The paragraph below is included yet again to provide information for the reader on the ACOE beach restoration work concluded in April 2005.

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1 Mayor Carl Schupp and Council May 28, 2009 Borough of Cape May Point PO Box 490 Cape May Point, NJ Introduction: The Richard Stockton College Coastal Research Center conducted a series of nine cross section surveys of the municipal beach on May 5 and 6, These were compared to previous studies done April 2007 and April This work completes an annual review of the municipal beaches prior to the tourist season. The 2005 Army Corps of Engineers (ACOE) project was dramatically successful in restoring width to the beaches particularly between Lighthouse and Willdin Avenues. The effectiveness of the project raised the problem of too much sand present at the two early submerged breakwater installation sites at the Lehigh and Willdin Avenue beach cells producing a situation where the low tide shoreline was dangerously close to the concrete breakwater units. Fear of swimming injuries against the massive concrete breakwater units prompted closure of the beaches to swimming for the past several summers. This winter the ACOE came back and modified the project to reduce the sand volume at the two older breakwater cells and place additional sand on ocean-facing beaches and at Lake Avenue beach (where no breakwater units were placed). The plots of the survey data demonstrate the impact of the recent work by the ACOE and its contractors. The nine permanent monitoring survey lines are located at the following sites along the Borough s ocean and bay shorelines. Each cross section is located midway between the rock groins that define each of the beach cells. CMP-0: Lighthouse Avenue CMP-1: Lehigh Ave CMP-2: Willdin Ave CMP-3: Coral Ave CMP-4: Lake Drive CMP-5: Cape Avenue CMP-6: Emerald Avenue CMP-7: Stites Avenue CMP-8: Alexander Avenue The paragraph below is included yet again to provide information for the reader on the ACOE beach restoration work concluded in April The US Army Corps of Engineers (ACOE) experimental project dovetailed with the State and local project that added sufficient gabion rock cages to complete the installation in Cell 5. The State then excavated sand at the toe of the dunes in Cell 6 and installed gabion cages throughout the cell. The Cape May Meadows/Cape May Point Shoreline Protection Project then added over 325,000 cubic yards of sand to the beach between the Cell 1 and Cell 6 (ACOE estimate, communication from J. Bailey Smith, project manager). The ACOE estimate of the total volume of sand placed was 800,673 cy for the entire beach between the WWII bunker and Cell 6 including the offshore scour hole. Their estimate of 140,000 cy for the scour hole fill was subtracted from their 800,673 cy total followed by dividing the distance from the bunker to the first groin by 5 to estimate the sand quantity placed along the Lighthouse 1

2 Avenue beach within Cape May Point at 66,751 cy to get an estimated total of 393,668 cubic yards for the sand volume placed along the same beaches that the CRC surveys for the Borough. The comparison between December 2000 and April 2005 documented a quantity of sand equal to 442,535 cubic yards of sand between the State Park/Cape May Point boundary and Cell 6. This larger sand volume includes the volume necessary to make up losses between December 2000 and conditions present just prior to the ACOE project start. Review of Each of the Beach Cells in Cape May Point: Lighthouse Avenue; Figure 1. Lighthouse Avenue April 2007 in a view toward the northeast toward the WWII bunker. By April 2009 following the ACOE renourishment project, the beach looks nearly the same as in This site has the greatest exposed to Atlantic Ocean waves and the fetch of northeast storms. However, since April 2007 the dune, the upper beach and berm position have not changed, largely because there have been no storms sufficiently powerful to reach the dune. Since 2008 the recent work by the ACOE added yds 3 /ft to the sand volume present and extended the shoreline seaward by 55 feet. The fill material continues offshore into 16 feet of water. Lehigh Avenue; Figure 2. Lehigh Avenue Fall 2006 in a view toward the southwest at the toe of the dune. 2 By April 2009 the fence has been nearly buried and the grass has moved beyond it. The beach is narrower.

