FINAL REPORT FOR 2013 ON THE CONDITION OF THE MUNICIPAL OCEANFRONT BEACHES THE BOROUGH OF AVALON, CAPE MAY COUNTY, NEW JERSEY

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1 FINAL REPORT FOR 2013 ON THE CONDITION OF THE MUNICIPAL OCEANFRONT BEACHES THE BOROUGH OF AVALON, CAPE MAY COUNTY, NEW JERSEY View from 12 th Street to the south taken February 28, 2013, following completion of the USACE 2013 maintenance project in early February, winter storms including Saturn quickly eroded the project beach. Pronounced scarping along the berm ridge (above) was seen prior to the arrival of Saturn, symptomatic of the chronic erosional trend along the northern Avalon shoreline. Shortly following this photo Saturn struck, the project berm eroded landward another 60 feet during the storm leaving a narrow strip of dry beach seaward of the dune toe. PREPARED FOR: THE BOROUGH OF AVALON 3100 DUNE DRIVE AVALON, NJ PREPARED BY: THE RICHARD STOCKTON COASTAL RESEARCH CENTER 30 WILSON AVENUE PORT REPUBLIC, NEW JERSEY JANUARY 2014

2 Table of Contents Introduction 1 Impact from Winter Storm Saturn 1 Monitoring Program 1 Oceanfront Beach Surveys 2 Table 1: 2013 Oceanfront Beach Profile Quarterly Volume Changes 3 Table 2: 2013 Oceanfront Beach Profile Annual Volume Changes, Pre-Sandy 4 Individual Oceanfront Site Reviews-- 9 th to 78 th Streets 5 Photographs 1a, b, c to 10a, b, c for Each of 10 Oceanfront Profile Sites 6-42 Figures 1 to 19 Quarterly Cross Sections - 10 Oceanfront Profile Sites 7-43 Figures 2 to 20 Annual Cross Sections 10 Oceanfront Profile Sites 8-44 Summary of Avalon s Oceanfront Beaches 45 Engineered Beach Six Month Review 45 Digital Elevation Model 46 Figure 21 After Dredge DEM 47 Figure 22 Six Month Post Fill DEM 48 Six Month Volume Change 49 Figure 23 Six Month Elevation Change Map 50 Figure 24 Transect Reference Map 51 Figures Engineered Beach Cross Sections Engineered Beach Six Month Summary 54 Recommendations 55 i

3 ANNUAL REPORT FOR TO THE BOROUGH OF AVALON ON THE CONDITION OF THE MUNICIPAL BEACHES Introduction: The Richard Stockton College of New Jersey Coastal Research Center (CRC) was tasked with a review of the municipal oceanfront shoreline within the Borough of Avalon over the past year. This annual report presents a discussion of the changes to the beach sand volume, shoreline positions, and the impact of winter storm Saturn plus follows the performance of the 2013 US Army Corps of Engineers (USACE) maintenance project along the north end engineered beach. During the winter the US Army Corps of Engineers (USACE) completed an emergency maintenance project on the northern beaches based on erosion suffered during Hurricane Irene and Sandy placing a reported 336,359 cubic yards (CY) of sand on the engineered beach. The project was eligible for Flood Control and Coastal Emergency funds under Public Law and in response to P.L Disaster Relief Appropriations Act the project beach was eligible for restoration to design template. When the project was completed the beach width and elevation had been restored to pre-storm conditions. CRC surveys at the five monitoring sites within the engineered beach area showed a net gain of 277,260 CY from November 30, 2012 to March 1, 2013 following construction. Shoreline positions from the jetty to 28 th Street advanced seaward approximately feet during the project. Unfortunately, winter storm Saturn impacted the Jersey coast soon after the USACE project was completed. 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 the Avalon 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 stripped sand from the recently completed project beaches, 94,942 CY of sand was lost from the project region, when limiting loss volumes to onshore part of the profile, the volume increased to 112,321 CY or approximately 33% of the 336,359 CY of sand placed on the beach. Saturn s storm waves also caused substantial erosion along the southern shoreline, flattened the beach elevation and reduced the beach width. The recently constructed project berm, although severely eroded during the storm, did absorb the storm surge and wave energy that prevented damages to the dune system. Similarly the south end beaches had partially recovered naturally following Sandy with substantial beach width and elevation gained all of which diminished the storm waves before they impacted the dune system. Total net volume change for the Avalon shoreline from Saturn was a loss of 350,832 CY, significant when compared to Sandy s 440,000 CY. The impact of both storms combined stripped 790,832 CY of sand from the Borough s oceanfront shoreline within a 4-month period. Recovery following Sandy did mean that a considerable percentage of that total was sand re-eroded from the berm after being transported offshore at the end of October in Sandy and returning by early March 2013 to face the impact of Saturn. Monitoring Program: The CRC monitored the ten oceanfront cross sections five times in 2013 including an emergency survey following winter storm Saturn. These surveying activities continue a monitoring program dating back to 1

