure. Here, in response to the erosion the USACE performed maintenance nourishment in 2013 to restore the severely eroded beaches to the full original project design template as part of its long term commitment to maintain Stone Harbor’s storm damage reduction project beach. Following completion the project beach configurations have readjusted and eroded at an accelerated rate. By late October 2013, a third to two-thirds of the project berm width had eroded with sand transferred offshore or swept south on longshore currents. As favorable weather and wave climate conditions develop for natural beach buildings processes to begin in spring/summer 2014 some of the sand transferred offshore should naturally move landward and restore some of these onshore losses. Table 1 below displays the change in shoreline positions and sand volume changes for the previous six months. Shoreline changes are calculated by comparing the zero datum positions in the current survey to the previous survey. Sand volume changes are calculated for each individual profile site by computing the cut and fill cell changes in the profile with the previous survey. These values are

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expressed in cubic yards (cy) of sand per linear foot of beachfront (yds3/ft) the total beach volume change is calculated using this value. The distance (cell width) between groins along the beachfront of Stone Harbor was measured between the centerlines of adjacent groins. Each cell’s net sand volume change is computed by multiplying each cross section volume change by its corresponding groin cell width.

Table 1

Stone Harbor Fall 2013 Semi-Annual Shoreline and Profile Sand Volume Changes August 6, 2013 (postfill) to October 28, 2013

Profile Shoreline Volume Cell Cell Volume Number Change Change Distance Change

(feet) (yds3/ft) (feet) (yds3)

SH-82 -72 -34.04 1,381 -47,009

SH-90 -22 4.51 2,240 10,102

SH-95 -30 -2.78 1,680 -4,670

SH-103 -2 1.09 2,208 2,407

SH-108 -59 -11.79 1,433 -16,895

SH-112 -6 10.17 804 8,177

SH-116 46 28.16 2,273 64,008

SH-123 -58 -36.30 1,058 -38,405

Total Volume Change = -22,287

The total net sand volume change over late summer and early fall of 2013 was a very modest loss of 22,287cy of sand from across the entire Stone Harbor oceanfront including the dunes, beaches and offshore seafloor. At most of the sites with the exception of 116th Street the shoreline position retreated. Shoreline changes were highly variable and ranged from a moderate advance of 46 feet at 116th Street to 72 feet of retreat at 82nd Street. In addition to the shoreline position changes the project beach berm widths eroded landward up to 150 feet. Again each site showed onshore sand volume losses except at 116th Street where there was a modest gain (3.77yds3/ft.). Onshore losses ranged from -13.90 to -33.68 yds3/ft. of sand from above the zero datum elevation. The project beaches onshore (above the zero datum) loss a net 240,687 cubic yards of sand. Offshore the sand volume changes were all positive as sand was swept cross-shore from the beach to the seafloor, the net effect offset much of the onshore losses to reduce the net sand volume loss for the study interval. Table 2 below displays the shoreline position and sand volume changes at each of the eight sites for the 2013 monitoring year, as compared to conditions just prior to Hurricane Sandy. Shoreline changes are calculated by comparing the zero datum positions in the current survey to the previous year’s October

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24th survey. Sand volume changes are calculated for each individual profile site by computing the cut and fill cell changes in the profile with the previous survey. These values are expressed in cubic yards of sand per linear foot of beachfront (yds3/ft) the total beach volume change is calculated using this value. The distance (cell width) between groins along the beachfront of Stone Harbor was measured between the centerlines of adjacent groins. Each cell’s net sand volume change is computed by multiplying each cross section volume change by its corresponding groin cell width.

Table 2

Stone Harbor 2013 Annual Changes Semi-Annual Survey Study Area

Shoreline and Profile Sand Volume Changes October 24, 2012 to October 28, 2013



SH-82 -35 -35.05 1,381 -48,404

SH-90 9 31.64 2,240 70,874

SH-95 -5 5.86 1,680 9,845

SH-103 -8 18.74 2,208 41,378

SH-108 -55 3.49 1,433 5,001

SH-112 -10 40.47 804 32,538

SH-116 -4 30.13 2,273 68,485

SH-123 -27 5.28 1,058 5,586 13,077

Total Volume Change = 185,303

Along the Borough’s shoreline the net annual sand volume change was a gain of 185,303cy, from just prior to the arrival of Sandy on October 24, 2012 to one year later on October 28, 2013. The USACE project added 674,224cy of sand. Hurricane Irene, the October 2011 northeaster and Sandy combined to remove 120% of the sand placed in 2011 during that USACE maintenance project, a total of nearly 702,000 cubic yards of sand eroded from the beaches in less than a year and a half. An additional 108,121cy of sand was lost during Saturn and the October 10, 2013 storm (wind) event. Unfortunately, onshore losses to the 2013 USACE project were extensive as a third to two thirds of the project berm width was eroded but sand was transferred offshore offsetting some of the onshore volume losses. For the year 295,271 cubic yards of sand accumulated offshore (below zero datum). Only the site at 82nd Street suffered a net sand volume loss for the year, a substantial loss of 35.05 yds3/ft. of sand. In contrast only one site 90th street showed a net shoreline position advance for the year. Onshore project beach losses during the fall of 2013 were between -13.90 to -33.68 yds3/ft. of sand only 116th street showed a modest net sand volume gain (3.77yds3/ft.) onshore in 2013.

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Table 3 below displays the changes in shoreline positions and sand volume changes for the entire study area as a result of the 2013 USACE project. Shoreline changes are calculated by comparing the zero datum positions in the pre-construction survey #39 to post construction survey #40. Sand volume changes are calculated for each individual profile site by computing the cut and fill cell changes in the profile with the previous survey. These values are expressed in cubic yards of sand per linear foot of beachfront (yds3/ft.) the total beach volume change is calculated using this value. The distance (cell width) between groins along the beachfront of Stone Harbor was measured between the centerlines of adjacent groins. Each cell’s net sand volume change is computed by multiplying each cross section volume change by its corresponding groin cell width.

Table 3

Stone Harbor Semi-Annual Survey 2013 Post USACE Maintenance Nourishment Project

Shoreline and Sand Volume Changes May 14, 2013 to August 6, 2013



SH-82 106 65.05 1,381 89,834

SH-90 71 61.10 2,240 136,864

SH-95 135 79.14 1,680 132,955

SH-103 95 65.84 2,208 145,375

SH-108 93 69.33 1,433 99,350

SH-112 69 54.95 804 44,180

SH-116 13 17.57 2,273 39,937

SH-123 148 25.38 1,058 26,852

Total Volume Change = 715,346

In table 3 using just the eight municipal monitoring profiles the Coastal Research Center studies showed from May 14 to August 6, 2013 the Borough’s 13,077 feet of oceanfront shoreline gained 715,346 cubic yards (cy) of sand mostly derived from the 2013 USACE emergency beach maintenance project. Losses caused by Hurricanes Irene, October 2011 nor’easter, super storm Sandy and winter storm Saturn were addressed by this USACE project that restored the beach and dune to the full design template. The majority of sand was placed from the Avalon boarder to 112th Street. Fill volumes tapered to the south as net sand transport along the Borough’s shoreline is to the south and required less sand to restore the template. The 715,346 cy (CRC) of sand placed across 13,077 feet of the Borough’s oceanfront shoreline during the 2013 USACE project averages to a gain of 54.70 yds3/ft. Using the eight municipal