3 Lehigh Avenue shares the longest groin in the array of rock structures around the Borough s shoreline. The excess length produces strong eddy currents during peak tidal flow in both ebb and flood directions. There are no submerged structures in this cell. No new sand was added this winter. The shoreline retreated 14 feet and the sand volume declined by yds 3 /ft. No change occurred on the berm or at the toe of the dune built in Lehigh - Willdin Avenues; Figure 3. Lehigh-Willdin Avenues Fall 2006 in a view toward the east at the toe of the dune. By April 2009 the fence has been buried and the grass has colonized the area. Sand was removed from the cell This groin cell contains the early installation of Breakwater units from 1994, which still show on the profile cross-section at the 520-foot distance from the reference point. The 2009 survey documented the continued presence of the breakwater reef in the same location at the same elevation. The ACOE work effort removed yds 3 /ft and produced a 45-foot shoreline retreat creating that additional distance between the bathers and the concrete reef. In addition, the offshore area between the shoreline and the reef structure is deeper by several feet making swimming into the reef less likely. A line of floats fixed at a point about 40 feet landward from the alignment of the reef would be a good warning for the limit of swimming at this and the other breakwater-protected beaches. 3

4 Willdin - Coral Avenues; Figure 4. Willdin Coral Avenues in a view toward the east at the toe of the dune taken in April By April 2009 the fence has been nearly buried and the grass has become better established. Sand was removed by the ACOE to allow bathing. The substantial advance in the shoreline and the berm sand volume documented last year was removed by the ACOE this year yds 3 /ft were removed that pushed the shoreline landward of the 2007 position. This site had the beach nearly at the breakwater reef position last year, but today, the shoreline is 95 feet landward of the 2008 location and 36 feet landward of the 2007 position. Offshore, the water depth is up to 8 feet deeper at the shoreline position shown on the 2008 survey. A line of fixed floats to warn of the limit of swimming is recommended. Coral - Lake Avenues; Figure 5. Coral Avenue April 2008 in a view toward the east at the toe of the dune. By April 2009 the beach is wider due to the ACOE project. Dune grass growth is evident as well. Cell four received yds 3 /ft of new sand on the berm, but lost yds 3 /ft offshore as the seabed became a steeper slope further offshore. There are no hard structures present in this cell and past surveys have documented a faster sand loss rate than in any of the four protected beach cells in Cape May Point. 4

5 Surf - Cape Avenue; Figure 6. Surf Cape Avenue Fall 2006 in a view toward the southwest at the toe of the dune. By April 2009 the fence has been buried and the grass has moved beyond it. The beach is stable. CMP-5 is the site of the Breakwater unit installation as part of the CMP-227 experimental project conducted by the ACOE. The breakwater units were all exposed and remained in place with no additional settling at this profile line s crossing point, during this recent survey. A modest 2.24 yds 3 /ft of new sand appeared as a small foredune since last year and yds 3 /ft of new sand appeared on the berm, likely derived from material bypassing the groin between cells 4 and 5. Offshore the sand shifted from the landward to the seaward sides of the concrete breakwater. This beach has sufficient distance between the zero elevation position and the breakwater units for safe swimming. The depth at the breakwater is 9.2 feet and the distance offshore from the zero elevation is 200 feet. Cape - Pearl Avenues; Figure 7. Cape - Pearl Avenues Fall 2006 in a view toward the east at the toe of the dune. By April 2009 the fence has been buried and the grass has developed a foredune. The beach is a little wider. CMP-6 is where the Double Tee structures were installed as part of the CMP-227 experimental project. Sand buried these structures prior to the placement of the sand on the beach. The 2007 advance in the berm took the cross section configuration nearly back to the post-construction position in In the recent survey the submerged Double Tee units were re-discovered exposed on the seafloor. The profile 5

6 plot shows that sand is banked up against the inner vertical leg of the structure and that the seaward leg stands out of the seabed. This unit was likely exposed in 2007 as well since that line is nearly the same at the location of the Double Tee structure as it was in The survey crew failed to find it in 2008 since it had been buried previously since placement and no one was looking for it. This cell lost 0.86 yds 3 /ft. and the shoreline retreated 5 feet. This is essentially no change since There is no probability of swimmers reaching the submerged Double Tee structures in 11 feet of water 170 feet offshore. Brainard Central Avenues; Figure 8. Brainard Central Avenues Fall 2006 in a view toward the southwest at the beach berm. By April 2009 the beach was substantially wider as sand moved west to this cell. CMP-7 did not receive sand directly from the ACOE beach restoration project. This year the wind added sand across the dune crest onto the back-slope (2.92 yds 3 /ft). The berm accumulated 8.63 yds 3 /ft as the shoreline advanced seaward by 11 feet. This advance and sand increase is less than the amount observed between 2007 and 2008, but provides continuing evidence that sand is moving across the groins into the western two cells. Knox Alexander Avenues; Figure 9. Knox Alexander Avenues Fall 2006 in a view toward the southwest at the crest of the dune. By April 2009 the crest has remained the same, but the beach is 100 feet wider as sand moved west. 6

