FINAL REPORT FOR 2013 ON THE CONDITION OF THE MUNICIPAL BEACHES IN THE TOWNSHIP OF UPPER, CAPE MAY COUNTY, NEW JERSEY

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1 FINAL REPORT FOR 2013 ON THE CONDITION OF THE MUNICIPAL BEACHES IN THE TOWNSHIP OF UPPER, CAPE MAY COUNTY, NEW JERSEY Aerial photograph at Corson s Inlet showing conditions on December 1, 2013 of the north end of Ludlam Island, inlet shoals and south Peck s Beach. The State Park beaches are expansive with a developing flood tidal shoal that extends off the western shoreline. Along the northern inlet shoreline the channel margin, north bypass and ebb shoals are well developed. As these shoals build the adjacent tidal channel is pushed south where tidal dynamics accelerate shoreline erosion on the adjacent beach. A hint of erosion to come is seen in the shoreline alignment at Seaview Avenue with a slight landward jog in the wet/dry line along the beachface and reduction in the dry beach width. (photo by Ted Kingston) PREPARED FOR: THE TOWNSHIP OF UPPER PO BOX 205 TUCKAHOE, NEW JERSEY PREPARED BY: THE RICHARD STOCKTON COASTAL RESEARCH CENTER 30 WILSON AVENUE PORT REPUBLIC, NJ JUNE 2014

2 TABLE OF CONTENTS Introduction 1 Engineered Beach Overview 1 Hurricane Sandy 2 Figure 1. Response to Hurricane Sandy 2 Impact from Winter Storm Saturn 3 Beach Monitoring Methodology 3 Figure 2-4. Corson s Inlet Aerial Photographs 5 Figure 5. Specific Profile Sites 8 Individual Site Review 8 Figure 6 a-c. Photos of Survey Line Figure 7. Line 36 Cross Sections 11 Figure 8 a-c. Photos of Survey Line Figure 9. Line 22 Cross Sections 14 Figure 10 a-c. Photos of Survey Line Figure 11. Line -02 Cross Sections 17 Figure 12 a-c. Photos of Survey Line Figure 13. Line -20 Cross Sections 20 Figure 14 a-c. Photos of Survey Line Figure 15. Line -46 Cross Sections 23 Geographical Information System Elevation and Sand Volume 24 Digital Elevation Map 24 Figure 16. Engineered Beach Elevation Change Map Figure 17. Engineered Beach Elevation Change Map 6/ / Corson s Inlet Borrow Zone Changes 27 Figure 18. Corson s Inlet Elevation Change Map Dec to July Figure 19. Corson s Inlet Elevation Change Map - Nov to Feb Figure 20. Corson s Inlet Borrow Zone Changes June Summary and Conclusions 31 i

3 Annual Report for 2013 To The Township of Upper On the Condition of the Municipal Beaches Introduction This annual report presents the status of the beaches within the Township of Upper for 2013 and recovery since Hurricane Sandy. Sandy made landfall near Atlantic City as a result the storm waves and surge caused extensive severe erosion along much of the Jersey shore, especially hard hit were the regions north of Atlantic City. Township of Upper was fortunate as the path put the Township on the weaker southern quadrant of the storm as it moved onshore where the surge and winds are reduced. Sandy still caused significant beach and dune erosion, flooding and damages to property and infrastructure but the Township was sparred the erosion, damages and destruction suffered in communities of Ocean County. The Township s engineered beach absorbed and attenuated the storm waves and surge along most of the engineered shoreline. However, the storm did produce extensive tidal surge flooding exceeding that seen December 1992 by 12 to 18 inches. As a result white water waves rolled across the flooded beach and washed into the dunes. Post storm surveys showed sand deposits at the seaward dune slope derived from the berm and beachface that had eroded and lowered in elevation 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 Upper Township erosion was modest in comparison with most sections of the engineered beach near the design template. Over the course of the last four years there has been five Presidential disaster declarations made for New Jersey s coast in response to three northeast storms and two hurricanes, starting with a strong nor easter November 11-13, 2009 to most recently Hurricane Sandy on October 29, Each of these presidential declarations has allowed the Township to be eligible for FEMA reimbursement under Category G losses to an engineered beach project to share the cost of sand replacement following each storm event. The Township of Upper (Township) oceanfront shoreline and nearshore bathymetry were surveyed by the Richard Stockton College of New Jersey Coastal Research Center (CRC) to document changes in shoreline position and volume from these storms and over the past year. This annual report presents a discussion of shoreline changes, Sandy recovery and performance of the engineered beach. Engineered Beach Overview To review, an initial beach nourishment project co-sponsored by the Township and the New Jersey Department of Environmental Protection (NJDEP) was completed in October 2001 that placed 461,000 cubic yards of sand on the beach. This initial project was followed by a more comprehensive joint project in August of The extent of the work ran from the municipal boundary at Corson s Inlet State Park (100 feet north of Seaview Avenue) and extended south to the boundary with Sea Isle City. A total of 688,000 cubic yards (CY) of sand was used to construct dunes and berm covering approximately 9,000 feet. Since completion of the 2009 project, there have been five Federal disaster declarations. The declarations include: November 2009 Northeast Storm (DR-NJ 1867); the March 2010 Northeast Storm (DR-NJ 1897); and a December 26, 2010 Northeast Storm (DR-NJ 1954). Following Hurricane Irene (DR-NJ 4021), there was yet another loss of 106,949 CY of sand from the Upper Township beaches. All individual disaster assessments were combined in 2011 and maintenance nourishment conducted in late fall of 2011 completed in winter

