A REVIEW OF THE CONDITION OF THE MUNICIPAL BEACHES AS A RESULT OF HURRICANE SANDY IN THE BOROUGH OF STONE HARBOR, CAPE MAY COUNTY, NEW JERSEY

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1 A REVIEW OF THE CONDITION OF THE MUNICIPAL BEACHES AS A RESULT OF HURRICANE SANDY IN THE BOROUGH OF STONE HARBOR, CAPE MAY COUNTY, NEW JERSEY View along the dune scarp from 103 rd Street on October 31, 2012 following landfall of Hurricane Sandy. The US Army Corps of Engineers (USACE) completed a maintenance renourishment project on the Borough beaches in the spring of Although the beaches and dunes suffered significant erosion the project was essential in protecting oceanfront property and infrastructure. The pavilion in the distance was located within the dunes before Sandy and is now exposed at the erosional scarp. PREPARED FOR: THE BOROUGH OF STONE HARBOR 9508 SECOND AVENUE STONE HARBOR, NJ PREPARED BY: THE RICHARD STOCKTON COASTAL RESEARCH CENTER 30 WILSON AVENUE PORT REPUBLIC, NEW JERSEY November 26, 2012

2 Introduction: This annual report presents the status of the beaches within the Borough of Stone Harbor for In 2011 the US Army Corps of Engineers (USACE) in a maintenance beach renourishment project placed 580,000 cubic yards (cy) of sand on the beaches between 90 th Street and 123 rd Street raising the elevations up to 8 feet and creating approximately 200 feet of extra width on the beach berm. Hurricane Irene combined with the October 29, 2011 Northeaster to remove nearly 164,000 cy of the sand placed during the USACE project before the end of During the first half of 2012 the beaches continued to lose sand through longshore drift as the weather conditions were relatively calm over the winter and spring. From December 2011 to June 2012 the Stone Harbor shoreline lost another 142,646 cy of sand. The volume loss occurred offshore because the recreational beach gained nearly 64,000 cy as weather and sea conditions were favorable for beach building and moving sand landward. This trend of onshore beach building and offshore loss continued through the summer into early fall until the arrival of Hurricane Sandy, the second hurricane in about 14 months to make landfall in New Jersey. The Richard Stockton College of New Jersey Coastal Research Center (CRC) completed the fall review of the municipal beaches, survey #37 on October 24, 2012 following what was a relatively mild weather pattern and just prior to the arrival of Hurricane Sandy on October 29, Semi-annual shoreline and sand volume changes were calculated between survey #36, and the most recent study. An emergency survey was conducted following Sandy on October 31, 2012 at selected sites to determine the dune and beach volume changes along with shoreline changes. The emergency survey utilized RTK GPS with its focus restricted to onshore changes only, no bathymetry data was collected to show the offshore changes. Enclosed with this annual report are comparison profile plots that show beach configuration changes between the last three semi-annual studies at the eight monitoring sites together with the post- Sandy emergency survey from October 31, (survey299) included. Weather Conditions Relatively mild weather patterns prevailed through December 2011 to October Calm seas and mild wind conditions were favorable for moving sand landward and for natural beach building to take place. This pattern abruptly changed with the approach and arrival of Hurricane Sandy in late October, Hurricane Sandy made landfall near Atlantic City about 8 p.m. ET on October 29, 2012, as "Post- Tropical Cyclone Sandy, it still packed hurricane-force winds but having lost the characteristics of a tropical storm about an hour before land fall. Sandy was the second named storm to have struck New Jersey in less than two years following Irene which made landfall in August Sandy's strength, angle of approach and arrival during full moon high tides combined to produce a record storm surge of water into New York City and along the northern New Jersey shoreline. Stone Harbor located south of the eye avoided the full wrath of Sandy s strongest winds that topped 90 mph and storm surge, sparing the community from potentially facing similar devastation of property seen in Ocean and Monmouth Counties. Impact from Hurricane Sandy The USACE engineered beach provided sufficient storm protection during Sandy s landfall to limit oceanfront property and infrastructure damages. The beach and dune system suffered significant erosion 1