4 1981. Monitoring provides details on sediment movement along the Borough s Atlantic shoreline and surveying has continued through multiple beach restoration projects starting in 1987 with a local/state sponsored project. The USACE restored the ocean beaches starting in 2002, with the Borough and State providing additional sand hydraulically pumped onto the beach in 2006 and Trucks were used under contract to haul in quarry sand in 2007 and 2009 to restore recreational access between 10 th and 17 th Streets. Trucks were utilized again in 2010 to restore the dune in the 4-block section between 17 th and 21 st Streets followed by the 643,000 CY sand pumping in June of In 2011, a federal maintenance beach replenishment project placed 450,000 CY of sand on northern beaches. A back-passing program was implemented as a pilot project in 2006 to recycle 58,000 CY of sand hauled to the northern shoreline from surplus material obtained between 31 st and 70 th Streets. This was repeated again in 2012 under US Army Corps authorization when 63,956 cubic yards of sand were hauled from the same source beaches to the zone between 12 th and 21 st Streets. Following Hurricane Sandy the USACE conducted an emergency maintenance project in early 2013 to restore the engineered beach design template with placement of 336,359 CY of sand. The following is a list of quarterly studies included in this report and the dates of the surveys: Survey 120 November 30 & December Survey 121 February 28 & March 1, 2013 Survey 122 EM Post-Saturn March 7, 2013 Survey 123 May 30 & 31, 2013 Survey 124 September 16 & 17, 2013 Survey 125 December 11 & 12, 2013 Oceanfront Beach Surveys: Oceanfront beaches were surveyed quarterly to depict both seasonal and annual changes. The observations show trends in both shoreline position and volume that occurred in Table 1 shows trends in sand volume by quarter, table 2 the annual change to pre-sandy. The USACE project dominated the first quarter restored the north end beach and dune system to design template that offset some modest volume losses on the southern shoreline for a net gain of 209,224 CY of sand between fall 2012 and winter 2013 along the Borough s oceanfront shoreline. Winter storm Saturn quickly followed the project s completion on March 5, 2013 and caused significant beach and nearshore erosion. The Borough s oceanfront shoreline lost 350,832 CY of sand as the beach absorbed the wave energy but the dune system remained unscathed that protected public infrastructure and oceanfront properties from storm wave damage. Weather patterns in the spring quarter transitioned from storms to calmer wind and wave conditions favorable for natural sand recovery. By May the Borough had recovered nearly half the Saturn losses, 163,058 CY of sand. Initial recovery was focused on the southern shoreline as predominant longshore currents transferred sand south. Northern sites continued to erode focused on the seafloor through spring until the predominant summer wave and wind patterns from the south reestablished a temporary northerly drift shifting sand back onshore along the north end engineered beaches. This natural recovery added 250,162 CY of sand to the shoreline during the summer, the gentle summer wave climate was favorable for natural beach building to reestablish a wider, higher recreational beach berm for the summer season. The north end gains were again quickly lost with the onset of 72 hrs of 30 plus knot onshore winds on October 10 th. Waves generated during this event eroded the beach, flattened the berm and scoured the nearshore. This was the initial event in a series of storms to impact the Jersey shoreline during the winter storm season By December the Borough s shoreline had lost another 309,215 CY of sand focused on the north end that eliminated the onshore summer recovery within the project area. Table one below summarizes the sand volume changes at each site during

5 Table Oceanfront Beach Profile Quarterly Sand Volume Changes Profile Winter Saturn Spring Summer Fall Number 11/12-3/13 3/1/13 3/7/13 3/13-5/13 5/13-9/13 9/13-12/13 8th Street Jetty (yds 3 /ft) (yds3/ft) (yds 3 /ft) (yds 3 /ft) (yds 3 /ft) AV AV AV AV AV AV AV AV AV AV Quarterly Volume Change (yds 3 ) = 209, , , , ,215 The net change during 2013 was a loss of 37,603 CY despite the efforts by the USACE and persistent natural processes that produced robust sand recovery and beach building during the spring and summer seasons. Winter storm Saturn followed by several early fall storm events produced strong onshore winds and waves that eroded sand placed onshore, scoured nearshore gains and transferred sand offshore to the profile limits or swept south on longshore currents. 3

6 Table Oceanfront Beach Profile Annual Sand Volume Change (pre-sandy) Profile Shoreline Volume Avg.Volume Cell Net Volume Number Change Change Change Distance Change 8th Street Jetty (feet) (yds 3 /ft) (yds 3 /ft) (feet) (yds 3 ) AV AV AV AV AV AV AV AV AV AV ,360-9, ,016-28, ,057-47, ,115-74, , , , , , , , , , , , , , ,616 Total Volume Change for Oceanfront Beaches in cubic yards = -450,616 Table 2 above shows the annual change from 2012 just prior to Sandy s impact to December One year following Sandy the Borough s shoreline remained at a net loss of 450,616 CY of sand. Losses persisted across the entire Borough but the most significant was at the south end where natural recovery was slowed by repeated storm events. Despite USACE efforts the northend beaches have not fully recovered as Saturn and repeated storm events combined to erode the project sand. Sandy stripped approximately 440,000 CY of sand from the Borough s oceanfront shoreline, the recent surveys show the Borough s losses from Sandy still persist a year later. Individual Site Review: This section describes the changes documented at each of the cross section locations. In general, for 2013, the summer season was one of significant sand accumulation recovering much of the losses suffered from

7 previous storm events. The USACE completed a project in early winter 2013 to restore storm damage from Sandy along the engineered beach. Winter storm Saturn impacted the shoreline immediately following the project s completion. Losses to the engineered beach and southern shoreline were significant but the dune system remained largely intact. Natural sand recovery in spring and summer restored much of the damage caused by Saturn and Sandy along the southern beaches. Unfortunately, an early event in October with sustained onshore winds lasting 72 hours had eroded much of the gains at the north end seen in September by the final survey for 2013 in December. AV-9 - Ninth Street Following Sandy the USACE initiated an emergency maintenance project on the northern beaches based on erosion suffered during Hurricane Irene and Sandy. The beach elevation and berm width were restored to the design template with the addition of yds 3 /ft. of sand. No sand was added to the dune system during the project. Following the project s completion winter storm Saturn impacted the Avalon shoreline on March 5, The storm waves cut into the the project beach berm reduced the width by about 100 feet and scoured the nearshore. The upper beach and dune remained intact as the storm s wave energy was absorbed on the project berm. As a more mild weather pattern developed during the spring sand moved landward to form a shallow platform nearshore with sand moving onshore. The summer wave climate was favorable for natural summer beach building, sand from nearshore pushed higher up the beachface slope to restore a wider, higher summer recreational beach berm. Natural recovery did not restore all the USACE project berm losses but provided ample recreational space for summer patrons and enhanced storm protection for the dune system. Seasonal variations in elevation and width occurred along the beach berm but the dunes system remained stable to slightly accretional. Throughout the year the offshore slope lost sand as sand moved cross-shore towards the beach or was swept offshore by inlet tidal currents. Despite the influx of sand from the USACE project the 9 th street beach remained yds. 3 /ft. of sand below the pre-sandy conditions of September Although sand was added to the dune slope through aeolian processes moderate net sand deficits remained on the dune toe, beach berm and nearshore slope following Sandy while the shoreline position (zero datum) remained stable. 5

