2013 ANNUAL REPORT - TO THE CITY OF NORTH WILDWOOD ON THE CONDITION OF THE CITY BEACHES

Transcription

1 2013 ANNUAL REPORT - TO THE CITY OF NORTH WILDWOOD ON THE CONDITION OF THE CITY BEACHES View on June 18, 2013 from the 2 nd Avenue jetty looking south while the 2013 beach nourishment project was under way. Inlet tidal currents and ocean wave climate during the project rapidly cut into the beach berm leaving a scarp 2-3 feet high in the beach from 2 nd Street through 4 th Street. The contractor, Norfolk Dredging, replaced some of this eroded sand prior to demobilizing at the end of the project. PREPARED FOR: THE CITY OF NORTH WILDWOOD 901 ATLANTIC AVENUE NORTH WILDWOOD, NJ PREPARED BY: THE RICHARD STOCKTON COASTAL RESEARCH CENTER 30 WILSON AVENUE PORT REPBULIC, NJ APRIL 2013

2 TABLE OF CONTENTS Introduction Engineered Beach Performance 1 Engineered Beach History 2 Oceanfront Beach Surveys 3 Figure 1 Location Map of six of the 54 profile stations 3 Figure 2 Digital Elevation Model 2013 post-nourishment 4 Figure 3 Digital Elevation Model 2013 five months post-nourishment 5 Figure 4 Digital Elevation Model 2013 annual change 6 Individual Site Reviews 7 Figures 4-8 Site photograph and cross sections 7 Figures 9-11 Site photograph and cross sections 11 Figures Site photograph and cross sections 14 Figures Site photograph and cross sections 16 Figures Site photograph and cross sections 18 Figures Site photograph and cross sections 21 Summary 24 i

3 2013 ANNUAL REPORT - TO THE CITY OF NORTH WILDWOOD ON THE CONDITION OF THE CITY BEACHES Introduction: This annual report presents the status of the beaches within the City of North Wildwood for 2013 and recovery since Hurricane Sandy eroded the beaches for a net loss of 153,000 cubic yards of sand from the municipal beaches during the storm. 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. North Wildwood was fortunate as the path put the City 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 and damages to property and infrastructure but the City was sparred damages and destruction suffered in communities of Ocean County. The City 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 retreated between 75 and 125 feet during the storm. The north end beach was eroded landward to the revetment sea wall. Waves overwashed the top into Kennedy Boulevard. To the south the dune and beach seaward of the piers were eroded and water swept into the City streets across the beach. The piers survived, but the shoreline had retreated to the seaward ends of the piers at high tide. 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 North Wildwood those efforts included a beach nourishment maintenance project to restore the engineered project beaches. 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 City 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. Norfolk Dredging commenced beach nourishment efforts on June 12, 2013 and by July 2, 2013 had placed 150,530 cubic yards of sand in North Wildwood to restore the erosion caused by Sandy. In addition, natural recovery added to the placed sand totaling an amount of 283,285 cubic yards or 132,755 cubic yards of sand returned to the beach naturally above the placed volume. This past year was dominated by relatively calm weather and seas from December, 2012 to October 2013 with the exception of winter Storm Saturn that impacted the Jersey coast on March 5-6 but caused only modest beach erosion in North Wildwood. On October 10, hours of persistent 30 knot plus onshore winds generated storm waves that caused erosion along the Cape May County shoreline. Despite the erosion from these small storm events the 2013 beach maintenance project finished by July 2, 2013 helped to partially stabilize the erosional shorelines seaward of the south end piers and along the north end beaches near Hereford Inlet following Hurricane Sandy Engineered Beach Performance: Norfolk Dredging commenced beach filling June 12, 2013 and by July 2, 2013 had placed 150,530 cubic yards at the south end and north end of the North Wildwood engineered beach. The region in between was at or above design template and required no action to restore. In addition, natural recovery added to the placed sand totaling an amount of 283,285 cubic yards to the beach and the dunes. This means that the North Wildwood 1

