STATE OF THE COAST 2016 Coastal Frontiers Corporation June 1, 2017

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1 STATE OF THE COAST 2016 Coastal Frontiers Corporation June 1, 2017 Shoreline Preservation Committee

2 1. Background OVERVIEW 2. Monitoring Program 3. Results El Niño Post-RBSP II Post-RBSP I 4. Conclusions

3 STUDY AREA Oceanside Carlsbad Oceanside Cell Encinitas Solana Beach Del Mar Mission Beach Cell La Jolla Mission Beach Silver Strand Cell Imperial Beach

4 Cumulative Nourishment Volume (cy) NOURISHMENT HISTORY ( ) 6,000,000 5,000,000 Oceanside Cell 4,000,000 3,000,000 RBSP I RBSP II 2,000,000 1,000,000 Silver Strand Cell Mission Beach Cell Monitoring Year

5 MONITORING PROGRAM History Established in 1996 Adaptive and Sustainable Objectives Measure Changes in Shorezone Monitor RBSP Beach Fills Components Beaches Lagoon Entrances Offshore Borrow Sites

6 Beach Monitoring Semi-Annual Profile Surveys 60 Shore-Perpendicular Transects Fall and Spring Surveys Backbeach to Beyond Depth of Closure

7 RESULTS Analysis Periods El El Niño Post-RBSP II ( ) Post-RBSP I ( ) Regions Littoral Cells Sub-Reaches Beach Parameters Beach Width Shorezone Volume

8 El Niño Wave Climate Summary Pre-El Niño Beach Condition Beach Changes

9 Wave Energy Index El Niño: Wave Energy Monitoring Year

10 Reach Pre-El Niño Beach Widths Ave. Beach Width (ft) Fall 1997 Fall 2015 Ave. Beach Width Change (ft) Oceanside North Carlsbad South Carlsbad Leucadia/Encinitas Cardiff Solana Beach Del Mar La Jolla Mission Beach Imperial Beach

11 Winter Seasonal Beach Width Changes Reach Max Ave (ft) (ft) (ft) Severity Oceanside of 19 North Carlsbad of 19 South Carlsbad of 19 Leucadia/Encinitas of 14 * Cardiff of 12 * Solana Beach of 19 Del Mar of 19 La Jolla of 19 Mission Beach of 19 Imperial Beach of 19 * El Niño season not included

12 Reach Summer Recovery Winter Loss (ft) Summer Recovery (ft) % Recovery Oceanside % North Carlsbad South Carlsbad % Leucadia/Encinitas % Cardiff % Solana Beach % Del Mar % La Jolla % Mission Beach % Imperial Beach %

13 2016 Summary Region Wide Winter Beach Width Losses Incomplete Summer Beach Width Recovery Modest Shorezone Volume Losses

14 Post-RBSP II Beach Changes Receiver Sites Initial post-nourishment gains Subsequent placement site losses and downcoast gains Regional Gains in Silver Strand Cell Back to pre-nourishment condition on Oceanside Cell Sub-Reaches Sustained (4+ yrs) shoreline advance in 5 of 9 reaches Sustained (4+ yrs) volume gains in 5 of 9 reaches

15 Reach Beach Width Persistence Long-Term Beach Width Gains (5 years) Fall 2016 Beach Width Change Imperial Beach 5 years 60 ft North Carlsbad 5 years 27 ft Transient Beach Width Gains (2 to 4 years) Solana Beach 4 years 39 ft Cardiff 4 years 6 ft Oceanside 4 years -9 ft La Jolla 3 years -1 ft Negligible Beach Width Gains (1 year or less) South Carlsbad 1 year -5 ft Del Mar < 1 year -16 ft Leucadia/Encinitas < 1 year -15 ft

16 Reach Shorezone Vol. Persistence Fall 2016 SZ Vol. Change Long-Term Shorezone Volume Gains (5 years) Imperial Beach 5 years 45 cy/ft La Jolla 5 years 12 cy/ft North Carlsbad 5 years 24 cy/ft Transient Shorezone Volume Gains (2 to 4 years) Solana Beach 4 years 29 cy/ft Cardiff 4 years -15 cy/ft Del Mar 3 years 19 cy/ft Negligible Shorezone Volume Gains (1 year or less) Oceanside 1 year -28 cy/ft Leucadia/Encinitas < 1 year -16 cy/ft South Carlsbad < 1 year -12 cy/ft

17 Long-Term Beach Changes (Post-RBSP I) Nourishment ( ) Oceanside Cell: 3 mm cy Mission Beach Cell: 601k cy Silver Strand Cell: 949k cy Shoreline and Shorezone Vol. Changes Oceanside Cell: Shoreline Losses / Vol. Gains Mission Beach Cell: Shoreline Losses / Vol. Gains Silver Strand Cell: Shoreline and Volume Losses

18 CONCLUSIONS 1. El Niño Less energetic than Beaches better prepared in than Severe erosion compared to past winter seasons Incomplete Summer Recovery

19 CONCLUSIONS 2. Beach Condition Post-RBSP II Initial gains at receiver sites followed by Year 1 losses Benefits to Downcoast Beaches Gains in SSLC; Back to pre-nourishment condition in OSLC 4+ years sustained gains in 5 of 9 sub-reaches Long-term (Post-RBSP I) OSLC - Beach width loss; volume gains MBLC - Beach width loss; volume gains SSLC - Beach width at pre-rbsp I levels; volumes loss

20 CONCLUSIONS 3. Nourishment RBSP I and II Contributed to improved Pre-El Niño Beach Condition relative to 1997 Nourishment Deficit in Silver Strand and Oceanside Cells SSLC: -14,000 cy/yr OSLC: -208,000 cy/yr

21 Average Shorezone Volume Change (cy/ft) Average MSL Shoreline Change (ft) Oceanside Cell Changes: Fall 2000 to Fall

22 Average Shorezone Volume Change (cy/ft) Average MSL Shoreline Change (ft) Mission Beach Cell Changes: Fall 2000 to Fall

23 Average Shorezone Volume Change (cy/ft) Average MSL Shoreline Change (ft) Silver Strand Cell Changes: Fall 2000 to Fall