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sites confirms the USACE pay volume of 674,224 cy of sand the 715,346 cy is within agreement of less than 6% variation in the municipalities favor. In 2012 the Borough lost 380,859 cubic yards of sand during “Superstorm Sandy” from just the dune and beach. This represents nearly 65% of the 580,000 cubic yards of sand placed during the 2011 USACE project by Great Lakes Dredge and Dock. Combined with the losses since construction (55%) the total sand volume placed was completely removed by two hurricanes and a modest nor’easter in a little over one year. Hurricane Irene, the October 2011 northeaster and Sandy combined removed 120% of the sand placed in 2011, nearly 702,000 cubic yards of sand from the beach and dunes. Much of this sand moved south to the Hereford Inlet shoreline where the South Pointe beaches have continued to expand south into the inlet by another 500 feet just this past year. This southern spit at the south end of Stone Harbor continues to grow and now extends south over a mile (5,555 feet) from the terminal groin located several hundred feet south of the last development and parking lot at 123rd Street. Changes in the ebb-tidal shoals and shorelines of Hereford Inlet are being tracked by the CRC for the Bureau of Coastal Engineering. Individual Site Descriptions This section describes the changes documented at each of the cross section locations. In general, for 2013, the summer season was one of significant sand accumulation recovering much of the losses suffered from previous storm events. The USACE completed a project in 2013 to restore storm damage from Sandy along the engineered beach. Winter storm Saturn impacted the shoreline in March 2013 following Sandy and further eroded the beach. Losses to the engineered beach were significant but the dune system remained largely intact with minor scarps at a few locations where the beaches were narrow. Natural sand recovery in early spring restored much of the damage caused by Saturn while the USACE project restored the beaches to the original federal design template. Unfortunately, an early event in October with sustained onshore winds lasting 72 hours eroded much of the gains by the final survey for 2013 near the end of October. SH-82, located at 82nd street along 1st Avenue seaward of the 82nd Street recreation area. The profile line was set approximately midway between the Avalon border and the groin at 84th Street. This site was included in the Borough’s monitoring program to represent typical beach conditions on the Borough’s only stretch of beach without a groin to the north. The beach is located about 800 feet south of the Avalon border and the USACE federal project taper. This site consists of 200 feet of primary dune width seaward of the asphalt promenade set on top of the revetment from its landward offset at 83rd Street to 80th Street. Hurricane Sandy made landfall on October 29th causing significant erosion of the beach and seaward dune slope back to the crest. Following the storm an 8 to10-foot high scarp was left in the dune and the beach elevation was 2 to 4 feet lower compared to the October 23rd survey. Sandy removed 31.91yds3/ft. of sand from the dune and beach that resulted in a shoreline retreat of 92 feet. Some of the eroded sand was carried offshore and deposited as a shore parallel bar that could move back onshore when weather and seas conditions are favorable. Winter storm Saturn brought strong onshore winds that generated storm waves while the surge caused higher tides. The combined effects further flattened and eroded the beach and nearshore but the width of the post Sandy beach was sufficient to protect the dune system from further damages. In spring 2013

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the USACE maintenance project commenced and worked south to north to repair storm damages the project reached this region by late July. By August the project beach berm extended 220 feet seaward of the dune toe. No sand was placed directly on the dune during the project as the post Sandy conditions exceeded the design configuration. The project added 65.05 yds3/ft. of sand to the profile, advanced the shoreline position 106 feet and raised the beach elevation to 7.5 feet NAVD 88. Unfortunately, within a few months nearly two thirds of the project berm had eroded and the nearshore scoured with much of the erosion occurring during an October event with sustained onshore winds above 30 knots that persisted for 72 hours. The site lost 34.04 yds3/ft. of sand and 140 feet of berm width while the shoreline position retreated 72 feet. Some sand was transferred cross-shore to the seafloor but most was carried outside the survey limits or swept downdrift on longshore currents. Comparing the October 23, 2012 survey taken days before Hurricane Sandy arrived with the October 25, 2013 survey shows the beach was still 35.05yds3/ft. of sand below the pre-sandy sand volume and the shoreline position 35 feet landward despite the USACE project. Site SH-82 – 82nd Street (Photoplate 1a-1d)

Photoplate 1a - Photo was taken March 14, 2013 looking south along the dune toe from 82nd Street. The beach is flatter following winter storm Saturn but along the dune toe aeolian sand accumulated and reduced the steepness of the Sandy storm scarp.

Photoplate 1b - Photo was taken May 14, 2013 again looking south along the dune toe from 82nd Street. Dune fence was installed to capture aeolian sand but the beach remained relatively narrow prior to the 2013 USACE project.

Photoplate 1c - Photo was taken August 6, 2013 looking south along the dune toe from 82nd Street. The beach is wider following completion of the 2013 USACE restoration efforts. No sand was added to the dune system but sand continued to naturally accumulate along the fence installed at the dune toe.

Photoplate 1d - Photo was taken October 25, 2013 looking south along the dune toe from 82nd Street. Following the summer season an early October onshore wind event generated waves that eroded the beachface but moved aeolian sand to the dune fence burying half the fence with up to 2 feet of sand.

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Figure 1a – The quarterly comparison plots shows the beach and dune erosion following Hurricane Sandy and winter storm Saturn. The seaward dune slope was cut 40 feet landward into a steep scarp and the beach flattened and reduced in both width and elevation. The August survey shows the USACE 2013 project beach provided about 250 feet of additional beach berm width and raised the elevation of the beach by up to 6 feet to elevation 8 feet NAVD88. The nearshore also gained sand advancing the shoreline position seaward approximately 100 feet.

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Figure 1b – The annual comparison plots show the beach and dune have not fully recovered following Hurricane Sandy to its pre-storm configuration despite the USACE 2013 project. Waves generated by the early October 2013 sustained onshore winds eroded nearly two thirds of the project beach berm. Losses persisted nearshore with an indication of an offshore bar development near the profile limits where 12.48 yds3/ft. of sand accumulated. This feature likely continued well beyond the survey limits indicating sand was transferred from the beach and nearshore to l offshore. The net volume change for the year was a loss of 35.05 yds3/ft. of sand and shoreline position landward retreat of 35 feet.

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SH-90, located at 90th Street, the site was originally established in 1986 as a survey site for the New Jersey Beach Profile Network (NJBPN). The profile line was set north of the public beach access path to provide a typical cross-sectional representation of the dune and beach within this groin cell. The dune system consists of two ridges approximately 150 feet wide extending from the street end revetment to the seaward dune toe. Hurricane Sandy’s landfall along Stone Harbor’s beaches although less intense than in Ocean and Monmouth Counties caused considerable beach and dune erosion. Resulting shoreline retreat from Sandy was 34 feet as 23.45 yds3/ft. of sand was stripped from the dune and beach. The beach elevation was reduced by 1 to 4-feet in elevation and the developing fore dune was obliterated leaving a modest dune scarp along the seaward slope. Winter storm Saturn’s combined effects further flattened and eroded the beach and nearshore. The width of the post Sandy beach was sufficient to protect the dune system from further damages. By August the 2013 USACE project had restored this beach to its original design template. The project added 61.10 yds3/ft. of sand to the system, advanced the shoreline position seaward 71 feet and raised the beach berm elevation to 7.5 feet NAVD88 for 200 feet seaward of the dune toe. The nearshore slope elevation also increased up to 3 feet as sand moved offshore during the project. No sand was placed directly on the dune during the project as the post Sandy conditions exceeded the design configuration. A 12-foot deep trough nearly 150 feet wide separated the project beach from an offshore sand bar deposited during the previous storm events. Unfortunately, within a few months nearly a third of the project berm had eroded and the nearshore scoured with much of the erosion occurring during an October event with sustained onshore winds above 30 knots that persisted for 72 hours. Sand was transferred cross-shore to the seafloor and additional sand was carried downdrift to this location and accumulated offshore offsetting onshore losses. The net result was a modest volume gain of 4.51yds3/ft. of sand despite the loss of about 75 feet of project berm width and 22 feet of shoreline retreat. Comparing the October 23, 2012 survey taken days before Hurricane Sandy arrived with the October 25, 2013 survey shows the beach was 31.64yds3/ft. of sand above the pre-sandy sand volume and the shoreline position 9 feet seaward following the 2013 USACE project. Although the beach and nearshore in 2012 and 2013 were similar in configuration the accumulation of sand offshore during fall 2013 resulted in the net sand volume gain.

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Site SH-90 – 90th Street (Photoplate 2a-2d)

Photoplate 2a - Photo was taken March 14, 2013 looking south along the dune toe from 90th Street. The beach is relatively narrow and flattened by Hurricane Sandy and winter storm Saturn. A modest dune scarp is visible with modest aeolian accumulation.

