Broad Beach Sand & Dune Habitat Restoration Project Broad Beach Revetment Owners August 29, 2015
Proposed Broad Beach Restoration MISSION: 1.Restore historically wide beach by adding sand and restoring dune habitat 2.Maintain buried permanent revetment for future storm protection.
Alternative 4C Highlights - Project Footprint: No nourishment west of Broad Beach Road -Revetment Alignment: Affects BB Rd -Revised Dune Plan: 3:1 ratio of dunes restored to dunes impacted -Septic Feasibility Study: Complete w/in 3 yrs of CDP -Backpassing & Nourishment Triggers: Avoid lateral access easements -Comprehensive Monitoring Plan & Science Advisory Panel: BBGHAD & CCC to share management -Requested 20 year term: 10 yr + extension?
Project Update Post 12/14: Extensive meetings with senior regulatory staff members Progress: overall Project concept, west end nourishment, revetment location and entitlement; sand source, spec, and logistics Alternative 4C: submitted 4/15 CCC hearing: anticipated 10/15 Army Corps & others: approx Fall 2015 Proposed Construction Start: Early 2016?
Beach Restoration: Photo Simulation- West
Beach Restoration: Photo Simulation- Central
Beach Restoration: Photo Simulation- Central from 31048
Beach Restoration: Photo Simulation- East
Typical Proposed Beach & Dune Cross Sections Broad Beach Road Broad Beach Road
Revetment Realignment – to Pullback contemplated since 2010 ECDP BBGHAD contested & negotiated pullback mandated by CCC/ other agencies Realignment may alter certain backyard improvements
Revetment Realignment- updated 8/28/15
Post Construction Condition Eastern End of Revetment Pulled Back Revetment Covered with Dune Plants Nourished Beach Final dune design subject to approved dune restoration plan
Existing Condition Existing 2010 Revetment As shown: Broad Beach Rd.
BBGHAD Proposed Revetment Pullback Nourished Beach Condition Pulled Back Revetment Covered with Dune Plants Nourished Beach Existing Leach Fields Future Leach Field Final dune design subject to approved dune restoration plan As shown: Broad Beach Rd.
BBGHAD Proposed Revetment Pullback Nourished Beach Condition Pulled Back Revetment Covered with Dune Plants Nourished Beach Existing Leach Fields Future Leach Fields Final dune design subject to approved dune restoration plan As shown: Broad Beach Rd.
BBGHAD Proposed Revetment Pullback Nourished Beach Condition Pulled Back Revetment Covered with Dune Plants Nourished Beach Existing Leach Fields Future Leach Fields Final dune design subject to approved dune restoration plan As shown: Broad Beach Rd.
BBGHAD Proposed Revetment Pullback Nourished Beach Condition Pulled Back Revetment Covered with Dune Plants Nourished Beach Existing Leach Fields Future Leach Fields As shown: Broad Beach Rd. Final dune design subject to approved dune restoration plan
Alternative 4C: Proposed Dune Footprint: West to Middle Area
Alternative 4C: Proposed Dune Footprint: Middle to East End
West End Nourishment Limitation Ends nourishment at Broad Beach Rd. Preserves “boulder field” between and Limits depth of cover to approximately natural conditions west of Boulder Field 31380
West End Sensitive Marine Resources Broad Beach Rd 21
Summary of West End Analyses GOAL 1: Natural sedimentation levels determined - Spring accumulation varies up to 3 feet - Fall accumulation up to 5 feet GOAL 2: Project-related sand transport & burial determined - 3D mapping used to quantify Project burial exceeding natural levels GOAL 3: Impacts to sensitive resources analyzed - No predicted impact to eelgrass and kelp - Impacts to surfgrass predicted to be less than significant - Impacts to lower intertidal boulder field predicted to be less than significant - As expected, beach nourishment project adds sand to upper intertidal and sandy habitats
Septic System Study Proposed Compromise: 2 years after CDP becomes effective Implementation based on findings: 6+ yrs
Proposed Backpassing & Renourishment Triggers ActivityTriggered when… BackpassingWest end beach less than 75’ for 3 months and sufficient sand at east end to backpass: likely 1-2x per 5 years Interim Nourishment West end beach less than 30’ for 6 months Add up to 75,000 cy: proposed assessment funds no more than 3 per 5 yrs. Avoid summer placement Discretionary Erosion Nourishment Less that 10’ dry beach width fronting revetment Place at least 75,000 cy / avoid summer placement Not discretionary – GHAD commits to keep minimum 10’ beach width fronting revetment instead of providing lateral access easements landward of revetment Maximum 3 erosion nourishments within 10-yr period
BBGHAD’s Proposed Monitoring Resource Monitoring During Construction Adaptive Management and Monitoring Dune Habitat Restoration and Monitoring Plan Long-term Marine Resources Monitoring, Reporting, and Mitigation Plan Public Access Management Program Science Advisory Panel ("SAP“) Cost: Approximately $3M/10 years
Beach Width Monitoring “Transects”
Primary Remaining Issues With CCC 1.Revetment Alignment & Duration 2.Dune footprint 3.Scope of public/lateral access 4.Permit term 5.SAP Details 6.Sand specification
Moving Forward 1.Revised Engineer’s Report- Board adopted July 2015; Resolution No. 2015/03 2.Proposed New Assessment: $595/linear foot; 25% for those west of Property Owners’ vote on new assessment: ends 9/6/15 at 9:00 a.m. 4.Construction Schedule: Early 2016?
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Predicted Westward Sand Transport After 75,000 cy “Interim Nourishment”