FINAL

BROAD BEACH RESTORATION PROJECT

MARINE HABITAT MONITORING AND MITIGATION PLAN

Prepared for: Broad Beach Geologic Hazard Abatement District 2049 Century Park East, Suite 2700 Los Angeles, CA 90067 Tel: (310) 746-4412 Contact: Mr. Kenneth Ehrlich

Prepared by: Rincon Consultants, Inc. 180 North Ashwood Avenue Ventura, CA 93003 Tel: (805) 644-4455

And

Merkel & Associates, Inc. 5434 Ruffin Road San Diego, CA 92123 Tel: (858) 560-5465

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

TABLE OF CONTENTS

INTRODUCTION ...... 1-1 Background ...... 1-1 Regulatory Agency Monitoring Need ...... 1-1 Approaches to Meeting Monitoring Objectives ...... 1-2 Science Advisory Panel ...... 1-3 Communications Plan ...... 1-3 Centralized Data Management System ...... 1-4 Email Correspondence ...... 1-4 Monitoring Reports ...... 1-5 Semi-Annual Coordination Meetings ...... 1-5 Monitoring Program Authorization Requirements ...... 1-6 EXISTING CONDITIONS ...... 2-1 Broad Beach Project Area of Potential Effect ...... 2-3 Marine Habitats Within the Broad Beach Area of Potential Effect ...... 2-7 Regional and Historic Sampling Programs ...... 2-18 Regional and Historic Data ...... 2-26 REFERENCE SITE SELECTION ...... 3-1 Reference Site Objectives ...... 3-1 Reference Site Evaluation Methods ...... 3-1 Reference Sites Considered ...... 3-2 Reference Sites Selected ...... 3-6 Leo Carrillo ...... 3-9 Sequit Point ...... 3-11 El Pescador ...... 3-12 El Matador ...... 3-13 Reference Site Weakness and Corrective Action Framework ...... 3-15 SAMPLING METHODS, DATA COLLECTION, AND ANALYSIS ...... 4-1 Monitoring Duration and Sampling Periods ...... 4-1 Feature Class Distribution and Areal Extent ...... 4-2 Intertidal and Supratidal Feature Class Mapping ...... 4-2 Subtidal Feature Class Mapping ...... 4-5 Managing Feature Class Mapping Gaps ...... 4-8 Habitat Sampling ...... 4-10 Intertidal Habitat Sampling ...... 4-14 Subtidal Habitat Sampling ...... 4-23 Eelgrass Sampling ...... 4-30 Sandy Subtidal Sampling ...... 4-31 Sampling Program Schedule, Coordination and Reporting ...... 4-32 CRITERIA FOR DETECTING ADVERSE IMPACTS ...... 5-1 Performance Criteria ...... 5-1 Statistical Analysis of Change ...... 5-1 Assessment Variables ...... 5-4 Intertidal Habitat Feature Class Mapping ...... 5-4 Subtidal Habitat Feature Class Mapping ...... 5-4 Intertidal Assessment Variables ...... 5-5 Subtidal Assessment Variables ...... 5-5 Determination of adverse Impacts ...... 5-7 MITIGATION ...... 6-1 Adaptive Management ...... 6-1 Adaptive Management Framework ...... 6-1 Compensatory Mitigation ...... 6-3

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Habitat Specific Mitigation Plan ...... 6-3 CCC Mitigation Ratios ...... 6-4 Compensatory Mitigation Opportunities ...... 6-4 Functions and Values of Habitat Types(s) To Be Rehabilitated, Enhanced and/or Preserved..... 6-5 Other Mitigation Considerations...... 6-7 Time Lapse Between Impacts And Expected Mitigation Success ...... 6-7 Responsible Parties ...... 6-8 Estimated Mitigation Cost ...... 6-8 REFERENCES ...... 7-1 Appendix A: Special Condition 6 Language, Notice of Intent to Issue Permit, 4-15-0390, California Coastal Commission

Appendix B: Conceptual Habitat Compensatory Mitigation Plan, Broad Beach and Dune Restoration Project, Michael Baker International (July 2017)

Appendix C: Adaptive Management and Monitoring Plan, Moffatt & Nichol. 2017

Appendix D: Exhibit E, Monitoring Implementation Program, General Lease – Beach Replenishment and Protective Structure Use, Broad Beach Restoration Project, California State Lands Commission, 2016

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LIST OF TABLES

Table 2-1: Habitats and Feature Classes Delineated within Broad Beach Survey Area based on Composite Mapping Data Collected between 2014 and 2016 ...... 2-7 Table 2-2: Comparison of Species Recorded at Broad Beach and Potential Reference Sites ...... 2-8 Table 2-3: Summary of Uniform Point Counts (Percent Cover) from MPA Biodiversity Surveys Conducted in 2009 and 2013 at Lechuza Cove Malibu, California...... 2-9 Table 2-4: Percent Cover of Functional Groups and Species within Intertidal Boulder Field (Chambers, 2013) ...... 2-9 Table 2-5: Percent Cover of Subtidal Rocky Reef Functional Groups and Species for Fall 2016 Surveys Conducted in the AoPE (Merkel 2016)...... 2-12 Table 2-6: Physical Attributes and Survey Approach for Rocky Intertidal Sites in the Vicinity of Broad Beach from Northwest to Southeast ...... 2-27 Table 2-7: Intertidal Biodiversity UPC (percent cover) of Functional Groups and Species for Lechuza Point (AoPE) and Sequit Point for the years of 2009 and 2013) ...... 2-35 Table 2-8: PISCO Survey Swath Species List...... 2-40 Table 2-9: Rocky Subtidal Monitoring Sites in the Vicinity of Broad Beach from Northwest to Southeast 2-41 Table 2-10: Percent Cover of Substrate Type and Relief of Rocky Subtidal Monitoring Sites in the Vicinity of Broad Beach (from Pondella et al. 2015b) ...... 2-41 Table 2-11: Abundance and Percent Cover of Indicators from Rocky Subtidal Monitoring Sites in the Vicinity of Broad Beach (from Pondella et al. 2012) ...... 2-42 Table 2-12: Kelp Canopy Historic Maximum Annual Extent in CDFW Beds 16 and 17 (MBC 2016)...... 2-45 Table 3-1: Habitat Components of Interest for Potential Reference Sites ...... 3-4 Table 3-2: Reference Site Selection Matrix ...... 3-5 Table 3-3: Reference Sites for Each Monitored Habitat Element ...... 3-8 Table 4-1: Functional Group and Representative Species Scored during Point Contact Surveys for Rocky Intertidal Sampling using Modified Biodiversity Approach ...... 4-15 Table 4-2: List of Motile Invertebrate Functional Groups Counted in Motile Invertebrate Quadrat Surveys ...4- 16 Table 4-3: Subtidal Rocky Reef Functional Groups, Representative Species, and Substrate Enumerate on Transects ...... 4-24 Table 4-4: Proposed Sampling Schedule First 5 Years (Shaded Cells Indicate Sampling Completed in Accordance with this Monitoring Plan) ...... 4-33 Table 5-1 Mapped Habitat Feature Classes for Assessment and Evaluation. Delta (Δ) values between Impact and Reference sites in each time period will be calculated for each of these variables ...... 5-5 Table 5-2 Rocky Intertidal Evaluation Metrics to be used for Assessment of Project Impact Evaluation. Delta Values between Impact and Reference Sites in each Time Period will be Calculated for each of these Variables ...... 5-6 Table 5-3 Intertidal and Subtidal Sand Beach Evaluation Metrics to be used for Assessment of Project Impact Evaluation. Delta Values between Impact and Reference Sites in each Time Period will be Calculated for each of these Variables ...... 5-6 Table 5-4 Subtidal Metrics to be used for Assessment of Project Impact Evaluation. Delta Values between Impact and Reference Sites in each Time Period will be Calculated for each of these Variables .5-6 Table 6-1: Potential Adaptive Management Actions ...... 6-2 Table 6-2: Mitigation Parties ...... 6-5

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LIST OF FIGURES

Figure 2-1: Broad Beach Regional Setting ...... 2-2 Figure 2-2: Broad Beach AoPE and Extended Beach Monitoring Area ...... 2-5 Figure 2-3: Broad Beach AoPE with Bathymetry, Tidal Elevations, and Subtidal Subtrates ...... 2-6 Figure 2-4: Spatial Extent of Surfgrass in the AoPE based on Fall 2016 Mapping (Merkel 2016) ...... 2-10 Figure 2-5: Frequency of Kelp Canopy Cover within the Broad Beach AoPE for 1989-2014...... 2-15 Figure 2-6: Kelp Canopy Area by Year (1989-2014) within Broad Beach AoPE ...... 2-16 Figure 2-7: Eelgrass within Broad Beach AoPE - 2014, 2016 & 2017...... 2-18 Figure 2-8: Eelgrass Monitoring West of Broad Beach, Merkel & Associates, 2015 ...... 2-20 Figure 2-9: Kelp Canopy West of Broad Beach, MBC Applied Environmental Sciences, 2015 ...... 2-21 Figure 2-10: Historical and Ongoing Monitoring Locations Under Various Programs West of Broad Beach. 2-22 Figure 2-11: Eelgrass Monitoring East of Broad Beach, Merkel & Associates, 2015 ...... 2-23 Figure 2-12: Kelp Canopy East of Broad Beach, MBC Applied Environmental Sciences, 2015 ...... 2-24 Figure 2-13: Historical and Ongoing Monitoring Locations Under Various Programs East of Broad Beach. .2-25 Figure 2-14: Species Richness, Abundance, and Biomass of Beach Macroinvertebrates within MPA Baseline Study Beaches in Fall 2011 (from Dugan et al. 2015)...... 2-38 Figure 2-15: CDFW Administrative Kelp Bed Lease Areas Depicting Location of Beds 17 and 16 (adapted from MBC 2016)...... 2-44 Figure 2-16: Lechuza Kelp Bed from CRKSC in Relationship to the Broad Beach AoPE (adapted from MBC 2016) ...... 2-46 Figure 2-17: Maximum Annual Kelp Canopy by Bed within Broad Beach Study Region based on CRKSC data ...... 2-47 Figure 2-18: Eelgrass Depth Distribution along the Marina del Rey to Ventura County Shoreline from 2015 Southern California Bight Regional Eelgrass Surveys (from Merkel & Associates 2015) ...... 2-48 Figure 3-1: Habitat Reference Site Locations Relative to the AoPE ...... 3-7 Figure 4-1: Habitat Sampling Locations and Transects in the AoPE with 6-month Sand Transport Model ..4-12 Figure 4-2: Habitat Sampling Locations and Transects in the AoPE with 1-year Sand Transport Model ...... 4-13 Figure 4-3: Surfgrass Transects in the Broad Beach AoPE ...... 4-20 Figure 4-4: Rocky Reef Subtidal Habitat Survey Transects in the Broad Beach AoPE ...... 4-25 Figure 4-5: Rocky Reef Subtidal Habitat Survey Transects in the Leo Carrillo/Sequit Point Reference Site. ...4- 26 Figure 4-6: Rocky Reef Subtidal Habitat Survey Transects in the El Pescador Reference Site...... 4-27 Figure 4-7: Rocky Reef Subtidal Habitat Survey Transect Placement and Configuration ...... 4-29 Figure 5-1: Illustration of Patterns of Variation in Simulated Density Data and Resulting Delta (Δ) Values from Paired Sites that Track Each Other (A) Versus Non-tracking sites (B) ...... 5-2