Photoplate 2b - Photo was taken May 14, 2013 looking south along the newly installed row of dune fence from 90th Street. Aeolian sand had begun to accumulate around the base of the fence that partially restored the modest foredune eroded during Sandy.

Photoplate 2c - Photo was taken August 6, 2013 looking south along the dune toe from 90th Street. The 2013 USACE beach maintenance project restored the beach width and elevation to the original design template. No sand was added to the dune at this location.

Photoplate 2d - Photo was taken October 25, 2013 looking south along the dune toe from 90th Street. Following the summer season an early October onshore wind event generated waves that eroded about a third of the project beach berm width.

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Figure 2a – The quarterly comparison plots show significant beach and modest dune erosion following Hurricane Sandy and winter storm Saturn. The beach was flattened and lowered in elevation and the beach berm crest pushed landward nearly 100 feet. Foredune development at the seaward toe was cut back to the primary seaward dune slope. The August survey shows the USACE 2013 project beach provided about 200 feet of additional beach berm width and raised the elevation of the beach by up to 5 feet to elevation 7.5 feet NAVD88. The nearshore also gained sand advancing the shoreline position seaward approximately 60 feet. By October 25th the project beach berm had eroded approximately 60 feet and the nearshore was scoured following 72 hrs. of strong onshore winds and waves. Much of the sand was transferred cross-shore that filled the deep trough present in August 2013 limiting the net sand volume change.

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Figure 2b – The annual comparison plot shows the beach and dune had nearly recovered following Hurricane Sandy to its pre-storm configuration after the USACE 2013 project. Waves generated by the early October 2013 sustained onshore winds eroded nearly a third of the project beach berm and scoured the nearshore. Much of the sand was transferred offshore where 50.65 yds3/ft. of sand accumulated forming a new shore parallel bar that extended beyond the profile limits. The net volume change for the year was a gain of 31.64 yds3/ft. of sand that accumulated offshore while the shoreline position and beach berm width remained relatively stable. One year following Sandy this site mimics the pre-storm conditions following the USACE 2013 maintenance project.

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SH-95, the 95th Street site was established along the north side of 95th Street and the beach access path. The profile line crosses the municipal parking lot, a wooden bulkhead, access ramp and dune located just north of the municipal beach observation platform. The dune system is essentially a single ridge that extends seaward 140 feet from the street end revetment to the seaward dune toe with a crest elevation of 15 feet NAVD88. Sandy caused significant erosion at 95th Street lowering the beach elevation up to 4 feet destroying the fore dune and causing the shoreline position to retreat 75 feet. The onshore storm loss was 28.34 yds3/ft. of sand removed from the dune and beach volume with a 4 to 6-foot scarp in the seaward dune face. A developing foredune ridge was completely eliminated. Winter storm Saturn’s combined effects further flattened and eroded the beach and nearshore. The narrow width of the post Sandy beach allowed the storm wave run up to reach the seaward dune toe that cut a minor scarp at the toe. In spring 2013 the USACE maintenance project commenced and worked south to north and reached this location by summer. By the August post construction survey the project restored this beach to its original design template. The project added 79.14 yds3/ft. of sand to the system, advanced the shoreline position seaward 135 feet and raised the beach berm elevation to 7.5 feet NAVD88 220 feet seaward of the dune toe. The fill project also raised the nearshore slope elevation up to 3 feet as the beach pushed seaward and sand moved offshore during the project. No sand was placed directly on the dune during the project as the post Sandy conditions exceeded the design configuration. A 13-foot deep trough nearly 150 feet wide separated the project beach from an offshore sand bar deposited during the earlier storm events. Unfortunately, within a few months nearly half of the project berm had eroded and the nearshore scoured with much of the erosion occurring during an October event with sustained onshore winds above 30 knots that persisted for 72 hours. Sand was transferred cross-shore to the offshore seafloor partially offsetting onshore losses. The net result was a modest volume loss of 2.78 yds3/ft. of sand despite the loss of about 100 feet of project berm width and 30 feet of shoreline retreat. Comparing the October 23, 2012 survey taken days before Hurricane Sandy arrived with the October 25, 2013 survey shows the beach volume increased a modest 5.86 yds3/ft. of sand above the pre-sandy sand volume while the shoreline position retreated slightly 5 feet landward following the 2013 USACE project. Although the beach and nearshore in 2012 and 2013 were similar in configuration the accumulation of sand offshore during fall 2013 resulted in the modest net sand volume gain.

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Photoplate 3a - Photo was taken March 14, 2013 looking south along the dune toe from 95th Street. The beach is narrow and flattened by Hurricane Sandy and winter storm Saturn. Some aeolian sand has accumulated along the dune toe and the angle of the dune scarp cut into the seaward slope during Sandy reduced through slumping.

Photoplate 3b - Photo was taken May 14, 2013 looking south along the dune toe from 95th Street. The beach remained narrow but the elevation increased as sand started to move onshore. Wind-blown sand accumulated on the seaward dune slope as a thin veneer that reduced the steep scarp and restored a gentler slope.

Photoplate 3c - Photo was taken August 6, 2013 looking south along the dune toe from 95th Street. The 2013 USACE beach maintenance project restored the beach width and elevation to the original design template. A row of dune fence was installed but no sand was added directly to the dune during the project.

Photoplate 3d - Photo was taken October 25, 2013 looking south along the dune toe from 95th Street. Following the summer season an early October onshore wind event generated waves that eroded about half of the project beach berm width. Wind-blown sand had started to accumulate around the recently installed fence.

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Figure 3a – The quarterly comparison plots show significant beach and modest dune erosion following Hurricane Sandy and winter storm Saturn. The beach berm was flattened and lowered in elevation. A foredune that had developed at the seaward toe was completely eroded leaving a steep seaward slope. The August survey shows the USACE 2013 project beach provided about 200 feet of additional beach berm width and raised the elevation of the beach by up to 6 feet to elevation 7.5 feet NAVD88. The nearshore also gained sand during the project that resulted in a seaward advance of the shoreline position approximately 120 feet. By October 25th the project beach berm had eroded approximately 100 feet and the nearshore was scoured following 72 hours of strong onshore winds and waves. Much of the sand was transferred cross-shore filled the offshore trough and limited the net sand volume change.

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Figure 3b – The annual comparison plot shows the beach and dune had nearly recovered following Hurricane Sandy to its pre-storm configuration after the USACE 2013 project. Waves generated by the early October 2013 sustained onshore winds eroded nearly a half of the project beach berm and scoured the nearshore. Much of the sand was transferred offshore where 33.14 yds3/ft. of sand accumulated forming a new shore parallel bar that extended seaward beyond the profile limit. The net volume change for the year was a modest gain of 5.86 yds3/ft. of sand that accumulated offshore while the shoreline position remained relatively stable. One year following Sandy the foredune ridge has not re-developed nor was any sand added to the dune during the USACE recent project. Wave scour cut into the project beach berm steepened the beacface slope and scoured a deep trough nearshore compared to the pre-storm conditions and following the USACE 2013 maintenance project.