4 Weeks Marine Inc. was the contractor for the 2011 beach restoration project and utilize the Corson s Inlet borrow area as a sand source, work was scheduled to commence in November Sand was placed on the beach, surf zone and nearshore on northern Ludlam Island within the State Park and Township boundaries. In addition, sand was placed on the beach and nearshore at the Township s central and southern oceanfront from approximately Survey Line to the municipal boundary with Sea Isle City. The restoration project was completed in January The final reported project volumes within the design template as provided by Week s were 132,674 CY added to the northend Natural Area and 315,940 CY to the Township beaches. The CRC survey s showed a total of 590,916 CY of sand was added to the region, including changes occurring offshore beyond the project design template limits. Hurricane Sandy Hurricane Sandy made landfall near Atlantic City on October 29, 2012 in Upper Township the beach lost 172,763 CY of sand from within the engineered beach template. The State Park section lost an additional 64,109 CY of sand. The net loss for the entire project area was 236,873 CY of sand. Largest losses along the project beach were south of Prescott Avenue to the Sea Isle City border and at the north end focused around Seaview Avenue. As an engineered beach the project would again have been eligible for FEMA reimbursement under Category G losses to an engineered beach. Despite the erosion and loss of sand the engineered beach performed well absorbed and attenuated the wave and storm surge provided sufficient storm protection to prevent the catastrophic damages suffered in parts of Ocean County. The elevation change map below shows the erosion from Sandy in red. Figure 1 elevation change map above shows the impact of Hurricane Sandy on the engineered beach. The red colors show the areas of greatest elevation loss while green are areas of gain. The black outlined area delineates the Township s engineered beach. The greatest area of loss during Sandy was to the southern region and at the north end focused near Seaview Avenue. Sand transferred to the offshore bar system partially offset onshore and nearshore losses. 2

5 Impact from Winter Storm Saturn: Winter storm Saturn tracked up the east coast for several days from March 4-7, 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 moved north along the New Jersey coast and caused significant beach erosion along Cape May County and the Township s engineered beach. Storm waves generated during Saturn over washed and flattened the beach berm reduced the beach width and elevation and scoured the nearshore seafloor. The storm removed any sand that had naturally recovered on the beach following Sandy and slowed future natural beach building by scouring the nearshore and transferring sand further offshore. Longshore currents generated by the NE storm wave approach swept much of the eroded sand south away from the Township beaches especially along the south end. The combined impact of Sandy and Saturn stripped sand from the Township s beaches flattened the berm and moved sand away from the oceanfront shoreline within a 4-month period. A deeper trough was formed nearshore from storm wave scour while wave run up reached the dune system at the south end and eroded the seaward slope and developing foredunes. Long term natural recovery at the south end will be hampered by a limited sand supply within the system in this region. As a result the south end beaches will likely remain narrow and low in elevation for an extended period or until re-nourished, which will expose the narrow dune ridge to erosion and potential overwash or breach during future storm events. Beach Monitoring Program Methodology The beach monitoring program extends back to June 1995 when the Township of Upper requested that the Richard Stockton College of New Jersey Coastal Research Center (CRC) design and establish a means to provide information on coastal zone management issues within the municipality. Initially, six sites were selected to survey and allow calculations to provide information on beach behavior. In 2009, three additional beach profile stations (UT-21, UT-31, and UT-7) were established in sections that did not have profiles to monitor sediment movement within groin compartments and along Corson s Inlet. Data collected from these sites provided the criteria to determine the need and extent of re-nourishment required to help stabilize the Township s shoreline. In order to qualify the Upper Township beach as an engineered beach eligible for FEMA funding and provide survey data for potential disaster losses to the Federal Government, the decision was made in 2009 to discontinue the traditional sites and instead continue to monitor the 200-foot spaced baseline station cross sections used during construction of the 2009 Upper Township beach nourishment project to quantify sand volumes required and placed. The time interval between surveys was increased to six months from the quarterly interval previously to help control the costs of gathering the data. The data presented in this report evaluates the performance of the engineered beach over the 2012 to 2013 year. Each profile survey (cross section) includes the dunes, beach and nearshore to approximately -12 feet. The profile locations are spaced 200 feet apart along the inlet and oceanfront south to the Sea Isle City boundary with Strathmere. Because sand volume changes often occur further seaward than effectively reached by swimming from shore, a vessel was used to survey the outermost 1,500 feet of each cross section at the same time the land and wading work occurred. The vessel employs RTK-GPS technology linked to a digital depth recorder through Hypack software to generate data along the traverse line with a tidally-corrected NAVD88 elevation and NAD 83 horizontal control NJ State Plane Coordinate value for each point. All the data was transferred to Arc GIS software and a series of Digital Elevation Models are built and superimposed on the latest available digital aerial imagery to show the 3