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PHOTOGRAPHS

Photo 2-1: Well developed distribution of eelgrass plants in the AoPE documented in spring 2017...... 2-16 Photo 2-2: Disperse eelgrass community commonly observed in the AoPE and reference sites in 2017. ....2-16 Photo 2-3: Slightly gravelly sand beach – May 2016 (top). Note the low gradient and concentrated flow (right side of top photo) as water runs out of a shore parallel swale between a nearshore beach rise and the rise of the upper beach. This flat beach profile has been observed even when sand is stacked against the base of the revetment – February 2016 (bottom)...... 2-26 Photo 2-4: Boulder/cobble field in partially sanded condition – February 2016 (top); generally scoured condition with ephemeral algal communities – May 2016 (middle); and surfgrass bed in sanded environment – February 2016 (bottom)...... 2-27 Photo 2-5: The Old Stairs site is a southwesterly oriented low bench bedrock intertidal site surrounded by sand beach that intermittently has greater or lesser extents of sanded boulder/cobble environment (top, UCSC photo). The site is an overall small rocky protrusion of bedrock ridges backed by a revetment slope along Highway 1 and small beach features (bottom, Google Earth 2013)...... 2-29 Photo 2-6: The Deer Creek site is a southeasterly oriented flat topped bedrock bench intertidal site (top, UCSC photo) surrounded by sand beach and sandy subtidal environments with some additional rock outcrops in the offshore shallows. The site is an overall small rocky protrusion of bedrock ridges backed by a revetment slope along Highway 1 and small beach features. The actual sampled site is one of a number of small parallel outcrop exposures of a similar nature located in this area (bottom, Google Earth 2013)...... 2-30 Photo 2-7: The Sequit Point site is a southerly oriented bedrock bench surrounded by sand, boulder/cobble, and other bedrock features (top, UCSC photo). The site is the westerly of two prominent points extending seaward within Leo Carrillo State Beach (bottom, Google Earth 2013)...... 2-31 Photo 2-8: The Lechuza Point site is a southerly oriented bedrock bench surrounded by sand, boulder/cobble, and other bedrock features (top, UCSC photo). The site is within the west end of the AoPE and is a primary area of concern in this monitoring program. The site sampled during long-term monitoring program activities is the dominant rocky headland feature located to the west of smaller and lower rocks that dot the westerly portion of Lechuza Cove and which create a mosaic of bedrock reef and active sand channels that are believed to convey sand into and out of Lechuza Cove (bottom, Google Earth 2013)...... 2-32 Photo 2-9: The Point Dume site is a southerly oriented bedrock exposure also comprised of megaclast bedrock that has fallen from the eroding point to the intertidal. Intermixed with the rock is large boulder rubble and transient sand (top, UCSC photo). The site is located at the tip of Point Dume with the bedrock feature continuing offshore to support a headland kelp bed (bottom, Google Earth 2013)...... 2-33 Photo 2-10: The Paradise Cove site is a southeasterly oriented sandstone bedrock uplift terrace (top, UCSC photo). The site is located within Paradise Cove and is protected from all but southerly storms by the prominent Point Dume to the west. The intertidal rock is part of a continuous reef complex of exposed ridges interspersed with sand bottom habitat (bottom, Google Earth 2013)...... 2-34 Photo 2-11: Slightly gravelly sand beach – May 2016 (top). Note the low gradient and concentrated flow (right side of top photo) as water runs out of a shore parallel swale between a nearshore beach rise and the rise of the upper beach. This flat beach profile has been observed even when sand is stacked against the base of the revetment – February 2016 (bottom)...... 2-36 Photo 2-12: Bedrock reef within the AoPE varies from low relief reef, typically found nearshore (top) to isolated rock outcrops, generally more common further to the east of Lechuza Point (middle) to larger rocky outcrops with more complex topographic relief generally most common at the west end of the AoPE off Lechuza Point (bottom)...... 2-39 Photo 2-13: The kelp canopy within Broad Beach reflects the mosaic of expansive and spotty bedrock reef below. While the manifestations of the surface canopy are dependent upon a number of factors, during late summer and fall, most kelp beds are reflected on the water surface (top). The kelp beds within the AoPE are generally moderately open relative to some of the larger beds in the region, although the more extensive beds at the west end of the AoPE do provide considerable structure to the water column (middle). Portions of the AoPE are limited in capacity to support kelp bed expansion due to lack of available substrate. In some cases, the bedrock outcrop is nearly fully defined by a single massive holdfast of giant kelp (bottom)...... 2-43 Photo 3-1: Leo Carrillo has a headlands, cove and trailing beach topology similar to Lechuza Point and Broad Beach and is located only 4 miles upcoast of Broad Beach; however, Arroyo Sequit draining into the cove is much larger than Steep Hill Canyon entering Lechuza Cove (top). The site supports

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partially sanded boulder/cobble beds (top middle) and a bedrock headland with both high and low elevation intertidal rock supporting surfgrass (bottom middle). Intertidal resources experience similar scour and thermal stresses as were noted within Lechuza Cove (bottom)...... 3-9 Photo 3-2: Sequit Point is a platform headland that is topologically similar to Lechuza Point on the headland itself (top). However, Sequit Point lacks a trailing beach; rather it supports a leeward pocket beach. The headland is generally gently sloping to the southwest with a scarped edge that drops vertically to sand below (top middle). The elevation of sand rises and falls against the headland but generally does not reach the elevation of the rocky platform. The site has been used as a PISCO monitoring site and has had biodiversity sampling performed in 2009 and 2013. The headland supports a miex of barnacles, mussels, macroalgae, and a high proportion of bare rock (bottom middle). Rock bolts from this sampling are evident on the point (bottom)...... 3-11 Photo 3-3: El Pescador has a small headland, cove and trailing beach topology similar to Lechuza Point and Broad Beach and is located only 2 miles upcoast of Broad Beach; however, the point does not provide a similar extent of protection as Lechuza. Decker Canyon draining into the area appears similar to the Steep Hill Canyon entering Lechuza Cove (top). The site supports partially sanded boulder/cobble beds (top middle) and a bedrock headland with both high and low elevation intertidal rock supporting surfgrass (bottom middle). Intertidal resources are similar to those noted within Lechuza Cove (bottom)...... 3-12 Photo 3-4: El Matador is located close to the western end of Broad Beach. It does not have a defined headland but rather is defined by a scattering of boulders within the intertidal beach and prominent pinnacles (top and top-middle). The rocky habitat includes both non-persistent and persistent invertebrate species, indicative of variable sanding environments (bottom middle). The beach abuts a vertical bluff on the back beach (bottom)...... 3-13 Photo 3-5: East Zuma Beach has a beach topology similar to Broad Beach and is located approximately 2.5 miles downcoast of Broad Beach (top). The site supports a wide beach (middle) and large back beach that also includes a small dune system (bottom)...... 3-14 Photo 4-1: Ground-truth points from drop-camera. Point confirms habitat feature and substrate for bedrock, boulder/cobble, eelgrass, and sand habitats...... 4-8 Photo 4-2: Biodiversity sampling targets functional groups used in the assessment of intertidal habitat change. The Biodiversity survey protocol includes UPCs, swath surveys and motile invertebrate quadrat counts along multiple transects to allow comparisons with historic sampling events that displayed adequate statistical power to assess changes in intertidal communities...... 4-14 Photo 4-3: Vertical surface on bedrock outcrop showing lower margin of the rock surface supporting crustose coralline surface to be targeted in vertical surface monitoring within the rocky intertidal...... 4-17 Photo 4-4: Measurements are taken using a graduated probe to determine depth of burial of the surfgrass rhizome mat while the density of the leaf canopy are determined by measuring the canopy mat thickness of the un-aggregated leaf layer...... 4-19 Photo 4-5: Typical surfgrass habitat within the AoPE where measurements would be taken to determine depth of burial of the surfgrass rhizomes and canopy mat thickness...... 4-21 Photo 4-6: Interferometric sidescan sonar backscatter mosaic at Broad Beach (2014) illustrating coarse grain sand chutes formed by rips extending perpendicular from shore. These energy features create coarse grain sand concentrations along the beach that generally extend to depths less than -20ft. MLLW...... 4-31

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LIST OF ACRONYMS

ABAPY Average Bed Area Per Year AIC Aikake Information Criteria AMM Avoidance and Minimization Measure AMMP Adaptive Management and Monitoring Plan AoPE Area of Potential Effect ASBS Area of Special Biological Significance BACIP Before-After/Control-Impact Paired BBGHAD Broad Beach Geologic Hazard Abatement District CDPR California Department of Parks and Recreation Caltrans California Department of Transportation CCC California Coastal Commission CDFW California Department of Fish and Wildlife CDIP Coastal Data Information Program CDP Coastal Development Permit CEMP California Eelgrass Mitigation Policy and Implementing Guidelines CMECS Coastal and Marine Ecological Classification Standard Corps U.S. Army Corps of Engineers CRANE Cooperative Research Assessment of Nearshore Ecosystems CRKSC Central Region Kelp Survey Consortium cy Cubic Yards DEM Digital Elevation Model DHREP Dune Habitat Restoration and Enhancement Plan FGDC Federal Geographic Data Committee GENESIS GENeralized model for Simulating Shoreline change GIS Geographic Information Systems IR Infrared LiMPETS Long-term Monitoring Program and Experimental Training for Students LTER Long-Term Ecological Research Project MARINe Multi-Agency Rocky Intertidal Network MBES Multibeam Echo Sounder MHMMP Marine Habitat Monitoring and Mitigation Plan MLLW Mean Lower Low Water MPA Marine Protected Area NIR Near Infrared NMFS National Marine Fisheries Service NOAA National Oceanic and Atmospheric Administration OGPP Offshore Geophysical Permit RCCA Reef Check California Regional Board California Regional Water Quality Control Board, Los Angeles Region SAP Science Advisory Panel SCCOOS Southern California Coastal Ocean Observing System SCI Separate Confidence Interval SCP Scientific Collector’s Permit SCSR South Coast Study Region SIMPROF Similarity Profile Analyses SMCA State Marine Conservation Area SMR State Marine Reserve State Lands California State Lands Commission SWRCB State Water Resources Control Board TM Thermatic Mapper UAV Unmanned Aerial Vehicle UCSB University of California, Santa Barbara UCSC University of California, Santa Cruz UPC Uniform Point Count USEPA U.S. Environmental Protection Agency

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USFWS U.S. Fish and Wildlife Service VHF Very High Frequency

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan INTRODUCTION

BACKGROUND The Broad Beach Geologic Hazard Abatement District’s (BBGHAD) proposed actions include a rock revetment, beach nourishment, and dune restoration project ("Project") at Broad Beach in the City of Malibu in Los Angeles County. The following Project regulatory approvals have been obtained or are in process:

 U.S. Army Corps of Engineers (Corps) – Section 404 Permit pursuant to the Clean Water Act and Section 10 of the River & Harbors Act, including consultations with the U.S. Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) – Environmental Assessment will be issued following finalization of EFH consultation  California Regional Water Quality Control Board, Los Angeles Region (Regional Board) – Section 401 Water Quality Certification and Report of Waste Discharge, approval of a General Construction Activity Storm Water Permit, and any other approvals deemed necessary during the construction entitlement process – in process  California Coastal Commission (CCC) – Coastal Development Permit (CDP) CDP 04-15-0390 approved 10/09/2015, issuance pending compliance with the prior-to-issuance special conditions of the CDP. Permit issuance and commencement of approved development must occur prior to the permit expiration date of 10/09/2017 or by a new date determined by the Commission via an extension application which was submitted by the BBGHAD on 9/13/2017.  California State Lands Commission (State Lands) – State Lands Lease PRC 9364.1 issued on 8/04/2016  California Department of Transportation (Caltrans) – Encroachment Permit Originally issued in 2014, resubmittal to Caltrans occurred in spring 2017, responses to City of Malibu and Caltrans comments in process  County of Los Angeles Department of Harbors and Beaches – Encroachment Permit – Will be issued when project start date has been finalized

The beach nourishment aspect of the Project is limited to direct sand placement in the area between 31380 Broad Beach Road at the upcoast end and 30708 Pacific Coast Highway at the downcoast end (eliminating direct sand nourishment between Point Lechuza and 31380 Broad Beach Road). The language in CDP 4-15- 0390 limits the quantity of sand nourishment deposition to 300,000 cubic yards (cy) of sand during the first year, and as needed according to objective triggers, allowing periodic small-scale interim nourishments involving up to 75,000 cy of sand and major nourishments involving up to 300,000 cy of sand through 10/09/2025. In addition, the permit allows for periodic backpassing of no more than 25,000 cy once per year according to objective triggers over the same permit period. The permit allows for beach nourishment of imported sand of a coarser grain size (D50 0.25 mm to 0.6 mm) than represented by the native sand along Broad Beach (D50 0.25 mm). Regulatory Agency Monitoring Need While numeric modeling and analysis conducted for the Project suggests a particular outcome of sand placement, many factors influence how sand moves within the beach environment. Therefore, the ultimate temporal and spatial distribution of Project sand cannot be fully determined through modeling. This is especially true relative to the behavior of sand and water around fine-scale topology of headlands and biotic dampeners, such as kelp forests. Considering Project and environmental uncertainties and modeling weaknesses, empirical observation through time of the beach and adjacent areas is needed by regulatory agencies to more fully understand the distribution of Project sand from the initial placement and authorized maintenance and renourishment activities.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Because the nourishment sand is coarser than native beach sand, concerns have been raised that the sand may have effects on marine resources beyond those of increased burial or scour. It remains unclear if increasing mean sediment grain size, as allowed under the CDP and other permit conditions, will result in greater or lesser scour effects or more persistent burial periods within marine habitats in the Project area. Biological resource monitoring, in combination with monitoring of physical site conditions and collection of sand samples for grain size analysis, will evaluate Project influence on scour and burial rates (including durations) caused by the augmentation of sand on the beach with material coarser than the native grain size, and how this may impact the valuable marine ecosystems located and at near Broad Beach, which are part of the Point Dume State Marine Conservation Area..