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SH-103, the 103rd Street site was established for the Borough’s beach monitoring program at the seaward end of 103rd Street along the north sidewalk. When the site was originally established in 1996, the profile crossed the bulkhead and dropped to the rock revetment at the toe of the bulkhead. An extremely narrow beach just seaward of the rocks provided limited recreational area for beach patrons. Storm waves and surge would overtop the revetment and cause local flooding. This beach continued to erode until by 1998 no dry beach existed seaward of the rock revetment. Sand was placed here during the 1998 municipal beach fill re-establishing a dry beach berm and dune ridge. In 2003 the initial Federal project enhanced the width of both the dune and beach. Several subsequent projects have been required to provide periodic beach maintenance that included the 2009 state/municipal project and spring/summer 2011 federal project. Five severe storms that included nor’easters on November 2009, March 2010 and December 2010 plus Hurricanes Irene 2011 and Sandy 2012 have had a major impact on the Stone Harbor beaches all within 4 years with each resulting in a Presidential Disaster Declaration. Hurricane Sandy made direct landfall near Atlantic City its storm surge and waves dramatically eroded the beach and dune. As a result of the storm erosion the shoreline position retreated 90 feet and the beach elevation was lowered 4 feet across most of the remaining beach. The dune was cut back about 40 feet at the toe eliminating the foredune feature and leaving a 5 to 7-foot scarp below the seaward crest. Onshore Sandy removed 29.90yds3/ft. of sand from the dune and beach. Winter storm Saturn’s combined wave and surge effects further flattened and eroded the beach and nearshore. The narrow width of the post Sandy beach allowed the storm wave run up to reach the seaward dune toe that cut a moderate 2-4 foot scarp at the toe. The 2013 USACE maintenance project construction reached this location by summer. The August post construction survey showed the project had restored this beach to its original design template. The project placed 65.84 yds3/ft. of sand to the system, advanced the shoreline position seaward 95 feet and raised the beach berm elevation to 7.5 feet NAVD88 that extended seaward 140 feet seaward of the dune toe. The fill project also raised the nearshore slope elevation up to 3 feet as the beach pushed seaward and sand moved offshore during the project. Sand was placed directly on the seaward dune slope during the project to restore the pre-Sandy dune configuration. A 12-foot deep trough nearly 150 feet wide separated the project beach from an offshore sand bar deposited during the earlier storm events. The October 25 survey followed an early October event with sustained onshore winds above 30 knots that persisted for 72 hours. By the time of the survey nearly half of the project berm eroded and the nearshore scoured with much of the erosion likely occurring during this event. Sand was transferred cross-shore to the offshore seafloor offsetting onshore losses. The net result was an extremely modest volume of 1.09 yds3/ft. of sand essentially indicating a complete exchange of sand between onshore losses and offshore gains. Despite the loss of about 75 feet of project berm width the shoreline position only retreated 2 feet with development of a shallow platform and ridge along the shoreline. Comparing the October 23, 2012 survey taken days before Hurricane Sandy arrived with the October 25, 2013 survey shows the beach volume increased 18.74 yds3/ft. of sand above the pre-sandy sand volume while the shoreline position retreated slightly 8 feet landward. Despite the 2013 USACE project the beach and nearshore by October 25, 2013 was narrower and lower than the 2012 pre-Sandy configuration but the accumulation of sand offshore during 2013 offset these onshore losses and resulted in the net sand volume gain for the year. The offshore bar accumulation contained 115,478 cy of sand transferred cross-shore from the eroded beaches just within this cell.

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Site SH-103 – 103rd Street (Photoplate 4a-4d)

Photoplate 4a - Photo was taken March 14, 2013 looking south along the dune toe from 103rd Street. The beach is narrow and flattened by Hurricane Sandy and winter storm Saturn. A steep dune scarp near the dune toe remains likely cut during the most recent storm the abrupt vegetation line marks the post-Sandy dune scarp.

Photoplate 4b - Photo was taken May 14, 2013 looking south along the dune toe from 103rd Street. The beach remained narrow but the elevation increased as sand started to move onshore. Wind-blown sand accumulated on the seaward dune slope that reduced the steep scarp and restored a gentler uniform slope.

Photoplate 4c - Photo was taken August 6, 2013 looking south along the dune toe from 103rd Street. The 2013 USACE beach maintenance project restored the beach width and elevation to the original design template. A row of dune fence was installed with sand added directly during the project to restore the seaward dune slope here.

Photoplate 4d - Photo was taken October 25, 2013 looking south along the dune toe from 103rd Street. Following the summer season an early October onshore wind event generated waves that eroded about half of the project beach berm width. Wind-blown sand had started to accumulate around the recently installed fence.

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Figure 4a – The quarterly comparison plots show significant beach and modest dune erosion following Hurricane Sandy and winter storm Saturn. The beach berm was cut landward, flattened and lowered 4 feet in elevation. The seaward dune slope was cut landward 45 feet. By August the post-construction survey shows the USACE 2013 project beach provided about 180 feet of additional beach berm width and raised the elevation of the beach by up to 6 feet to elevation 7.5 feet NAVD88. Sand was also added to the seaward dune slope to restore to the original project design configuration. The nearshore also gained sand during the project that resulted in a seaward advance of the shoreline position approximately 100 feet. By October 25th the project beach berm had eroded approximately 75 feet and the nearshore was scoured following 72 hours of strong onshore winds and waves. Much of the sand was transferred cross-shore filled the offshore trough and limited the net sand volume change.

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Figure 4b – The annual comparison plot shows the beach and dune despite the USACE 2013 project failed to maintain its pre-storm configuration following Hurricane Sandy. Waves generated in early October 2013 by sustained onshore winds eroded nearly half of the project beach berm and scoured the nearshore. Much of the sand was transferred offshore where 52.34yds3/ft. of sand accumulated that raised the seafloor elevation by up to 3 feet. The sand transfer beyond the profile limits demonstrates the impact of cross-shore transport. The net volume change for the year was a moderate gain of 18.74 yds3/ft. of sand that accumulated offshore while the shoreline position remained relatively stable. One year following Sandy a modest foredune ridge had partially re-developed following sand placement during the USACE recent project. Wave scour cut into the project beach berm steepened the beacface slope and scoured a deep trough nearshore compared to the pre-storm conditions and following the USACE 2013 maintenance project.

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SH-108, is located at the end of 108th Street and was placed near the middle of this groin cell. The history here is similar to site SH-103. When the site was originally established in 1996, the profile crossed the bulkhead and dropped to the rock revetment at the toe of the bulkhead. An extremely narrow beach just seaward of the rocks provided limited recreational area for beach patrons. Exposure of the rocks accelerated the beach erosion as waves refracted off the hard structure and scoured the sandy beach. Larger storm waves and surge would overtop the revetment and cause local flooding. Sand was also placed here during the 1998 municipal beach fill re-establishing a dry beach berm and dune ridge. In 2003 the initial Federal project enhanced the width of both the dune and beach. Several severe storms have impacted the Stone Harbor beaches since 2009 including Hurricanes Irene in 2011 and Sandy in 2012. Storm erosion has required subsequent periodic beach maintenance that included the 2009 State/municipal project and 2011 federal project, the 2013 USACE project continued this trend restoring erosion caused by the two hurricanes. Sandy struck the New Jersey coast near Atlantic City on October 29, 2012. At 108th Street in Stone Harbor the surge and waves from Sandy slammed into the seaward dune slope removed the fore dune and cut up to 7-foot high scarps along the seaward dune crest. Beach elevations were lowered about 3 feet and the shoreline position retreated 83 feet. Despite the significant erosion the dune system again, as during Irene, retained sufficient volume and height to protect oceanfront properties. About four months following Sandy winter storm Saturn moved up the New Jersey coast March 5-6, 2013. The combined wave and surge effects further flattened and eroded the beach and scoured the nearshore. The narrow width of the post Sandy beach allowed the storm wave run up to reach the seaward dune toe and cut a moderate 2-4 foot scarp at the toe. The 2013 USACE maintenance project was finished in this region by June 12, 2013. The June post construction survey showed the project had restored this beach to its original design template. The project placed 69.33 yds3/ft. of sand into the system, advanced the shoreline position seaward 93 feet and raised the beach berm elevation to 7.5 feet NAVD88 that extended 180 feet seaward of the dune toe. The fill project also raised the nearshore slope elevation up to 3 feet as the beach pushed seaward and sand moved offshore during the project. Sand was placed directly on the seaward dune slope during the project to restore the pre-Sandy dune configuration. A 13-foot deep trough over 150 feet wide separated the project beach from an offshore sand bar deposited during the earlier storm events. The October 28 survey followed the early October event with sustained onshore winds above 30 knots that persisted for 72 hours. By October 28, 2013 nearly two-thirds of the project berm eroded (125 feet) and the nearshore scoured. Sand was transferred cross-shore to the offshore seafloor partially offsetting some of the onshore losses. The net result was a loss of 11.79 yds3/ft. of sand with a shoreline position retreat of 59 feet as the beachface slope and nearshore were scoured by the fall wave climate. Comparing the October 24, 2012 survey taken days before Hurricane Sandy arrived with the October 28, 2013 survey shows the beach volume increased a modest 3.49 yds3/ft. of sand above the pre-sandy sand volume while the shoreline position retreated 55 feet landward. Despite the 2013 USACE project the beach and nearshore by October 28, 2013 was narrower and lower than the 2012 pre-Sandy configuration. The accumulation of sand offshore during 2013 offset these onshore losses and resulted in the modest net sand volume gain for the year. The offshore bar accumulation consisted of 63,769 cy of sand transferred offshore within this cell.

