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Clam Bay Maint. Dredging & Sand Minutes 03/09/2009 March 9, 2009 MINUTES OF THE MEETING OF THE COLLIER COUNTY CLAM BA Y MAINTENANCE DREDGING AND SAND BYPASSING SUBCOMMITTEE Naples, Florida, March 9,2009 LET IT BE REMEMBERD that the Clam Bay Maintenance Dredging and Sand Bypassing Subcommittee, in and for the County of Collier, having conducted business herein, met on this date at 9:00 AM in REGULAR SESSION in the Conference Room of Coastal Zone Management, 3300 Santa Barbara Boulevard, Naples, Florida, with the following members present: CHAIRMAN: David Roellig Kathy Worley David Farmer ALSO PRESENT: Gary McAlpin, Director, Coastal Zone Management Gail Hambright, Accountant MEETING AGENDA CLAM BAY MAINTENANCE DREDGING AND SAND BYPASSING SUBCOMMITTEE MEETING MONDAY, MARCH 9, 2009 - 9:00 A.M. COASTAL ZONE MANAGEMENT (3300 Santa Barbara Blvd., Naples) I. Call to Order II. Pledge of Allegiance III. Roll Call IV. Appointment of Subcommittee Chairman and Chairman Comments V. Public Comments VI. Staff Reports VII. New Business 1. Sand Bypassing History and Regulations a. 2008 Aerial of Clam Pass and Surrounding Beaches b. Florida Statutes and Regulations c. Clam Pas Beach Park Renourishment needs d. Work/Views by CP&E and Humiston & Moore e. Technical Evaluation by neutral consultant - PBS&J f. Progress to Date 2. Next Steps VIII. Old Business IX. Public Comments X. Announcements XI. Committee Member Discussion XII. Next Meeting Date/Location TBD XIII. Adjournment All interested partied are invited to attend, and to register to speak and to submit their objections, if any, in writing, to the board prior to the meeting if applicable. For more information, please contact Gail D. Hambright at (239) 252-2966. March 9, 2009 I. Call to Order Gary McAlpin, Director of Coastal Zone Management, called the meeting to order at 9:06 AM. II. The Pledge of Allegiance was recited. III. Roll Call A quorum was established. IV. Appointment of Subcommittee Chairman and Chairman Comments Kathy Worley nominated David Roellig to serve as Chairman. Second by David Farmer. Carried unanimously, 3-0. Chairman Roellig stated Clam Bay is an integrated system and it will be difficult to take out pieces to examine separately. The entire system, including flushing, water quality and mangroves, should be viewed together. V. Approval of Agenda Kathy Worley moved to approve the Agenda. Second by David Farmer. Carried unanimously, 3-0. VI. Public Comments (None) VII. Staff Reports (None) VIII. New Business 1. Sand Bypassing History and Regulations a. 2008 Aerial Map of Clam Pass and Surrounding Beaches Gary McAlpin distributed copies of the aerial map consisting of two pages. The second page focused on Clam Pass. Mr. McAlpin introduced David Farmer who is the newest member of the 9- member Clam Bay Advisory Committee and has a civil engineering background. David Farmer stated he is a licensed Civil Engineer, a licensed General Contractor, and a Certified Professional Land Planner. His course of study focused on hydraulics: "closed conduit" (the study of flow through pipes), and "open-channel flow" which is the subject of the Subcommittee's study. Mr. McAlpin explained the Subcommittee was tasked to determine if it will be possible to dredge a larger area, instead of the normal 80 foot-wide cut, by examining the ebb shoal, and how much additional sand can be pulled from the area, if needed. Staffs goal is to collect technical data for analysis. He stated 2 March 9, 2009 the sand from the proposed expanded dredging area would be used to renourish Clam Pass Beach Park. . There is a continual drift of sand, approximately 10-20,000 cubic yards, from North to South. · Clam Pass interrupts the normal flow of material and deposits sand on the outlet, called the ebb-tide shoal ("sand bar"), which results in starving the down-drift beaches. . The Florida Department of Environmental Protection encourages depositing dredged beach-quality sand at the down-drift beaches. · Collier County wishes to have the capability to move sand if necessary · The sand at the Pelican Bay Beach will erode if not renourished · The analysis will help determine what is "the right thing to do" from a technical standpoint. · In September, 2006, the Coastal Advisory Committee commissioned a study which was conducted by Coastal Planning & Engineering to determine how much sand could be safely removed. · A study was also conducted by Humiston & Moore, commissioned by Turrell, Hall & Associates on behalf ofthe Pelican Bay Foundation. The results of the H&M study conflicted with the results of the CP&E study. Each party claimed the other was biased. · The CAC commissioned PBS&J to conduct an independent review of the previous studies and perform a coastal engineering study to provide technical data. . In 1989, the mangroves began to die, and the first dredging event occurred. While dredging made Clam Bay more hydraulically efficient, an ebb-tide shoal was created in the process of cleaning out the channel, as an unintended consequence of the tidal flushing. · Since 1989, yearly monitoring data has been provided to the Florida Department of Environmental Protection measuring beach width and sand volume which fluctuates from year to year. · The goal is to determine the correct amount of dredging that will not create a detriment to the down-drift beaches. Chairman Roellig questioned the need for another study in view of the previously conducted studies. Mr. McAlpin stated significant improvements in modeling and data acquisition have been made over the past ten years. PBS&J has been hired to review all of the raw data previously acquired and to determine if new modeling is necessary to make specific recommendations as commissioned by the Coastal Advisory Committee. Chairman Roellig stated the optimum result is to keep the Pass self-flushing without the need for dredging. Kathy Worley noted the dredging cycle was reduced from 4 to 5 years to 3 years due to the use of smaller cuts which appeared to be more hydraulically efficient. 