For beach, intertidal and subtidal soft and hard bottom environments, concerns exist that the change in beach grain size, as well as increased burial, scour and turbidity, may alter the native biota and habitat characteristics. For this reason, the CCC has required the BBGHAD to conduct rigorous marine habitat monitoring as part of the Project to identify and quantify the actual Project impacts, develop adaptive management measures that may be taken to reduce impacts, and should it be necessary, carry out compensatory mitigation appropriate to offset adverse impacts.

The CCC’s Notice of Intent to Issue CDP 4-15-0390 Section III, Special Condition 6 requires the BBGHAD to develop a long-term marine habitat monitoring and mitigation plan (MHMMP) describing the sampling methodology, analytical techniques, and methods for detecting adverse impacts associated with the beach nourishment element of the Project. In addition, the condition includes reporting requirements and specifies that, if adverse impacts are identified, compensatory mitigation will be required. The CDP Special Condition 6 language is provided in Appendix A. The MHMMP also addresses the avoidance and minimization measures for biological resources identified by the State Lands, specifically AMM MB-2b and AMM TBIO- 3c. Finally, the MHMMP seeks to meet the Corps’ special condition requirements once identified, as well as USFWS and NMFS requirements.

The MHMMP is considered to be a living document which will be refined and updated as more Project site and reference site information is gathered. All modifications or changes to the MHMMP at any time require agency review and approval Approaches to Meeting Monitoring Objectives This document serves as the MHMMP or Plan associated with the Project. The following sections outline the approaches proposed to meet the CCC’s permit requirements as well as those of other regulatory agencies with regulatory jurisdiction over the project.

The MHMMP is intended to provide a framework to identify reference site selection, sampling methodology, and impact analysis methodology. A general adaptive management framework is included to inform ongoing management and to allow for adjustments to the nourishment program as informed by new insight guided by the BBGHAD Project team, CCC (and Science Advisory Panel [SAP]), Corps (and NMFS), and other consulting resource agencies. This may include enhancement of the existing plan as appropriate for better informing management decisions, relaxation of the existing plan to avoid unnecessary costs, or modifying the plan to track with adaptive management undertaken within the Project. The MHMMP is also designed to meet the Corps’ objective of monitoring beach profiles and jurisdiction to determine any loss of or impacts to waters of the United States (Section 10 and Section 404), as well as any related loss of aquatic resource functions, as a result of the Project rock revetment and sand placement. The Plan will also address requirements pertaining to marine resources in compliance with direction from the NMFS and USFWS. Monitoring of non-marine resources (e.g. dune habitat), avian resources, and Trancas Creek will be addressed in other plans, including the Dune Habitat Restoration and Enhancement Plan (DHREP) and the Adaptive Management and Monitoring Plan (AMMP). However, all monitoring parties involved will be coordinating as identified in the communications plan as outlined in Section 1.3.

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The monitoring program has been developed through consideration of existing monitoring data collected under other studies, pilot study information specific to the Broad Beach Project, and statistical design criteria outlined in Special Condition 6 of the CDP. Because of inherent uncertainties related to limited baseline data for the site as well as applicable data sets' focus on the types of impacts anticipated from a coarse grain sand nourishment project, the initial monitoring program has incorporated both a greater number of reference sites and greater replication than may ultimately be determined to be required to meet statistical power objectives. However, the program allows for revisiting the reference sites and replication levels as the data are collected and evaluated with the expectation that reference sites or replication may be reduced when it is determined that such reduction of monitoring scope does not jeopardize the functions of the monitoring program. Any revisiting of reference sites or replication levels would require input and approval from both state and federal agencies holding jurisdiction in the Project site. SCIENCE ADVISORY PANEL CDP Special Condition 6 calls for the creation and operation of a SAP to guide the development of the MHMMP and to advise the CCC's Executive Director regarding final plan approval. The SAP is also charged with reviewing the monitoring results and annual reports, advising on the Project status, and specifying conclusions and recommendations for potential adaptive management actions, as well as specific habitat mitigation and monitoring plans should such become necessary as compensation for Project impacts.

The SAP for the Plan is a panel of three marine scientists with expertise on nearshore habitats, including at least one member with expertise in experimental design and biostatistics. The Permit tasks the SAP with reviewing and guiding development of the final marine habitat monitoring and mitigation plan - including the selection of reference sites, sampling methodology, analytical techniques, criteria for determination of adverse impacts, and mitigation options for the various marine habitats. The SAP shall also review the monitoring results and annual reports as they come in and advise the CCC's Executive Director (and consult with State Lands staff) regarding Project status, coupled with conclusions and recommendations for potential adaptive management actions. If marine habitat monitoring demonstrates that adverse impacts have occurred to one or more marine habitats, the SAP shall review and guide development of specific habitat mitigation plans. SAP members include:

 Pete Raimondi (SAP Chair): Professor and Department Chair at the University of California, Santa Cruz (UCSC) - Ecology and Evolutionary Biology Department, Institute of Marine Sciences.  Robert Hoffman (SAP Member): Formerly Assistant Regional Administrator for the Habitat Conservation Division of the Southwest Region of the NMFS (retired 2011).  Mark Page (SAP Member): Research Biologist at University of California, Santa Barbara (UCSB) - Marine Science Institute.

In addition to the SAP, this Plan has benefited from collaborative efforts and contributions of multiple resource and regulatory agency representatives participating in SAP coordination meetings and reviews. These agencies and representatives include: Jonna Engle (CCC), Lesley Ewing, and Lauren Garske-Garcia (CCC); Bonnie Rogers, Daniel Swenson (Corps); Bryant Chesney (NMFS);Melissa Scianni (U.S. Environmental Protection Agency [USEPA]); Bill Paznokas and Kelly Schmoker (California Department of Fish and Wildlife [CDFW]); Jason Ramos (State Lands); L.B. Nye (Regional Board); and Project engineers and planners Russ Boudreau, Tonia McMahon, Chris Webb, and Stephanie Oslick (Moffatt & Nichol). Additionally, technical staff at the U.S. Geological Survey and U.S. Fish and Wildlife Service were reached out to on numerous occasions but have opted not to participate in the consultation process thus far. COMMUNICATIONS PLAN The MHMMP requires regular communication with the SAP and agencies regarding information collected and data analyses. Communication will ensure that SAP and agency participants remain apprised of plans

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan and schedules for backpassing and sand renourishment based on established triggers. The parties will be provided monitoring schedules, progress, and data results as well as proposed adaptive management opportunities for consideration.

The communications process will additionally allow for coordination between the various permit-required monitoring programs, including the physical condition monitoring elements per CDP special Condition 4, dune restoration monitoring elements per CDP Special Condition 5, and marine habitat monitoring elements per CDP Special Condition 6. Communication will be facilitated as follows.

1) Email Correspondence 2) Annual Monitoring Reports 3) Semi-annual Coordination Meetings Centralized Data Management System A centralized data repository will be set up for the project and will be maintained by the BBGHAD technical consultant, Moffatt & Nichol. This repository will sit on a Newforma® platform. In addition to storing project data, the Newforma® program keeps a log of Transmittals arranged by Transmittal number, including the associated files, originator, distribution list, metadata, and email correspondence. The files and Transmittals stored are organized by various fields, including file name, file type, data and words included in the file itself, file author, among others. The files themselves are stored on the M&N server in a structured, numerical file system. This searchable file structure allows easy archival, access, and retrieval of files for the Project from any location, including at remote field sites. Newforma® is fully interfaced with Microsoft Exchange via Outlook, giving the project team the ability to file and manage emails directly from Outlook into Newforma®. Newforma® is a comprehensive solution for managing all forms of project information in one place—documents, drawings, PDFs, images, and all emails, regardless of the sender or recipient. Key features of the system include:  Ability to coordinate work with all partners  Ensure all team members are working with current versions of all documents  Know what was issued to whom, and who has – and who has not – downloaded files  File and find all project related email  Improve management of meeting minutes and action items  Manage project images, drawings, reports and other data

Email Correspondence Project team members will receive email notifications when all monitoring related data, including final reports, metadata (raw survey results), meeting minutes, etc. are uploaded to the Newforma® project folders. Physical condition information to be gathered by BBGHAD consultants in accordance with the approved AMMP (required by Special Condition 4 of the CDP and various State Lands Avoidance and Minimization Measures (AMMs) includes the following:

 Beach profile survey data,  Beach berm width,  Transect survey data,  Wetted bound surveys,  Aerial photographs, and  Trancas Creek Mouth condition.

Dune observations and monitoring will be conducted in accordance with the approved final DHREP required under Special Condition 5 of the CDP as well as State Lands AMMs, Corps’ identified permit conditions,

November 2017 1-4

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan and USFWS Biological Opinion. The findings from these efforts will be circulated by the BBGHAD team to all agency representatives with recognition of the fluid nature between marine, beach and dune habitats as well as their interrelatedness. Proposed maintenance activities such as backpassing and interim nourishments will also be informed by the results of pre-construction field monitoring before any maintenance activities occur, as required under Special Condition 7, including surveys to be conducted by an environmental resources specialist for western snowy plover and California grunion. Sharing of dune and pre-construction monitoring results and findings will facilitate consultation with the marine habitat monitoring team, particularly in regards to performance of nourishment material grain size. Interim monitoring results will be shared with agency staff as promptly as possible to facilitate early review in the event that habitat changes are detected during field work. Those team members working across focus areas will be notified when new data sets in all overlapping areas have been uploaded to Newforma®. Monitoring Reports The BBGHAD will submit annual monitoring reports to agencies prior to December 31 of each monitoring year. The reports will be cumulative including results and analyses from the prior years’ monitoring. This schedule should allow an opportunity to fully process and analyze collected data for each report. Reports are intended to be cumulative in structure such that each report includes data and analyses that builds on the prior monitoring results with temporal data plots and analyses. Data for the monitoring year will be provided as appendices to the report such that all monitoring data will be made available through the accumulation of annual reports.

Reports will be prepared and submitted as draft reports by December 31 of each monitoring year. Every effort will be made by the SAP and the agencies to conduct report review during the month of January and to provide timely feedback. If feasible, the winter semi-annual coordination meeting will be held in January however schedule challenges and logistics may result in the meeting being held in February.

Comments received shall be considered and the annual report shall be finalized and resubmitted to the SAP and agencies as final by the end of February. Approvals required by CCC’s Executive Director and other agency staff will be secured before any further work occurs on the site.

Two comprehensive reports pertaining to the MHMMP as well as the other Special Condition monitoring requirements (dunes, AMMP, etc.) will be prepared during the monitoring period, at 5 and 10 years following initial sand placement, in accordance with final state and federal agency conditions. The comprehensive reports will provide a full review of positive and negative deviations in habitat conditions as compare with reference site expectations. Upon receipt of these reports, the CCC will assess any potential mitigation requirements beyond the adaptive management recommendations. Semi-Annual Coordination Meetings In January or February of each monitoring year, the winter coordination meeting will be held to review the MHMMP monitoring results from the prior season (to review the monitoring results, discuss findings, and consider any needs for adaptive management or monitoring plan modifications), review the physical performance of the beach and data from the physical monitoring program, review the dune habitat status, and to discuss any triggers for renourishment or backpassing that have been met or are anticipated to be met in the subsequent period. Should agency representatives indicate that additional coordination meetings are required, a second meeting or teleconference may be arranged in July or August to address spring season monitoring results.

Coordination meetings will be used as a forum for discussion of any proposed adaptive management actions or monitoring program changes warranted based on physical and biological monitoring results, program objectives, and cost controls. Agency staff will make determinations regarding approval of any proposed adaptive management measures or the need for compensatory mitigation and, subsequent to the coordination

November 2017 1-5

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan meeting, seek approval for these determinations by their management staff. These meetings would also serve as a forum for discussion of mitigation opportunities that may be identified by the BBGHAD, agencies, or SAP members that may provide strategic planning opportunities ahead of action triggers for compensatory mitigation.

