Collier County Summary & Conclusions

• A review of the volume change summary for the Vanderbilt Beach System indicates this project reach is performing exceptionally well.  Net volumetric gains of approximately 19,000 cubic yards have been measured from post-construction through four and one-half years of monitoring.  This system has benefited from reduction of potential sediment transport rates caused by realignment of the shoreline complimented by sediment bypassing from routine Wiggins Pass dredge and fill activities (approximately 83,010 cubic yards from November 1995 to March 2000).
• The Park Shore System has been identified as a "hot spot".  Although the majority of the fill has been retained in the system, the dry beach locally along approximately 3,500 feet of shoreline has experienced excessive erosion as indicated by the measured shoreline recession rates.   On a positive note, the adjacent beaches have experienced shoreline advance and volumetric gains, and the system as a whole has experienced net volumetric gains of approximately 12,000 cubic yards.  The routine bypassing of sand from Clam Pass (approximately 46,000 cubic yards from April 1997 to April 1999) has benefited the updrift beach and the Doctor's Pass Jetty Extension has stabilized the bar system, added tens of feet of beach width, and perched an approximate 28,000 cubic yard wedge of sand transported alongshore from the beach fill onto the downdrift beach.
• The Naples Beach System has experienced net volumetric gains of approximately 30,000 cubic yards.  The fill area experienced modest losses of approximately 14,500 cubic yards.   The downdrift beach has experienced predictable gains of approximately 44,000 cubic yards, resulting mainly from the alongshore transport of the fill from north to south.  The system has benefited from the Doctor's Pass dredge and fill activities (approximately 75,840 cubic yards in September 1996) and the upland sand fills in 1999-2000.

• Coastal Engineering Consultants, Inc. reported that 1,172,650 cubic yards of sand was placed along the shorelines of Vanderbilt Beach, Park Shore Beach, and Naples Beach between November 1995 and May 1996 ( CEC, 1996).   Comparisons of profile data in the project areas between pre-construction (1995) and post-construction (1996) surveys indicate a fill volume of 1,270,600 cubic yards, as measured above -10 feet NGVD.
• Vanderbilt Beach currently maintains a 52.3-ft average beach width (-7.4 ft/yr) and contains 80% of the 1996 construction volume, but lacks elevation on the upper beach.  Park Shore is performing as a 37.0-ft wide beach (-2.7 ft/yr) with 56% of the post-construction fill volume remaining.   The Naples Beach project area is showing a 52.3-ft beach width in 2002 (-4.6 ft/yr) and retains 98% of the volume measured at the completion of the project.  The County's ongoing maintenance of nearby passes and supplemental fill projects have contributed to the performance of the project area beaches.

• The average shoreline changes since last year in the 1996 project areas for Vanderbilt, Park Shore, and Naples Beach are +5.8 feet, -2.9 feet, and +1.1 feet, respectively.
• The total volumes remaining in Vanderbilt, Park Shore, and Naples Beach are 305,000 cubic yards (94%), 61,000 cubic yards (64%), and 812,800 cubic yards (96%), respectively.
• The extension of the north jetty at Doctors Pass has benefitted the beaches on Park Shore.
• The pile cluster region is performing at the level of the overall project area, with increased stability and reduced recession rates within 200 feet of the groin.
• The County's ongoing maintenance of nearby passes and supplemental fill projects has significantly added to the longevity of the project beaches.
• Implied design beach widths of 50, 35, and 50 feet (Vanderbilt, Park Shore, and Naples) suggest that the project areas have performed well overall, but need renourishment to maintain these widths.