6 scope and nature of the changes recorded between surveys. In addition cross-sectional plots were provided to show two dimensional changes to the dune, beach and nearshore at select sites along the engineered beach that best represent regional changes in those areas. The following is a list of the surveys that are included in this report and the dates they were completed: Survey 16 October 22, 2012 (pre-sandy) Survey 17 November 02, 2012 (post-sandy) Survey 18 June 10, 2013 Survey 19 November 25, 2013 Note that the October 2012 survey was completed just days prior to the Hurricane Sandy making landfall on the Jersey coast on October 29, The relatively continuous gathering of the topographic and bathymetric survey data along the Township s shoreline allows the CRC to present discrete views of significant regions of change that may require immediate attention. The major source of the problems during the past eight years has been rapid, erosional changes to the inlet and northern oceanfront shoreline. Focus should remain on the northeast corner of the island at Seaview Avenue, where over the past 8 months this has been a region of severe erosion. Following Sandy the deteriorated section of the southern beaches south of Prescott Avenue to the Sea Isle City border will also require maintenance attention. The inclusion of oblique, hand-held aerial photography flown by local pilot and resident of Strathmere, Mr. Ted Kingston provides a unique perspective for identifying visually the changes quantified by the survey data. Mr. Kingston s photographs are included in this report as the cover photograph and in Figures 1, 2 & 3 that show the inlet and northern ocean beach configuration seasonally throughout the past year. In reviewing this series it is evident that starting in the fall erosional processes began to dominate the changes affecting the northend configuration, the erosion accelerates with winter storm events shown in the final photo taken January 31, The survey data presented in the inlet elevation change maps in figures 18 & 19 later in this report quantify the dynamic channel changes occurring in the inlet that influenced the accelerated beach erosion seen in the photo series below (Aug. 2013, Nov & Jan. 2014). 4

7 Figure 2. Aerial photograph showing Corson s Inlet State Park and the Upper Township beaches on August 8, Note the wide oceanfront and inlet beaches, no groins or bulkhead structures are visible still buried below the wider beaches. (photo Ted Kingston) 5

8 Figure 3. A similar aerial photograph perspective showing Corson s Inlet State Park and the Upper Township beaches on November 29, Inlet beaches are still wide even at high tide. There is evidence of the formation of an erosional beach berm scarp along the ocean shoreline seaward of Seaview Avenue near the high water wrack line. The scarp starts near Seacliff Avenue and continues north through the park boundary. No timber groins or other relic structures are yet exposed still buried below the current beach configuration. (photo Ted Kingston) 6

9 Figure 4. A similar aerial photograph perspective again showing Corson s Inlet State Park and the north end of Ludlum Island on January 31, 2014 following a winter storm that blanket the region in snow. Storm waves severely eroded the beachface all along the Township s oceanfront that exposed relic timber groins and rock groins previously buried below the project beaches. Note the nearshore scour trough cut between the beach and shoal visually evident at low tide. As it expands and develops this feature will channel tidal currents along the beach potentially cause additional scouring nearshore and sweep sand away from the region with the inlet tidal flow. On the bayside the flood tidal shoal development is impressive as sand continues to move inshore along the inlet shoreline. (photo Ted Kingston) 7

10 Specific Profile Site Descriptions Figure 5 located below shows the locations of all 58 beach profile stations on the inlet and ocean coast. Five sites are selected (in red 36+00, 22+00, 02+00, and ) to show changes in the beach throughout 2013, photographs and cross sections are presented later in this report. Figure 5. Locations of all foot spaced beach profile stations for the engineered beach in Upper Township. The map includes both the Township and Corson s State Park project areas and the respective monitoring locations. Shoreline conditions at select representative locations highlighted in red are described in the following pages. Individual Site Review: This section describes the shoreline and volume changes documented at selected profile locations to show general trends in sediment movement along the Township s engineered beaches for Beach volume and shoreline changes were calculated from November 2012 to November Profile plots included show survey results from October 22, 2012 just prior to Sandy, November 2012 following Sandy June 2013 and November Photos for each site are included to show the beach conditions following winter storm Saturn and during the two surveys in

11 Survey Line located near Seaview Avenue This ocean-front profile station is located on the northeast corner of the island this region has been the focus point of erosion along the Township s engineered beach. Following construction of the engineered beach in 2009 the dune remained relatively stable but the beach was subject to episodes of storm related erosion. Prior to initial construction, inlet dynamics and wave erosion eliminated the State Park beach along the inlet and cut into the Township beach near Seaview Avenue back to private oceanfront properties prompting emergency installation of a steel sheet bulkhead. This was later reinforced with a rock revetment to stabilize the bulkhead and prevent further scouring of sand along the base of the steel sheets. The 2009 beach nourishment restored the dune and beach along the Township shoreline and State Park. Following several severe northeast storms and Hurricane Irene the Township and State conducted a maintenance nourishment project in late 2011 through early 2012 to return the engineered beach to its design dune and beach template. When Hurricane Sandy struck the New Jersey coast on October 29, 2012 the dry recreational beach berm width extended seaward from the seaward dune toe by 250 feet. Because of the angle of approach and path of the storm this region fared well compared to other beaches in New Jersey devastated by Sandy. The storm waves and surge eroded the berm and reduced the elevation of the seaward half of the beach. Sand was pushed landward onto the dune or dragged to the nearshore where the flattened berm and sand deposited nearshore advanced the beachface and shoreline position seaward 60 feet. Offshore the wider shoal extended seaward over 500 feet. By June 2013 following northeast storm Saturn and the winter wave climate the beachface had eroded landward 60 feet. A trough was scoured nearshore and the offshore shoal diminished. The fall wave climate and tidal currents accelerated the erosion rate and by November 2013 nearly two thirds of the recreational beach berm present prior to Sandy was gone, the shoreline position had retreated 215 feet. A deeper trough was scoured nearshore and the offshore shoal reduced and flattened. The water depth in the shoal region was 3 to 4 feet deeper. Offshore volume losses associated with just the scour trough and shoal reduction was yds 3 /ft. of sand. An additional yds 3 /ft. of sand eroded onshore for a net loss of yds 3 /ft. of sand From November 2012 to November 2013 at Seaview Avenue. The loss of the well-developed ebb shoal reduced the wave shelter effect afforded this beach previously by the shoals exposing the beach to northeast wave approach. The rapid rate of erosion will continue as the nearshore trough now forms a tidal channel that extends from the State Park Inlet shoreline to Whitter Avenue and allows tidal currents to rapidly move sand from the region. 9