It is anticipated that the meetings will be all day meetings held in Long Beach or nearby and would be generally structured by an agenda as follows:

 Overview of beach program status and permit conditions compliance  Beach restoration performance and physical monitoring results  AMMP adjustments  Dune restoration and monitoring program results  Marine habitat monitoring results  Adaptive management planning MONITORING PROGRAM AUTHORIZATION REQUIREMENTS The Broad Beach MHMMP involves a combination of passive, active, and consumptive (collection of beach samples or benthic infauna) sampling within areas of various federal and state jurisdictions. This sampling activity is regulated by multiple agencies and the completion of work under this program must be conducted in adherence to the requirements and permitting of regulatory agencies. In particular, the following requirements are to be met:

 Offshore Geophysical Permit (OGPP) – All acoustic remote sensing activities under this plan shall be conducted under a valid State Lands OGPP. This permit has conditions on periods of operations, notification requirements, and requirements for observers and separate reporting. Under the OGPP, approval is also required from the CDFW for operations within a designated Marine Protected Area (MPA).  Scientific Collector’s Permit (SCP) – CDFW, Fish and Game Code Section 1002 and Title 14 Sections 650 and 670.7, requires that a SCP is required to take, collect, capture, mark, or salvage, for scientific, educational, and non-commercial propagation purposes, mammals, birds and their nests and eggs, reptiles, amphibians, fishes, and invertebrates. The collection, possession, transplantation or propagation of rare, threatened or endangered plants or manipulation of their habitat is not included in the SCP and requires a Rare, Threatened or Endangered Plant Collecting Permit or Plant Research Permit. Take of threatened or endangered species incidental to an otherwise lawful activity requires a Section 2081(b) permit. The SCP will require an application and fee and need to be obtained by the scientists conducting the monitoring. Consumptive sampling work will take place at all sampling locations, including MPA sites.  Unmanned Aerial Vehicle (UAV) Operations Approval – The Angeles District of California Department of Parks and Recreation (CDPR) will need to issue a special event permit authorizing the work. This authorization will require insurance naming State Parks as additionally insured and approval of the UAV pilot’s qualifications. Work will require application fee payment and schedule coordination to avoid conflicts with other Special Events.

November 2017 1-6

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan EXISTING CONDITIONS

Broad Beach is located on the Malibu coastline west of Point Dume within the partial wave shadow of the Northern Channel Islands on a narrow continental shelf. The Santa Barbara Channel shipping lanes lie approximately 6 miles off shore in this area. Above the shore is the south slope of the Santa Monica Mountains (Figure 2-1). The south face of the Santa Monica Mountains drains to the Pacific Ocean through a number of small simple watersheds draining a few hundred to a few thousand acres.

Broad Beach is at the easterly end of a south facing shoreline west of Point Dume and defined by small rocky headlands, shallow pocket coves, and short trailing beaches. West of Broad Beach, headland and trailing beaches are developed to different extents, but none of the pocket coves are as well defined as that of Lechuza Cove, east of Lechuza Point. Lechuza Point and Cove support rocky marine habitats within close proximity to Broad Beach and may be potentially affected by the Project work. At the easterly end of Broad Beach is the large Zuma Beach, which curves from a predominantly southerly exposure to a predominantly westerly exposure over its 2.75-mile length. The easterly end of Zuma Beach is anchored by the large Point Dume headlands at the northeastern end of Santa Monica Bay.

While coastal processes dominate the physical influences acting within the Broad Beach area, fluvial inputs also play a lesser role. Within Lechuza Cove there is an outlet from the 300-acre Steep Hill Canyon watershed that drains a canyon from the north side of Highway 1. This drainage feature serves as the historic source of a low relief boulder/cobble field that forms the westernmost end of hard bottom features found in Lechuza Cove. To the east of this boulder/cobble field, rocky features are generally limited to widely scattered isolated bedrock outcrops that exist as boulder-like features on the low beach and shallow subtidal environment. The easterly end of the Project is located near the Trancas Creek mouth. The 4,400-acre Trancas Creek watershed drains to a seasonally closed lagoon between Broad Beach and Zuma Beach. Trancas Creek occasionally exports coarse gravels and sand, such as occurred during high flows during the 2004-2005 winter. However, in general, the discharges from Trancas Creek are principally finer sediments with coarse sediment deposits building in bars at the upper end of the Trancas Creek Lagoon. These bars are ultimately exported to the beach during episodic flood events.

The Project’s Area of Potential Effect (AoPE) is located within the Point Dume State Marine Conservation Area (SMCA), and also within a designated Area of Special Biological Significance (ASBS) (Mugu Lagoon to Latigo Point ASBS). The AoPE principally consists of State Tidelands and Waters of the State, as well as waters of the United States, including Special Aquatic Sites. Please note that the AoPE has no connection with Section 106 of the National Historic Preservation Act.

November 2017 2-1

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Santa Monica Mountains

Lechuza Cove

Zuma Beach

Figure 2-1: Broad Beach Regional Setting

November 2017 2-2

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan BROAD BEACH PROJECT AREA OF POTENTIAL EFFECT The Project involves placement of sand within a discrete footprint along an approximately mile long segment of Broad Beach. From this placement footprint, sand is expected to migrate to a greater or lesser extent along the shoreline and seaward of the fill placement area. The BBGHAD modeled the extent of sand migration using the Corps’ Coastal Engineering Research Center GENEralized model for Simulating Shoreline change (GENESIS) model. The GENESIS model predicts the shift in shoreline position at mean sea level in response to a number of variable factors, including shoreline conditions, wave environments, sediment characteristics and project modifications. From the model, sediment is expected to spread from the initial placement footprint with a predominant, but not exclusive, movement in the downcoast direction (Moffatt & Nichol 2014). Some movement is predicted into Lechuza Cove, with a diminishing footprint and depth of fill over time. Finally, little movement of sand is predicted directly offshore. The GENESIS model used a wave climate from the 2000-2009 period to drive model predictions. It should be noted that more or less extreme wave environments may result in differing outcomes from those predicted by the models. As an example, under the 2015 wave climate, eelgrass beds at Broad Beach were damaged below the generally estimated depth of closure under the modeled wave climate. For this reason, it is important under any assessment framework that anomalous or directionally trending shifts in wave conditions be considered relative to potential for unanticipated sand movement or biological effects.

Based on the modeled extent of sand movement and the estimated depth of closure of -30 feet MLLW, a AoPE was defined for the Project. The AoPE was defined by vertical and horizontal limits selected to ensure that they were likely to encompass the detectable effects of the Project, even considering uncertainties in predictive modeling.

The AoPE should be appropriately defined to ensure scaling appropriate to capture the extent of potential impact, while avoiding possible impact signal dilution by over sizing of the effects assessment area. While the numeric modeling provides one tool to facilitate establishment of an appropriate AoPE for the project, empirical observations of sediment movement under extreme wave environments provides a second important tool in this endeavor. With the larger sand grain size proposed, it is expected that movement of sand will be less than with the finer native sand and that expectations of vertical transport can reasonably be restricted to the maximum depths of sand movement observed during the extreme conditions of 2015. Other observations suggest that sand movement to the west may be at least partially constrained by the seaward subsurface extension of the Lechuza Point rocky headland. This is based on observations of offshore sand chutes along the easterly margin of the headland but not the westerly margin. The numeric model suggests a continual long-shore transport of sand to the east towards Point Dume. However, with greater distance from the Project, a greater dilution of Project sand by native sand is expected and a lessening of Project physical and biotic signal. Based on the observations and predictions, the following outlines the selected extents of the AoPE.

The upper vertical limit of the AoPE was established at the +10 foot NAVD88 contour. This contour is approximately 2.5 feet above the highest high tide and is generally synonymous with rip rap revetment along the developed shoreline, native bluff rock within Lechuza Cove, and a sand berm at the mouth of Trancas Creek. The seaward limit of the AoPE was extended to a depth of the -50 foot NAVD88 contour. This depth is 20 feet below the estimated depth of closure, but was selected as a limit that captures the entire nearshore shallow rocky habitat as well as the full extent of kelp beds and eelgrass resources present off Broad Beach. Based on the onsite baseline data in hand, the upcoast limit of the AoPE was set at 600 feet west of the rocky headland of Lechuza Point, while the downcoast limit of the AoPE was set at 600 feet from the eastern end of the beach fill. This easterly limit includes the mouth of Trancas Creek and the westerly limit of County groomed Zuma Beach (Figure 2-2).

Considering the beach nourishment sand is expected to migrate from the initial placement area, the CDP contemplates potential for effects to beach biota both upcoast of the fill within Lechuza Cove, and down coast of the Project beach on to Zuma Beach. Two sites of concern occur within the AoPE or immediately

November 2017 2-3

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan adjacent to it. Lechuza Cove occupies an area immediately west of the proposed sand placement site within the AoPE and Zuma Beach West is adjacent to the AoPE and defined as an equal length of beach as the Project fill beach (approximately 0.95 miles) and extends from the westernmost Zuma Beach parking lot, located to the east side of the Trancas Creek mouth, easterly along Zuma Beach (Figure 2-2).

November 2017 2-4

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan July 2017

Figure 2-2: Broad Beach AoPE and Extended Beach Monitoring Area

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan July 2017

Supratidal

Figure 2-3: Broad Beach AoPE with Bathymetry, Tidal Elevations, and Subtidal Subtrates

November 2017 2-6

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan August 2017

Marine Habitats Within the Broad Beach Area of Potential Effect In total, the AoPE encompasses 319.54 acres and includes a broad array of marine habitats and associated species. Habitat within the AoPE is defined on the first order by elevation (supratidal, intertidal, and subtidal), in the second order by substrate, and lastly by biological communities. Individual substrate types and some biological resources (e.g. eelgrass, beach wrack, kelp canopy) defined in this MHMMP as “feature classes” are effectively mapped using remote sensing and the spatial extent of these feature classes within the AoPE has been documented to establish existing conditions. Feature class (e.g. bedrock, boulder/cobble, sand, eelgrass, etc.) spatial extent in conjunction with site specific biological characterizations, quantifying biological species density and diversity, provides comprehensive information on individual habitats (e.g. Sand Beach, rocky intertidal, rocky subtidal, etc.). Habitat nomenclatures have been assigned using the prescribed order consistent with the Coastal and Marine Ecological Classification Standard (CMECS) hierarchy as a mapping convention (Federal Geographic Data Committee [FGDC] 2012) to the extent possible.

For the marine habitats present within the AoPE, the tidal elevation mapping has been divided into three zones: supratidal, intertidal, and subtidal (Figure 2-3). Feature classes, substrate types and habitat forming communities (eelgrass and giant kelp canopy) have been quantified in a composite mapping effort to present the maximum potential extents. Biotic communities (species) composed of perennial or ephemeral functional groups or species (e.g., barnacles, mussels, persistent red algal beds, fucoid algal beds, Egregia menziesii, and ephemeral green algae) have not been mapped.

With the caveats provided above, it is useful to consider the general extent of habitat and feature classes within the AoPE. Table 2-1 summarizes the composite extent of feature classes mapped between 2014 and 2016. In the current mapping baseline, the supratidal fringe is principally used to distinguish the shoreward limits of the marine habitats present in the AoPE. However, post-Project implementation, the supratidal area of the placed beach would be expected to expand at the spatial expense of intertidal beach.