4 engineered beach recovered over half the 519,853 cubic yards of sand lost since Irene from the 2009 design template that was created originally. The placement of sand plus the natural recovery has brought the beach back to just 236,578 cubic yards below the 1.4 million cubic yard initial sand volume placed in 2009 (83.1% of the initial fill). Much of this reduced volume is related to limits placed on the initial project beach extents. Regulatory agencies have curtailed further work along the Hereford Inlet portion of the initial project for endangered and threatened species reasons, plus the City of Wildwood had requested that the project end at some762 feet less than the original project extent. This reduction in project extent reduced the sand quantity necessary to restore the full design template. Therefore, the re-defined North Wildwood beach project appeared to be near its revised design template as a result of both natural recovery and the sand placement volume calculated to restore the direct impacts of Hurricane Sandy. Unfortunately rapid erosion occurred during the fall likely related to the 72 hours of onshore winds in October. By November the beach berm widths and elevations were dramatically reduced and the seaward dune slope exposed to wave run up in the recent project areas. At the northend waves cut into the dune slope along the seaward dune toe leaving a modest scarp. In front of the southern piers a similar trend occurred that intensified north to south. At 21 st Street the dune remained stable and gained a veneer of sand but at 23 rd Street a 2-3 foot high scarp was cut and by 26 th Street the scarp increased to 6-7 feet as the seaward slope was cut landward to the crest. This erosion returned the beach to essentially its pre-sandy configuration. Engineered Beach History: Included here is a brief description of the engineered beach timeline of events since construction in the fall of The initial beach nourishment project several years in development was co-sponsored by the City and the New Jersey Department of Environmental Protection (NJDEP) started in fall 2009 and was just short of the completion of construction when it was interrupted by the November 2009 northeast storm. The dredging company, Great Lakes Dredge and Dock, Inc. (GLDD), was forced off the beach by the storm (the third in a nine-storm series) on November 11, 2009 with under 70,000 cubic yards of sand left to pump. That storm produced a US Presidential disaster declaration (DSR-NJ 1867) on December 22, This allowed the Federal Emergency Management Agency (FEMA) to review the losses to the community including the new beach (covered under Category G loss to parks and recreation facilities). Since the project was funded initially by a cooperative agreement with the NJDEP (75% of cost) and the City (25% of cost), the project qualified for 75% of the cost to replace the sand lost to the storm as a recovery, when and if the City determined to restore the project. GLDD completed the initial 2009 fill project during the fall of 2009; placing 1,400,000 cubic yards (cy) of sand between a point 600 feet west along the Hereford Inlet shoreline eastward to 2 nd Avenue groin and south 600 feet into the City of Wildwood. That winter had a particularly active storm season and as a result, the northeast beaches suffered substantial erosion as sand from the inlet area was moved to the area south of 6 th Avenue. Another northeast storm in March 2010 removed an additional volume of sand impacting the southern end of the City (DR-NJ 1897). In the spring of 2010, the City of North Wildwood entered into a restoration maintenance contract with GLDD to pump sand from the same borrow area and place some sand from 2 nd Avenue south to 6 th Avenue (the shoreline adjacent to Hereford Inlet and most affected by the storms). This work was partially funded by FEMA disaster relief money as a result of the two declared northeast storm events. Pumping resumed at 11 th Avenue and continued south to the City of Wildwood boundary. Data collected by GLDD showed that the northern section of the beach received 58,000 cy of sand while the area to the south received 406,000 cy for a total of 464,000 cubic yards. This work was completed by July 10, The El Nino phenomenon that dominated the winters strong northeast storm season abated and in the winter of there were fewer northeasters or significant storms. One of the more memorable 2

5 storms that affected the Cape May County shoreline during the winter of was the Christmas Blizzard (Dec. 26 th ) which brought high winds and water levels and caused some beach erosion in parts of the county. Hurricane Irene made landfall in New Jersey on August 29, 2011the engineered beach lost 82,252 cubic yards of sand. In response to losses from Irene the city once again made a commitment to restore eroded sand from the engineered beach. The City under FEMA DR-NJ 4021 incorporated a claim for Category G reimbursement. During the spring of 2012 the city proceeded with a sand back pass program to haul up to 96,000 cubic yards of sand from Wildwood Crest to the northern erosional zone between 2nd and 7th Avenues. Hurricane Sandy made landfall near Atlantic City on October 29, 2012 in North Wildwood the beach lost 153,000 cubic yards of sand. Norfolk Dredging commenced beach nourishment work on June 12, 2013 and by July 2, 2013 had placed 150,530 cubic yards of sand in North Wildwood. The project restored the beach to approximately 83% of the initial fill template volume. As such the project would again be eligible for FEMA reimbursement under Category G losses to an engineered beach project. Oceanfront Beach Surveys: The CRC surveyed shoreline changes at all 54 oceanfront profile stations three times in 2013 to depict annual and seasonal trends as well as document changes from the 2013 beach nourishment project. These surveying activities continue a monitoring program that began in 2009 following the initial City/State beach restoration project. The profile stations are spaced 200-feet apart and were established to determine cumulative changes and performance of the beach restoration project. Figure 1 shows the locations of a few selected profile survey locations that were extracted from the 54 profile dataset: Lines 04+00; 20+00; 40+00; 52+00; 58+00; and These sites were chosen to depict the general elements of the project. The two northern sites document changes in the erosional zone, the middle two sites show that sand has been deposited in the midsection, and the southern two sites cross the eroding dune system that surrounds the ends of the four piers south of 21 st Avenue. A discussion of the changes at each of these locations is provided in a later section of this report. The following is a list of the studies included in this report and the dates of the surveys: Survey 14 October 16, 2012 Survey 16 May 22, 2013 Pre-fill Survey 17 July 10, 2013 Post-fill Survey 18 November 13, Figure 1. Shown above are locations of six representative profile sites of the 54 profile stations where shoreline changes were measured on the City s oceanfront from October 2012 to November For each of the six profile stations descriptions and cross sections are provided to show typical changes over the year 3