3 with up to 10-foot dune scarps cut into the seaward dune slope. The dune crest remained relatively intact, which prevented major over wash by storm waves that create dune breaches that could have resulted in major surge damage. Data collected during the emergency survey will provide the Borough with an initial beach damage assessment and estimates of the dune and beach losses for future restoration. A comparison of the data collected on October 24, 2012 to post-sandy showed the dune and beach lost over 380,800 cubic yards of sand during the storm. 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 profilemonitoring 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 feet. Each of the groin compartments or cells along the Borough beachfront contains one profile line. Work continues on a semi-annual monitoring schedule. The following list describes the selected sites and locations: SH nd Street Border with Avalon 84 th St. groin SH th Street 84 th St. groin 92 nd St. groin SH th Street 92 nd St. groin 98 th St. groin SH rd Street 98 th St. groin 106 th St. groin SH th Street 106 th St. groin 111 th St. groin SH th Street (paper street) 111 th St. groin 114 th St. groin SH th Street 114 th St. groin 122 nd St. groin SH rd Street (paper street) 122 nd St. groin terminal groin Stone Harbor Beach Performance Hurricane Irene in 2011 was the first hurricane to make landfall in New Jersey since The maximum sustained winds on land in New Jersey were 71 MPH with gusts nearly 90 MPH. The storm surge accompanying the storm reached 3.0 feet. In 2012 Sandy became the second named storm to make landfall in New Jersey in successive years. Damages to the Borough s beaches from Hurricane Irene were significant. Hurricane Irene and a October 2011 nor easter reduced the sand volumes placed by the USACE but the project was successful in protecting homes and infrastructure within the Borough. The dune toe was eroded into a scarp along some of the municipal beaches, but no major damage or breach in the dunes occurred. Relatively mild storm and wave climate conditions persisted along the Jersey shore after Irene and the northeaster of October 2011 that continued through the spring and summer of Offshore sand from the bar system has pushed landward under favorable sea conditions this year filling the troughs that had developed after last year s storms. Gentle summer wave conditions and southeast swells continued to move sand landward eventually adding to the onshore beach volume and width by the end of the summer season. While the beaches and dune gained a modest sand volume onshore offshore losses were more significant as longshore currents moved sand in a southerly direction toward Hereford Inlet. 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 dune stability was maintained providing ample storm protection for oceanfront properties once again. Damage to beach 2

4 access crossovers, ramps and pavilions was extensive but the public infrastructure inland was largely protected. The USACE engineered beach has now 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. The USACE is scheduled to perform maintenance nourishment in early 2013 to restore these now severely eroded beaches as part of its long term commitment to maintain Stone Harbor s storm damage reduction project beach. 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 expressed in cubic yards of sand per linear foot of beachfront (yds 3 /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 Semi-Annual Shoreline and Profile Sand Volume Changes June 2012 to October 24, 2012 Profile Shoreline Volume Cell Cell Volume Number Change Change Distance Change (feet) (yds 3 /ft) (feet) (yds 3 ) SH ,381 19,527 SH ,240-9,453 SH ,680-1,562 SH ,208-3,996 SH ,433 1,935 SH ,739 SH ,273-16,888 SH ,058-3,640 13,077 ft. Total Volume Change = -17,816 The total net sand volume change over the summer and early fall of 2012 was a very modest loss of 17,816 cy of sand from across the entire Stone Harbor oceanfront including the dunes, beaches and 3

5 offshore seafloor. Shoreline changes were variable and ranged from a modest advance of 13 feet at 82 nd Street to up to 29 feet of retreat nearby at 95 th Street. Onshore sand volume changes above the zero datum elevation were modest at each site. Offshore the sand volume changes were also relatively modest, the net effect of cross-shore transport and long-shore drift on the Borough s beaches was a modest average sand volume loss of 0.87 yds 3 /ft. of sand over the entire shoreline distance for the Stone Harbor as more sand moved out of the study area south towards Hereford Inlet. Sand moving into Stone Harbor from the Borough of Avalon was likely responsible for the net gain at 82 nd Street. Table 2 below displays the changes in shoreline positions and sand volume changes for the onshore area from six months ago. Shoreline changes are calculated in the same manner as above and show no difference from Table 1. Onshore sand volume changes are calculated for each individual profile site by computing the cut and fill cell changes above the zero elevation datum only with the previous survey. These values are expressed in cubic yards of sand per linear foot of beachfront (yds 3 /ft); the total onshore study area beach volume change is calculated using this value and as described above for Table 1. Table 2 Stone Harbor Semi-Annual Survey Onshore - Beach & Dune Area Only Shoreline and Sand Volume Changes June 2012 to October 24, 2012 Profile Shoreline Volume Cell Cell Volume Number Change Change Distance Change (feet) (yds 3 /ft) (feet) (yds 3 ) SH ,381 5,082 SH ,240-3,024 SH ,680-1,747 SH , SH ,433 1,935 SH SH ,273 9,865 SH ,058 1,344 13,077 ft. Total Volume Change = 14,286 Table 2 shows the onshore sand volume changes, which includes the dune system and recreational beach, to be a modest gain or a very modest loss at each site. The Borough s total onshore oceanfront volume change for summer-fall 2012 was modest gaining 14,286 cubic yards of sand prior to Sandy s landfall. This represents an average gain of just 1.14 yds 3 /ft. of sand over the entire 13,077 feet of municipal oceanfront beach comprising the study area. These modest volume changes again emphasizes 4