7 The westernmost cell is CMP-8, positioned between the last two groins. No sand was added at this beach during the 2005 ACOE project either, yet sand continued to move into this cell adding yds 3 /ft to the berm this year. The gain of yds 3 /ft since 2005 is also impressive with a 99-foot wider beach just from natural sand transport around or over the groins between cells. The summary table below compiles the shoreline change information, which is based on the advance seaward or the retreat landward of the zero elevation position on each cross section. This elevation represents the shoreline position; it approximates the proper change horizontally for any shoreline point selected on the beachface subject to daily wave run-up. The unit sand volume computed for the cross section in cubic yards of sand per foot of shoreline is multiplied by the distance between the groins in Cape May Point to arrive at the net volume in the right column. Table 1. Summary of Shoreline and Profile Sand Volume Changes Between April 2008 and May 2009 at the Cape May Point Beaches Profile Shoreline Volume Cell Net Volume Number Change Change Distance Change (feet) (yds 3 /ft) (feet) (yds 3 ) CMP ,817 CMP ,356 CMP * ,796* CMP * ,059* CMP ,190 CMP ,426 CMP CMP ,012 CMP ,543 * sand volume removed Total Volume Change for Cape May Point = 19,166 cu. yds. The US Army Corps of Engineers modified the 2005 project during the past spring. Sand was placed on the State Park and up to the first groin in Cape May Point. That site is defined by CMP-0 at Lighthouse Avenue. The 55-foot shoreline advance is the direct result of the project s sand placement. No sand was put in the second cell at the Catholic Retreat. A modest loss occurred over the past year. Cells 2 and 3 contain the initial concrete breakwater unit installations and each had sand removed by the project s 7

8 contractor. Sand removed was placed in the Lake Drive cell to increase the depleted sand supply. Migration of material to the west has continued, increasing the sediment supply at cells 5, 7 and 8. This year the most sand appeared in cell 8. The four western cells all had significant sand volumes added to the dunes in 2008 as well. The impact of these changes to the degree of safety from collisions by bathers on the submerged breakwater units is as follows: 1. Cells 0 and 1 do not have structures, just steep slopes into deep water with strong tidal currents into and out of Delaware Bay. 2. Cell 2 at Lehigh and Whilldin Avenues now has a 180-foot distance to the breakwater structure compared to 2008 (127 feet). The water is 2 feet deeper between the water s edge and the breakwater units so swimming depths are available this year. The CRC still recommends installing a line of floats indicating the maximum distance for swimming that should be about 30 to 40 feet from the breakwater reef. 3. Cell 3 had the most sand removed to make space available to swim. The 58-foot distance was increased to 150 feet this year and the water depth from the beach to the breakwater is 2 feet greater everywhere in between. The CRC recommends installing a line of floats indicating the maximum distance for swimming that should be about 30 to 40 feet from the breakwater reef. 4. Cell 4 has no structures offshore 5. Cells 5 and 6 contain the newer units and pose no change in swimming risk in 2009 in spite of some sand addition to cell 5. Both reef structures lie in greater than 8 feet of water several hundred feet from the water line at low tide. 6. Cells 7 and 8 beaches are significantly enhanced with much wider berm area and shallower water offshore. Available recreational area and swimming has been substantially improved at these beaches over the 2007 and 2008 conditions. The Coastal Research Center will continue to monitor the conditions on the Cape May Point beaches following the recent ACOE project changes to the shoreline at the Borough s request. Sincerely, Dr. Stewart Farrell Director Coastal Research Center 8