3 March 9, 2009 Mr. McAlpin stated there was no basis for the existing 3-year cycle and one of the goals of the PBS&J report will be to recommend an optimum dredging cycle. David Farmer questioned the depth of the cut. b. Florida Statutes and Regulations CDES ("Community Development and Environmental Services") obtained a Letter of Consistency from the State of Florida and Collier County is in compliance with Florida Statutes and Regulations. Mr. McAlpin stated CDES has retained its institutional knowledge. c. Clam Pass Beach Park Renourishment needs Determine how much dredging is necessary to keep the mouth of the Pass open, and encourage flushing to maintain the health of the mangroves and the estuary. d. Work/Views by CP&E and Humiston & Moore Mr. McAlpin stated the previous studies were conducted from different perspectives, i.e., the focus was different for each. The PBS&J study will present a balanced approach. e. Technical Evaluation by neutral consultant - PBS&J, Jeff Tabor Jeff Tabor, PBS&J, gave a PowerPoint presentation and stated: . The depth ofthe cuts has remained at -5.5 feet . The Pass has closed periodically throughout history · Previous studies and data accumulated from 1998 through 2005 will be evaluated with regard to accuracy of the data and the changing trends in the shoreline and wave volume · Also considered will be the dredging depth, the dredging area, the creation of a sediment sink, the undesirable impact to adjacent shorelines, and whether or not to allow natural by-passing to continue . Elements will include wave focusinglenergy/transformation/tidal- driven velocity . Modeling will consider the present condition of Clam Bay and calibrate the wave size and currents; develop alternative for ebb cutting, whether or not to maximum sand mining and the potential impact . Goal: to update findings from 2005 to present, measure transportation rates and develop a sediment budget · The comparative study will take approximately 6 months to complete Mr. McAlpin stated the study is funded by Tourist Tax Dollars and from the County's General Fund. The CAC selected PBS&J as a neutral party because it did not have previous ties to the County or a vested interest in the outcome. Kathy Worley stated studies have been done for Doctor's Pass, Wiggins Pass, etc. as individual units without viewing the "big picture," i.e., the shoreline as a whole. She also stated the effect of what was done in a particular Pass to the 4 March 9, 2009 remaining Passes did not appear to be considered as the entire coastline must be taken into consideration as an entity. f. Progress to Date PBS&J was asked to curtail any activity until formation ofthe Subcommittee. The next steps: . Develop Scope of Work · Move forward with the modeling developed by PBS&J to calibrate the exterior of Clam Bay, predict morphology (a changing of the outside ground structure) and evaluate the continuity between flushing and water quality · PBS&J will review the wave information obtained from the Wiggins Pass model and data obtained from the Coast Guard · Update the Subcommittee periodically regarding the modeling process and calibration . Present recommendations to achieve an optimum ebb-shoal dredging cycle while preventing erosion to Pelican Bay PBS&J will present its findings and recommendations to the Subcommittee who will report to the full Committee and develop a Master Plan for the Estuary. Kathy Worley stated she wanted to hear the opinions of the other Consultants and suggested they also make presentations to the Subcommittee. David Farmer stressed the need for professional opinions from Engineering firms (not Contractors). He requested PBS&J also present a sensitivity analysis. Gary McAlpin stated he will schedule presentations by the other Consultants and will request for peer review and analysis from University of Florida and Duke University but requested to not delay moving forward with PBS&J's data collection and model development. He suggested a parallel track. X. Public Comments Linda Roth stated the goal should be to ensure the health of the Clam Bay Estuary by utilizing minimal dredging as recommended in the 10-year Clam Bay Management Plan. The ultimate goal is to open up the Estuary to allow for natural flushing to maintain its health. She expressed concern regarding potential damage to the present eco-system simply to benefit the beaches. The dredging at Wiggins Pass made the situation worse. Mr. McAlpin stated Wiggins Pass has been dredged for strictly navigational reasons which are not applicable at Clam Bay. Marcia Craven, Pelican Bay Resident, Mangrove Action Committee, Friends of Clam Bay, stated the current permit references the "Clam Pass Natural Resource Protection Area." The permit application for Pass maintenance does not reference 5 March 9, 2009 tidal wetlands or any viable wetlands system. The Coastal Zone Management Plan of 1991 stated "Clam Pass utilizes a natural process of sand bypassing." She asked ifit was necessary to spend more money to jeopardize the stability ofthe area. Mr. McAlpin stated it is the responsibility of the Clam Bay Advisory Committee to integrate the information provided by its four Subcommittees to obtain an overall picture of the area and to reflect the recommendations of the Subcommittees in the Master Plan. Gary Farmer moved to commence the PBS&J Study as previously discussed including sensitivity analysis, data collection and modeling program. Second by Chairman Roellig. Kathy Worley requested the motion include presentations by previous Engineers and Consultants. Gary Farmer amended his motion: to commence the PBS&J Study, as previously discussed, including sensitivity analysis, data collection and modeling program and, to the best of the County's ability, to bring back the actual Consultants - not just a representative of the firm - to answer questions concerning the results of the previous studies. Second by Chairman Roellig. Mr. McAlpin suggested allowing two months in order for Mr. Tabor to develop the model. He stated he will notify the Subcommittee when significant process has been obtained to schedule another meeting. Motion carried unanimously, 3-0. IX. Old Business (None) XI. Announcements (None) XII. Committee Member Discussion (See above) XIII. Next Meeting Date/Location (To be determined) There being no further business for the good of the County, the meeting was adjourned by order of the Chair at 11:10 AM. 6 March 9, 2009 Clam Bay Maintenance Dredging and Sand Bypassing Subcommittee David Rollig, Chairman The Minutes were approved by the Board/Committee Chair on as presented or as amended 7