6 the nature of cross-shore transport influenced by longshore drift persistently at work along the Stone Harbor shoreline as southerly currents shift sand in a southerly direction over time. Table 3 below displays the shoreline position and sand volume changes at each of the eight sites for the 2012 monitoring year, prior to Sandy. Shoreline changes are calculated by comparing the zero datum positions in the current survey to the previous year s December 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 (yds 3 /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 Annual Changes Semi-Annual Survey Study Area Shoreline and Profile Sand Volume Changes December 2011 to October 24, 2012 Profile Shoreline Volume Cell Cell Volume Number Change Change Distance Change (feet) (yds 3 /ft) (feet) (yds 3 ) SH ,381 26,543 SH ,240-25,670 SH ,680-5,477 SH ,208-38,463. SH ,433-20,707 SH ,639 SH ,273-55,143 SH ,058-17,552 13,077 Total Volume Change = -157,108 Along the Borough s shoreline the net annual sand volume loss was 157,108 cy, prior to the arrival of Sandy. All of these losses occurred offshore while onshore each location showed modest gains in volume and shoreline. The only site to show a moderate net sand volume gain was 82 nd Street, where sand shifting south from Avalon combined with sand transferred cross-shore to the beach and to the nearshore slope offsetting the loss on the seafloor further offshore. Hurricane Irene and the October 2011 northeaster eroded and reduced the sand volumes placed during the 2011 USACE by 164,155 cubic yards but the project was successful in protecting homes and 5

7 infrastructure within the Borough. This year s annual loss combined with the 2011 post-construction loss represents approximately 55% of the sand volume placed during the 2011 USACE project indicating just 45% of the volume remained in place prior to the arrival of Sandy. Fortunately the dune had remained largely intact, which was represented by the volume of sand retained that provided critical protection for ocean front infrastructure and property in Stone Harbor from storm waves and surge experienced during Sandy. The continued net volume losses offshore from the study area and growth of South Pointe demonstrate the dominate process, minus storm events, affecting Stone Harbor s shoreline is longshore drift pushing sand in a southerly direction towards Hereford Inlet. 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. Table 4 below displays the changes in shoreline positions and sand volume changes for the entire study area as a result of Sandy. Shoreline changes are calculated by comparing the zero datum positions in the post-storm RTK GPS survey #299 to survey #37. 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. 6

8 Table 4 Stone Harbor Emergency Post-Sandy Survey Onshore Beach & Dune Area Shoreline and Sand Volume Changes October 24, 2012 to October 31, 2012 Profile Shoreline Volume Cell Cell Volume Number Change Change Distance Change (feet) (yds 3 /ft) (feet) (yds 3 ) SH ,381-49,564 SH ,240-52,528 SH ,680-47,611 SH ,208-75,734 SH ,433-41,113 SH ,575 SH ,273-54,666 SH ,058-34,068 13,077 Total Volume Change = -380,859 Table 4 above shows 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 has been 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 has moved south to the Hereford Inlet shoreline where the South Pointe beaches have continued to expand south into the inlet by 500 hundred 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 123 rd 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 SH-82, located at 82 nd street this beach and most of the Borough shoreline received sand during the spring 2011 ACOE re-nourishment project. Hurricane Irene and the October northeaster eroded the project beach reducing the dry beach width by approximately 100 feet. By June 2012, calmer weather 7