12 6a. March 7, b. June 24, 2013 Figures 6a to 6c. Survey line near Seaview Avenue. View to the north. Photograph 6a shows the beach conditions following winter storm Saturn a northeast storm that impacted the coast on March 5, The storm surge and wave run up reached the seaward dune toe evident by the wet dry line in the sand. Photograph 6b shows that the fenced off exclusion area for nesting shorebirds extends well onto the beach. This region is an important habitat for nesting shorebirds. Severe erosion prior to 2009 had previously threatened the stability of this habitat. Photograph 6c was taken on November 14, 2013 following summer accretion. Within weeks erosion cut a beach scarp along the berm near Seaview Avenue (see figure 4). 6c. November 14,

13 Figure 7. Hurricane Sandy and winter storm Saturn combined eroded the beach face and berm. Some sand was pushed higher up the beach deposited across the upper beach onto the seaward dune slope. The fall wave climate and changes to the inlet channel accelerated beach erosion, by November 2013 half the beach berm present a year earlier had eroded. As disturbing was the reduction in the offshore shoal and a deeper trough cut nearshore that increased the impact of tidal currents along the shoreline. For the year from November 2012 to November 2013 the shoreline position retreated 215 feet with a loss of yds 3 /ft. of sand 75% was from the offshore shoal and nearshore as the waves and tidal currents scoured the seafloor. 11

14 Survey Line 22+00, Whittier Avenue, Strathmere In the past, this profile location has demonstrated an accretive trend due to beach fill activities and natural patterns of sand migration. Northeast storms and ebb tidal flow moves sand from the inlet shoals, south, depositing the majority of sand between Williams and Tecumseh with a gradual taper further south to approximately Prescott Avenue. Little to no sand was added directly to this region during the 2009 beach restoration project or needed in the 2011 maintenance project. The width of the dry recreational beach berm here extended seaward from the dune toe by 300 feet when Hurricane Sandy struck the New Jersey coast on October 29, Again because of the angle of approach and path of the storm this region fared well compared to other beaches in New Jersey devastated by Sandy. The storm waves and surge eroded the berm and reduced the nearshore elevation. Sand was carried offshore where a shore parallel bar formed. Despite the modest berm erosion the beachface and shoreline position advanced seaward 20 feet and the upper beach near the seaward dune toe gained sand adding up to a foot of elevation along the toe. The beachface was flattened and sand eroded from the lower berm dragged to the nearshore forming a shallow platform along the shoreline following Saturn and the winter wave climate seen in the June 2013 profile. Offshore the sand bar was diminished as sand moved onshore and away from the profile. The fall wave climate caused additional erosion and by November 2013 a deep trough was scoured nearshore the beachface flattened and the shoreline position retreated. Sand was carried cross-shore where a shore parallel bar reformed in nearly the identical position following Sandy. As a result this region loss a net yds 3 /ft. of sand for the year, over 64 yds 3 /ft. of sand was from the nearshore where the new trough formed. Onshore sand volume losses (3.83yds 3 /ft.) from the berm and beachface were minimal offset by sand gained on the dune system and upper beach. The development of the nearshore trough that extends south from the inlet creates a nearshore channel for the inlet ebb tidal flow along the shoreline from the State Park exiting in this region. 12

15 8a. March 7, b. June 24, 2013 Figures 8a to 8c. Survey line located between Whittier and Tecumseh Avenues. View to the south. All photographs show the wider beach typical of this region. Figure 8a taken immediately following winter storm Saturn the photo shows the storm waves and surge pushed the debris wrack line midway up the beach. Figure 8b the wide beach remains an excellent source of aeolian sand transport to the developing dune system. Figure 8c shows sand continued to accumulate on the upper beach and dune toe. This section of the Township s engineered beach remained relatively stable onshore through c. November 15,

16 Figure 9. Hurricane Sandy s waves eroded the berm but the storm s surge and winds pushed sand higher up the beach adding sand to the seaward dune slope and foredune. The early fall wave climate scoured the berm, beachface and nearshore forming a deep nearshore trough and offshore shore parallel bar system. The annual net volume change from November 2012 to November 2013 was a loss of 68.41yds 3 /ft. of sand focused on the beachface and nearshore wave scouring, the shoreline position retreated 79 feet. 14

