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Backup Documents 04/19/2010 R WIGGIN'S PASS SUBCOMMITTEE MEETING BACKUP DOCUMENTS APRIL 19, 2010 ____I Agenda Item No. 1601 April 13. 2010 Page 1 of 3 EXECUTIVE SUMMARY Recommendation to approve and appoint the proposed Inlet Management Work Team for Wiggins Pass as recommended by the Coastal Advisory Wiggins Pass Subcommittee. 9BJECTlVE: To approve and appoint the proposed Inlet Management Work Team for Wiggins Pass as recommended by the Coastal Advisory Wiggins Pass Subcommittee. CONSIDERA TlONS: As a condition of the permit application for the maintenance dredging and navigational improvement project, the FDEP is requiring an updated Inlet Management Plan for Wiggins Pass. The CAC is recommending that a Work Team of community stakeholders be approved and appointed by the BCC. This Work Team would be charged with the development of the updated Wiggins Pass Inlet Management Plan for review by the CAC. This Work Team would report to the CAC and be active for one year while the plan was being developed concurrent with the permit application. The CAC is recommending the following appointments: . Joe Moreland - Chairman of this committee and CoWer County representative on the CAG. . Victor Rlos - Marco Island representative on the CAC. . Bob Raymond - Naples representative on the CAe. . Nicole Ryan - Representative of the Conservancy of SW Florida . Dick Lydon - Representative of the Vanderbilt Beach . Jim Fox - Representative of the Boating Community . Tom Crowe - Representative of the Friends of Barefoot Beach . Jeff Raley - Representative of the Florida Park Service (DWSP) . Jack Kindsvater - Representative of the ECA These meetings will be publically noticed and held in compliance with Florida's Sunshine Law. It is expected that this rework of this Inlet Management Plan may cost in excess of $250.000 to accomplish. Staff has applied for FDEP cost share funding for this contract. Once a scope of work is developed, a cost estimate will be developed for funding. ADVISORY COMMITTEE RECOMMENDATIONS: On March 8, 2010 the Coastal Advisory Wiggins Pass Subcommittee recommended approval of this item (3-0). On March 11.2010 the CAC recommended approval of this item (9-0). FISCAL IMPACT: The Source of funds is from Category UN Tourist Development Tax fund 195. Agenda Item No. 1601 April 13, 2010 Page 2 of 3 GROWTH MANAGEMENT IMPACT: The revised Inlet Management Plan will conform to all growth management and land development code requirements. LEGAL CONSIDERATIONS: This item has been reviewed and approved by the County Attorney's Office and is legally sufficient for Board action. -CMG RECOMMENDATION: Recommendation to approve and appoint the proposed Inlet Management Work Team for Wiggins Pass as recommended by the Coastal Advisory Wiggins Pass Subcommittee. PREPARED BY: J. Gary McAlpin, P.E., CZM Director Agenda Item No. 16D1 ApriI1:!.2010 Page 3 of 3 COLLIER COUNTY BOARD OF COUNTY COMMISSIONERS Meettng Date: 1601 Recommendation to approve and appOint the proposed inlet Management Work Team for INiggins Pass as recommended by the Coastal Advisol)' INigglns Pass Subcommittee, 4/13/2010900:00 AM Item Number: Item Summary: Appro\'ed By Kathy Carpenter Public Services Executive Secretary Date Public Services Admin. 3112/20102:27 PM Approved By Gary McAlpin Director. Co_tal Management Programs Dat& Public Services Division Coastal Zone Management 3112/20102:46 PM Approved By Colleen Greene A.sslstant County Attorney Oate County Attorney County Attomey 3115120104;58 PM Approved By Jeff Klattkow County Attorney Date 3116120101:27 PM Approved By Marla Ramsey Administrator. Public Services Date Public Services Oivlsion Public S.rvlces Division 31251201011:23 AM Approved By OMS Coordinator Date County Manager's Office Office of Management l Sudget 312512010 3:06 PM Approved By Leo E. Ochs, Jr. County Manager Date County Mlnage/ll Offic& County Managers OffiCI! 415120104;00 PM \lVtggins Pass Sub Apfil19, 2010 VUI.1 New Business 1 of 5 Summary of 2000 Inlet Management Plan Requirements I. "Continue to bypass sediment to the downdrift beaches." ""As a minimum ... average annual placement... of 82.000 cubic yards to the west." ., "Implement strategies for managing Norriego Point" "Stabilization of Norriego Point will allow [more] material dredged from the inlet...to be placed on downdrift beaches:' 3. Implement a comprehensive beach, inlet. and offshore monitoring program .....to identify beach placement locations for future bypassing efforts and to revalidate the sediment budget:' 2009 East Pass Study Findings I. The Corps 0 f Engineers has successfully 111 aintained the East Pass navigation channel by dredging a pproximately 100.000 cubic yards of material annually between 1999 and 2008. ., East Pass h as si gnificantly influenced t he coastline f or a distance 0 f approximately 9.000 ft. east and west of the inlet during the 1996 to 2007 study period. 3. Over long periods of time. sediment transport along the coastline adjacent to East Pass i s predominantly from east to west. This i s supported by the s emvard position of the shoreline to the east of th e jetties relative to the western shoreline position. 4. East of the pa ss. "reversed" sediment transport fro m ,...est to east has occurred from 1996-2007. The Holiday Isle area (R 17 to R26) now features the highest erosion rates in Okaloosa County and has been designated as "Critically Eroded", 5. West of the pass. the sediment transport is from east to west. 6. Inlet management procedures should be modified to be able to accommodate both east and west sediment transport scenarios and variable quantities. V'Aggins Pass Sub Aprt119, 2010 VlII.1 New Business 2 of 5 7. The \}.'alton Co. Destin Beach Project ebb shoal bon-ow area does appear to have caused some limited erosional impact to the adjacent shorelines. 