9 that prevailed over most of the winter and spring was favorable for natural beach building to occur and sand to move back onshore, restoring some of the lost beach width and elevation. The process continued throughout the summer months. Hurricane Sandy made landfall on October 29 th 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 23 rd survey. Prior to Sandy this section of beach had gained 19.22yds 3 /ft. of sand with a shoreline advance of 39 feet for the year. Sandy removed 31.91yds 3 /ft. of sand from the dune and beach resulting 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. Photograph 1. Above are four composite shots before and after Sandy, looking south from 82 nd Street. The top left photo was taken in June 2012 and shows the wider beach conditions after favorable weather moved sand onshore. Top right photo was taken in October before Sandy and shows the sand had moved higher onto the beach raising the recreational beach elevation with some sand collecting around dune fence installed along the seaward toe. Both photos on the bottom show post Sandy dune and beach conditions. Only the fence post remain where the developing fore dune existed a week earlier and the beach elevation and width are dramatically reduced. In spite of the losses, the photo on the bottom right shows significant dune width still remained post Sandy, landward of the oceanfront properties that protected homes and provides future storm protection. 8

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11 SH-90, located at 90 th Street, this beach also received sand during the 2011 ACOE project. Hurricane Irene and the October nor easter combined to remove nearly 100 feet of the dry beach berm constructed during the project. Much of the eroded sand was carried offshore to the sand bar system. By June 2012 sand had begun to move landward, adding to the shoreline width and partially filling the offshore trough. Sand continued to move onshore and higher up the beach over the summer months as the weather remained calm through the first nine months of The net change was a shoreline advance of 10 feet and net profile volume loss of yds 3 /ft. of sand as offshore losses offset onshore gains. 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 yds 3 /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. Photograph 2. The two views above to the north taken at 90 th Street from the upper beach in June and October, 2012 respectively, show the substantial beach width and elevation that prevailed through most of the year. Along the seaward dune toe sand accumulated over the year along the installed fence line. Both bottom photos show the beach and dune conditions post Sandy. The developing fore dune and fence line has been removed with little trace and the beach width and elevation reduced. Again, despite the storm damages ample dune system remained to protect the oceanfront homes from wave and surge damage. 10

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13 SH-95, at 95 th Street the beach lost nearly 100 feet of the dry recreational beach berm constructed during the 2011 ACOE project during Hurricane Irene and October northeast storm in Over the winter and spring, calmer sea conditions allowed sand to move landward adding sand to the beachface. Prevailing favorable weather and sea conditions continued through the summer allowing beach building to continue into early fall. By October 23, 2012 the shoreline had advanced 20 feet seaward the beach width and elevation enhanced and a small fore dune developed along the seaward dune toe. Offshore losses offset onshore gains for a modest net profile volume loss of 3.26 yds 3 /ft. of sand prior to Hurricane Sandy s arrival. Sandy caused significant erosion at 95 th 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 yds 3 /ft. of sand removed from the dune and beach volume with a 4 to 6-foot scarp in the seaward dune face. Photograph 3. Above the top views to the south at 95 th Street show the wider and higher recreational beaches present for the summer season and development of a fore dune in The bottom set of pictures shows the dune and beach erosion caused by Sandy. The developing fore dune was completely removed leaving a 6 to 8 foot-high scarp in the seaward dune slope to the crest. Beach elevations were reduced up to 4 feet and the shoreline retreated 75 feet. 1

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15 SH-103, at 103 rd Street the beach like those to the north lost nearly 100 feet of the 2011 project dry beach berm width after Hurricane Irene and the October Nor easter. Over the relatively calm winter and spring season sand started to move back onshore adding nearly 23 feet to the shoreline width from December The trend continued into the summer months producing a wider and higher recreational beach and fore dune development. For most of 2012 the shoreline advance was a modest 9 feet while offshore losses offset onshore gains for a net profile volume loss of yds 3 /ft. of sand. Hurricane Sandy dramatically reversed the trend, the beach and dune were eroded the shoreline position retreated 90 feet and the beach elevation was 4 feet lower across most of the remaining beach. The dune was cut back about 40 feet at the toe eliminating the fore dune feature and leaving a 5 to 7-foot scarp at the seaward crest. Onshore Sandy removed 29.90yds 3 /ft. of sand from the dune and beach. Photograph 4. Both of the top views to the north at 103 rd Street show dune and beach conditions during 2012 prior to Sandy. Along the seaward dune toe a fore dune was developing with early colonizing plants established by October 23, 2012 and the dry recreational beach was wide and provided ample space for summer season beach patrons. The two lower photos taken from similar positions as above show the dune and beach conditions post Hurricane Sandy slope. The beach is significantly lower and the dune has eroded landward exposing the pavilion in the distance to the ocean. 1