8 1a. February 28, b. March 7, c. December 11, Photographs 1a to 1c. 9 th Street view to the south. Photograph 1a shows the beach and seaward dune slope following the USACE project. The beach is wider and higher in elevation with the berm crest 150 feet seaward of the dune toe. View 1b is the same view toward the south taken following winter storm Saturn. The beach is narrower and lower in elevation with the wet dry line at the seaward dune toe. Although wave runup reached the toe no damage was done as the storm wave energy was absorbed by the wider project beach. Aeolian sand transport driven by the storm s high winds partially buried and coated the dune vegetation. View 1c By December sand accumulated along the dune fence installed for the summer season. The dry beach remained relatively narrow with the loss of the summer berm during an October storm.

9 Figure 1. At 9 th Street the 5 surveys show the changes since 4 th quarter This site received fill material prior to 1 st quarter 2013; however, much of the added sand was quickly removed during winter storm Saturn. Summer 2013 brought with it an accretional trend as the berm and beachface gained sand. Unfortunately a storm in early October removed much of the gains from the summer months. 7

10 Figure 2. At 9 th Street the two annual surveys above show the recovery to conditions prior to Hurricane Sandy. Overall this site s net sand volume remained yds 3 /ft. below pre Sandy conditions while the shoreline advanced 6 feet since September This site is partially sheltered by the 8 th Street Jetty protecting the beach from direct northeast wave approach, retains a modest beach width and provides protection and stability for the dune. 8

11 AV-12 - Twelfth Street Hurricane Sandy s storm waves caused significant beach and foredune erosion and scoured a deep trough nearshore at 12 th Street. In response the USACE completed an emergency maintenance project by February The project placed yds 3 /ft. of sand on the site, restored the beach design template constructed a berm that extended seaward approximately 100 feet from the seaward dune toe at elevation 8 feet NAVD88 and filled in the nearshore trough. No sand was added to the dune. Immediately following the project winter storm Saturn struck the Jersey shoreline on March 5, The storm severely eroded the project beach, essentially removed the beach berm back to nearly post Sandy conditions. Sand was transferred offshore during the storm that reduced the net profile losses to yds 3 /ft. of sand. During the spring and summer seasons weather conditions favored natural beach building processes. By September much of the project beach had recovered naturally as sand moved landward to the nearshore and onshore building a recreational beach berm for the summer season. Unfortunately, the October 10 th event with its persistent onshore winds generated wave conditions that scoured away the summer berm and nearshore gains. As designed the beach absorbed the wave energy and protected the seaward dune slope from erosion. In the year following Sandy the foredune development, beach berm elevation and width have not recovered. By December 2013 the beachface and nearshore slope had recovered approximately half the sand lost during Sandy but there remained a net deficit of yds 3 /ft. of sand despite the USACE project and natural recovery during the summer. 9

12 2a. February 28, b. March 7, 2013 Photographs 2a to 2c. 12 th Street Views to the south. Photograph 2a shows the beach south of the pedestrian entry shortly following the USACE project. No dune fence was yet installed but the project beach berm was already scarped from the winter wave climate. View 2b taken immediately following Saturn looking south along the same perspective. The project beach berm was overwashed and flattened as wave run up reached the seaward dune toe. Storm wave energy was absorbed by the project beach that limited damage to the seaward dune slope. View 2c shows that by December much of the natural summer recovery eroded during an early October storm event. Wave propagation and energy was attenuated by the summer berm that protected the dune toe and upper beach from erosion. Summer sand accumulation remained in place along the installed fence at the dune toe. 2c. December 11,

13 Figure 3. Fill material was deposited here at 12 th Street prior to the first quarter survey of 2013; unfortunately winter storm Saturn removed much of the added sand. Favorable summer weather patterns resulted in natural recovery and the berm and beachface recovered somewhat. However, by December 2013 the beach was back to nearly what it was post-sandy as a result of a winter storm which removed much of the summer accretions. 11

14 Figure 4. The two annual surveys above show the recovery at 12 th Street since Hurricane Sandy. This site has yet to recover to what it was pre-sandy. The overall volume change is a net loss of yds 3 /ft. of sand and a loss of 22 feet of shoreline. 12

15 AV-17 - Seventeenth Street The profile is located at the southern terminus of a rock revetment which continues north to 8 th Street. Rocks were fully exposed in 1987 prior to the initial beach restoration effort. The revetment has been exposed once after a northeast storm in March Following Hurricane Sandy, the beach berm was severely eroded with a modest scarp in the seaward dune slope but the rocks remained buried. The CRC conducted a detailed survey of the dune system south of 17 th Street where a crest elevation of just less than 14 feet NAVD88 was minimally sufficient to protect the properties landward of this segment from serious breaching and waveinduced damages. The study results included a suggestion to raise the low-lying dune crest segment to 18.0 feet NAVD88 elevation to match the adjoining dune crest elevation during the next maintenance nourishment cycle. This was accomplished during the spring 2013 USACE nourishment cycle. Early in 2013 the USACE emergency maintenance project placed yds 3 /ft. of sand on this beach prior to the 1 st quarter survey conducted on February 28, A large reserve of sand was placed along the berm here that was subsequently eroded during Saturn. Some sand also appears to have been pushed up onto the seaward dune slope enhancing the seaward dune crest elevation and seaward slope. The nearshore slope suffered significant scouring losing a wedge of sand up to 3 feet thick during Saturn with a net loss of yds 3 /ft. of sand. Losses would have been higher if not for the development of a large offshore sand bar near the profile limits that offset onshore and nearshore losses. Over the spring and summer a large volume of sand moved onshore and into the region driven by the prevailing southerly wave climate and winds adding yds 3 /ft. of sand to the profile. Natural beach building processes had restored a wider recreational beach berm by the end of summer while additional sand added to the nearshore formed a shallow platform that extended feet seaward of the shoreline. This period of natural recovery was short lived as 72 hours of strong onshore winds generated storm waves that scoured the nearshore and eroded the summer beach and berm. By December s 4 th quarter survey the beach width was cut landward 100 feet and the profile lost yds 3 /ft. of sand. The net sand recovery from Sandy was almost complete with a minor volume loss of just 0.67 yds 3 /ft. of sand remaining from before the storm to December2013. Recovery was limited to the beachface, the seaward dune crest and slope and offshore sand bar. The overall beach berm width was still 75 feet narrower than prior to Sandy following several storm events in

