Beach Restoration in Okaloosa and Walton Counties. FSBPA Technology Conference Clearwater, FL

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1 Beach Restoration in Okaloosa and Walton Counties FSBPA Technology Conference Clearwater, FL Presented by: Duncan Greer, E.I. February 5, 2015

2 PRESENTATION OUTLINE 1. Overview of Project Locations 2. Eglin Air Force Base (AFB) Beach Restoration 3. Western Destin Beach Restoration 4. Destin/Walton County Beach Restoration 5. Qualitative Design Comparisons 2

3 Overview of Project Locations 3

4 Overview of Project Locations 4

5 Eglin AFB Beach Restoration Project 5

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10 Eglin AFB Beach Restoration Project Mission Control Structures Project Construction: April June 2010 Reach 1 Approximately 3,500 feet constructed ~265,000 cy (75.7 cy/ft) V-511 to V (Okaloosa County) Reach 3 Approximately 7,000 feet long ~730,000 cy (104.3 cy/ft) V to V (Okaloosa County) Funding limitations amidst Oil Spill Reach 1-9,500 feet not constructed Reach 2 not constructed Permit Expired: March

11 Eglin AFB Beach Restoration Project 3 rd Year Monitoring Report: September 2013 Project Areas (Pre-construction vs. 3-year condition) Average MHW +47 ft in Reach 1 and +88 ft in Reach 3 Net 81,300 cy in Reach 1 and 525,500 cy in Reach 2 Control Areas (Pre-construction vs. 3-year condition) Reach 1 West +17,500cy (+28.6 ft), East -71,700 cy (+12.0 ft) Reach 3 West +185,700cy (+20.5 ft), East +23,100 cy (+6.3 ft) Summary ~72% (Reach 3) and ~31% (Reach 1) of placed volume Reach 1 underperformed, 24% constructed, tropical activity in 2012 Reach 3 exceeded performance expectations, USACE 2010 placements 11

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13 Western Destin Beach Restoration Project 13

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16 Western Destin Beach Restoration Project Project Construction: January 29 February 25, 2013 Reach 1 Approximately 4,100 ft - ~487,000 cy (118.8 cy/ft) East Jetty to R-20.7 Gap Area Approximately 2,900 ft 18 single family lots / 3 condominium properties Reach 2 Approximately 2,250 ft ~147,000 cy (65.3 cy/ft) R-23.5 to R

17 Western Destin Beach Restoration Project 1 st Year Monitoring Report: October 2014 Project Areas (Pre-construction vs. 1-year condition) Average MHW +123 ft in Reach 1 and +65 ft in Reach ,100 cy in Reach 1 and +100,900 cy in Reach 2 Control Areas (Pre-construction vs. 1-year condition) Gap Area +112,900 cy (MHW +68 ft) East Control Area +13,400 cy (MHW +40 ft) Summary Project contains ~ 80% of initial volume Compared to 1-year predictions, 16-month results Reach 1 (+19%), Reach 2 (+23%) Post-Con to 1-Yr comparisons: Gap accreted 57,600 cy 17

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20 Destin/Walton County Beach Restoration Project 20

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23 Destin / Walton County Beach Nourishment Project Sequential Erosion Approximately 7 miles of beach - 2.8M cy (75 cy/ft) R-39 (Okaloosa County) to R (Walton County) Project Construction February May 2006 (R-6 to R23.8 Walton County) December January 2007 (R-1 to R-6 Walton County) May June 2007 (R-39 to R-50 Okaloosa County) 23

24 Destin/Walton Beach Nourishment Project 7 th Year Final Monitoring Report: October 2014 Beach and Offshore Areas (Pre-construction vs. 7-year condition) Average MHW +114 ft Average MHW +62 ft within control areas Net accretion of 2,177,800 cy in project area Borrow Area Continues to accumulate material (gained 613,060 cy since construction) No adverse effects on neighboring shoreline Summary Project contains ~78% of initial volume compared to pay surveys Project contains 94% - 99% of initial volume compared to 2007 Post-Const. Apparent equilibrium 24

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26 Destin/ Walton Project Monitoring Summary Successfully Met The Design Goals Storm induced erosion mitigated Pre-Opal conditions Increased storm protection to upland properties and structures Increased berm widths and offshore bar formations Withstood numerous storm events (TS Barry, Erin, Eduardo, Fay, Claudette, Lee, Debby, Beryl, Andrea and Hurricanes Gustav, Ike, Ida, Isaac) Aesthetically pleasing and provides increased recreational benefits Provides enhanced marine turtle and nesting shorebird habitat 26

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29 Design Comparison Variables Typical beach nourishment design principles Project length, fill density, overfill ratios, background erosion rates, etc. Project timelines / timescales Eroded condition of the pre-construction project area Initial profile condition can significantly affect equilibration Naturally occurring phenomena Offshore / nearshore bar migration or welding Beach cusps (prevalent in this area of Florida) Dominant coastal features (historic rip channels, erosion hotspots, etc) Storm impacts and seasonal variability 29

30 Fill Template Comparison 30

31 Qualitative Comparison of Design and Evolution Eglin Air Force Base 31

32 Qualitative Comparison of Design and Evolution Eglin Air Force Base 32

33 Qualitative Comparison of Design and Evolution Western Destin 33

34 Qualitative Comparison of Design and Evolution Western Destin Gap Area 34

35 Qualitative Comparison of Design and Evolution Walton/Destin 35

36 Qualitative Comparison of Design and Evolution Walton/Destin 36

37 Discussion of Qualitative Design Comparisons Eglin AFB Maintained back berm increased dune protection Generally maintained berm elevation Western Destin Still equilibrating Walton/Destin Berm reduced after 1-2 years (Ike and Gustav) Larger transition from dune to berm Good performance overall, design goals achieved One size does not fit all All designs perform as desired 37

38 Thank you! Questions? 38