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17 SH-108, the 108 th Street beach lost nearly all the dry berm width (150 ft.) placed here by the 2011 project during Hurricane Irene and the October 2011 northeaster. From December 2011 to June 2012 the shoreline width advanced 29 feet but the onshore gain was offset by losses offshore for a net profile volume loss of yds 3 /ft. of sand. Favorable beach building conditions continued through the summer but with limited sand available offshore at this site natural recovery was minimal. From December 2011 to October 24, 2012 the shoreline position advanced 21 feet but had a net profile volume loss of yds 3 /ft. of sand as offshore losses offset the smaller onshore gain. When Sandy struck the coast, the narrower beach width and lower berm elevations provided less storm protection for the dune system, in this region. The surge and waves from Sandy cut into the dune slope removing the fore dune and leaving up to 7 feet 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 retained sufficient volume and height to protect oceanfront properties. Photograph 5. The top left photo shows the lower beach elevation and width prior to the summer. By October 24, 2012 the beach had gained enough elevation and width to provide ample recreational use. Along the seaward dune toe a new fore dune ridge developed throughout the spring and summer. Both lower views to the north taken post Sandy at 108 th Street show the nature of the storm erosion. The beach is narrower and lower in elevation and the dune is cut back to a steep scarp. A single post remained where the fore dune was developing prior to Sandy. The small clump of plants remaining in the foreground of the left photograph corresponds with the dark green group of plants growing in the swale between the foredune and the constructed dune and its regular rows of plants. 1

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19 SH-112, the 112 th Street beach pattern reflected the same general trends seen at the northern sites in the Borough. The June 2011 dry beach berm established by the ACOE project was nearly eroded away during Irene and the October 2011 storms. The dry berm width retreated landward over 120 feet. Over the winter and spring of 2012 some sand moved back onshore under favorable weather conditions. The shoreline position advanced 25 feet but the net profile volume lost yds 3 /ft. of sand, as material offshore moved south away from the site during the early part of Dune and beach configurations were essentially retained throughout the summer with modest changes onshore. The shoreline positioned for the year prior to Sandy advanced nearly 22 feet but the net profile volume loss yds 3 /ft. of sand as beach/dune gains were offset by offshore losses. Hurricane Sandy s landfall in New Jersey made these seasonal changes moot as the storm 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 112 th Street the well-developed dune system maintained significant volume, width and height to protect oceanfront property. Sandy scoured yds 3 /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. Photograph 6. The top views to the south taken in June, 2011 and on October 24, 2012 at 112 th Street shows development of the large fore dune feature and wide beaches remaining from the 2011 nourishment project. In the pair of photos taken after Sandy from essentially the same location the erosion is evident. The fore dune feature is completely removed and the beach width and elevation significantly reduced. 1

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21 SH-116, the 116 th Street beach was the only beach to remain stable to slightly accretional since completion of the 2011 ACOE project, prior to Hurricane Sandy. Sand moved onshore added to the beachface and a massive bar system was in place offshore raising the elevation of the seafloor in the nearshore region during the spring. Some of the sand moved onshore in the summer under favorable conditions but more appears to have moved longshore to the south for a net profile sand volume loss. The net change since December 2011 to October 24, 2012 was a shoreline position advance of 5 feet but a net profile volume loss of yds 3 /ft. of sand all lost from the offshore limits of the profile. Hurricane Sandy cut significantly into the beach width and elevation but the beach was sufficiently wide 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 20.22yds 3 /ft. of sand scoured from the beach reducing the elevation up to 4 feet along the old berm ridge. Photograph 7. In the top two views to the south at 116 th Street taken from the same location on the beach in June 2012 and on October 24, 2012 the beach width had expanded and elevation increased, fore dune growth was occurring and new fence installed along the seaward dune toe was capturing wind-blown sand. The lower two views show the same location a few days later after Hurricane Sandy. The dune is still largely intact and the fence undisturbed but the beach width and elevation has been significantly reduced. South of this site the beach is visibly narrower in the distance. 20