Table 2-1: Habitats and Feature Classes Delineated within Broad Beach Survey Area based on Composite Mapping Data Collected between 2014 and 2016 Base Habitat Habitat Forming Habitat Substrate Species Overlay* (Acres) (Acres) Supratidal (Marine: Nearshore) Bedrock (Geologic Substrate: Rock Substrate) 0.03 - Rip Rap (Anthropogenic Substrate: Anthropogenic Rock) 0.52 - Boulder/Cobble (Geologic: Unconsolidated Substrate) 0.01 - Slightly Gravelly Sand (Geologic: Unconsolidated Substrate) 0.58 - Supratidal Total 1.14 0.00

Intertidal (Marine: Nearshore) Bedrock (Geologic Substrate: Rock Substrate) 1.01 - Rip Rap (Anthropogenic Substrate: Anthropogenic Rock) 1.98 - Boulder/Cobble (Geologic: Unconsolidated Substrate) 1.37 - Slightly Gravelly Sand (Geologic: Unconsolidated Substrate) 45.17 - Surfgrass Bed (May-June 2016) (Biotic: Seagrass Bed) - 0.07 Intertidal Total 49.53 0.07

Subtidal (Marine: Nearshore) Bedrock (Geologic Substrate: Rock Substrate) 25.34 - Boulder/Cobble (Geologic: Unconsolidated Substrate) 3.57 - Slightly Gravelly Sand (Geologic: Unconsolidated Substrate) 239.96 - Canopy-Forming Algal Bed (Kelp Canopy 1989-2014) - 37.38 Eelgrass Beds (2014-2015) - 7.32

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan August 2017

Base Habitat Habitat Forming Habitat Substrate Species Overlay* (Acres) (Acres) Subtidal Total 268.87 44.70 Broad Beach AoPE Total 319.54 44.77 Within the AoPE, the supratidal zone (above the intertidal and subject to wave slash) habitat covers approximately 1.14 acres and is comprised of predominantly rip rap revetment and secondarily steep native bedrock headlands, boulder/cobble, and upper sand beach (Table 2-1, Figure 2-3). In general, the supratidal habitat is relatively narrow and diverse with typical supratidal beach habitat (dunes and dry beach) mostly limited to the far eastern extent of the AoPE, near the outflow of Trancas Creek. The supratidal habitat in the AoPE is dominated by rip rap and steep bedrock/sedimentary foreshore that supports few persistent marine biotic communities and only limited terrestrial vegetation based on site specific pilot surveys (Chambers Group Inc. 2012, Merkel 2014, and WRA 2011)

Below supratidal elevations, intertidal habitat within the AoPE encompasses 49.53 acres and is comprised primarily of sand and, in much smaller proportions, isolated boulder/cobble fields, rip rap, and bedrock at Lechuza Point (Table 2-1, Figure 2-3). Biotic communities of intertidal sand beach habitat are well documented throughout southern California and consist of mostly infaunal invertebrates (e.g. decapods, amphipods, annelids, and bivalves). Baseline data collected during pilot studies (Merkel 2016) documented species richness (number of species), abundance, and grain size similar to that of nearby beaches, based on comparisons with South Coast MPA monitoring data (Table 2-2) as reported in Dugan et al. 2015.

Table 2-2: Comparison of Species Recorded at Broad Beach and Potential Reference Sites Broad Beach Leo Carrillo Dume Cove Species Richness (number) (May 2016) * (MPA 2015) (MPA 2015) Total 16 49 41 Tidal Species 16 25 17 (minus Terrestrial Assemblage)

Tidal Species (minus Terrestrial 16 18 10 And Wrack Assemblage) *no wrack line or dry beach present Biotic communities of the AoPE intertidal habitat associated with boulder/cobble and bedrock are diverse and moderately abundant based on data collected at Lechuza Point as part of South Coast MPA Biodiversity surveys (Biodiversity Surveys) conducted in 2009 and 2013 (Table 2-3). The survey locations included both the prominent bedrock headland at Lechuza Point and boulder/cobble habitat within Lechuza Cove. Additionally, Chambers (2013) conducted an intertidal pilot study of the AoPE in 2013 at Lechuza Cove that incorporated bedrock and boulder/cobble field surveys. Both of the Chamber 2013 surveys results displayed a low percent cover of sessile invertebrates (mussels, barnacles, and anemones) and a relatively high percent cover of both ephemeral and persistent algal assemblages (Ulva spp., red algae, and Eisenia menziesii) compared to the nearby MPA survey sites (Table 2-4). Differences in the surveys are accounted for by the fact that the Chambers 2013 survey did not sample the main bedrock headland that contains dense aggregations of sessile invertebrates compared to the lower lying bedrock extrusions and bolder/cobble habitat exposed to wave and sanding disturbance. In each of the site-specific surveys, swath (transect) counts were conducted to enumerate motile invertebrates with the most abundant species including various crab species, sea urchins, and sea stars. No abalone were observed during either of the surveys.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan August 2017

Table 2-3: Summary of Uniform Point Counts (Percent Cover) from MPA Biodiversity Surveys Conducted in 2009 and 2013 at Lechuza Cove Malibu, California.

2009 2013 2009 2013 Functional Group/Species Percent Percent Counts Counts Cover Cover Anemone 47 4.1 75 6.3 Articulated Coraline 29 2.5 74 6.2 Barnacles 116 10.0 128 10.7 Brown Alage 7 0.6 6 0.5 Diatoms 1 0.1 0 0.0 Deep Pool 0 0.0 147 12.3 Egregia menziesii 172 14.9 76 6.3 Endocladia muricata 15 1.3 1 0.1 Encrusting Coraline 1 0.1 18 1.5 Limpets 6 0.5 8 0.7 Littornia spp. 25 2.2 1 0.1 Megabalanus spp. 0 0.0 1 0.1 Mytilus californianus 191 16.5 149 12.4 Nautillna spp. 1 0.1 0 0.0 Other Substrate 0 0.0 2 0.2 Phragmatopoma californica 70 6.1 105 8.8 Pisaster spp. 6 0.5 3 0.3 Pollicipes polymerus 10 0.9 14 1.2 Red Algae 80 6.9 110 9.2 Rock 91 7.9 211 17.6 Sand 257 22.3 46 3.8 Septifer 2 0.2 4 0.3 Sponge 0 0.0 1 0.1 Surfgrass 7 0.6 7 0.6 Tar 0 0.0 1 0.1 Tegula spp. 2 0.2 0 0.0 Tetraclita rubecens 6 0.5 4 0.3 Ulva spp. 13 1.1 4 0.3 Worm 0 0.0 4 0.3

Table 2-4: Percent Cover of Functional Groups and Species within Intertidal Boulder Field (Chambers, 2013) Boulder Field Percent Cover Functional Group or High Mid Low Species Zone Zone Zone Anemone 0.0 6.8 0.0 Bare Boulder 79.6 70.5 47.7 Barnacle 6.8 0.0 0.0 Egregia menziesii 0.0 11.4 12.5 Fleshy Red Algae 0.0 3.4 35.2 Green Algae 2.3 8.0 0.0 Phylospadix spp 0.0 0.0 3.4 Porphyra spp (Ephemeral Red 3.4 0.0 0.0 Algae) Bare Sand 7.9 70.5 47.7 Turf Red Algae 0.0 0.0 1.1

November 2017 2-9

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan August 2017

Transitioning from the intertidal to the subtidal surfgrass (Phyllospadix spp.) occupies exclusively rocky habitat within the surf zone and shallow subtidal where sand deposition and erosion is annually and seasonally variable. Surfgrass in the AoPE is confined to rocky areas associated with Lechuza Cove, based on Merkel 2016 mapping results (Figure 2-4). The surfgrass is distributed as small beds ranging in depth from 0.0 ft to about -12 ft MLLW and primarily occurs in association with the tops of rocks, pools and creases of bedrock extrusions at or adjacent to Lechuza Point and on boulders and bedrock extrusions to the east in Lechuza Cove. Some small patches of surfgrass have been documented up to 800 ft. east of Lechuza Point on more isolated boulders/bedrock extrusions. Surfgrass specific survey efforts were conducted in spring 2017 within the AoPE and regionally that evaluated the depth range, density, and spatial extent of surfgrass communities. Surfgrass survey mapping and surveys documented mostly non-continuous and dispersed surfgrass communities in the AoPE compared to potential reference sites. Intertidal survey data (Table 2-3 and Figure 2-4) provides some degree of additional historic data on the upper extent of surfgrass habitat and its persistence in the AoPE.

Figure 2-4: Spatial Extent of Surfgrass in the AoPE based on Fall 2016 Mapping (Merkel 2016)

November 2017 2-10

Final Broad Beach Marine Habitat Monitoring and Mitigation Plan August 2017

Similar to the intertidal, subtidal feature class mapping within the AoPE has been conducted using a combination of remote sensing and field based survey techniques. The subtidal habitat contains two distinct and important biotic feature classes, eelgrass (Zostera pacifica) and giant kelp (Macrocystis pyrifera), that are easily delineated by use of remote sensing methods. The most comprehensively mapped biotic feature class of the subtidal habitat throughout California is giant kelp canopy extent, collected by the CDFW as part of the Kelp Consortium Survey program that has data extending from 1989 to present. Changes in regional spatial extent of kelp canopy are presented later in this section and temporal and spatial changes are presented in a table and figures to highlight relative changes in the AoPE.

The subtidal substrate within the AoPE is comprised of bedrock, boulder/cobble, and sand with the majority of rock substrate occurring in the western portion of the AoPE and associated with Lechuza Point (Figure 2-3). Similar to the intertidal habitat, the subtidal habitat is dominated by sand that comprises 90 percent of the subtidal habitat in the AoPE, based on 2014 and 2016 mapping efforts (Table 2-1 and Figure 2-3). The remaining portion of the subtidal habitat substrate is comprised of 9.8 percent bedrock and just 0.2 percent boulder/cobble substrate (Table 2-1). Subtidal bedrock extrusions occur as eroded reef structures from the intertidal to shallow subtidal (< 20 ft. MLLW) in the form of low lying reef structure or outcrops of various sizes that are generally steep-sided pinnacles in form and extend to differing heights above the sand. The low lying bedrock and toes of the rock outcroppings found in the shallow subtidal are generally seated or covered in sand, rather than being associated with a continuously exposed bedrock platform. The transition area between the intertidal and shallow subtidal (surfzone) experiences changes in sand deposition/erosion on both a weekly and seasonal time scale that can greatly affect the extent of exposed rock substrate at any one time. The subtidal bedrock (rocky reefs) support a wide spectrum of biota associated with giant kelp forests including fish, invertebrates, and alga that are both ephemeral and perennial. The spatial extent, persistence, abundance, and vigor of the biotic communities within the subtidal are contingent on seasonal and regional oceanographic patterns, depth and biotic interactions among native and non-native species.

The algal communities associated with the rocky reefs are most notably characterized by surface canopy forming giant kelp and secondly by large sub canopy stipate alga such as Cystoseira osmundacea, Eisenia arborea, Sargassum muticum, and others. Benthic understory alga including foliose red algae, articulated coralline, and encrusted coralline algae are the most common constituents within the algal communities based on surveys conducted in the AoPE (Table 2-5). Intertwined with the algal community of subtidal rocky reefs are sessile invertebrates that include a diverse group of organisms such as colonial bryozoans, cnidarians (anemones), tunicates, sponges, and tubeworms (Table 2-5). Larger macroinvertebrates including gorgonians, sea urchins, sea stars, and gastropods are also important components of the subtidal rocky reef habitat and have been enumerated during both site-specific and MPA surveys in the AoPE over the last 5 years.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan August 2017

Table 2-5: Percent Cover of Subtidal Rocky Reef Functional Groups and Species for Fall 2016 Surveys Conducted in the AoPE (Merkel 2016). Lechuza Point Fall Subtidal Rock Reefs 2016 Uniform Point Count (UPC) Percent Cover Functional Group or Standard Average Species Deviation Articulated Coralline 1.6 2.7 Bare Rock 5.2 2.5 Bare Sand 0.7 1.7 Brown Algae 13.9 20.8 Bryozoans 8.8 4.5 Crustose Coralline 13.5 5.7 Cup Coral 1.6 2.1 Dead Holdfast 0.0 0.0 Diatoms 0.0 0.0 Tubeworms 0.7 1.1 Gorgonian 0.0 0.0 Hydroid 0.0 0.0 Macrocystis Holdfast 0.0 0.0 Phylospadix spp. 0.0 0.0 Red Algae 6.6 6.6 Shell 0.0 0.0 Sponge 0.4 1.1 Tunicate 0.9 1.0 Flat 1.8 2.2 Moderate N/A N/A Slight 18.2 2.2 Cobble 2.0 1.4 Boulder N/A N/A Bedrock 92.4 2.2 Sand 5.7 1.7 Macroinvertebrates Number/m2 Muricea spp 2.7 2.1 (gorgonians) S. franciscanus (red 2.1 2.8 urchin) S. purpuratus (purple 4.1 3.1 urchin)

The boulder/cobble feature class within the subtidal is not well represented in spatial extent, covering just 3.57 acres of the AoPE (Table 2-1). This feature class typically occurs in association with rocky reefs or is somewhat constrained to the surf zone area of the shallow subtidal based on existing mapping (Figure 2-3. Generally, the boulder/cobbles are comprised of fractured separations of bedrock that have been eroded or alternatively cobble size material, less than 256 mm (Wentworth scale), provided from the adjacent cliffs or creek discharges. The boulder/cobble feature class within the subtidal is generally located within the energetic surf zone immediately below the Lechuza Cove intertidal area and is highly dynamic based on

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan August 2017 recent wave climates (Figure 2-3). Quantification of organisms associated with this intertidal environment is generally based on sampling ephemeral or perennial species associated with the sand environment within which the boulder/cobble feature class is interbedded (Table 2-4). In the subtidal, the boulder/cobble habitat remains highly dynamic but is more typically comprised of surfgrass, Egregia menziesii, E. arborea, various turf algae, ornate tube worm (Diopatra ornata,) Parchment tube worm (Chaetopterus variopedatus), sand tube worm (Phragmatopoma californica)and highly motile invertebrates such as decapod crustaceans (crabs/lobster) and brittle stars. No surveys or data, other than biologist observations, currently exist in the AoPE for functional groups or species occupying boulder/cobble habitat within the surf zone.