17 Survey Line 02+00, Prescott Terrace, Strathmere; This profile location is positioned near the only recreational vehicle park on the ocean beaches of New Jersey in the Township s central oceanfront section. There is a continuous dune adjacent to the beach that runs along Commonwealth Avenue approximately 100 feet wide with a crest elevation of feet NAVD88. The 2009 beach nourishment added a 100-foot wide dry beach berm here seaward of the dune. This beach has provided a source of aeolian sand that has feed development of a foredune ridge at the seaward toe. This section of the engineered beach has remained relatively stable during recent storm events since initial construction. The 2011 project taper for the south end began in this region and required only a modest sand volume added to restore the design template. Prior to Hurricane Sandy the beachface and beach berm extended nearly 300 feet seaward of the dune. Following Sandy the berm crest and beachface slope was flattened but the shoreline position was stable as sand was carried nearshore forming a shallow platform along the shoreline. Sand was pushed higher up the beach to the seaward dune slope and upper beach additional sand was deposited offshore forming a shore parallel bar. As a result the net sand volume loss was limited as again the Upper Township shoreline fared much better than much of the jersey shore during Sandy. Winter storm Saturn and the winter wave climate caused additional erosion and by June 2013 the nearshore was scoured and the beachface and berm flattened pushing the shoreline position over 100 feet landward. Storm surge and waves also removed sand from the upper beach and along the seaward dune toe. Offshore the bar formation diminished as sand was swept from the region by waves and longshore currents. Over the summer cross-shore transport moved the remaining sand from offshore landward a thin veneer of sand was added from the toe of the beachface slope to the berm crest. By November 2013 the beach berm still 200 feet wide provided ample storm protection and source of aeolian sand for continued foredune development. The net change from November 2012 to November 2013 was a loss of yds 3 /ft. of sand again derived mostly from loss of the offshore bar and nearshore wave scouring. Losses nearshore along the beachface caused the shoreline position to retreat 95 feet in

18 Figure 10a. June 5, 2013 Figure 10b. June 5, 2013 Figure 10a and 10b taken looking north. Figure 10a shows aeolian sand has accumulated along the seaward dune toe and plants have colonized the region a new foredune feature has developed. Figure 10b shows the extent of the wide beach at the same location on the same day. The wide beach provides an excellent source of aeolian sand to continue development of the new foredune here. 16

19 Figure 11. During Hurricane Sandy the beach berm was eroded and flattened but sand was pushed higher up the beach where it added to the developing foredune. Winter storm Saturn and the winter wave climate eroded the beachface and nearshore slope. The offshore bar dissipated as sand was redistributed during the remainder of the year. For the year the site lost yds 3 /ft. of sand primarily from offshore while nearshore wave scour cut into the shoreline position and caused a net retreat of 95 feet. 17

20 Survey Line , 1200 feet South of the RV Park, Strathmere; This profile station is located in the central section of the Township s oceanfront. In the mid 1980 s the State shared in the construction of three timber and rock toe groins in this reach in an attempt to slow the loss of sand south. The groins are located at survey lines , and on the site location map (Figure 2). The beaches were low and narrow with the dune essentially the only protection for the road and homes west of the highway. Further south in Sea Isle City, storm activity produced breaching and overwash again and again starting in 1984, continuing in 1991, 1992, 1994 and After the 1998 events, the dune was re-built with a geo-textile core and quarry sand was piled on top to generate a tougher barrier. In 2009 this region was addressed during the beach restoration project expanding the dune and building a wider beach berm to prevent further overwash and protect shorefront homes and infrastructure from repeat damages. The region fared well during Hurricane Sandy compared to Ocean and Monmouth County beaches. Here again erosion was limited to the beachface and beach berm the dune system remained intact. Waves and storm surge flattend the beachface slope and berm here the elevation was reduced across the entire 200 foot-wide beach berm and increased onshore losses compared to the previous sites. The shoreline position remained relatively stable as sand was dragged to the nearshore and offshore where a shore parallel bar formed. No sand was added to the dune system. By the spring 2013 survey the beach had seen modest recovery onshore as the weather and wave climate became favorable for natural beach building processes to push sand higher up the beachface slope to form a berm ridge. Landward cross-shore transport moved sand from the offshore bar closer to the beach. The bar continued to move landward over the summer and by the fall survey it had moved nearly 200 feet landward from its November 2012 position still separated from the beach by a nearshore trough. No additional sand was added to the beach but aeolian sand was deposited across the seaward dune slope. The net change for 2013 was a modest volume loss of yds 3 /ft. of sand as the shoreline position retreated 25 feet landward. As with the sites to the north the majority of the sand was lost from offshore and nearshore from November 2012 to November

21 12a. March 7, b. June 6, 2013 Figures 12a to 12c at Line at the Southern Strathmere Beach. View to the south. Photograph 12a shows the Post winter storm Saturn conditions. Combined with damages suffered during Hurricane Sandy the beach was flattened and the dune toe fence damaged. The wrack line shows higher tides have recently reached the seaward dune toe. Photograph 12b by late spring new dune fence was installed and natural recovery has moved sand onshore elevated the beach and provided a dry recreational beach. Photograph 12c taken in November the beach having accumulated sand over the summer appears to have remained relatively stable during the fall. 12c. November 21,