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Photoplate 5a - Photo was taken March 14, 2013 looking north along the dune toe from 108th Street. The beach was extremely narrow and flattened by Hurricane Sandy and winter storm Saturn. A modest steep dune scarp near the dune toe was likely cut during the most recent storm while the abrupt vegetation line marks the post-Sandy dune scarp.

Photoplate 5b - Photo was taken May 13, 2013 looking north along the dune toe from 108th Street. The beach remained narrow but the elevation increased as sand started to move onshore, note difference in exposed pipeline in distance with photo 5a. Wind-blown sand accumulated on the seaward dune slope that restored a gentler uniform slope.

Photoplate 5c - Photo was taken June 12, 2013 looking north along the dune toe from 108th Street. The 2013 USACE beach maintenance project restored the beach width and elevation to the original design template. Sand was added directly to the dune during the project to restore the seaward dune slope but no fence had yet been installed.

Photoplate 5d - Photo was taken October 28, 2013 looking north along the dune toe from 108th Street. The early October 10, 2013 onshore wind event generated waves that eroded about two thirds of the 2013 USACE project beach berm width. Wind-blown sand had started to accumulate around the recently installed fence.

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Figure 5a – The quarterly comparison plots show significant beach and moderate dune erosion following Hurricane Sandy and winter storm Saturn. The beach berm was cut landward, flattened and lowered 3 feet in elevation. The seaward dune slope was cut landward 60 feet at the toe. By August the post-construction survey shows the USACE 2013 project beach provided about 200 feet of additional beach berm width and raised the elevation of the beach by up to 6 feet to elevation 7.5 feet NAVD88. Sand was also added to the seaward dune slope to restore to the original project design configuration. Sand was added to the nearshore seafloor during the project that resulted in a seaward advance of the shoreline position approximately 80 feet. By October 25th the project beach berm had eroded approximately 120 feet and the nearshore was scoured following 72 hours of strong onshore winds and waves. Much of the sand was transferred cross-shore filled the offshore trough that limited the net sand volume change.

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Figure 5b – The annual comparison plot shows the beach and nearshore despite the USACE 2013 project failed to regain its pre-storm configuration following Hurricane Sandy. Waves generated in early October 2013 by sustained onshore winds eroded nearly two thirds of the project beach berm and scoured the nearshore. Much of the sand was transferred offshore where 44.53 yds3/ft. of sand accumulated that raised the seafloor elevation by up to 3 feet. The offshore sandbar accumulation continued beyond the survey limits. The net volume change for the year was a modest gain of 3.49 yds3/ft. of sand that accumulated offshore while the shoreline position retreated landward 55 feet. One year following Sandy this site is still below pre-storm configurations despite sand placement during the USACE recent project. Wave scour cut into the project beach berm steepened the beacface slope and scoured a deep trough nearshore compared to the pre-storm conditions and following the USACE 2013 maintenance project.

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SH-112, is located on the open lot adjacent to the Villa Maria Catholic retreat that occupies the paper location of 112th Street. The profile line extends landward to a reference location along 2nd Avenue. An open grass lot occupies the city block between 2nd Avenue and the wooden bulkhead revetment. The wooden revetment runs parallel to the beach the entire length of the Borough along the oceanfront property lines and seaward street ends. The bulkhead is significantly offset landward at 111th Street, providing additional area for dune development to occur naturally. As a result the width of the primary dune is nearly 200 feet from the bulkhead to the seaward dune toe. Hurricane Sandy’s storm surge and waves tore into the beach and dune system completely removing the well-developed fore dune ridge. Despite a complete loss of the fore dune ridge at 112th Street the well-developed primary dune system maintained significant volume, width and height to protect oceanfront property. Sandy scoured 27.96 yds3/ft. of sand from onshore reducing the beach elevation about 3 feet and moving the shoreline position landward 76 feet. A modest 3-foot scarp remained in the dune where the fore dune had developed seaward of the primary dune ridge. Winter storm Saturn moved up the New Jersey coast four months following Sandy from March 5-6, 2013. Again the combined wave and surge effects further flattened and eroded the beach and scoured the nearshore seafloor. Despite the additional beach erosion the dune suffered no further losses at this location during Saturn. The 2013 USACE maintenance project was finished in this region prior to the June 12, 2013 survey. This project placed 54.95 yds3/ft. of sand into the system, advanced the shoreline position seaward 69 feet and raised the beach berm elevation to 7.5 feet NAVD88 that extended 200 feet seaward of the dune toe. The fill project raised the nearshore slope elevation up to 3 feet as the beach pushed seaward and sand moved offshore during the project. Sand was placed directly on the seaward dune slope during the project to restore the pre-Sandy dune configuration. A 13-foot deep trough over 150 feet wide separated the project beach from an offshore sand bar deposited during the earlier storm events. By October 28, 2013 nearly half of the project berm had eroded (100 feet) and the nearshore was scoured. Sand was transferred cross-shore to the offshore seafloor partially offsetting some of the onshore losses where it accumulated along with sand carried longshore from the updrift beach. The net result was a modest gain of 10.17 yds3/ft. of sand with a modest shoreline position retreat of 6 feet as the beachface slope and nearshore were scoured by the fall wave climate. Comparing the October 24, 2012 survey taken days before Hurricane Sandy arrived with the October 28, 2013 survey shows the beach volume increased a 40.47 yds3/ft. of sand above the pre-Sandy sand volume while the shoreline position retreated 10 feet landward. Following Sandy and the 2013 USACE project the beach width by October 28, 2013 still mimicked the 2012 pre-Sandy configuration. The nearshore was scoured but the accumulation of sand offshore during 2013 offset these losses and resulted in the largest net sand volume gain for the year. The volume of sand accumulating near the seaward profile limits as surveyed was 50,306 cubic yards in this cell the actual volume is higher as sand was transferred cross-shore well beyond the survey limits.

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Photoplate 6a - Photo was taken March 13, 2013 looking south along the dune toe from 112th Street. The beach was narrow and flattened with the foredune ridge eliminated by Hurricane Sandy and winter storm Saturn. A steep dune scarp remained in the seaward dune slope of the primary dune the abrupt vegetation line marks the post-Sandy dune scarp position along the dune crest.

Photoplate 6b - Photo was taken May 13, 2013 looking south along the dune toe from 112th Street. The beach remained narrow but the elevation increased as sand started to move onshore, note difference in exposed rock groin in distance with photo 6a. Wind-blown sand accumulated on the seaward dune slope that restored a gentler uniform slope.

Photoplate 6c - Photo was taken June 12, 2013 looking south along the dune toe from 112th Street. The 2013 USACE beach maintenance project restored the beach width and elevation to the original design template (note position of beach along groin in distance). Sand was added directly to the seaward dune slope during the project to restore the original design configuration but no fence had yet been installed.

Photoplate 6d - Photo was taken October 28, 2013 looking south along the dune toe from 112th Street. The early October 10, 2013 onshore wind event generated waves that eroded about half of the 2013 USACE project beach berm width. Wind-blown sand had started to accumulate around the recently installed fence.