16 3a. February 28, b. March 7, 2013 Photographs 3a to 3c. 17 th Street, view to the south. Photograph 3a taken Feb. 28, 2013 during the 1 st quarter s survey showed the post USACE project beach and dune conditions. The dune, beach width and elevation were restored but no fence or plants installed. View 3b shows the conditions immediately following Saturn. The project berm width has been reduced and overwashed to the seaward dune toe. Storm wave energy was absorbed by the project beach that protected the seaward dune slope. The storms strong winds blew sand inland frosting the seaward dune slope with fresh aeolian sand. 3c. December 11, 2013 View 3c By December 11 th dune fence was installed along the seaward toe trapping sand to form a new foredune ridge. Dune grasses flourish in the distance but no plants had been installed along the seaward slope at 17 th Street. 14

17 Figure 5. The five surveys above show the activity at 17 th Street since December Fill material was added here in January of 2013 and subsequently removed two months later as a result of winter storm Saturn. There was some transport back to the berm and beachface by September 2013; but by December 2013 the beach configuration was nearly back to what it was in both the post-sandy and post-saturn configurations. 15

18 Figure 6. The two annual surveys above show the recovery at 17 th Street since Hurricane Sandy. The shoreline advanced 33 feet while the net volume change was a minimal loss of yds 3 /ft. of sand. Sand added to the seaward dune slope and bar offset the losses to the berm and nearshore slope. 16

19 AV-23 - Twenty Third Street The 23 rd Street cross section is located seaward of the Avalon boardwalk at the southern end of the engineered beach and federal project. Hurricane Sandy s storm waves cut a scour trough near shore, eroded the beach and cut into the seaward dune slope that formed an 8 foot vertical scarp. As part of the federal project this site received sand during the USACE emergency maintenance project with yds 3 /ft. of sand added to the site. The 1 st quarter survey in 2013 conducted following the project showed the beach berm width extended 100 feet seaward of the dune toe at elevation 7.5 NAVD88 with sand added to the dune to restore the seaward slope. Unfortunately, winter storm Saturn followed on March 5 and removed nearly 80 feet of beach width and yds 3 /ft. or nearly half the sand placed during the USACE project. During the spring and summer landward cross-shore sediment transport moved sand towards the beach and by September a modest summer beach berm had developed. Despite the modest onshore and nearshore sand volume gains the overall profile continued to lose sand for a net loss of yds 3 /ft. of sand by September. The offshore bar faded as sand moved landward and likely north driven by the summer s prevailing southerly winds and wave fetch. During the fall the erosional trend continued as the summer berm was cut landward and the nearshore slope scoured for a net loss of yds 3 /ft. of sand removed by December. Post-Sandy recovery at this site has been limited to restoration of the seaward dune slope and modest beach recovery. Despite the USACE emergency maintenance project that restored the design template the berm elevation, beach width and nearshore slope remain at a net deficit of yds 3 /ft. of sand a year following Sandy. Winter storm Saturn and early fall events combined to erode much of the project gains. These storms follow a recent erosional trend since 2009, a period of increased storm frequency and intensity, that has increased erosional rates along this section of shoreline. 17

20 4a. February 28, b. March 7, 2013 Photographs 4a to 4c. 23 rd Street, views to the north. Photograph 4a shows the beach following the USACE project in late February. The beach is wider and berm elevation elevated to cover most of the storm outfall pipe. View 4b followed winter storm Saturn, the dunes were protected by the wider and higher project beaches but the storm waves eroded the project berm landward 75 feet and flattened the slope, which exposed more of the outfall pipe. View 4c shows dune fence was installed and sand accumulation along the landward fence line. The beach remained relatively narrow after modest summer recovery on the beach rapidly eroded during the fall. 4c. December 11,

21 Figure 7. The five surveys above show the activity at 23 rd Street since December Fill material was added here in January Two months later winter storm Saturn moved through and removed much of the sand from the berm and transported it offshore. There was some recovery in summer and fall as favorable weather patterns resulted in natural recovery. However, by December 2013 the beach was nearly back to what it was post-sandy. 19

22 Figure 8. The two annual surveys above show the recovery at 23 rd Street since Hurricane Sandy. The shoreline retreated -6 feet and the beach lost yds 3 /ft. of sand. Sand was lost from the berm, beachface, and nearshore slope. 20

23 AV-28 - Twenty Eighth Street The 28 th Street location is situated along the barrier island where the shoreline curves slightly to the west altering the angle or approach for northeast waves, which results in a lower impact from the erosion that plagues the beaches to the north. This site also benefits from predominant longshore current transport of sand south from the north end erosional beaches. Although included in the federal project scope this beach is typically located near the taper end of the USACE maintenance projects. This trend continued for the 2013 USACE emergency maintenance project where the taper was between 23 rd and 28 th Street as a result no sand was placed here directly during the recent project. Hurricane Sandy reached the seaward toe of the dunes at 28 th Street, flattened the beach and dragged material offshore where a large bar had developed by late November This sand slowly moved landward until late spring and early summer when weather patterns developed that favored landward cross-shore transport. The summer wave climate and winds moved sand onshore and by September a wide beach berm was reestablished through natural beach building processes. This wider dry berm provided ample recreational beach for summer beach patrons at this popular summer destination beach. Volume changes were minimal during the first three quarters of 2013 as cross-shore sediment transport dominated the processes moving sand between the onshore and offshore regions. Storm waves generated by 72 hours of sustained onshore winds around October 10 th scoured a deep trough nearshore and flattened the beach berm. Some sand was transferred to the offshore bar system but yds 3 /ft. of sand was swept away form the site for a net annual loss. Compared to conditions just prior to Sandy the beach remains at a net deficit of yds 3 /ft. of sand mostly as a result of the flattened berm and deep scour trough cut in the fall event. 21