22 Figure 13. Hurricane Sandy eroded the beach flattened the beach berm and transferred sand cross-shore to the offshore bar. The dune system remained relatively stable to slightly accretive this year. Winter storm Saturn and Hurricane Sandy removed a small foredune but by November more aeolian sand accumulated on the seaward slope. During the spring and summer a modest volume of sand moved onshore and pushed higher up the beach. The offshore bar moved cross-shore towards the beach moving a large wedge of sand 200 feet closer to the beach. From November 2012 to November 2013 the net volume change was a loss of yds 3 /ft. of sand mostly offshore and nearshore, in response the shoreline retreated 25 feet. 20

23 Survey Line , Southern Strathmere Beach (Taylor Avenue) This profile station is located in the southern section of the Township s oceanfront shoreline just north of the Township border at the third and final rock groin on the Strathmere beach. As discussed for survey line this section of shoreline prior to the 2009 project was a region subject to frequent storm overwash and extensive dune erosion due to narrow low profile beaches and a narrow dune. In 2009 this region was also addressed during the beach restoration project again expanding the dune and building a wider beach berm to prevent further overwash and protect shorefront homes and infrastructure from repeat damages. This section was hit hardest during Hurricane Sandy the beachface and berm were flattened to the seaward dune toe where wave run up scoured the seaward slope and pushed the seaward slope 20 feet landward. The elevation of the beach was reduced up to 3 feet significantly reducing the overall sand volume and storm protection afforded the dune in future events. A deeper nearshore scour trough developed and some sand was deposited on an offshore bar. Some sand was carried cross-shore to the offshore bar. Little or no sand was added updrift on the Township beaches so the majority of eroded sand appears to have been swept away from the site to the south or transferred well offshore beyond the survey limits. The June 2013 survey showed only modest changes onshore. Modest wave scour occurred along the shoreline position while offshore cross-shore transport moved sand landward partially filling the nearshore trough. The fall wave climate was less favorable as the trough deepened with only a modest volume of sand added to the shoreline. From November 2012 to November 2013 there was little change onshore no sand was added to the beach. Offshore sand movement was limited to between the bar and trough. The net volume change from November 2012 to November 2013 reflected this relatively limited movement of sand with a net change of just 3.07 yds 3 /ft. of sand. Shoreline position was relatively stable with just 12 feet of landward retreat. Located near the southend of the project area there is a limited volume of sand available in this region to initiate significant natural recovery in the immediate future. As a result the narrower and lower beach now well below the design template will not be as resilient to future storm events. In the current condition and configuration this section of shoreline will be exposed to dune erosion and potential overwash during a severe storm event. The lower and narrow elevation beach would likely be submerged by a severe storm surge and storm waves would directly impact the dune system. With a 25- foot narrow crest at elevation 12.5 feet NAVD88 the dune would not absorb prolonged storm wave impact before potentially being overtopped or possibly breached. During Hurricane Sandy oceanfront communities with wider beaches suffered significantly fewer dune breaches and overwash. By comparison communities with narrow beaches were most vulnerable to storm wave overwash and dune failures during Sandy. 21

24 14a. March 7, b. June 6, 2013 Figures 14a to 14c at Line , Taylor Avenue, Strathmere. View to the north. Photograph 14a. Photo shows conditions following winter storm Saturn. The beach is further flattened and eroded by Saturn following Hurricane Sandy. Damaged dune fence indicates the extent of wave run up and erosion on the seaward slope during the storms. Photograph 14b. Dune fence has been replaced and aeolian sand has been added to the seaward slope. Modest sand recovery has created a narrow dry beach seaward of the fence. 14c. November, 25, 2013 Photograph 14c. Following the typical summer beach building pattern sand has pushed up onto the upper beach forming a wider dry beach seaward of the dune system. The dry beach is double the width seen in June, 2013 but the appearance is deceptive as the beach elevation is less than 4-5 feet NAVD88. As a result most of the beach is barely above a normal high tide range. It remains marginal for absorbing and attenuating storm waves or protecting the dune from direct wave assault during a future severe storm where the beach is submerged by the surge. 22

25 Figure 15. Hurricane Sandy caused significant beach erosion and flattened the berm present in the October 22, 2012 survey with erosional losses continuing landward onto the seaward dune slope. A deeper nearshore trough was scoured and some sand transferred cross-shore to the offshore bar. For 2013 the beach remained relatively stable, some sand was added to the dune slope and crest while sand offshore slowly moved landward. By November a thin veneer of sand accumulated onshore that raised the upper beach elevation to 4-5 feet NAVD88 just above the high tide range. The net volume change from November 2012 to November 2013 was a modest of 3.07 yds 3 /ft. of sand with 12 feet of retreat in the shoreline position. The project berm elevation and width eroded during Sandy has not recovered naturally in 2013 the current beach is below design template, lower in elevation and width. The dune is vulnerable to storm waves and surge. 23