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Figure 6a – The quarterly comparison plots show significant beach and moderate dune erosion following Hurricane Sandy and winter storm Saturn. The beach berm was cut landward, flattened and lowered 2 feet in elevation. The seaward foredune was eliminated pushing the slope landward 40 feet at the toe. By August the post-construction survey shows the USACE 2013 project beach provided about 180 feet of additional beach berm width and raised the elevation of the beach by up to 5 feet to about elevation 7.5 feet NAVD88. Sand was also added to the seaward dune slope to restore to the original project design configuration. Sand was also added to the nearshore seafloor during the project that resulted in a seaward advance of the shoreline position approximately 60 feet. By October 25th the project beach berm had eroded approximately 100 feet and the nearshore was scoured following 72 hours of strong onshore winds and waves. Much of the sand was transferred cross-shore filled the offshore trough that limited the net sand volume change.

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Figure 6b – The annual comparison plot shows the dune and beach were restored to its approximate pre-storm configuration following Hurricane Sandy. Waves generated in early October 2013 by sustained onshore winds eroded nearly half of the project beach berm and scoured the nearshore. Much of the sand was transferred offshore where 62.57 yds3/ft. accumulated, raised the seafloor elevation up to 4 feet these gains continued beyond the survey limits. The net volume change for the year was a substantial gain of 40.47 yds3/ft. of sand that accumulated offshore while the shoreline position remained relatively stable. One year following Sandy this site is essentially at its pre-storm configuration despite sand placement during the USACE recent project. Wave scour cut into the project beach berm steepened the beacface slope and scoured a trough nearshore compared to the pre-storm conditions and following the USACE 2013 maintenance project.

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SH-116, the 116th Street beach reference is set along the west side of 2nd Avenue. Seaward of the bulkhead at 116th Street is the best-established natural dune system in the Borough. A landward offset in the bulkhead just north of this site produced the area on which this dune developed, sheltered from storm overwash by the 114th Street groin and the bulkhead offset to the west. The dune system consists of two distinct ridges with a combined width of nearly 300 feet from the street end bulkhead to the seaward dune toe with a crest elevation of 16.5 feet NAVD88. Hurricane Sandy cut significantly into the beach width and elevation but the beach was sufficiently wider prior to Sandy to absorb and dissipate most of the wave energy and prevent any loss in the dune width. This was the only site to show no evidence of dune losses during Hurricane Sandy. During the storm the shoreline position retreated landward 77 feet with 20.22yds3/ft. of sand eroded from onshore while the beach elevation was lowered up to 4 feet along the old berm ridge. Winter storm Saturn’s combined wave and surge effects again further flattened and eroded the beach and scoured the nearshore with a storm debris line deposited along the seaward dune toe. Despite the additional beach erosion the dune suffered no losses at this location during Saturn. The 2013 USACE maintenance project was finished in this region prior to the June 12, 2013 survey. The project placed 17.57 yds3/ft. of sand into the system, advanced the shoreline position seaward 13 feet and raised the beach berm elevation to 7.5 feet NAVD88 that extended just 60 feet seaward of the dune toe. The limited fill placed here had little impact on the nearshore seafloor as the project raised the beach elevation but did not extend the overall width. No sand was placed directly on the seaward dune slope during the project as the post-Sandy dune configuration exceeded the design template. An 11-foot deep trough over 200 feet wide separated the project beach from an offshore sand bar deposited during the earlier storm events. Through the summer and early fall the project beach berm and dune at this site remained extremely stable. A small ridge of sand moved onshore and welded to the lower beachface that advanced the shoreline position seaward 46 feet. The October 2013 wind event with sustained onshore winds above 30 knots that persisted for 72 hours and generated wave scour nearshore cut a small trough in the seafloor but appears to have had limited effect on the beach. Further offshore a substantial volume of sand moved cross-shore and longshore to the site. The net result was a gain of 28.16 yds3/ft. of sand. Comparing the October 24, 2012 survey taken days before Hurricane Sandy arrived with the October 28, 2013 survey shows the beach volume had increased 30.13 yds3/ft. of sand above the pre-sandy sand volume while the shoreline position retreated 4 feet landward. The beach berm width on October 28, 2013 was 60 feet narrower than the 2012 pre-Sandy configuration. The net sand volume gain for the year resulted from the large accumulation of sand offshore to the profile limits. The seafloor gained 115,218 cy of sand offshore within in this cell.

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Photoplate 7a - Photo was taken March 13, 2013 looking north along the dune toe from 116th Street. The beach was narrow and flattened by Hurricane Sandy and winter storm Saturn. Saturn’s storm tidal wrack line reached the dune toe (above) with a modest dune scarp that remained in the seaward dune slope of the primary dune post-Sandy the abrupt vegetation line marks the dune scarp position along the dune crest now partially buried.

Photoplate 7b - Photo was taken May 13, 2013 looking north along the dune toe from 116th Street. The beach remained narrow but the elevation increased as sand started to move onshore, note difference in exposed pipline in distance with photo 7a. Wind-blown sand accumulated on the seaward dune slope that restored a gentler uniform slope and plants have colonized the new slope.

Photoplate 7c - Photo was taken June 12, 2013 looking north along the dune toe from 116th Street. The 2013 USACE beach maintenance project added a modest volume of sand restored the beach width and elevation to the original design template (note project pipe still on beach). No dune fence had yet been installed.

Photoplate 7d - Photo was taken October 28, 2013 looking north along the dune toe from 116th Street. This beach has remained relatively stable following the 2013 USACE project. Wind-blown sand has slowly accumulated around the recently installed fence.

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Figure 7a – The quarterly comparison plots show moderate beach and minor dune erosion following Hurricane Sandy and winter storm Saturn. The beach berm was cut landward, flattened and lowered 1.5 feet in elevation. The seaward dune slope remained relatively stable. By August the post-construction survey shows the USACE 2013 project beach provided about 50 feet of additional beach berm width at elevation 7.5 feet NAVD88 and raised the elevation of the beach by up to 2.5 feet. No sand was directly added to the seaward dune slope at this site. The October 28th survey conducted after the summer season and 72 hours of strong onshore winds and waves in early October showed a stable beach berm and modest accumulation of sand along the shoreline. Sand was scoured from the nearshore forming a trough but the sand was transferred cross-shore filled the offshore trough and developed a nearshore bar.

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Figure 7b – The annual comparison plot shows the seaward dune slope gained sand compared to its pre-Sandy configuration. Despite the 2013 USACE project the overall beach berm width retreated approximately 75 feet although the shoreline position remained relatively stable. The nearshore was scoured during the early fall sand was transferred offshore. Offshore 50.69 yds3/ft. of sand accumulated that raised the seafloor elevation up to 4 feet. Deposition continued well offshore beyond the survey limits. The additional sand added offshore resulted in a net sand volume gain of 30.13 yds3/ft. during 2013 compared to pre-Sandy conditions.