6 Figure 2. A digital elevation model for the North Wildwood City shoreline showing the original project extent. This elevation difference map of the North Wildwood City engineered beaches shows the change in elevations between May 2013 pre-fill and July, 2013 post-fill surveys. The dark green areas were those where the project placed sand in the regions of primary chronic erosion. The reddish band that sweeps from end to end was offshore losses not related to the project. A breakdown by regions of sand volume gains vs losses is include in the volume change table on the map overall the project placed 150,530 cubic yards of sand on the beaches in front of the piers and between the 2 nd Avenue jetty and 6 th Avenue. 4

7 Figure 3. A digital elevation model for the North Wildwood City shoreline showing the conditions of the engineered beach 5 months following the 2013 project. Overall the beach still showed a gain of 203,900 cubic yards of sand. Regions of sand placement still showed modest gains (green) while the offshore lost sand (red). 5

8 Figure 3. This map shows the elevation difference for the year to just prior to Hurricane Sandy October 2012 to November2013. This timeframe includes losses due to Hurricane Sandy and winter storm Saturn plus any sand volume gained from the 2013 beachfill project. The overall volume change was a loss of 275,000 cubic yards of sand. Regions of red show the areas of the greatest losses while greens are regions of elevation gains. The vast majority of the net loss was from the nearshore and offshore seafloor; pockets of losses inshore were focused near the piers and between 2 nd and 5 th Avenue. Onshore between 6 th and 22 nd Avenues the beach was extremely stable. 6

9 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 City s beaches for Beach volume and shoreline changes were calculated from October 2012 (pre-sandy) to November Site (between 3 rd and 4 th Avenues) The site is located in the northern portion of the island adjacent to Hereford Inlet 400 feet south of the 2 nd Avenue jetty. This area has typically been an erosional shoreline due to the proximity to the inlet and the impact from northeast storms. In 2012 sand was hauled by truck to reinforce the beach and add to the dune in an attempt to balance recreational needs with the inevitability that the site is erosional until nature restores inlet tidal dynamics to pre-1998 conditions along this part of the shoreline. Following Hurricane Irene, a back-passing project added 93,000 cubic yards of sand most deposited between the jetty and 7 th Avenue derived from excess beach sand found on the beaches of Wildwood Crest 3 miles south. The beaches rapidly eroded following sand placement when Hurricane Sandy followed by winter storm Saturn flattened the remaining beach and dune to the street end revetment. During the 2013 restoration project to repair erosion caused by Sandy Norfolk Dredging Company placed 83,022 cubic yards of sand in this region from the 2 nd Avenue jetty to approximately 6 th Avenue. The dune was restored but with a lower crest elevation than present on October 10, 2012 with a restored dry beach berm that extended 350 feet seaward from the base of the revetment. Restored beach berm elevation was at 7 feet NAVD88 with a dune crest elevation of 15 feet NAVD88 the width of the dune was approximately 130 feet at the toe. Erosion occurred rapidly with a 3-foot high scarp cut into the beach berm on July 2, 2013 just as the project was completed. By November 11, 2013 just five months following construction the inlet tidal currents and wave climate combined to erode the project berm and the seaward slope of the dune. The site lost yds 3 /ft. of sand from the beach and dune with nearly 134 feet of shoreline retreat. The beach berm elevation decreased from 7 feet NAVD88 to barely 4 feet NAVD88 at the dune toe that resulted in a 2 foot high dune scarp in the seaward slope. For the year the site was 2.41 yds 3 /ft. of sand ahead of its pre-sandy conditions, all of the volume gain was below the zero datum on the nearshore slope. The shoreline position (zero datum) advanced 21 feet but this was the result of a flatter beach slope rather than additional sand on the beach. Onshore the November 2013 beach configuration mimicked the October 2012 conditions except the dune system was lower in elevation (4 feet) and slightly landward.. 7