26 Geographical Information System Elevation & Sand Volume Data collected by the CRC s beach survey team (elevations of the dune, beach, and nearshore) and the CRC s research vessel team (bathymetric data beyond the range of the swimmers to a depth of approximately -20 feet) was integrated into a geographical information system (ESRI ArcGIS) software Digital elevation modeling was used to compute changes in elevation and sand volume for the Township s beaches and nearshore areas. The ArcGIS software incorporates all the elevation data points, defines triangular areas among groups of three near-by points, and lastly establishes change in elevation (the vertical difference between the two surfaces being compared). These vertical measurements were converted into a specific area (square feet). Then, the resulting volume is divided by 27 cubic feet per cubic yard to get a volume comparison difference. Each zone, block, region or area of the beach can be defined to arrive at a volume change or elevation difference desired by the operator. The data density was set at cross sections every 200 feet along both the inlet and oceanfront shorelines. Digital Elevation Maps The maps provided in figures 16 & 17 below shows the annual elevation changes between November 2012 and November 2013 and the seasonal changes between June 2013 and November 2013 for the dune, beach, and nearshore/offshore areas. Each color classification represents a two-foot elevation change. Positive elevation changes (green hues) indicate sediment gain. Negative elevation changes (orange-red hues) indicate sediment loss. Yellow areas are zones of no change. The maps show the inlet and northern beaches suffered the greatest losses of sediment during the time period (post-sandy). The offshore region near the Township s mid-section (Whittier Avenue) also lost sediment. Modest gains were found onshore along the Township s mid and south sections as some sand moved onshore and on the State Park s western shoreline where sand was pushed inland towards the flood tidal shoal. The northeast facing corner of the engineered beach in the State Park and near Seaview Avenue continued to be the erosional hotspot. Annual Volume calculations that compare the surface elevation changes between surveys showed a total net loss of 469,900 cubic yards (CY) of sand during the time frame November 2012 to November Breaking the losses down between project regions showed 187,000 CY was lost from the State Park while 282,900 cy eroded from the Township beaches. These losses alone not including erosion suffered during Sandy removed 140% of the 132,674 CY of sand added to the State Park during the 2011 project and 89% of the 315,940 CY of sand placed along the Township shoreline. 24

27 Figure 16. The elevation change map above for November 2012 to November 2013 sows elevation and volume changes on the beach, nearshore and offshore (to approximately -20 feet NAVD88) in Upper Township. Red colors show areas of elevation loss while green regions are elevation gains. Annual Volume calculations that compare the surface elevation changes between surveys showed a total net loss of 469,900 cubic yards (cy) of sand during the time frame. Breaking the losses down between project regions showed 187,000 cy was lost from the State Park while 282,900 cy eroded from the Township beaches. Greatest losses were focused on the nearshore towards the north end of the project area. 25

28 Figure 17. The elevation change map above for June 2013 to November 2013 shows elevation and volume changes on the beach, nearshore and offshore (to approximately -20 feet NAVD88) in Upper Township. Red colors show areas of elevation loss while green regions are elevation gains. Volume calculations that compare the surface elevation changes between surveys showed a total net loss of 122,200 cubic yards (cy) of sand during the time frame. Breaking the losses down between project regions showed 34,100 cy was lost from the State Park while 88,100 cy eroded from the Township beaches. Greatest losses were again focused on the nearshore towards the north end of the project area. 26

29 Corson s Inlet and Borrow Zone Changes As part of the continuing monitoring program for the Township and State the CRC has conducted biannual surveys of Corson s Inlet. The surveys include the borrow zone, adjacent shorelines, shoals and tidal channel. Data collected by the CRC s beach survey team (elevations of the dune, beach, and nearshore) and the CRC s research vessel team (bathymetric data beyond the range of the swimmers to a depth of approximately -20 feet) was integrated into a geographical information system (ESRI ArcGIS) software Digital elevation modeling was used to compute changes in elevation and sand volume for the Township s beaches and nearshore areas. The ArcGIS software incorporates all the elevation data points, defines triangular areas among groups of three near-by points, and lastly establishes change in elevation (the vertical difference between the two surfaces being compared). Digital Elevation Maps The maps provided in figures 18 & 19 below shows the elevation changes between December 2012 and July 2013 and the changes between November 2013 and February 2014 for the dune, beach, and nearshore/offshore areas. Each color classification represents a two-foot elevation change. Positive elevation changes (green hues) indicate sediment gain. Negative elevation changes (orange-red hues) indicate sediment loss. Yellow areas are zones of no change. The December 2012 to July 2013 map (figure 18) shows infilling of sand into the borrow zone and main inlet tidal channel. Sand likely was derived from the bar and shoals off Peck s beach where the elevation decreased during the same time frame. Strong NE waves and longshore currents sweep sand south from the Ocean City Federal and State project beaches to this region. The influx of sand to the shoals eventually forces the orientation of the channel south towards the Strathmere shoreline. By July 2013 the nearshore has deepened significantly along the Strathmere inlet and oceanfront shoreline forming a new trough that allowed tidal currents to flow closer to the beach. The November 2013 to February 2014 map (figure 19) shows the process has continued. Infilling continued in the borrow zone filling the old tidal channel and 2011 dredge cuts that reduced flow while the ebb shoal expanded across the mouth of the inlet. The continued influx of sand has pressed the recently formed nearshore trough even closer to the beach. By February 2014 the trough was immediately adjacent to the shoreline and continuous from the State Park inlet shoreline south to where it exited near Vincent Avenue. This deep trough cut nearshore allows tidal currents to sweep along the beach and accelerate erosion in the region around Seaview Avenue. All the sand moving onto the outer and northern ebb shoals has sufficiently recharged the borrow zone for future projects. In just the 4 months between November 2013 and February 2014 survey the three borrow zones gained a net 330,350 cubic yards of sand. The final map (figure 20) shows the available sand in the Corsons Inlet borrow zones as of June A net 2.74 million cubic yards of sand is available in the defined borrow zones above the approved dredging depth. Of those 977,000 cubic yards is located in area C1B this region has been excluded from use in previous projects due to the proximity of the area to the Strathmere shoreline and inclusion of two shipwreck exclusion zones. As a result million cubic yards remains available for use in future projects within the previously used borrow zones in Corson s Inlet as of June This number continues to grow with the influx of sand off Peck s Beach as seen above between November 2013 to February 2014 an additional 330,350 cubic yards of sand accumulated in the borrow zones. 27