24 5a. March 1, b. March 7, c. December, 11, Photographs 5a to 5c. 28 th Street, views to the south. Photograph 5a The USACE project tapered into to existing beach conditions just north of this location, no sand was placed here. The beach is lower in elevation and narrow 5 months post Sandy. View 5b Shows conditions immediately following winter storm Saturn. Storm waves overwashed the beach pushed the wrack line to the seaward dune toe. Wave run up reached the dune toe but little serious damage was done. Aeolian transport carried sand into the dune frosting the vegetation. View 5c shows that by December 11, 2013 the beach had accumulated sand naturally over the spring and summer, raised the elevation and extended the beach berm seaward. The dune accumulated sand along the recently installed fence restoring the seaward dune slope.

25 Figure 9 The five surveys above show the activity at 28 th Street since December Twenty Eighth Street did not receive fill material from the January 2013 fill project. By September 2013 sand had been transported to the dry beach via cross-shore transport and formed a berm. By December 2013 a two tiered berm formed and the offshore bar had begun to migrate landward. 23

26 Figure 10. The two annual surveys above show the recovery at 28 th Street since Hurricane Sandy. The shoreline advanced 33 feet while the net volume change was a loss of yds 3 /ft. of sand. Despite the accretional trends in the spring and summer of 2013 this site has still not recovered the sand volume it lost as a result of Hurricane Sandy. 24

27 AV-35 - Thirty Fifth Street Sand has naturally accreted on this section of the Borough s oceanfront due to longshore transport of sand that has been placed on the erosional beaches to the north starting in Multiple maintenance iterations leading to the 2002 Federal project introduced a large volume of sand added to this shoreline. This location continues to benefit from the influx of sand derived from erosion of the engineered beach immediately following significant beach nourishment projects. Today the well-established dune system extends seaward of the street end some 600 feet and the shoreline nearly 1,000 feet, a well-developed shore protection feature for oceanfront properties and infrastructure. Storm waves and surge from Hurricane Sandy flattened the beach and cut into the seaward dune slope leaving up to a 4 foot scarp. Located south of the federal project no sand was placed here during the USACE emergency maintenance project. Sand began to move onshore during the spring and continued over the summer months. Aeolian transport carried sand to the dune scarp where it accumulated and restored the seaward dune slope. A large influx of sand added yds 3 /ft. of material to the profile that occurred prior to the spring survey as sand moved south from the project beaches following Saturn. Landward cross-shore sediment transport dominated over the summer as the prevailing gentle wave climate and winds pushed sand onshore. The offshore bar moved landward towards the beach pushed onshore to form a wider, higher beach berm and fill the nearshore trough formed during Sandy. During the fall, waves scoured the nearshore seafloor and carried the sand offshore to form a wide sand bar near the profile limits. The beach berm remained relatively intact with a small sand ridge along the shoreline ready to move onshore. This site has essentially recovered from Sandy with a net gain of 2.79 yds 3 /ft. of sand since September The December beach configuration mimics the pre-sandy conditions with only a modest loss on the seaward dune slope. Offshore a large sand bar developed near the profile limits that resulted in the net sand volume gain. 25

28 6a. March, 1, b. March 7, 2013 Photographs 6a to 6c. 35 th Street, views to the north. Photograph 6a shows the beach and dune toe conditions on March 1 a few days before Saturn impacted the coast. The beach berm was relatively narrow following previous storm events. View 6b followed the impact of Saturn. The broad, flat beach was generated as large waves over washed the beach to the dune toe, cut a minor scarp on the seaward edge of the foredune. 6c. December 12, 2013 View 6c was taken in December 2013 following natural summer and spring beach building. Sand has migrated onto the beach raised the beach elevation and extended the beach berm seaward 100 feet. Fence installed along the seaward dune toe accumulated sand and restored the seaward slope. 26

29 Figure 11. The five surveys above show the activity at 35 th Street since December Hurricane Sandy reduced the entire beach to a gently seaward sloping planar surface and a huge bar developed offshore. Over the past 12 months a large volume of sand has moved landward and welded itself onto the dry beach. 27

30 Figure 12. The two annual surveys above show the recovery at 35 th Street since Hurricane Sandy. The shoreline advanced 71 feet and there was a net gain of 2.79 yds 3 /ft. of sand. Sand was added to the dry beach as a bar was transported landward and welded itself onto the beachface forming a ridge and runnel system. Losses to the nearshore slope were offset by gains to the offshore slope. 28

31 AV-44 - Forty Fourth Street Located in the heart of the famous Avalon High Dune Area comprised of just over 100 acres of the finest coastal dunes along the New Jersey shoreline, this site has gained sand over the last two decades of monitoring. This site has a 1,000-foot wide zone of dunes between the 50-foot elevation primary dune along Dune Drive that is populated by multiple ridges of lower elevation because they accumulated and expanded quickly over many decades as the beach accreted seaward. The impact of Hurricane Sandy was a 2.70 yds 3 /ft. net loss in sand volume that was the second least along the Avalon coast. Sandy s waves washed inland among these ridges where sand transported from the beach was deposited as a fan into the interior. The seaward edge of the foredune was removed and the beach berm was graded flat and sand was moved seaward as well. Sand moved landward in late spring and pushed onshore by the summer wave climate and winds forming a new wider and higher beach berm. The net gain was yds 3 /ft. of sand. Storm waves in the fall cut into the beachface with sand transferred seaward to the profile limits or beyond for a modest net loss of 4.25 yds 3 /ft. of sand. Recovery from Sandy has been limited as the site remains yds 3 /ft. of sand below the pre-sandy conditions. Losses remain along the berm and in the scour trough nearshore while sand resides offshore at and beyond the profile limits. Sand shed from the most recent USACE project should eventually move into this region and restore the profile losses. 29