10 Figure 4. View taken from 3 rd Avenue looking south along the dune toe on March 7, 2013 following Winter Storm Saturn. The beach was flattened by the storm waves and surge. Storm waves cut into the seaward dune slope leaving a 3-5 foot high scarp along the dune crest. Buried dune fence was exposed and damaged by the storm waves. Figure 5. View from 2 nd Avenue seawall looking south taken on May 10, 2013 prior to commencement of the 2013 maintenance project. The beach remains narrow and flattened with the dune scarp cut during Saturn still present in the distance south of the 3 rd Street outfall pipe. At low tide the beach is still accessible to beach patrons and recreational fishermen. 8

11 Figure 6. View from 2nd Avenue seawall again looking south taken on June 18, 2013 as the 2013 USACE maintenance project was underway. The submerged dredge pipeline came ashore just north of the 3 rd Street outfall pipe seen in the photo above. Sand placement had raised the elevation of the beach and created a dry beach berm that extended approximately feet seaward of the revetment and dune toe. The pipeline was extended south to complete repairs seaward of the piers followed by additional sand placement and dune restoration in this region. The project was completed in early July. Figure 7. View from 4th Avenue looking north taken on November 12, 2013 approximately 5 months following the 2013 maintenance project. The dune had been restored during the summer project with new fence installed on the seaward slope to capture aeolian sand and prevent foot traffic. The beach berm elevation has been lowered and the width landward nearly 200 feet following the project but the beach width prevented major dune erosion and allowed continued vehicle access to the beach at 2 nd Avenue. 9

12 Figure 8. The combined effects of Hurricane Sandy and winter storm Saturn flattened, lowered and pushed the already narrow and low elevation beach 90 feet further landward. The dune system was fully breached and the 100 foot wide tall dune with a crest elevation of 20 feet NAVD88 was essentially obliterated. The 2013 maintenance beach nourishment project restored the dune to a similar width with a crest elevation of 16 feet NAVD88. A beach berm at elevation 7 feet NAVD88 extended seaward over 200 feet from the seaward dune toe. Unfortunately the fall wave climate and Hereford inlet tidal currents combined to erode the beach berm landward to the dune toe removing nearly 200 0feet of recreational beach in 5 months. The net profile volume change for the year was a modest gain of 2.41 yds 3 /ft. of sand with a similar modest shoreline position advance of 21 feet. 10

13 Site (between 9 th and 10 th Avenues) This site is located approximately 2,000 feet south of the inlet and has represented a transition zone (from erosion to deposition) in previous years. Hurricane Sandy has temporarily reversed this trend as the storms waves and surge severely eroded the beachface and recreational beach berm that reduced the overall dry beach width by 160 feet. The dune was unaffected by the storm due to the 400-foot wide beach attenuating the breaking waves and absorbing the energy before they reached the dunes. Despite the severe erosion this beach remained over 250 feet wide and supports recreational activities and continued to provide sufficient storm protection for the dune and oceanfront properties and infrastructure. The beach is still within the design template configuration parameters. As a result no sand was placed in this region during the 2013 maintenance project. Aeolian sand continued to accumulate on the seaward dune slope and toe as the wide beach provided a source of sand. Sand continued to accumulate on the dune through November Natural recovery temporarily partially restored 80 feet of the beach berm width by the end of June 2013 with spring/summer beach building processes moving sand landward under favorable wave and weather climates. By November this accumulation of sand onshore was again flattened by the fall wave climate returning the beach width to the post Sandy conditions. By the fall survey the shoreline position had retreated 34 feet and the site lost yds 3 /ft. of sand mostly from the beachface and the nearshore seafloor. As a result erosion caused by Sandy still dominated the annual changes in the comparison between the October 12, 2012 and November 11, 2013 surveys. This comparison showed the shoreline position retreated 43 feet landward with a net sand volume loss of yds 3 /ft. of sand below the pre-sandy conditions. The berm width retreated landward 160 feet with the beachface slope flattened by Sandy s storm waves and fall 2013 wave climate. 11

14 Figure 9. View to the north taken from the berm at 10 th Avenue on May 10, Sandy and Saturn combined eroded 160 feet of beach width here. The beach width and elevation has remained relatively stable, aeolian sand accumulated along the upper beach and dune toe. The recreational berm width still extended about 250 feet seaward of the dune toe at elevation 6 NAVD 88 as of May 10, Figure 10. View to the north taken from the berm at 12th Avenue on November 11, The beach width and elevation returned to its post-sandy configuration during the second half of No sand was placed here directly during the summer beach maintenance project but the site has benefited from cross-shore and longshore sediment transport over time. The wide dry recreational beach berm provides substantial storm protection for the dune system and acts as a massive source of aeolian sand to feed into the dune system where sand has accumulated on the lower third of the seaward dune slope and toe. 12