30 Figure 18. The elevation change map above for December 2012 to July 2013 shows elevation changes on the beach, nearshore and offshore at Corson s Inlet. Red colors show areas of elevation loss while green regions are elevation gains. The map clearly shows a recharge of sand within the defined borrow zone. While the borrow zone filled with sand the main inlet tidal channel also became shallower. A disturbing deepening towards the south may signal formation of a second channel closer to the Upper Township shoreline. 28

31 Figure 19. The elevation change map above for November 2013 to February 2014 again shows elevation changes on the beach, nearshore and offshore at Corson s Inlet. Red colors show areas of elevation loss while green regions are elevation gains. The map clearly shows a massive loss in elevation nearshore and along the southern inlet shoreline that continues along the Township beaches. Development of a tidal channel nearshore in this region will intensify erosion as the tidal currents sweep sand away from the beach. In general the borrow zone continued to gain sand as sand continued to infill from the north with a pocket of erosion near the western end of the region. During this three month interval the two approved borrow zones (C1_A & C1_Ex) gained 230,910 cy of sand. 29

32 Figure 20. The above map shows the available sand within the defined borrow zones as of June Green hues show regions of elevation gains in this case red is at or slightly above allowable dredging depths defined for each zone as shown above. The analysis shows there is 2.74 million cubic yards of sand available within the four defined borrow zone regions as of June An additional 330,350 cy of sand moved into the defined borrow zones from November 2013 to February 2014 bringing the total volume of sand available for future projects to over 3 million cubic yards. 30

33 Summary & Conclusions The most recent maintenance project for the Township s engineered beach in January 2012 restored the design template and placed 590,916 cubic yards CY (CRC) of sand on the project beaches. Week s Marine placed a reported 132,674 CY of sand on the northend Natural Area and 315,940 CY of sand on the Township beaches. In the following two years all of that material has been removed. There have been several events that caused this severe erosion of the Township s engineered beach. Hurricane Sandy made landfall near Atlantic City on October 29, 2012 in Upper Township the beach lost 172,763 CY of sand from within the engineered beach template. The State Park section lost an additional 64,109 CY of sand. The net loss for the entire project area was 236,873 CY of sand. Regions hardest hit during Sandy was the southern section south of Prescott Avenues and towards the inlet near Seaview Avenue. Winter storm Saturn struck the Jersey shore five months after Sandy. The storm further eroded beaches still recovering from Hurricane Sandy. Beachface slopes were flattened wave run up reached the seaward dune slope especially along the southern beaches and the nearshore scoured by wave action. Eroded sand was carried further offshore or swept south towards Sea Isle City along the south end or pushed inland along the inlet shoreline towards the flood tidal shoals. From November 2012 to November 2013 the shoreline suffered a loss of 282,900 CY of sand in addition to Sandy s losses. The annual volume calculations showed a total net loss of 469,900 CY of sand during the time frame November 2012 (post-sandy) to November By project region 187,000 CY of sand was lost from the State Park while 282,900 CY eroded from the Township beaches. These losses alone not including erosion suffered during Sandy removed 140% of the 132,674 CY of sand added to the State Park during the 2011 project and 89% of the 315,940 CY of sand placed along the Township shoreline. Erosion will continue to accelerate as the inlet maps clearly show development of a deep trough nearshore from the State Park inlet shoreline to Vincent Avenue that allows accelerated channel tidal flow along the beach. With continued sand influx into the Corson s inlet north channel margin and ebb shoals pressuring tidal flow south this new nearshore channel will likely continue to scour deeper and widen taking more of the northeast corner of the Township and State Park shorelines. The Corson Inlet borrow zones continue to be recharged by the influx of sand into the ebb shoal system. Over 2.74 million CY of sand was added to the defined zones by June Of that million CY was within the previously approved and used borrow zones above the allowed dredging depth for each zone. The data shows that as of June 2013 there was ample sand to perform another beach nourishment maintenance project using the same defined borrow zones. An additional 330,000 CY was added to the borrow zone over the winter of The following observations were made for 2012 to 2013: The engineered beach again performed as designed during Hurricane Sandy and winter storm Saturn. The wider beaches and dune system absorbed most of the storm energy and attenuated the waves and surge from overwashing the beach and breaching the dune system. Thereby protecting the oceanfront properties and infrastructure from major damages suffered in other Jersey coastal communities. The beach took the brunt of these storms and when combined with subsequent erosion suffered during 2013 removed the entire half million cubic yards of sand placed during the 2011/