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23 SH-123, site 123 is located south of the development and just north of the terminal groin. This region has benefited tremendously since the completion of the initial ACOE 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 well into Hereford Inlet. However, like the other Borough beaches that received sand during the 2011 ACOE project this location suffered significant erosion of the dry beach berm during Hurricane Irene and the October 2011 Nor easter. By December 2011 the berm was nearly eliminated and retreated about 150 feet to the seaward dune toe. From December 2011 to June 2012 the shoreline advanced 12 feet as some sand moved back onshore under favorable conditions. Longshore drift moved more sand south resulting in a net profile sand volume loss of 13.20yds 3 /ft. during the first half of Over the summer months some sand continued to move onshore but the beach remained relatively narrow with a low elevation profile. The net change for the year prior to Sandy was a modest shoreline position seaward advance of 19 feet but a net profile volume loss of yds 3 /ft. of sand, as offshore losses to the south towards Hereford Inlet offset onshore gains. As Hurricane Sandy moved onshore storm waves scoured out the narrow beach reducing 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 yds 3 /ft. of sand from the storm. Photograph 8. The top views to the north taken on June, 2011 (left) and October 24, 2012 (right) at 123 rd Street shows the spring and fall dune and beach conditions. Sand has accumulated along the fence line near the seaward dune toe and the pilings used for catamaran slips are half buried. The beach is wide but the lower elevation profile is evident with the high water line approaching the catamaran slips. Both post Sandy photos show a severely eroded reduced beach width and elevation. Along the seaward dune slope waves cut a steep scarp back to the seaward crest.

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25 Summary The total net sand volume change from December 2011 to October 24, 2012, five days prior to Hurricane Sandy was a loss of 157,108 cubic yards of sand, eroded from the study area from 82 nd Street to 123 rd Street across the Stone Harbor oceanfront including the dunes, beaches and offshore seafloor. Taking a look at the year following construction of the 2011 USACE project shows Hurricane Irene and the October 2011 northeaster eroded and reduced the sand volumes placed by the USACE by 164,155 cubic yards but the project was successful in protecting homes and infrastructure within the Borough. This year s annual loss, before Hurricane Sandy, combined with the post-construction loss represents approximately 55% of the sand volume placed during the 2011 USACE project lost prior to the arrival of Sandy. 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 29.84yds 3 /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. Hurricane Irene, the October 2011 northeaster and Sandy have combined to remove 120% of the sand placed in 2011 during the USACE maintenance project, a total of nearly 702,000 cubic yards of sand from the beaches in less than a year and a half. The post Sandy survey did not extend seaward beyond the shoreline position and it is likely some sand deposited along shore parallel bars will move back onshore when conditions are favorable. However, past shoreline process trends of dominate sand transport through longshore drift strongly suggest much of this sand will be lost from the Borough s developed shoreline. Sand will likely be transferred south towards Hereford Inlet, resulting in the net long term loss of a significant percentage of sand eroded from the Borough s study area and project beaches and dunes during Sandy. Conclusion 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. A 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 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 1 st of any given year. The CRC has completed several surveys of 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. This year the point has extended south over 500 feet and is now over a mile long stretching 5,555 feet from the terminal groin south of 123 rd 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 ACOE 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. Recycling and reusing sand from South Pointe to maintain the erosional beaches to the north could both establish a more sustainable beach system and cost less. 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

26 could save money in the long term. Similar programs were initiated this year in neighboring Cape May County communities of Avalon and North Wildwood to help establish a more cost effective approach to 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 declaration for Hurricane Irene. Recommendations for 2011 and Beyond: 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 now 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. Recommendations as result of recent events have not changed significantly from previous reports. An emergency maintenance project cycle should be implemented with a minimal placement volume of 800,000 cubic yards placed as berm material and to restore the dune template seaward slope where needed. This is currently in preparation to undertake construction across the entire Townsend s Inlet to Hereford Inlet ACOE Shore Protection Project starting in December 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. It is recommended to load the deposition of maintenance sand strongly to the northern beaches, because sand tends to move south between groin cells fairly quickly. Following maintenance, fence along the lower third of the seaward slope (in a zigzag pattern) of the dune system immediately 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 New 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. 2