15 Figure 11. Hurricane Sandy combined with winter storm Saturn eroded nearly 160 feet of the massive beach berm that existed on October 12, Despite this extensive erosion over 250 feet of beach berm width remained intact at elevation 6 NAVD88. The wide beach provided ample storm protection to prevent dune erosion. During 2013 this section of dune accumulated sand along the seaward toe and slope. No sand was placed directly on this beach during the 2013 beach maintenance project but cross-shore and longshore transport did move sand to this beach through natural processes in the summer and partially restored the berm width lost during the recent storm events. The fall wave climate flattened this summer berm as sand moved cross-shore once again to the offshore slope, deposition likely continued beyond the survey limits. The severe onshore and nearshore losses suffered during Sandy offset any gains offshore for a net loss of yds 3 /ft. of sand for the year. 13

16 Site (17 th Ave.) Positioned 4,000 feet south of the 2 nd Avenue jetty, this site is located two blocks south of the lifeguard station in the mid-section of the City s oceanfront beaches. Following initial construction this region has remained relatively stable. The wide beach has protected the dune ridge, constructed during the initial project phase, from erosion through multiple storm events including Hurricanes Irene and Sandy. Waves and storm surge from Sandy and winter storm Saturn combined flattened the beachface slope and reduced the recreational beach berm width nearly 180 feet. Although the beach was severely eroded it absorbed the wave energy and effectively provided wave attenuation protecting the dune system, oceanfront properties and public infrastructure for wave damage during Sandy. Prior to Sandy the beach width extended seaward of the dune system approximately 575 feet. With nearly two thirds of the massive beach width or nearly 400 feet of dry beach still intact seaward of the dune following Sandy there was no need to place sand in this region during the 2013 maintenance project. This site continued to suffer modest erosion in the second half of 2013, the shoreline position retreated 42 feet with a loss of yds 3 /ft. of sand mostly stripped from the beachface slope during the fall of For the year this site has lost 76.5 yds 3 /ft. of sand compared to before Sandy with a shoreline position retreat of 140 feet. Natural recovery in this region was limited in 2013 how sand is redistributed following the project will be seen by how this site recovers in If the majority of sand shed from the project is carried south into Wildwood this site may continue to erode through 2014 in the absence of cross-shore sediment transport from any sand possibly deposited during recent storms far offshore beyond the survey limits. Figure 12. View to the north from the beach located near 17 th Avenue on May 9, The recreational beach berm width is massive extending seaward nearly 350 feet from the dune toe at between elevations 6-7 feet NAVD88. No sand was placed here during the 2013 beachfill project as the beach remained above the design template following Sandy and Saturn. The dune continued to accumulate aeolian sand transported across the wide beach towards the dune system. 14

17 Figure 13. Prior to Sandy this recreational beach berm extended seaward of the dune nearly 600 feet. Sandy and Saturn combined to erode nearly 200 feet from the berm width. By May 2013 the recreational beach berm width was still massive extending seaward 350 feet from the dune toe at between elevations 6-7 feet NAVD88. No sand was placed here during the 2013 beachfill project as the beach remained above the design template. The dune continued to accumulate aeolian sand transported across the wide beach towards the dune system. By November 8, 2013 the site had lost yds 3 /ft. of sand and the shoreline position retreated 140 feet compared to pre-sandy conditions. 15

18 Site (21 st Ave.) At this location, the engineered dune begins its seaward jog in its alignment from just seaward of the boardwalk to run seaward of the eastern ends of the southern piers. Located near the beginning of the jog several hundred feet of dry beach still protected the dune system at this location and to the north, to the south the beach width seaward of the dune diminished significantly by the project design. During Sandy the beach width was reduced by 75 feet with sand distributed toward the dunes and offshore. Prior to Sandy the beach berm was nearly 400 feet wide by May 2013 this was reduced to about 325 feet seaward of the dune toe. Located just north of the northern fill taper of the pier section for the 2013 project this site did not receive sand directly but likely benefited from sand runoff from the project area. By the end of June 2013 the beachface accumulated sand that expanded the beach berm width nearly 40 feet. Sand also filled in the nearshore scour trough cut by Sandy and Saturn over the summer and fall as sand moved longshore and cross-shore towards this beach. During the second half of 2013 the site gained a net yds 3 /ft. of sand added both onshore and nearshore. The annual changes from October 11, 2012 to November 8, 2013 were still dominated by erosion caused by Sandy. For the year the net volume change was a loss of yds 3 /ft. of sand with a modest shoreline position retreat of 13 feet. Aeolian sand was added to the seaward dune slope and to the crest but the recreational berm width remained 60 feet landward of the pre-sandy configuration. Although some sand moved cross-shore towards the beach filling the Sandy related scour trough the nearshore bar present prior to Sandy has not yet reformed. Figure 14. View to the north from the beach located near 22nd Avenue on May 8, The recreational beach berm width remains nearly 300 feet seaward of the dune toe. The dune position in this region begins a seaward jog in the alignment to run seaward of the southern piers. This location did not receive any sand directly during the 2013 beachfill. 16