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SH-123, site 123 is located south of the development and just north of the terminal groin originally established by the Philadelphia District of the U.S. Army Corps of Engineers (USACE) feasibility and reconnaissance studies for Seven Mile Island. In 1994, the site was added to the NJBPN as part of an expansion of the State’s monitoring project and as a replacement cross section for site #112 erased from South Point by events in 1990 where the entire natural zone south of the terminal groin was eroded to a shoal below low tide. Because of this prior history of data collection and its proximity to Hereford Inlet, this site was included in the Borough’s beach monitoring project. The profile reference marker is located in a dense stand of bayberry west of a vehicle access path to the Hereford Inlet terminal groin. This region has benefited tremendously since the completion of the initial USACE project both from direct sand placement and from longshore currents that have carried a substantial volume of sand shed from the northern project beaches south toward South Pointe. The result has been a larger dune system that now completely buries the revetment once exposed along this beach and the formation of an expansive point that stretches over a mile from the terminal groin into Hereford Inlet. However, like the other Borough project beaches this location suffered significant erosion of the dry beach berm and dune during Hurricanes Irene and Sandy and several Nor’easters. When Hurricane Sandy moved onshore storm waves scoured out the narrow beach that remained and reduced the elevation by up to 4 feet and cut into the seaward dune slope. Over 40 feet of the seaward slope was removed to the crest where a 7 to 8-foot scarp remained. The shoreline retreated landward 124 feet and the onshore dune and beach volume reduced by 22.80 yds3/ft. of sand from the storm. Winter storm Saturn’s combined wave and surge effects further flattened and eroded the beach and cut into the seaward dune toe. The resulting beach was extremely narrow and low in elevation that allowed astronomical tides to periodically reach the dune toe. Within two months the USACE had started its federal maintenance project for 2013 at this location. The 2013 USACE maintenance project was finished in late May as the project progressed from south to north. The project placed 25.38 yds3/ft. of sand into the system, advanced the shoreline position seaward 148 feet and raised the upper beach elevation to 7.5 feet NAVD88 that extended 200 feet seaward of the dune toe. Sand was placed directly on the seaward dune slope during the project to restore the dune configuration to the design template. Through the summer and early fall the project beach berm and dune eroded extremely rapidly. A shallow platform 1-2 feet above the datum remained near the project shoreline position that reduced the net shoreline position retreat to just 58 feet. The October 2013 wind event with sustained onshore winds above 30 knots persisted for 72 hours and generated wave scour nearshore cutting a trough in the seafloor. Further offshore a substantial volume of sand moved cross-shore that reduced the net volume loss but the onshore losses offset any modest gains offshore. The net result was a loss of 36.30 yds3/ft. of sand. Comparing the October 24, 2012 survey taken days before Hurricane Sandy arrived with the October 28, 2013 survey shows the beach volume increased 5.28 yds3/ft. of sand above the pre-sandy sand volume while the shoreline position retreated 27 feet landward. Following Sandy and the 2013 USACE project the beach width by October 28, 2013 was 60 feet narrower and the seaward dune slope 30 feet landward compared to the 2012 pre-Sandy configuration. The net gain for the year resulted from the large accumulation of sand on the nearshore bar offshore to the profile limits.

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Photoplate 8a - Photo was taken March 13, 2013 looking north along the dune toe from near the terminal groin at 123rd Street (paper). The beach was very narrow and flattened by Hurricane Sandy and winter storm Saturn. Saturn’s storm tidal wrack line reached the dune toe (above) with a modest dune scarp that remained in the seaward dune slope of the primary dune, the abrupt vegetation line marks post-Sandy dune scarp position along the dune crest now partially buried.

Photoplate 8b - Photo was taken May 13, 2013 looking north along the dune crest from 116th Street. The beach remained narrow but the USACE 2013 project was under way to restore this section of beach. In the photo slurry from the discharge pipe is located at the site as bulldozer build dikes and grade the project beach.

Photoplate 8c - Photo was taken June 12, 2013 looking north along the dune toe from 123rd Street. The 2013 USACE beach maintenance project added sand restored the beach width and elevation to the original design template (note project pipe still on beach). Sand was also placed along the seaward dune slope to restore the original dune configuration. No dune fence had yet been installed.

Photoplate 8d - Photo was taken October 28, 2013 looking north along the dune toe from 123rd Street. This beach has eroded quickly following the 2013 USACE project. The shallow platform visible in the photo above delineates the project beach extents. Nearly 150 feet of the project beach berm was lost. Wind-blown sand has slowly accumulated around the recently installed fence.

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Figure 8a – The quarterly comparison plots show significant beach and moderate dune erosion following Hurricane Sandy and winter storm Saturn. The beach berm was cut landward, flattened and lowered 3 feet in elevation. The seaward dune slope was cut landward 60 feet and formed a scarp. By June the post-construction survey shows the USACE 2013 project beach provided about 200 feet of additional beach berm width at elevation 7.5 feet NAVD88 and raised the elevation of the beach by up to 7 feet. Sand was directly added to the seaward dune slope at this site to restore the seaward dune slope to its original design width. The October 28th survey conducted after the summer season and 72 hours of strong onshore winds and waves in early October showed the beach berm had eroded and nearshore was scoured. Sand scoured from the nearshore formed a trough but the sand was transferred cross-shore and partially filled the offshore trough and developed a nearshore bar.

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Figure 8b – The annual comparison plot shows the seaward dune slope and beach have not recovered as compared to its pre-Sandy configuration. Despite the 2013 USACE project the overall beach berm width and dune retreated. The nearshore was scoured during the early fall sand was transferred offshore. Offshore 47.62 yds3/ft. of sand accumulated, raised the seafloor elevation up to 3 feet and continued beyond the survey limits. The additional sand added offshore resulted in a modest net sand volume gain of 5.28 yds3/ft. during 2013 compared to pre-Sandy conditions.

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Summary Hurricane Irene, the October 2011 northeaster and Sandy combined to remove 121% of the sand placed on the Borough’s beaches during the 2011 USACE project nearly 702,000 cubic yards of sand from the beaches and dunes. During “Superstorm Sandy” the beaches lost 380,859 cubic yards of sand from just the dune and beach not including nearshore losses. Much of the eroded sand has moved south to the Hereford Inlet shoreline extending the South Pointe beaches into the inlet over 500 feet just this past year and additional sand was carried offshore beyond the profile extent using current methods. Sand was also transferred further offshore to deeper water to form massive shore parallel bars. Superstorm Sandy scoured a deep, wide trough in the seafloor that separated the offshore deposit from the beach and hampered natural landward cross-shore transport. With most of the eroded sand transferred south towards South Pointe or offshore to deeper water natural recovery was limited. Hurricane Sandy’s landfall in New Jersey on October 29, 2012 caused significant erosion to the beach and dune along the Stone Harbor shoreline but the USACE project proved essential in protecting oceanfront property and infrastructure. Beach widths were reduced and the elevations lowered up to 4 feet as the storm surge and waves inundated the shoreline and cut steep scarps into the dune system. After Sandy, the shoreline positions at the 8 study beaches had retreated on average 81 feet with an average volume loss of 29.84yds3/ft. of sand from the beach and dune. The net loss to the Borough’s oceanfront was 380,859 cubic yards of sand removed from the beaches and dunes. Despite these losses the USACE project dunes and earlier-built municipal dunes remained largely intact protecting the oceanfront property and infrastructure from severe damage. An emergency re-nourishment effort by the USACE for Stone Harbor was initially authorized following Irene then expanded to include damages suffered during Sandy that allowed work to commence within 6 months of Sandy. During late spring and summer 2013, Norfolk Dredging Company contracted by the USACE completed work to restore the beach to its full design template. Surveys conducted by the CRC before and after the project show a placement volume of 715,346 CY of sand. The 2013 USACE project restored the Borough’s beaches to full design template 211,850 CY of sand above the pre-Sandy conditions. Beach berm elevations were raised to 7.5 feet NAVD88 and extend seaward from the dune toe by up to 220 feet. Restoration of the entire Stone Harbor beachfront to the federal template improved both the recreational beach and enhanced storm protection to ensure Stone Harbor is prepared for future storm events to prevent damage to property and infrastructure. The emergency funding status of the project allowed the USACE to fully fund the re-nourishment with federal dollars saving the local government and taxpayers from covering the project cost. The emergency funding also financed planting dune grass, installing sand fencing, and beach crossover work in the project area. Following completion of the USACE project in summer 2013 the beach berm began to erode. The net sand volume change onshore following the project was -240,687 cubic yards of sand eroded from the project beach berm. By October 28, 2013 at most of the sites with the exception of 116th Street the shoreline position retreated. Shoreline changes were highly variable and ranged from a moderate advance of 46 feet at 116th Street to 72 feet of retreat at 82nd Street. The project beach berm widths eroded landward up to 150 feet and each site showed onshore sand volume losses except at 116th Street where there was a modest gain (3.77yds3/ft.). Onshore losses ranged from -13.90 to -33.68 yds3/ft. of sand from above the zero datum elevation. Offshore the sand volume changes were all positive as sand was swept cross-shore from the beach to the seafloor, the net effect offset much of the onshore losses to reduce the net sand volume loss for the study interval. The total net sand volume change over late

