Nearshore Rock Exposure at Patrick Air Force Base, Florida

Transcription

1 Kevin R. Bodge, PhD, P.E. Steven Howard, P.E. Will Reilly, P.E. olsen associates, inc. jacksonville, florida Nearshore Rock Exposure at Patrick Air Force Base, Florida

2 Patrick Air Force Base, FL 45 th Space Wing, USAF Cape Canaveral Borrow Areas PICTURE HERE Patrick AFB

3 Patrick Air Force Base N Hydraulic Placement (full template) Stockpile Truck Haul (thin template) Patrick AFB Beach Nourishment (since 2000) 4 Miles of shoreline Two Hydraulic Fill Projects 2001 SPP: 557,300 cy 2005 SPP: 321,500 cy Truck Haul (dune)

4 Patrick AFB Beach Nourishment

5 Patrick Air Force Base N Hydraulic Placement (full template) Truck Haul (thin template) Patrick AFB Beach Nourishment (since 2000) 4 Miles of shoreline Two Hydraulic Fill Projects 2001 SPP: 557,300 cy 2005 SPP: 321,500 cy 2011 Dune Fill: 51,000 cy Truck Haul (dune)

6 Borrow Area (north of inlet)

7 Thin Template / Dune Restoration

8 Title or introduction to the presentation would go here. PICTURE HERE Nearshore Rock Outcrops

9 2 miles south of PAFB Patrick AFB

10 January 2005 Renourishment Monitoring Protocol for Nearshore Rock Annual measurement of the nearshore beach profile elevations Compare profile elevations to the mean pre-project elevations & standard deviation Discern changes in the profile trends Measure occurrence of exposed rock along each profile transect, by wading Discern changes in the rock occurrence Southern 5000-ft of PAFB & 2000-ft downdrift (7 transects) Seven (7) years of annual surveys & reports.

11 400 ft R-monument Profile Transect Exposed Rock (via annual wading transect) Exposed Rock (via 2004 aerial photo) Limits of Exposed Rock (2005, post-hurricanes)

12 Jan 2001 Jun 2004

13 July 2012 MSL

14 July 2012 MSL

15 July 2012 MSL

16 July 2012 Pre-Project Mean Profile and ±1 Std. Deviation MSL

17 Mean Profile through present ( ) Mean Pre-Project Profile ( ) MSL

18 July 2012 MSL 600-ft South of Project Area

19 July 2012 MSL 600-ft South of Project Area

20 July 2012 Pre-Project Mean Profile and ±1 Std. Deviation MSL 600-ft South of Project Area

21 Mean Profile through present ( ) Mean Pre-Project Profile ( ) MSL 600-ft South of Project Area

22 Mean Pre-Project Profile ( ) Mean Profile through present ( )

23 Mean Pre-Project Profile ( ) Mean Profile through present ( )

24 Total Hardbottom Exposure (lineal feet along each transect) R-Mon Jan 01 Jun 04 Feb 05 Jul 06 Jul 07 Jul 08 Jul 09 Jul 10 Aug 11 Jul 12 R R R R R R R R Sum 1,226 1,254 1, ,208 1,608 1, Average pre-project ( ) 1,240 hurricane 1,646 post-project ( present) 1,019 Mean Pre-Project Rock = 1240 feet Mean Post-Project Rock = 1019 feet

25 Total Hardbottom Exposure (lineal feet along each transect) R-Mon Jan 01 Jun 04 Feb 05 Jul 06 Jul 07 Jul 08 Jul 09 Jul 10 Aug 11 Jul 12 R R R R R R R R Sum 1,226 1,254 1, ,208 1,608 1, Average pre-project ( ) 1,240 hurricane 1,646 post-project ( present) 1,019 Post-project rock exposure equaled and exceeded pre-project baseline values

26 Total Hardbottom Exposure (lineal feet along each transect) R-Mon Jan 01 Jun 04 Feb 05 Jul 06 Jul 07 Jul 08 Jul 09 Jul 10 Aug 11 Jul 12 R R R R R R R R Sum 1,226 1,254 1, ,208 1,608 1, Average pre-project ( ) 1,240 hurricane 1,646 post-project ( present) 1,019 Largest rock values were 4-yrs post-project, thence followed by lowest values

27 Initial Fill North Project Area Downdrift Area 200 lineal ft rock exposure Time Abundance of exposed rock by time and location

28 North Initial Fill Project Area Post-Hurr Renourishment Downdrift Area 200 lineal ft rock exposure Time Abundance of exposed rock by time and location

29 Rock Exposure vs. storm wave occurrence in prior 12 months

30 Jul Months Preceeding Rock Survey ROCK EXPOSURE Jul-10 Aug-11 Jul-08 Jun-04 Jul-07Jan-01 Jul-06 Jul-12 Feb month window Percentage of offshore waves greater than 8-ft height for year preceding Rock Survey % OCC. OF STORM WAVES Jul-09 6 Months Preceeding Rock Survey Jul-08 Feb Jun-04 Jul-07 Jan Jul Aug-11 Jul-10 Jul-12 6-month window Percentage of offshore waves greater than 8-ft height for year preceding Rock Survey Rock Exposure vs. storm wave occ. in prior 3-12 months

31 Jul Months Preceeding Rock Survey ROCK EXPOSURE Jul-10 Aug-11 Jul-08 Jun-04 Jul-07Jan-01 Jul-06 Jul-12 Feb month window Percentage of offshore waves greater than 8-ft height for year preceding Rock Survey % OCC. OF STORM WAVES 3-month window Jul-09 6 Months Preceeding Rock Survey Jul-08 Jun-04 Jul-07 Jan-01 Feb-05 Correlation of rock exposure and prior storm wave occurrence did not improve for different wave windows Jul Aug-11 Jul-10 Jul-12 6-month window Percentage of offshore waves greater than 8-ft height for year preceding Rock Survey Rock Exposure vs. storm wave occ. in prior 3-12 months

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33 Conclusions Post-renourishment monitoring ( ) demonstrate an increase in profile elevation along the beach face as intended, with little or variable change across the rock outcrop area. Total rock exposure varied by a factor of 12 during eleven years of monitoring, irrespective of beach fill activity. The greatest rock exposure occurred 3 and 4 years after project renourishment, and the least occurred 6 years after renourishment, with little change in average exposure between pre- and post-renourishment conditions. Fluctuations in rock exposure were consistent with large-scale trends of beach changes observed along the Brevard County shoreline. Some correlation, neither definitive nor predictive, is noted between rock exposure and precedent storm wave occurrence.

34 Kevin R. Bodge, PhD, P.E. Steven Howard, P.E. Will Reilly, P.E. olsen associates, inc. jacksonville, florida Nearshore Rock Exposure at Patrick Air Force Base, Florida