19 Figure 15. Following Hurricane Sandy and winter storm Saturn the beach berm was flattened and retreated landward nearly 100 feet. A deeper trough was scoured by the storm wave s nearshore and sand transferred offshore to beyond the survey limits. Located near the southern taper of the northern deposition zone for the 2013 beachfill project no sand was placed here directly. In the months following sand accumulated onshore partially restoring the berm width and elevation. A thin veneer of sand was added to the upper beach dune toe and seaward slope and crest. Offshore sand moved landward partially filling the nearshore trough. The net change for the year compared to before Sandy to November 2013 was a modest loss of 10.74yds 3 /ft. of sand. 17

20 Site (between 23 rd and 24 th Aves.) This site is located in the southern section of the City s oceanfront where the engineered dune system lies seaward of the piers. The seaward jog in the dune system has made them vulnerable to the spate of frequent storms since With limited beach width seaward of the feature to attenuate wave action and absorb the energy before impacting the seaward slope the feature has suffered severe erosion. During Sandy the proximity of the dunes to the shoreline, made them no match for this event. Dunes were entirely washed away south of 22 nd Avenue and the beachface and berm flattened by the storm waves and surge. As a result of this damage the city imitated a beach maintenance project in 2013 to restore the engineered beach seaward of the piers. Norfolk dredging placed 67,508 cubic yards of sand in this region to rebuild the dune and beach to approximate design template. The dune was reconstructed to a crest elevation of 12 feet NAVD88 and approximately 100 feet wide at the toe. A recreational berm was built that extended over 100 feet seaward of the dune toe at elevation 7 NAVD88. Again rapid erosion followed the project and by the end of June 2013 a 2.5 foot high beach scarp was cut into the berm as the beachface retreated under the wave climate. Through fall 2014 erosion continued to cut away the beach berm and by November 11, 2013 the waves were impacting the seaward dune slope at higher tides that cut a 3 foot high scarp in the seaward dune slope. The berm retreated 140 feet and the elevation lowered 4 feet cutting away the seaward dune toe. Sand was also scoured from the nearshore slope by the fall wave climate that increased the depth by up to 5 feet. There was little evidence in the survey data to indicate sand was transferred offshore in large quantities. It is more likely that predominate currents and waves swept the sand south. As a result of these losses the second half survey showed a retreat in the shoreline position of 113 feet with the net loss of yds 3 /ft. of sand split fairly evenly between the onshore and nearshore regions of the profile. For the year the net loss was more modest as the project partially offset the Sandy storm losses. From October 10, 2012 to November 11, 2013 the site loss 13.61yds 3 /ft. of sand while the shoreline position was relatively stable retreating less than 8 feet. By November 2013 what remained of the beach was flattened and lowered to less than 3 feet NAVD 88 which allows any waves to reach the dune toe at higher tides. This dune/beach configuration provides minimal wave attenuation, increases the risk of dune breaches during storms and increases the maintenance cost of attempting to maintain a dune feature in its present position and alignment. 18

21 Figure 16. View to the north taken on May 6, 2013 from near 24 th Avenue showing the pier end and terminal end of the remaining dune where it jogs east. Hurricane Sandy and winter storm Saturn have flattened the beach berm and eliminated the dune ridge. Following the storms wave run up reached the pier pilings at high tide prior to the startup of the 2013 beachfill project. Figure 17. View to the north taken on June 26, 2013 from near 23 rd Avenue showing the 2013 beachfill in progress. Discharge pipeline is still on the beach while summer beach patrons enjoy the recently restored beach. A dune ridge was re-established with a row of dune fence installed along the seaward toe to limit cross-over and collect aeolian sand. No grass was planted in contrast to the pre-existing dune feature delineated by where the grass line begins. 19

22 Figure 18. Hurricane Sandy and winter storm Saturn combined to flatten the beach berm and eliminate the dune, the nearshore was scoured and sand transferred cross-shore well offshore to near and beyond the survey limits where a shore parallel bar developed. By the end of June the 2013 beachfill had restored the dune ridge and beach berm that extended approximately 100 feet seaward of the dune toe at elevation 7 NAVD88. The project beach and sand placed nearshore immediately began to erode as the fall wave climate driven by 72 hours of 30 knots plus onshore winds in October 2013 removed nearly the entire project beach berm by November Despite the beachfill the site still suffered a net loss of yds 3 /ft. of sand for the year. 20