32 7a. March 1, b. August 29, 2011 Photographs 7a to 7c. 44 th Street, views to the north. Photograph 7a is a view northeast across the foredune area looking over the expansive seaward dune slope coverage along this wide beach. View 7b is the view following Saturn the beach was over washed and flattened by the storm waves with run up debris pushed onto the seaward dune slope. 7c. December 12, 2013 View 7c shows conditions in December 2013 with the same view as the post-storm photo above. A dune fence was installed along the dune scarp ridge to restore the slope. Dune grass has propagated seaward across the seaward slope to the toe. Sand accumulated onshore over the spring and summer season building a wider and higher beach berm as natural recovery continued in this highly accretional region. 30

33 Figure 13. The five surveys above show the activity at 44 th Street since December Hurricane Sandy leveled the berm and produced a broad, flat surface which sloped gently out to the nearshore. Via cross-shore transport sand has slowly migrated landward over the past 12 months. By September 2013 the berm had recovered to nearly what it was prior to Hurricane Sandy. 31

34 Figure 14. The two annual surveys above show the recovery at 44 th Street since Hurricane Sandy. The shoreline retreated -74 feet and the net volume change was a loss of yds 3 /ft. of sand. Sand lost from the berm and offshore slope has yet to recover. 32

35 AV-58 - Fifty Eighth Street This site lies at the southern margin of the Avalon high dune area. Development south of 58 th Street extends east of Dune Drive along numbered streets toward the beach. The annual changes prior to Sandy were long term accretional trends typical of low wave energy. The impact of Hurricane Sandy was to take yds 3 /ft. from the beach by stripping away the berm, scouring the immediate offshore to a lower elevation. Sand was transported over the considerable foredune that had been building for several years on the toe of the primary dune, filling in the trough between the primary dune and the remainder of the foredune. Since the foredune was originally at elevation 10.0 and had a 40-foot base width, it absorbed most of the storm wave energy. There was no erosion on the primary dune and only a dozen feet of retreat at the foredune s seaward slope. Over the spring and summer month s sand slowly moved landward driven by favorable weather and wave conditions. The gentle summer wave climate pushed sand onshore to form a higher, wider berm ridge with a steeper beachface slope by September. This site received the largest influx of sand during the spring and summer for a combined gain of yds 3 /ft. of sand. During the fall storm waves eroded the beachface and nearshore transporting sand offshore to form a new sand bar near the profile limits. A net loss of yds 3 /ft. of sand resulted this fall. Recovery from Sandy was limited, sand accumulated along the seaward slope but the overall beach width remained 60 feet landward than prior to Sandy. A deeper trough offshore accounted for the remaining losses while further offshore bar formation near the profile limits partially offset these losses for a net loss of yds 3 /ft of sand from conditions before Sandy to December 2013 or a net gain of just 6.1 yds 3 /ft. of sand since Sandy. 33

36 8a. March 1, b. March 7, 2013 Photographs 8a to 8c. 58 th Street, views to the north along the seaward dune toe. Photograph 8a illustrates the broad expanse of the dry beach that extends seaward from the edge of the dune grass new foredune growth has slowly expanded seaward onto the beach. View 8b is a view looking north along the dune toe immediately following Saturn. The waves eroded all the mid-borough beaches to a very low gradient surface erasing all topographic features previously present. Waves overwashed the modest foredune development as the wet sand and wrack debris line extended well into the foredunes. 8c. December 12, View 8c shows the beach in December following summer and spring natural recovery built a wider and higher beach berm. A dune fence was installed along the previous dune scarp to collect aeolian sand while grass has propagated seaward to the toe.

37 Figure 15. The five surveys above show the activity at 58 th Street since December A major bar appeared offshore in December 2012 following Hurricane Sandy. Since that time sand has migrated landward via cross-shore transport and welded onto the beachface and berm. 35

38 Figure 16. The two annual surveys above show the recovery at 58 th Street since Hurricane Sandy. The shoreline retreated -44 feet and the net volume change was a loss of yds 3 /ft. of sand. The foredune that existed prior to Hurricane Sandy was overwashed and sand was transported landward, filling in the trough that existed between it and the primary dune. A major bar has appeared offshore and if it moves landward, will supply a large volume of sand to the beach. 36

39 AV-70 - Seventieth Street The 70th Street dune cross section is 250 feet wide with a crest elevation of 16-feet NAVD88 seaward of the development. This current dune configuration expanded seaward since 1998 by aeolian processes derived from sand on the wide dry recreational beach area. Repeated fencing installation over the past 15 years has driven the seaward expansion of the dune. Hurricane Sandy stripped the berm from the beach removing a large volume of sand that did not wash inland into the dunes. This material likely moved south along the shoreline. The December survey showed that yds 3 /ft. were taken, the highest sand volume along the Avalon shoreline. A deep offshore trough had developed, but a bar also formed far offshore at a 1,500-foot distance from the reference position. Since Sandy natural recovery has been modest. Winter storm Saturn removed another yds 3 /ft. of sand from the beach and nearshore. Sand moved landward during the spring and summer and slowly moved onshore pushed higher up the beachface by the summer wave climate to reestablish a wider beach berm. Wind driven sand accumulated along the seaward dune slope developing a new foredune ridge. The net spring summer natural gain was impressive at 34 yds 3 /ft. of sand essentially recovering all the losses from Saturn. During the fall sand eroded again from the beachface and was carried seaward by storm waves generated by 72 hours of onshore winds in October. Net natural recovery from Sandy was limited this year, of the yds 3 /ft. of sand removed just 4.37 yds 3 /ft. of sand had returned to the beach focused along the seaward dune toe and on the upper beach. The overall beach width remains 60 feet landward of the its position prior to Sandy with a wedge of sand removed from the berm across the nearshore to about 600 feet seaward of the shoreline. A small bar deposit near the offshore limits of the profile suggest sand may reside beyond the survey limits that may slowly return to the shoreline over time under favorable conditions. As of December 2013 the site remained yds 3 /ft. of sand below its pre-sandy condition. 37