8. An ebb shoal swash channel near the east jetty may be partially responsible for the high beach erosion rate east of the inlet. 9. The potential impacts of the proposed Western Destin Borrow Area are predicted to be minor. 10. Dredge spoil material placed in the beach disposal area west of the inlet will take several years to reach Fort Walton Beach under typical wave climates. Preliminary Inlet Management Modification Recommendations (subject to discussion and modification at the yd T AC meeting) I. 'rhe present inlet management plan provides for sand transfer only in the western direction. T he pi an should be m oditied tor espond to variations in sediment transport both in east and "vest directions. The volume o I' material will vary' for each maintenance dredging event. ., Prior to future channel dredging operations. analyze beach profile survey results to de termine t he apparent sediment transport direction (i.e. sediment budget update or odd! even analysis) and volumes. 3. To accomplish this. conduct annual, concurrent. be ach p ronIe surveys 0 n bot h sidesofthcinlct from protilesV-601 toR-33. starting in 2010. In addition to profiles V -611 to V-62 I. which are presently be ing surveyed. this w ill require new surveys of profiles V-60 I to V-61 0 (west of the pass) and R 17 to R33 (east of the pass) to be initiated. 4. Place t he inlet ch annel dredge spoil material t he on t he dow ndrift beaches strategically to address recent erosion trends and erosion hot spots. 5. The City should continue with the ongoing design and permitting efrort to armor Non-iego Point Construction ofth e stabilization project will eliminate th e placement of approximately 29,000 cubic yards of channel maintenance dredging material at this location and allow for tht~ material to be placed on the beaches. Wiggins Pass Sub April 19, 2010 VlII.1 New Business 3 of 5 Wiggins Pass Policy and Planning Guidelines Discussion Points Current FDEP State Strategic Management Plan for Wiggins Pass Strategy: Place beach quality maintenance dredged material on adjacent beaches north and south of Wiggins Pass within areas of greatest need; monitoring and analysis of inlet effects. One of the Pertinent State Rules: Pursuant to 62B.41.005(15), FAC., the plan shall provide for continued bypassing of the sand in sufficient quantity to insure that net long term erosion or accretion rates on both sides of the inlet remain equal except in cases where unequal erosion and accretion rates excess of an be shown to be a result of natural processes and not caused by human activities. In all cases, mitigation shall be provided for any erosion effects to the adjacent coastal system attributable to alteration of the inlet. The mitigation shall include the placement of supplemental beach compatible material as needed (FOE? RAI #1 March 24, 2010). The actual full enforcement this rule is scarce or not well documented, but could be expensive to implement. New 2010 Start Point for Discussion on new plan New General Policy 1. Bypass sand so that the average annual volumetric erosion rate of the sand is equal north and south of the inlet since a base year of 2001. 2. Implement any mitigation or contingency during major dredging events. Major Findings 1. Flood channel migration eroding Barefoot Beach 2. Sand bypassing to the north was insufficient 3. Alongshore Transport is northward 4. Inlet is filling significantly from the south in addition north 5. RQ(;k substrate on both side of channel 6. Impact to Delnor Wiggins Park has been general positive since dredging began Initial Inlet Management Plan recommendation -Feb 2010 1. Straight alignment through the flood and ebb shoals. 2. Minor cuts to subsurface rock ledge - no impact on positional stability 3. Maintain navigation for 3 foot draft vessel & extend dredging interval (no structures) VVlggins Pass Sub Apli119, 2010 Vtll-1 New Business 4015 4. Mitigate for inlet impacts by bypassing 2.65 times to North 5. Establish monitoring program and adjust disposal practices in 4 above accordingly 6. Repair beach scarps and the south point of Barefoot Beach Park. .S<>~ ~ 7. Use sand dredged from the flood shoal to create new flood shoal flats 8. Allow moderate design channel migration (ebb channel =&- 50" and flood 50 feet to north) to reduce dredging. 9. Use intermediate (small) dredging to reestablish navigation thru the bar 10. Summer maintenance dredging to reduce cost and complexity, with offshore placement. 1995 Inlet Management Plan Recommendation The plan presented in this section is the best combination of alternatives able to achieve a cost effective inlet management plan. The recommended plan mitigates for the impact of Wiggins Pass on adjacent shorelines and improves the navigability of the inlet. The major components of the plan include: 1. Widen and deepen the existing navigation channel to a dredged depth and width of 250 feet and -12 feet MLW, respectively. Straighten and shift the channel's boundaries. The existing subsurface rock ledge, if encountered, shall be left in place. 2. Maintain a minimum operating depth in the channel of -8 feet MLW (-9 feet NGVD) with a maintenance dredging program scheduled at two-year intervals. 3. Establish beach disposal sites outside the zone of inlet influence. Mitigate for inlet impacts by bypassing to the south a minimum of 6,500 c.y.lyr. 4. Establish navigable depths for three-foot draft boats in the interior channels of Wiggins Pass. Implement improvements as needed. 5. Establish a program of beach, inlet shoal, interior channel and environmental monltoring_ 6. Adopt a three-foot draft boat as the planning and design standard for the Wiggins Pass basin. w ~ ~ z ~. ~ . >>>n i 5~~Bmhn i!" t:;;;b~~O~i"lQ zi~88~~H ~nic:zO...(g~ n::;~I~82~ j;~2~C;\ll~!I:", ci~;l\o"!~l! hiil~~g~;ill C)zt!h...a!t"'t;;.... 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