Sand bottom dominates the subtidal zone within the AoPE and the physical properties of the sand varies from fine to very coarse with the predominant sand condition being well-graded, slightly gravelly sand. Specifically, the CMECS classification of slightly gravelly sand is defined as sand containing from a trace (0.01 percent) of gravel to 5 percent gravel (particles 2 mm to <4.096 mm in diameter) with the remainder of the mixture being 90 percent or more sand (FGDC 2012). Separation of sand particles results from transient energy environments from wave and current action. This can result in sand chutes extending outward from the beach along rips as well as localized sorting from water movement around hard bottom habitats.

In general, epibenthic organisms inhabiting the sand bottom in the AoPE are relatively low in density based on observations conducted in 2013 and 2016. No quantitative surveys have been conducted, but project specific observations documented expected sand community constituents, including the ornate tube worm Parchment tube worm, and sand tube worm (; the latter two likely associated with shallow buried rock. Also, observed in low numbers were a number of mollusks, including the Channeled basket whelk (Nassarius fossatus), Purple olive snail (Olivella biplicata, and sea hare (Aplysia californica). Additional species, including the sand dollar (Dendraster excentricus), spiny sand star (Astropecten armatus), sea pansy (Renilla kolliker), and sea pen (Stylatula elongata) were uncommon but present. Finally, prominent arthropods encountered on the sand bottom include swimming crab (Portunus xantusii), elbow crab (Heterocrypta granulate), globe crab (Randallia ornata), and sheep crab (Loxorhynchus grandis).

Processing of samples collected within the shallow subtidal sands of the AoPE in fall 2016 has not yet occurred however it is anticipated that the infauna of this area will reflect a combination of both the lower beach environment with sand crabs and beach polychaetes as well as offshore benthos. The benthic community within the surf zone is expected to be more depauperate than either the beach or the offshore benthos, with increasing species richness away from the high wave disturbance zone.

The subtidal rocky reef habitat within the region supports canopy forming giant kelp (kelp) along with understory algal and faunal communities. The kelp beds within the AoPE vary considerably in scale from year to year, with persistent kelp generally lying at the west end of the AoPE, off Lechuza Point, where the greatest spatial extent of rocky reef habitat exists. Less persistent kelp is found scattered eastward of Lechuza Point on bedrock outcrops of diminishing size. For purposes of developing a general habitat map with respect to kelp canopy, a composite map was developed based on all kelp mapped from CDFW and Kelp Consortium aerial surveys to identify a maximum extent of kelp canopy potential within the AoPE (Figure 2-5). Within this composite, a few minor distribution anomalies are revealed where kelp canopy has been mapped outside of presence of any suitable substrate. It is suspected that small drift paddies were captured in the mapping efforts.

Rocky reef surveys were conducted in 2014 to assist in characterizing the subtidal environment within the AoPE (Merkel 2014). During this investigation, giant kelp holdfasts and stipes were counted. Giant kelp stipe counts during the 2014 sampling were relatively low, averaging only 11.2 ± 4.7 stipes/plant in shallow reef areas and 16.4 ± 7.5 stipes/plant in deep reefs.

Historically, the kelp canopy within the AoPE has varied considerably based on a 15-year data set developed from the CDFW and Kelp Consortium aerial surveys extending from 1989 through 2014. The data were analyzed both by determining the total acreage of mapped kelp by year within the AoPE (Figure 2-6), as well

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan August 2017 as through the development of a frequency distribution map for kelp that sums the number of times kelp has occurred at a given point divided by the number of years surveyed. The results indicate that kelp canopy within the AoPE reached a maximum peak extent in 2003 and again in 2013, with a major decline from 2004 to 2006. The maximum frequency of occurrence was 9 years out of 15 years or 60.3 percent, which only occurred on the larger reefs off of Lechuza Point (Figure 2-6).

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Figure 2-5: Frequency of Kelp Canopy Cover within the Broad Beach AoPE for 1989-2014.

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Figure 2-6: Kelp Canopy Area by Year (1989-2014) within Broad Beach AoPE Eelgrass Beds

Eelgrass (Zostera spp.), and in the case of the AoPE Zostera pacifica, occurs in the western portion of the survey area in the sandy subtidal zone in water depths generally between -25 and -43 ft NAVD88 based on June 2017 mapping efforts.

In May 2014, the distribution of eelgrass in the AoPE covered 7.1 acres with an average density of 72 turions/m2 (Merkel 2014). Eelgrass beds revealed a well-developed distribution of plants that were not fully coalesced to the extent of having undefined boundaries between individual plants. The distribution of eelgrass appeared related to the presence of the reef protection afforded to sand flats on the Photo 2-1: Well developed distribution of eelgrass plants in the AoPE documented in spring 2017. leeward side of Lechuza Point, and more specifically the offshore bedrock reefs.

Surveys conducted in June 2016 documented only 0.85 acres of eelgrass in the AoPE, nearly an order of magnitude decrease in spatial extent from the 2014 survey. A density of 57.6 turions/m2 was documented in 2016 revealing a reduction of eelgrass density compared to the 2014 survey data. The spatial extent of eelgrass in the AoPE rebounded to 1.6 acres in 2017, but still remains significantly lower than the 2014 area (Figure 2-7). Surveys conducted in June 2017 documented an average density of 35.3 turions/m2 in the AoPE, providing evidence of a continued reduction in density, most likely Photo 2-2: Disperse eelgrass community commonly related to the variability in the overall eelgrass cover observed in the AoPE and reference sites in 2017. observed as the eelgrass communities recover from the 2015 winter storm impacts.

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In 2016 visual observations of eelgrass beds in the AoPE documented highly impacted beds with damage appearing to be related to physical impacts of wave movement of sand within the bed area. Given the relative depth distribution of the beds down to approximately 43 ft NAVD88, and signs of sand channel scour at the nearby reefs extending below 50 ft NAVD88, eelgrass communities within the AoPE appear to be influenced by substantial water movement resulting from large winter wave events. Eelgrass beds in the AoPE in 2017 appeared healthy but spatially disperse and rarely observed as a continuous bed covering greater than 25-50 percent cover in any one area.

Epiphytic loading on the eelgrass was low during all the surveys, although some spirobids were present along with a number of epiphytic and plant grazers, such as Lacuna sp. snails and Idotea, observed on the leaves. The eelgrass present in the AoPE was documented to host a number of invertebrates including sheep crab, slender crab (Cancer gracilis), sea hare, ornate tube worms, and sand stars. Multiple gastropods also occur on the eelgrass leaves. Fish that were commonly observed in the eelgrass beds include round ray (Urobatis halleri), senorita (Oxyjulis californica), and speckled sanddab (Citharichthys stigmaeus). Many other species were not observed within the eelgrass, but are known to use this habitat.

In summary, the existing conditions of marine habitats within the AoPE are defined by elevation, substrate type, and biotic communities, with some individual biotic communities warranting their own feature class (eelgrass and kelp canopy). The temporal and spatial changes of the marine habitat and feature class extent are subject to seasonal and annual fluctuations that most certainly track regionally within the littoral cell that extends from Point Dume to Point Mugu. Thus, it is expected that future and historical natural changes to the AoPE, with respect to spatial extent of tidal elevations, will be relatively small and second order shifts in substrate: bedrock, unconsolidated mineral substrates of boulder/cobble, and sand proportional to regional trends under natural conditions. The status and condition of the biotic communities and their components (functional groups and species) are documented in this section from site-specific survey data collected as part of pilot studies or from regional monitoring programs conducted within the AoPE as part of the MPA process. Overall, the spatial extent of feature classes within the AoPE have been mapped multiple times since 2013 and provides a factual range of the variance of feature class distribution. Additionally, biotic communities and components associated with the various habitats and feature classes have, for the most part, been suitably evaluated through Project-specific surveys or as part of MPA monitoring that sets an applicable basis for the pre-Project condition.

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Figure 2-7: Eelgrass within Broad Beach AoPE - 2014, 2016 & 2017

REGIONAL AND HISTORIC SAMPLING PROGRAMS A variety of historical data exists for various marine habitats and biotic features in the region surrounding the AoPE. These include data from sampling of sandy beach, rocky intertidal, rocky subtidal, and kelp canopy. Eelgrass and kelp canopy monitoring or survey efforts for which data are available principally include agency sponsored programs that present the status of resources in a regional context. Historical data for sandy beach, rocky intertidal, and rocky subtidal habitats have been collected for site specific areas, including the AoPE, by programs such as PISCO, Multi-Agency Rocky Intertidal Network (MARINe), State Water Resources Control Board (SWRCB) ASBS, and South Coast MPA Baseline monitoring throughout the region (Figure 2-8Figure 2-8 through Figure 2-13). The goals for the various surveys differ and do not necessarily serve the specific needs of monitoring sand related impacts potentially elicited by this Project; however, they do assist in characterizing the region in a manner of identifying and evaluating reference sites and development of monitoring methods. Figure 2-8 through Figure 2-12 depict the historical distribution of eelgrass and kelp canopy in the region developed from mapping data compiled from comprehensive eelgrass baseline surveys and kelp canopy monitoring programs. The area evaluated for existing regional information was an approximately 22-mile-long stretch of shoreline extending approximately 10 miles north of the westerly end of the AoPE and 10 miles east of the extended beach monitoring area on Zuma Beach (Figure 2-2). In practice, the evaluated shoreline reach extended along the shoreline from Mugu Lagoon to Malibu Lagoon, including the prominent Point Dume headland. The shoreline area within the region investigated ranges from predominantly south facing at the west end of the region to southwest facing on the west side of

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Point Dume, to southeast facing on the east side of the point, and back to south facing within Santa Monica Bay near Malibu Lagoon. As discussed previously, on a smaller scale, the shoreline is defined by headlands, shallow cove formations, and trailing beaches with the prominent exception of the long Zuma Beach built against the upcoast side of Point Dume.

The following section briefly describes the goals, objectives, methods, and findings from regional and Project specific surveys conducted in the AoPE and at potential reference sites in the vicinity of the AoPE. Also, given the amount of data available in these studies, only the findings applicable to or those that assisted in development of this Plan are presented.

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Figure 2-8: Eelgrass Monitoring West of Broad Beach, Merkel & Associates, 2015

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Figure 2-9: Kelp Canopy West of Broad Beach, MBC Applied Environmental Sciences, 2015

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Figure 2-10: Historical and Ongoing Monitoring Locations Under Various Programs West of Broad Beach.

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Figure 2-11: Eelgrass Monitoring East of Broad Beach, Merkel & Associates, 2015

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Figure 2-12: Kelp Canopy East of Broad Beach, MBC Applied Environmental Sciences, 2015

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Figure 2-13: Historical and Ongoing Monitoring Locations Under Various Programs East of Broad Beach.

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Regional and Historic Data Supratidal Zone No targeted sampling of the supratidal littoral zone has been conducted in the AoPE or vicinity. However, some of the historic intertidal monitoring includes these areas as the upper most elements within the monitored locations. For rocky intertidal habitat, the sampled area generally includes the splash zone, with some sampling in the spray zone above intertidal. For the beach monitoring program, sampling has included high beach or dry sand sampling and wrack sampling, with wrack distribution being strongly influenced by wave run up on the beaches. Following the monitoring program framework, sampling in the supratidal zone will be most appropriately evaluated through the Dune monitoring program and the supratidal margins are addressed under the intertidal monitoring discussion below.