40 9a. March 1, b. March 7, 2013 Photographs 9a to 9c. 70 th Street, views to the north. Photograph 9a shows the dune toe and beach prior to Saturn natural recovery since Sandy had slowly added sand to the beach but the beach remained relatively flat. View 9b shows an identical view immediately following Saturn wave run up reached the fencing with the wet and wrack debris line at the seaward toe but little serious dune damage occurred. The beach absorbed most of the storm wave energy that flattened the beach leaving just a narrow strip of sand between the waves and dune toe. 9c. December 12, View 9c shows natural recovery over the spring and summer had restored the wide dry beaches typical in this region. Dune fence had been installed along the seaward dune toe to capture sand and restore the slope.

41 Figure 17. The five surveys above show the activity at 70 th Street since December The dune and berm suffered minor damage as a result of Hurricane Sandy with the lost sand being transported offshore and south. Both the dune and berm had recovered most of the lost sand by September 2013 when the summer berm was at its highest and widest. 39

42 Figure 18. The two annual surveys above show the recovery at 70 th Street since Hurricane Sandy is not complete. The shoreline has retreated 60 feet and the net volume change was a loss of yds 3 /ft. of sand. Losses to the berm, beachface, and nearshore slope, account for the majority of the losses. 40

43 AV-78 - Seventy Eighth Street This site is located just two blocks from the boundary with Stone Harbor in front of the Avalon hotel district. The dune is 170 feet wide and rises to an elevation of 18 feet. This site has periodically received sand as part of the federal project for southern Avalon and Stone Harbor. Hurricane Sandy cut yds 3 /ft. from the beach as the berm was erased with a minor cut into the toe of the seaward dune slope. A deep trough developed offshore with an impressive bar forming well seaward. Winter storm Saturn removed an additional yds 3 /ft. of sand from the beach and nearshore. Sand from the bar feature moved slowly landward eventually adding its volume to the beach as conditions for natural recovery prevailed in late spring and summer. During the spring and summer sand moved onshore pushed up the beachface by the gentle wave climate to reestablish a wider and higher beach berm. Recovery was aided by the completion of an emergency maintenance project for Stone Harbor this summer that tapered into the shoreline just south of this site with runoff from the project spilling into this location adding to the sand volume. The net volume gain for the spring and summer was yds 3 /ft. of sand. Recovery from Sandy was hindered by winter storm Saturn but assisted by the USACE project in Stone Harbor. Sand accumulated along the seaward dune slope and the summer berm development restored about half of the losses to the beach. The nearshore seafloor has yet to fully recover but a large wedge of sand is located offshore that offset these losses. The spring and summer recovery has brought this site to within 7.64 yds 3 /ft. of its net pre-sandy sand volume. 41

44 10a. March 1, b. March 7, 2013 Photographs 10a to 10c. 78 th Street, views to the south. Photograph 10a shows the dune toe and beach on March 1 st prior to the arrival of Saturn and less than five months following Sandy. The beach is still relatively narrow and low in profile dune recovery is slow but the fence was not yet installed. View 10b shows the post-saturn beach and dune conditions. Only a narrow strip of sand remained as a nearly horizontal, very flat surface extending from the dune toe, to the water s edge. Storm wave run up reached the seaward dune slope and removed most of the sand that had accumulated post- Sandy. 10c. December 12, View 10c was taken from the dune toe in December following spring and summer natural recovery. Sand moved onshore restored the wider beach and elevated the recreational berm. Dune fence was installed and accumulated sand along the toe to restore the seaward dune slope.

45 Figure 19.. The five surveys above show the activity at 78 th Street since December Following Sandy the beach continued to erode and the nearshore was scoured by Saturn. Natural recover slowly occurred during the spring. During the summer sand moved cross-shore to the beach from the offshore bar restoring a wider recreational beach and berm. By the end of fall early season storms eroded the berm width and scoured the nearshore, sand was transferred offshore. 43

46 Figure 20. The two annual surveys above show the recovery at 78 th Street since Hurricane Sandy. The shoreline advance 4 feet while yds 3 /ft. of sand was lost. Sand was lost from the berm, beachface, nearshore slope, and from the bar. Losses were offset by small gains to the offshore slope and seaward dune slope. 44