23 Site (between 25 th and 26 th Avenues) This is the southern-most cross section of the selected profiles within the larger database. Located seaward of the Surfside Pier and Ocean Oasis Water Park and Beach Club this site represents conditions at the south end engineered beach and taper near the Wildwood and North Wildwood border. Initially the engineered beach design template placed the dune feature 30 feet seaward of the pier s steel bulkhead. A series of storm events that followed construction in 2009 has resulted in multiply episodes of erosion followed by restoration efforts to maintain this section of dune. The beach seaward of the feature is narrow and prone to storm erosion. Hurricane Sandy struck the New Jersey shoreline following completion of restoration efforts to replace losses suffered during Hurricane Irene. A narrow lower elevation dune ridge was rebuilt with a modest beach berm to help protect the pier steel bulkhead from wave impact. Sandy s waves and storm surge flattened the beach and dune but the steel bulkhead held and protected the pier and water park from direct wave impact once the sand eroded under the fury of the storm. Again the 2013 maintenance restoration project placed 67,508 cubic yards of sand on the beach in this region. The restored dune was nearly 100 feet wide at the toe with a crest elevation of 12 NAVD 88. The beach berm extended seaward of the dune toe 100 feet at elevation 6 NAVD 88 that pushed the shoreline position seaward 125 feet with sand added to the nearshore slope. Unfortunately the fall ocean wave climate quickly eroded the new project beach. The berm was nearly completely removed and flattened that allowed wave propagation and higher tides to impact the seaward dune slope. By November nearly half the dune was eroded leaving a 7-8 foot high scarp along the seaward dune crest. The beach berm elevation was reduced from 6-7 feet NAVD 88 to 2-4 feet NAVD 88 that continued to allow higher tides to reach the seaward dune slope. A modest volume of sand was transferred cross-shore but longshore drift swept most of the eroded sand south. From June 2013 to November 2013 the site lost yds 3 /ft. of sand with 83 feet of shoreline position retreat. Although losses from the project beach were immense the site is nearly even when compared to pre-sandy conditions. The net annual change was a loss of just1.36 yds 3 /ft. of sand and a shoreline position advance of 6 feet. 21

24 Figure 19. View from near 25 th Avenue looking to the north along the steel bulkhead on May 6, 2013 prior to the 2013 beachfill project from approximately where the dune crest at profile line location existed pre-sandy. The beach was flattened and dune system eliminated by Sandy and further eroded during winter storm Saturn. Higher tides reach the steel bulkhead and the beach is essentially as narrow as it was prior to the 2009 project. Figure 20. View from near 25 th Avenue looking to the north along the newly established fenceline on June 27, 2013 just following completion of the 2013 beachfill project from approximately where the dune crest at profile line location existed. The engineered beach width and elevation was re-established during the project along with a modest dune ridge. During the fall 2013 the wave climate again eroded the beach and dune. Repetitive dune erosion prompted the City to consider other options. 22

25 Figure 21. Hurricane Sandy and winter storm Saturn combined to flatten the beach berm and eliminate the dune, the nearshore was scoured and sand transferred cross-shore well offshore to near and beyond the survey limits where a shore parallel bar developed. By the end of June the 2013 beachfill had restored the dune ridge and beach berm that extended approximately 100 feet seaward of the dune toe at elevation 7 NAVD88. The project beach and sand placed nearshore immediately began to erode as the fall wave climate driven by 72 hours of 30 knots plus onshore winds in October 2013 removed nearly the entire project beach berm by November Despite sand placement during the beachfill the site still suffered a modest net loss of 1.36 yds 3 /ft. of sand for the year. 23