Photo 2-3: Slightly gravelly sand beach – May 2016 (top). Note the low gradient and concentrated flow (right side of top photo) as water runs out of a shore parallel swale between a nearshore beach rise and the rise of the upper beach. This flat beach profile has been observed even when sand is stacked against the base of the revetment – February 2016 (bottom).

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Intertidal Zone Rocky Intertidal

Six rocky intertidal sites in the vicinity of Broad Beach have been sampled during the MPA monitoring process, or as part of a collective effort to monitor long-term trends of this habitat along the Pacific Coast, under the MARINe program (Figure 2-10 and Figure 2-13; Table 2-6). Two general approaches/levels of effort have been applied to the sampling and include long-term monitoring and Biodiversity surveys. Long-term monitoring sites have typically been established in areas where the coastline consists of contiguous rocky reef. These rocky reefs are usually quite broad (width between 30-50 m) and long (length between 50-500 m). Contiguous rocky reefs are the most stable of rocky intertidal habitats, and targeting a specific habitat type results in higher consistency among sites. This allows for better comparisons among sites and regions as well as long-term detection of trends. This basic level of consistency in site selection remains important because targeted reefs vary immensely by rock type, shape, rugosity, exposure, surrounding habitat, human visitation levels and other factors, which all contribute to explaining patterns in long-term community dynamics. Biodiversity survey sites are located in the same areas as long-term sites, or in areas of special interest (e.g. ASBS). Sites are typically established in areas where at least 30 m of contiguous rocky reef (the length of the baseline transect) exists, but a site can be broken into two or more smaller sections or adapted as necessary to fit within the constraints of Photo 2-4: Boulder/cobble field in partially sanded condition – smaller rocky reefs. February 2016 (top); generally scoured condition with ephemeral algal communities – May 2016 (middle); and surfgrass bed in sanded environment – February 2016 (bottom).

Table 2-6: Physical Attributes and Survey Approach for Rocky Intertidal Sites in the Vicinity of Broad Beach from Northwest to Southeast Primary Bench Surrounding Survey Site Slope Relief Extent Orient. Type Coast Type Old bedrock/boulders/ LT, moderate moderate long boulders/sand SW Stairs sand BD Deer bedrock/boulders/ bedrock/sand gentle moderate short SE BD Creek sand Sequit bedrock/boulders/ LT, bedrock gentle moderate long S Point sand BD Lechuza LT, bedrock/sand moderate moderate long bedrock/sand S Point BD Point bedrock/boulders/ bedrock/boulders/ gentle moderate intermediate S BD Dume sand sand Paradise LT, bedrock/sand moderate low intermediate sand SE Cove BD Notes: S – south; SE – southeast; SW – southwest; LT – long term; BD - Biodiversity

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Since rocky intertidal areas tend to be dominated by several key species, the long-term approach, developed by a consortium of organizations collectively called MARINe, targets prominent functional groups and key species with the idea that changes in functional groups and key species track changes of less abundant or conspicuous species in the community. This targeted approach provides the ability to: a) detect relatively small changes in the abundance of species; and can b) utilize large groups of supervised, less experienced personnel to complete the investigations. The information about the dynamics and diversity of rocky intertidal habitats allows for detection of natural and anthropogenic trends or impacts that extend over time and which influence the monitored locations. Under this type of monitoring program, focal species are monitored within fixed plots and transects on an annual or semi-annual basis.

The collective monitoring program includes goals of documenting species richness and changes in the distribution of species within and among sites over time. To accomplish these goals, complementary biodiversity surveys have been implemented to capture information about the rocky intertidal community as a whole, rather than focal species, with the goals being to: 1) determine the diversity and site-wide abundance of intertidal algae and invertebrate species; 2) create a topographic map for use in assessing the spatial distribution of species within each site; 3) reveal long-term influences such as climate change and coastal development on intertidal communities and individual species; and 4) examine patterns of biogeography with a particular emphasis on locations where there may be large changes in species composition and diversity.

In comparison to different components of the monitoring program described above, biodiversity surveys are far more intensive and require a high-level of expertise and consistency in the identification of marine organisms, and are thus done on a less frequent schedule, typically every 3-5 years. When considered together, the two intertidal monitoring frameworks provide both a functional understanding of the structure and the dynamics of the sampled rocky intertidal habitats. The results of these investigations are briefly outlined below by sampling area. In combination, the long-term, targeted species approach and the biodiversity surveys provide a wealth of information about the structure and dynamics of rocky intertidal communities along the Pacific Coast (SCCWRP 2012a, SCCWRP 2012b, et al. 2015).

Taking into consideration the proximity, physical features, and aspect (shoreline exposure) of the various monitoring sites, that provide suitable data for consideration as reference sites relative to the AoPE, historical data are presented for the sites nearest and most similar to the AoPE.

Detailed summary information from monitoring conducted at each of the six rocky intertidal sites is available through the internet links embedded in this document. Information provided in these site summaries is derived from data publicly available. Original authorship of information is not always clear from the website presentation; therefore, it is not possible to fully credit information beyond the monitoring program and website reference.

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Old Stairs

Old Stairs is the northern most site considered to be a reference location and lies in Mugu Lagoon to Latigo Point ASBS. This moderately sloping site consists of extremely uneven terrain, containing many deep cracks and folds. Old Stairs is dominated by a mixture of consolidated sandstone bedrock, riprap, boulder fields, and sandy beach. The area surrounding the site is comprised of a mixture of boulder fields and sandy beach. The primary coastal orientation of this site is southwest. The site has been monitored as a long-term survey site established in 1994; MARINe surveys conducted on the site presently include the following target species: Anthopleura spp (anemones), Chthamalus/Balanus (barnacles), Mytilus californianus (mussels), Endocladia muricata, and Pisaster spp. Rock above the barnacle zone was added in 2008 in order to track the influences of anticipated sea level rise. In addition to target species, motile invertebrates, barnacle recruitment, and mussel size structure are monitored at this site. Photo 2-5: The Old Stairs site is a southwesterly oriented low Monitoring at Old Stairs has revealed fairly substantial bench bedrock intertidal site surrounded by sand beach that intermittently has greater or lesser extents of sanded variations in organisms cover over time. In the case of boulder/cobble environment (top, UCSC photo). The site is anemone plots, high variability due to sand inundation was an overall small rocky protrusion of bedrock ridges backed by observed from 1994 through 2002, and more subsequent a revetment slope along Highway 1 and small beach features (bottom, Google Earth 2013). gradual change, with cover ultimately declining from 70 percent to around 40 percent cover by 2012. The barnacle plots declined from nearly 100 percent cover in 1994 to less than 20 percent cover in 2010, with rebounds and declines leading to an approximate 25 percent cover as of fall 2014. For broader consistency comparisons with Biodiversity surveys conducted in 2009 and 2013, the percent cover of key species in long term monitoring plots for those years was: anemones (8.2 and 13.1), barnacles (12.9 and 13.3), Endocladia muricata (7.3 and 12.2), and mussels (11.9 and 15.7), respectively. Following 2010, plots have become dominated by Endocladia muricata and mussels along with bare rock. The mussel plots exhibited major declines in mussel cover from around 80 percent in spring 1995 to near 30 percent the following fall, followed by a corresponding increase in barnacle cover and bare rock. Mussels have gradually recovered with more minor declines and recoveries defining the trend.

Long-term monitoring program details may be found at: http://www.eeb.ucsc.edu/pacificrockyintertidal/sitepages/oldstairs-lt.html.

Results from Biodiversity Surveys conducted in 2001 and 2008 can be obtained at: http://www.eeb.ucsc.edu/pacificrockyintertidal/sitepages/oldstairs-lt.html.

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Deer Creek

Deer Creek is located in Mugu Lagoon to Latigo Point ASBS. This gently sloping site is greatly sand influenced with a steep drop-off into a channel, and consists of moderately uneven terrain, containing few cracks and folds. Deer Creek is dominated by a mixture of consolidated basalt and sandy beach. The area surrounding the site is comprised of a mixture of consolidated bedrock, boulder fields, and sandy beach. The primary coastal orientation of this site is southeasterly, being partially protected from the west by being tucked into the curvature of the coastline into a small beach. The site is backed by revetment along Highway 1. Biodiversity Surveys within this area were performed in 2013. The highest percent cover at this site included Chthamalus dalli/fissus, Mytilus californianus, and polychaete worms. Bare rock was the dominant overall cover at greater than 31 percent of the site, with sand occurring on nearly 15 percent of the Photo 2-6: The Deer Creek site is a southeasterly oriented site. flat topped bedrock bench intertidal site (top, UCSC photo) surrounded by sand beach and sandy subtidal environments with some additional rock outcrops in the offshore shallows. This site has also been regularly surveyed as a The site is an overall small rocky protrusion of bedrock ridges LiMPETS (Long-term Monitoring Program and backed by a revetment slope along Highway 1 and small Experimental Training for Students) site since 2006. beach features. The actual sampled site is one of a number of small parallel outcrop exposures of a similar nature located This is an environmental monitoring and education in this area (bottom, Google Earth 2013). program.

Other biodiversity monitoring information can be obtained on the monitoring program website at: http://www.eeb.ucsc.edu/pacificrockyintertidal/sitepages/deercreek.html.

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Sequit Point

Sequit Point is located in the Mugu Lagoon to Latigo Point ASBS. This rocky headlands site is comprised of moderately uneven terrain, containing few cracks and folds. The site is one of two primary headland points extending seaward north of Leo Carrillo State Park and dominated by consolidated bedrock. The area surrounding the site is comprised of a mixture of consolidated bedrock, boulder fields, and sandy beach. The primary coastal orientation of this site is south. The headlands occur to the north of Arroyo Sequit Creek, which has an approximately 6,000-acre watershed. The characteristics of this site are generally similar to those of Lechuza Point in scale, relief, orientation, and substrate, as well as overall site context and composition. Biodiversity surveys were performed in 2009 and 2013, although 2013 data are not available online. Within the Sequit Point Biodiversity monitoring conducted in 2009, the dominant fauna consisted of barnacles (Chthamalus dalli/fissus) and mussels (Mytilus californianus), both comprising between 18 and 14 percent of the total cover, respectively. All other organisms occurred at densities of less than 5 percent total cover, with the dominants in this range of cover being Balanus glandula, polychaetes worms, and Photo 2-7: The Sequit Point site is a southerly oriented bedrock bench surrounded by sand, boulder/cobble, and other Corallina spp. Rock dominated the substrate with bedrock features (top, UCSC photo). The site is the westerly almost 50 percent of the points during point contact of two prominent points extending seaward within Leo surveys supporting bare rock. Conversely, less than 3 Carrillo State Beach (bottom, Google Earth 2013). percent of the contacts occurred in sand. The remainder of the contacts were on algal or invertebrate cover. Limpets and littorine snails dominated the biota in biodiversity quadrats, revealing the relatively high elevation of the sampled rock. During the monitoring conducted at this site, surfgrass was not encountered.

Other Biodiversity Survey information can be obtained at the monitoring program webpage: http://www.eeb.ucsc.edu/pacificrockyintertidal/sitepages/sequitpoint.html.

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Lechuza Point Lechuza Point is located within the Point Dume SMCA, and is located in Mugu Lagoon to Latigo Point ASBS. This moderately sloping site consists of moderately uneven terrain, containing few cracks and folds on the sampled headland. Lechuza Point is dominated by a mix of bedrock and sandy beach that is intermittently exposed to reveal boulder/cobble substrate. The site has a predominantly southerly exposure orientation and ramps to the south to lower elevations.

Biodiversity surveys were completed in 2009 and 2013, although 2013 data are not yet available online (as of July 2017). During the 2009 Biodiversity point contact surveys, the dominant organism sampled was Mytilus californianus at over 16 percent cover. Other higher cover species included Chthamalus dalli/fissus and polychaetes worms, both exceeding 5 percent cover. The sampling at this site also detected surfgrass at less than 1 percent of the total cover. Lechuza Point Photo 2-8: The Lechuza Point site is a southerly oriented bedrock bench surrounded by sand, boulder/cobble, and other sampling supported a surprising sand cover in excess of bedrock features (top, UCSC photo). The site is within the 22 percent with a bare rock cover falling just below 8 west end of the AoPE and is a primary area of concern in this percent. This high degree of sand on the prominent monitoring program. The site sampled during long-term monitoring program activities is the dominant rocky headland headland was somewhat of a surprise as this area is feature located to the west of smaller and lower rocks that dot generally fairly clean. The elements that may assist in the westerly portion of Lechuza Cove and which create a explaining this high proportion of sand are that the mosaic of bedrock reef and active sand channels that are believed to convey sand into and out of Lechuza Cove sampled area of Lechuza Point supports a number of (bottom, Google Earth 2013). non-draining tidepools that would be expected to trap suspended sand. In addition, any transect that extends over the rock edge would be expected to hit either sand or boulder/cobble at the base of the headland.