47 SUMMARY OF AVALON S OCEANFRONT BEACHES: Hurricane Sandy caused significant erosion along the beaches in Avalon which absorbed most of the storm wave energy. There were no significant breaches to the dune system. Only two minor zones of overwash were observed and both documented for remediation during the spring of Overall the storm eroded 440,000 CY of sand from the Borough s oceanfront shoreline. In response the USACE completed an emergency maintenance project on February 3 rd placing a reported 336,359 CY of sand along the engineered beach. On March 5, 2013 winter northeast storm Saturn moved up the New Jersey coast and caused significant beach erosion. The storm stripped sand from the north end beaches placed by the USACE just weeks before the storm. Storm waves cut into the berm and flattened the slope back to the seaward dune toe. Borough wide the storm removed 350,832 CY of sand from the surveyed regions. The 2013 USACE maintenance project from the jetty south to the 28th street lost 94,942 CY of sand from the project region including offshore where some sand was deposited, when limiting losses to onshore changes the volume increased to 112,321 CY or approximately 33% of the placed sand volume. In late spring through the summer weather patterns and wave climate favored natural recovery and beach building processes. Sand moved onshore driven by the predominant southerly winds and waves. The gentle summer waves pushed the sand up the beachface restoring the summer recreational beach and berm. From late March through September the oceanfront beaches gained 413,220 CY of sand through natural processes. Beach widths advanced seaward and the onshore and nearshore elevations increased with the additional sand aeolian transport effectively moved sand to the seaward dune toe where it accumulated and restored the seaward slopes eroded by the recent storm events. Unfortunately, the natural onshore gains quickly eroded on October 10 th during a 72 hour period of strong onshore winds and waves that flattened the summer berm and scoured the nearshore seafloor. Sand was transported offshore and longshore with the angle of approach impacting the north end beaches extensively. The fourth quarter survey conducted in early December revealed a net loss of 309,215 CY of sand from the Borough s oceanfront shoreline. Hurricane Sandy impacted the entire community for a net loss of 440,000 CY of sand from the Borough s shoreline. A comparison between the December 2013 fourth quarter survey and pre-sandy conditions in late September 2012 show a net loss of 450,616 CY of sand. Despite the USACE project and robust natural summer sand recovery the continued frequency and intensity of storms in 2013 offset these gains and prevented recovery to Pre-Sandy conditions. The net volume change over 2013 following Sandy was insignificant but the volume of sand in motion and added was impressive. The cumulative impact from storm events in 2013 stripped 660,047 CY of sand from the oceanfront shoreline during multiple episodes while the USACE added 336,359 CY followed by 413,220 CY of natural recovery in the spring and summer along the shoreline. Dune features were rebuilt or have recovered naturally from Sandy s damage but the beach and nearshore seafloor conditions have not recovered to their pre- Sandy configuration or sand volume as a result of the frequency of storm events in Engineered Beach 6-Month Review Initial beach nourishment at the north end of Avalon began in 1987 with a State/Local sponsored project with multiple maintenance intervals conducted by the Borough. In 2002 the USACE constructed a federal project with the Borough and State providing additional sand hydraulically pumped onto the beach in 2006 and Trucks hauled in quarry sand in 2007 and 2009 to restore recreational access between 10 th and 17 th Streets and 45

48 again in 2010 to restore the dune between 17 th and 21 st Streets followed hydraulic sand pumping in June of In 2011, a federal maintenance beach replenishment project placed 450,000 cy of sand on northern beaches. A back-passing program was implemented as a pilot project in 2006 to recycle 58,000 cy of sand hauled to the northern shoreline from surplus material obtained between 31 st and 70 th Streets. This was repeated again in 2012 under USACE authorization when 63,956 cubic yards of sand were hauled from the same source beaches to the zone between 12 th and 21 st Streets. Finally during the winter the US Army Corps of Engineers (USACE) completed an emergency maintenance project on the northern beaches based on erosion suffered during Hurricane Irene and Sandy. The project was eligible for Flood Control and Coastal Emergency funds under Public Law and in response to P.L Disaster Relief Appropriations Act the project beach was eligible for restoration to design template. The section below is a 6-month review of this most recent effort. The Coastal Research Center (CRC) completed a 6 month performance assessment of the 2013 beach nourishment effort by the USACE. In June 2013 the CRC survey crew conducted a complete survey of the Avalon engineered beach. The 6 month post fill survey dataset collected by the CRC, and the immediate post fill dataset collected by Great Lakes Dock and Dredge were analyzed in ArcGIS software to generate digital elevation models (DEM) of the area. A volume change analysis was performed to determine the volume of sand lost or gained within the project area over the initial 6 month time period following construction. Digital Elevation Model The survey data were analyzed in ArcGIS software where a continuous, 3-dimensional DEM surface was generated for the immediate after dredge conditions and 6 month conditions by interpolating the real time kinematic GPS and transit elevation data between multiple survey lines (figures 21 & 22). The DEMs are color coded with the cooler blue colors representing lower elevations and warmer red colors representing higher elevations. Contour lines were created at two foot increments for additional visualization of elevation change throughout the area of study. All elevation units are in US survey feet and are referenced to the North American Vertical Datum 1988 (NAVD88) survey datum. After the beach nourishment project, February 3rd, 2013, a distinct dune and large beach are evident in the DEM (figure 21). Six months later the large beachface has eroded and much of the area that was a beach was below 0ft NAVD88 and submerged at high tide (figure 22). The dune remained intact but susceptible to minor storm events due to the loss of beach. 46

49 Figure 21, Cooler blue colors represent lower elevations, and warmer red colors represent higher elevations. Contour intervals are at 2ft intervals. Elevation units are in NAVD88. A large dune is evident between 17th St. and 9th St.. The wide flat beach was built at an approximate elevation of 8ft and tapers into the existing beach between 24th and 25th St. 47

50 Figure 21, The large wide project beach eroded during the initial 6 months following construction leaving the large dune susceptible to minor storm events. Winter storm Saturn had an immediate impact on the beach s stability striking the NJ coast within weeks of the project s completion. 48

51 Volume Change Sand volume change was determined throughout the study area by comparing the immediate post fill, February 2013 and the June 2013 DEMs and deriving an elevation change grid (figure 23) that represents elevation change in 2 ft. increments with the darker green colors represent areas of greater elevation increase and the darker red colors represent areas of greater elevation decrease. A total of -277,900 cubic yards of sand was lost from the study area. A maximum elevation loss of ft. occurred where the beachface eroded from an elevation of approximately 8 ft. down to -2 ft. A maximum elevation gain of 5.7 ft. feet was seen in small areas over the 6-month study period. The significant areas of loss occurred across the entire engineered beachface which is evident in the elevation change map as well as the 4 cross sections generated from the datasets (figures 25-28) 49

52 Figure 23, Elevation change from immediate post fill conditions (February, 2013) to 6 months after the beach nourishment project (June, 2013). The darker green colors represent areas of greater elevation increase and the darker read colors represent areas of greater elevation decrease. A total of -277,900 cubic yards of sand was lost from the study area in the first 6-months. The majority of sand was lost from the as built beach face which eroded from 8ft to 0ft or less. 50

53 Figure 24, Transect position reference map. The above map depicts the locations of the cross sections selected for this report. 51