26 Summary The 2009 beach restoration project was constructed to create an engineered beach, provide dune and shore stability and enhance storm protection for the City s eroding oceanfront shoreline. Regular monitoring has identified two erosional hotspots and a wide zone of accumulation. The shoreline near the piers in the southern reach as well as the shoreline adjacent to Hereford Inlet is subject to erosion due to the proximity of the tidal inlet and the alignment and configuration of the dune and beach seaward of the piers. While both of these sections have been erosional the beaches located in central section of the engineered beach have accumulated sand since the initial construction, as the sand eroded from the northern project beaches is swept south. Sand from the erosional zone seaward of the pier is predominantly transported by storm waves south into the City of Wildwood although temporary seasonal reversals in sand transport occur. In 2011, this trend continued and it was enhanced by the passage of Hurricane Irene in late August. Shoreline retreat was evident on the northern half of engineered beach representing a 2 4 ft loss in elevation over the previous year and extended from the northwest corner of the study area curving along the shoreline to the ocean facing beaches continuing south in a declining fashion for about 2,000 feet. Some of the sand lost from the shoreline was moved by longshore currents to the south. The dunes and beaches in front of the piers also continued the erosional trend while the central region of the City s beaches (6 th Avenue to 20 th Avenue) was a location of deposition. The City initiated a sand backpassing program in 2012 with Wildwood Crest to move excess sand from Wildwood Crest to the erosional beaches in North Wildwood. In late October 2012 Hurricane Sandy devastated much of the New Jersey coast. By comparison the North Wildwood shoreline fared well. The two erosional zones suffered severe beach and dune erosion but the wider beaches in the central section absorbed and attenuated the wave energy as a result the dunes in this region remained intact. At the inlet the storm waves and surge overwashed the narrow beaches and flattened the dune system. Seaward of the piers the seaward alignment of the dune system again exposed it to the storm waves and surge. The beach and dune system was flattened and the storm surge flowed into the City streets through access openings beneath the boardwalk. Winter storm Saturn waves and surge impacted the coast on March 5-6, 2013 furthered flattened the beach berm and slowed natural recovery from Sandy. The storm eroded 278,083 cubic yards of sand, but the mid-section gained 128,457 cubic yards for a NET loss of 149,626 cubic yards of sand. Distribution of sand prior to Sandy meant that some areas of the beach had sand in amounts above the design cross sections; these had to be subtracted when applying for storm damage aid to arrive at a 143,880 cubic yards sand volume applicable for FEMA reimbursement. Norfolk Dredging commenced beach nourishment efforts on June 12, 2013 and by July 2, 2013 had placed 150,530 cubic yards in North Wildwood to restore the erosion caused by Sandy. The project placed 83,022 cubic yards of sand on the beach between the 2 nd Avenue jetty and 6 th Avenue and 67,508 cubic yards between 22 nd Avenue and 26 th Street and restored the dune and beach width. Following completion of the project the fall wave climate driven by 72 hours of persistent 30 knot plus onshore winds generated around October 10, 2013 cut into the project beach and caused extensive beach erosion in the erosional hotspot regions recently restored. Comparing the engineered beach study area between May 2013 and November 2013 the net change was a gain of 203,900 cubic yards of sand mostly derived from the project. However, the annual volume change from October 12, 2012 prior to Sandy s arrival to November 12, 2013 showed a net loss of 275,000 cubic yards of sand. In addition to losses near the piers following the project and Sandy the offshore bar was flattened and nearshore scoured over the entire project region from the combination of Sandy and Saturn. This loss of sand offshore and nearshore will likely delay natural sand recovery until favorable conditions develop to move sand from further offshore in deeper water toward the shoreline. This normally occurs with large long period swells created by offshore tropical systems. 24

27 The engineered beach has performed as designed the beaches and dune system have absorbed and attenuated wave propagation and protected the community during two hurricanes and several northeast storms that all resulted in storm disaster declarations following initial construction in Wider beaches provide ample recreational space for summer beach patrons while enhancing storm preparedness and community resilience. Although the mid-section of the City s oceanfront shoreline has remained relatively stable the north and south ends continue to suffer erosion and require frequent re-nourishment to maintain the design dune and beach template. At the north end inlet dynamics, orientation to the northeast and tidal flow exposes this region to near continuous erosional processes associated with its proximity to Hereford Inlet. In contrast the south end erosional concerns stem from the original engineered beach design concept to include the seaward pier ends within the sheltered protection of the dune system. To do so required a 250-foot seaward offset in the dune alignment. This re-alignment reduced the beach berm width seaward of the dune by 200 feet to accommodate the dune and still allow an access road seaward of the piers. The reduced beach width proved insufficient to absorb and attenuate the recent wave climate with the increased frequency of severe storm events. Once the beach erodes the dune system is exposed to direct wave assault and full breaches. As a result the City has followed recent recommendations to restore the dune alignment in compliance with the U.S. Army Corps of Engineers (USACE) design template in the proposed federal project for the Wildwoods. This design shifts the dune landward about 250 feet under the piers that effectively increases the beach width seaward of the dune feature by the same amount. The additional beach width will protect the dune from frequent wave run up, reduce erosion and help enhance storm preparedness for the community. In addition intervals between required beach and dune maintenance should be extended thereby reducing the expense associated with frequent re-nourishment efforts in this region. 25