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summer and early fall of 2013 was a very modest loss of 22,287cy of sand from across the entire Stone Harbor oceanfront including the dunes, beaches and offshore seafloor. Much of these onshore losses were likely driven storm waves generated by a period of 72 hours with sustained 30 plus knot onshore winds on and around October 10, 2013. This past year was an active period following Hurricane Sandy. Winter storm Saturn impacted the shore in March 2013followed by the 2013 USACE maintenance project that started in late spring and was completed during the summer. The fall/winter storm season started in early October with the arrival of 72 hours of 30 knot plus onshore winds around October 10, 2013 that cut into the project beach. The net result for 2013 along the Borough’s shoreline was an annual sand volume gain of 185,303cy, from just prior to the arrival of Sandy on October 24, 2012 to one year later on October 28, 2013. The USACE project added 674,224cy of sand (USACE reported pay volume). This project replaced losses suffered during Hurricane Irene, the October 2011 northeaster and Sandy combined a total of nearly 702,000 cubic yards of sand eroded from the beaches in less than a year and a half. An additional 108,121cy of sand was lost during Saturn and the October 10, 2013 storm (wind) event. Unfortunately, onshore erosion to the 2013 USACE project was extensive a third to two thirds of the project berm width was lost but sand was transferred offshore offsetting some of the onshore project losses limiting the net profile volume change. Only the site at 82nd suffered a net sand volume loss for the year with losses onshore and offshore, a net loss of 35.05 yds3/ft. of sand. In contrast only one site 90th street showed a net shoreline position advance for the year. Onshore project beach losses during the fall of 2013 were between -13.90 to -33.68 yds3/ft. of sand only 116th Street showed a modest net sand volume gain (3.77yds3/ft.) onshore in 2013. The net onshore volume change for the year from October 24, 2012 to October 28, 2013 was a loss of 109,969 cubic yards of sand. In contrast, offshore 295,271 cubic yards of sand accumulated over the year likely derived from the project beaches and storm losses transferred cross-shore. The cross-sections clearly indicate this offshore accumulation continued beyond the survey limits adding up to another 25-30% of additional sand to the total volume contained in this shore parallel sand bar system that extended the entire length of the Borough’s oceanfront shoreline. Predominant longshore currents will carry sand south towards South Point and the Hereford Inlet ebb tidal shoal system. Some of this sand may return to the beaches via cross-shore transport once the weather and wave climate favor natural beach building processes in spring/summer 2014. The location and volume of sand returning to each beach will vary depending on weather patterns and wave climate conditions. During the fall 2013 survey there was an 8-10 foot deep nearshore trough along the entire Borough oceanfront shoreline that separated this offshore sand deposit from the beach. How that feature developed over the winter will have a significant impact on determining the rate of transfer between the beach and offshore. Conclusion/Recommendations Although the area of South Pointe is a valued natural area and shore bird habitat, the region represents a vast source of potential sand to harvest in a sustainable manner to mitigate the annual losses within the developed section of Stone Harbor. As more sand is placed into the system on the northern beaches, erosion and littoral currents combine to transport the sand shed from these beaches south toward the South Pointe spit causing continued growth. Moving forward a sand backpassing program should be considered to harvest excess sand from South Pointe beaches and transport it back to the erosional shoreline between 93rd Street and 110th Street in an effort to recycle sand and extend the duration required between major re-nourishment cycles. Although potentially controversial due to the

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environmental sensitivity of nesting shore birds on South Pointe beaches it still could prove a valuable source of sand for the future without threatening nesting areas if the program is properly managed and executed prior to March 1st of any given year. The rapid erosion following this year’s USACE project demonstrates the continuing need to provide regular maintenance between major projects to maintain a higher level of storm preparedness. The recommendation provided last year remains valid and is the best alternative to continued reliance on large scale nourishment projects triggered only after the beaches degrade to a critical level to warrant federal (USACE) maintenance projects. Reliance on this traditional method of periodic nourishment places the community at potential additional risk to storm damages as the dune and beach system degrades between nourishment cycles. A sand backpassing program would make the community more resilient by through regular maintenance of the beach to diminish the rate of degradation to the design template ensuring the beach and dune system are sufficient to provide ample storm protection during the next storm. The recent increase in storm frequency going back to November 2009 and more recently with Hurricane Irene, a Northeast Storm on October 29, 2011 and Hurricane Sandy on October 29, 2012 shows the critical importance in maintaining a wide beach with a higher elevation berm and well-developed dune system for protecting oceanfront property and infrastructure. Regions along the Jersey shore were municipalities have been active in maintaining an engineered beach weathered the recent storm events better with less oceanfront property and infrastructure damage compared to areas without similar projects in place. No one can predict with certainty when and where the next storm will impact the coast but, it is certain that an event will occur. Coastal communities must remain diligent and be prepared by maintaining their shoreline and increasing their storm protection by learning the lessons these storms have provided. The CRC continued to survey Hereford Inlet and the surrounding shoreline as part of an ongoing monitoring program for the State of NJDEP BCE (Bureau of Coastal Engineering). These surveys have revealed that the South Pointe spit continues to grow in width, elevation and length as additional sand shed from project beaches in the north moves south carried by the dominant direction of littoral currents. The point has continue to grow at a rate of about 500 feet a year and is now over a mile long stretching from the terminal groin south of 123rd Street to the tip of the point. Considering the rate of spit growth and the need for Congressional authorization for funding to allow a continued commitment by the USACE to replenish the Stone Harbor beaches this depositional shoreline should be considered as a source of sand to harvest annually (as a maximum frequency in doing it). By harvesting sand outside the shorebird nesting season their use of this sensitive habitat is protected. Harvested sand could also be used to enhance nesting habitat while excavation could be done in a manner to create shoreline foraging areas. Recycling and reusing sand from South Pointe to maintain the erosional beaches to the north could both establish a more sustainable beach system and reduce maintenance cost. Reducing the frequency of expensive hydraulic beach nourishment projects will save all three partners money (municipality, state and federal government). Recent contracts have seen the mobilization of the dredge and crews exceed a million dollars, with an $8 to $9.00 per yard pumping charge. While Stone Harbor’s share of a federal project is 25% of the 35% non-federal cost share (8.75% of project cost) extending the time between big projects with sand recovery at $500,000 per effort could save money in the long term. Similar programs have been initiated in neighboring Cape May County communities of Avalon and North Wildwood to help establish a more cost effective approach to managing regional sediment budgets and beach management issues. Both of these projects were cost shared between NJ DEP and the municipality with the North Wildwood project subject to FEMA reimbursement under the disaster

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declaration for Hurricane Irene. The USACE is investigating a similar project in the Wildwoods to regionally manage the islands sediment budget through a sand backpassing program with potential benefits for all three island communities’ beach management concerns. Recommendations as result of recent events have not changed significantly from previous reports. No further addition needs to be made to the existing dunes in the form of direct construction of

wider or higher dunes. Post-project wind transport should add substantially to dune growth similar to past episodes documented by surveys. The dune erosion was largely confined to these wind-deposited fore-dunes that developed around installed dune-toe fencing.

Following maintenance, fence along the lower third of the seaward slope (in a zigzag pattern) of the dune system immediately (partially completed) to force deposition of the wind-transported sand forward and lower in elevation on the upper seaward toe slope of the dunes. This pattern prevents excessive elevation to the primary dune. Fence installation should follow recommendations summarized in past CRC reports as obtained from the USDA circular defining the installation of fence and American beach grass. CRC could provide additional copies if needed.

New regular interval maintenance efforts including sand harvesting and transfer from South Pointe to the project area should be considered to maintain the beach near its full design template through recycling longshore erosional losses to reduce the frequency of large scale beach nourishment projects and increase the resiliency of Stone Harbor’s dune and beaches for future storm events.

It is recommended to load the deposition of all maintenance sand strongly to the northern beaches, because sand tends to move south between groin cells fairly quickly.

annual report for 1999 - stockton...

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