Biodiversity density data collected in 2009 and 2013 revealed considerable overall differences in species representation, with most species exhibiting relatively stable dominance positions through time, even though the overall densities differed from survey to survey. In general, organism densities were higher in 2009 than in 2013. The presence of a broad range of organisms represented suggest either a broader elevation range of sampling at Lechuza Point than Sequit Point, or sampling that included tidepool components in addition to upper intertidal rock.

Other Biodiversity survey information can be obtained at the monitoring program webpage: http://www.eeb.ucsc.edu/pacificrockyintertidal/sitepages/lechuzapoint.html.

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Point Dume

Point Dume is located within the Point Dume State Marine Reserve (SMR), and in the Mugu Lagoon to Latigo Point ASBS. This reef is distinct from the other rocky intertidal monitoring areas in the investigated region in that it supports more extensive basalt rock, has higher wave exposure, and generally lacks abundant small boulder/cobble substrate than other sites. This reef has steep drop offs from the reef edge onto sand and bedrock subtidal. Between small fingers of the reef, small surge channels extend towards the steep rock of the point and generate very small low intertidal pocket beaches. The sampled area of reef included some scoured platform areas as well as megaclasts that have fallen from the eroding point into the intertidal. The monitoring program describes the study area consisting of moderately uneven terrain, containing few cracks and folds. However, the overall intertidal environment at Point Dume is quite complex.

The primary coastal orientation of this site is south. Photo 2-9: The Point Dume site is a southerly oriented bedrock exposure also comprised of megaclast bedrock that This site is considered to be the most exposed of the has fallen from the eroding point to the intertidal. Intermixed sites in the region that have been examined through the with the rock is large boulder rubble and transient sand (top, biodiversity surveys. This monitoring location is quite UCSC photo). The site is located at the tip of Point Dume with the bedrock feature continuing offshore to support a different from the smaller headland features represented headland kelp bed (bottom, Google Earth 2013). at Lechuza Point and some of the other monitoring sites. Biodiversity surveys were conducted at this location in 2013; however, no data are yet available online (as of July 2017).

Other Biodiversity survey information can be obtained at the monitoring program webpage: http://www.eeb.ucsc.edu/pacificrockyintertidal/sitepages/pointdume.html.

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Paradise Cove

Paradise Cove is also located in the Mugu Lagoon to Latigo Point ASBS and within the Point Dume SMCA. This site consists of an uplifted sandstone bedrock terrace sloping at a relatively consistent planar angle into a sand beach environment that is persistent, but variable in scale with intermittent exposure and burial of reef platforms within the cove. The site has been described as having moderately uneven terrain, containing few cracks and folds. The primary coastal orientation of this site is southeast. The site is well protected from northerly and westerly waves by Point Dume. This site has a very different geology, rock topology, and energy environment than any of the other intertidal sites that have been part of regional monitoring programs.

Long-term monitoring surveys at Paradise Cove were established in 1994, and MARINe surveys currently Photo 2-10: The Paradise Cove site is a southeasterly target the following species: Chthamalus and Balanus oriented sandstone bedrock uplift terrace (top, UCSC photo). The site is located within Paradise Cove and is protected from (barnacles), Mytilus californianus (mussels), all but southerly storms by the prominent Point Dume to the Endocladia muricata, Phyllospadix spp, and Pisaster west. The intertidal rock is part of a continuous reef complex spp. In addition, motile invertebrates, barnacle of exposed ridges interspersed with sand bottom habitat (bottom, Google Earth 2013). recruitment, and mussel size structure are monitored at this site. Plots exhibited high overall variability with respect to target species cover. Within Endocladia plots, Endocladia, barnacles, mussels and rock have all dominated at various times through the monitoring program. Endocladia has ranged from a low mean cover of approximately 20 percent in 1994 and nearly zero cover in the fall of 2015. However, in the intervening years, cover rose to around 60 percent prior to a crash in 2004. Conversely, barnacles had been over 40 percent of the cover in 1994, but declined substantially by 1996 and have never returned. Mussel cover was negligible for the first nine years of sampling, but began increasing in 2003, reaching 60 percent cover by 2006. Subsequently, the mussel cover has declined to almost 20 percent and been replaced by bare rock.

The cover of surfgrass has fluctuated throughout the years with seasonal variation (lower in spring, higher in fall) along with intermittent periods of basal sand burial. Cover of Phyllospadix spp. has hovered around 60 percent with one substantial population decline in 1997-1998. This period was marked by an increase in sand followed by a sharp increase in rock during spring 1998, suggestive of loss due to sand burial and/or scour followed by sand removal and subsequent bed recovery. The observations of increased sand presence at Paradise Cove are potentially analogous to the observations of increased sand within Lechuza Cove during winter periods (rather than summer when other beach environments are typically building). It is potentially the case that stormy periods (e.g. winter, and particularly El Niño periods) drive mobilized sand to quiescent areas such as Paradise Cove and Lechuza Cove.

Results from biodiversity surveys conducted in 2001, 2006, and 2010 and long-term monitoring are available at http://www.eeb.ucsc.edu/pacificrockyintertidal/sitepages/paradisecove-bio.html.

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Community Similarity Across Rocky Intertidal Sites

Using the collected intertidal monitoring data from the Biodiversity surveys for the South Coast Baseline Program, biogeographic patterns in intertidal community structure were analyzed by Blanchette et al. (2015) for the sessile and mobile biodiversity assemblage data using similarity profile analyses (SIMPROF) test to determine significant relationships between community groups across multiple monitored sites. For sessile taxa, 14 significant community groups were identified for all sites examined within the South Coast Study Region, with two of the sites (Mussel Shoals and Muddy Canyon) occurring as outliers that did not group with any other site. Community or functional groups are determined for sessile invertebrates or alga based on their intertidal elevation, genus, or physical form. For example, both Cthamalus dalli and Cthamalus fissus are barnacles occupying primarily the high splash zone leading to the functional group barnacles. In contrast, both Pollicipes polymerus (gooseneck barnacle) and Tetraclita rubescens (pink acorn barnacle) occupy different tidal elevations, thus are not functionally grouped with the other barnacles. Red algae are diverse and abundant lending them to grouping as well (e.g. red algae). Similar functional groups like limpets, anemones, and crustose corallines follow the same logic. For sites in the vicinity of Broad Beach, Old Stairs, Sequit Point, Deer Creek, and Point Dume displayed similarities in species diversity and density more closely together than Lechuza Point or Paradise Cove, which were very different from each other. Notably, Lechuza Point clustered more closely with a number of outer Channel Island sites and Point Conception.

Long term monitoring conducted by both MARINe and Biodiversity surveys provides excellent site-specific data and methods for consideration in the sampling of intertidal functional groups and species. While the similarities between sites varies based on several factors, the application of the surveys sampling methodologies and long-term trend data are extremely valuable in developing and evaluating changes to intertidal biotic communities. A comparison of the Lechuza Point, within the AoPE, and Sequit Point display a high degree of similarity with respect to noted (bold) functional groups (Table 2-7). For mobile taxa, nine significant community groups were identified, with sites in the vicinity of Broad Beach, all sites clustered relatively close to one another. For multiple reasons, the Biodiversity survey methods will be used as a basis to construct the intertidal monitoring framework and the inclusion of the existing survey sites weighed heavily in selection as applicable reference sites.

Table 2-7: Intertidal Biodiversity UPC (percent cover) of Functional Groups and Species for Lechuza Point (AoPE) and Sequit Point for the years of 2009 and 2013)

Lechuza Point Sequit Point

Functional Group/Species Fall Fall Fall Fall 2009 2013 2009 2013

Anemone 4.1 6.3 4.4 0.9 Articulated Coraline 2.5 6.2 0.0 0.0 Barnacles 10.0 10.7 23.4 17.9 Blue Green Algae 0.0 0.2 1.5 Brown Algae 0.6 0.5 0.3 0.0 Crabs 0.0 0.0 0.0 0.2 Deep Pool 0.0 12.3 0.0 0.3 Diatoms 0.1 0.0 0.0 1.0 Egregia menziesii 14.9 6.3 3.7 0.9 Endocladia muricata 1.3 0.1 0.0 0.0 Encrusting Coraline 0.1 1.5 2.0 3.4 Green Algae 0.0 0.0 0.1 0.0 Limpets 0.5 0.7 4.8 0.6 Littornia spp. 2.2 0.1 0.0 0.1 Megabalanus spp. 0.0 0.1 0.0 0.0 Mussels 0.0 0.0 0.1 0.1

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Lechuza Point Sequit Point

Functional Group/Species Fall Fall Fall Fall 2009 2013 2009 2013

Mytilus californianus 16.5 12.4 13.4 15.0 Nautillna spp. 0.1 0.0 0.1 0.0 Other Substrate 0.0 0.2 0.0 0.0 Phragmatopoma 6.1 8.8 4.1 3.6 californica Pisaster spp. 0.5 0.3 0.2 0.3 Pollicipes polymerus 0.9 1.2 1.1 0.9 Red Algae 6.9 9.2 2.3 2.8 Rock 7.9 17.6 39.1 47.5 Sand 22.3 3.8 0.0 2.3 Septifer 0.2 0.3 0.0 0.0 Sponge 0.0 0.1 0.0 0.0 Surfgrass 0.6 0.6 0.0 0.0 Tar 0.0 0.1 0.0 0.0 Tegula spp. 0.2 0.0 0.0 0.4 Tetraclita rubecens 0.5 0.3 0.4 0.3 Ulva spp. 1.1 0.3 0.2 0.0 Worm 0 0.3 0.0 0.1

Sand Beach

Two beaches in the vicinity of Broad Beach were sampled as part of the South Coast MPA Baseline Program, Leo Carrillo and Dume Cove (Figure 2-10 and Figure 2-13). This study provides a baseline assessment of the ecological state of sandy beach ecosystems in association with designation of MPAs in California’s South Coast MPA region. Within the beach sampling program, three different survey and sampling approaches were employed, including rapid surveys, Biodiversity sampling, and target sampling. These were used to describe biotic and physical characteristics of the beach and surf zone. In total, 12 sandy beaches in the Southern California region were sampled. These are described in Dugan et al. 2015 (http://oceanspaces.org/projects/south-coast-baseline- characterization-sandy-beach-ecosystems).

Rapid surveys were used to describe the distribution, abundance and seasonal occurrence of shorebirds, people and fresh kelp wrack. Investigators conducted monthly daytime surveys during low tides on standard alongshore transects at 12 focal beaches. A number of physical Photo 2-11: Slightly gravelly sand beach – May 2016 (top). characteristics were measured for each beach segment Note the low gradient and concentrated flow (right side of top photo) as water runs out of a shore parallel swale surveyed including beach zone widths and slopes, between a nearshore beach rise and the rise of the upper macrophyte wrack cover, wave regime, and sediment beach. This flat beach profile has been observed even when grain size on cross shore transects that were established in sand is stacked against the base of the revetment – February 2016 (bottom). a representative sandy area. The extent and presence of

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan each type of wrack was recorded on each of three shore normal transects of variable length that extended from the lower edge of terrestrial vegetation or the bluff or dune to the lowest intertidal level exposed by swash at each location.

Biodiversity sampling was conducted on three shore-normal transects extending from the lower edge of terrestrial vegetation or the bluff to the lowest level exposed in the swash zone at low tide. Vertical transects were divided into 15 uniformly spaced levels to facilitate sample processing and allow future analyses of intertidal zonation (should that ever be performed). For the present program, tidal elevations were not considered and analyses were performed on pooled samples for the entire beach profile. Ten evenly spaced cores were collected on each of the 15 levels and cores were pooled. Each sample consisted of a cylindrical core (0.0078 m2, 100 mm diameter) collected to a depth of 200 mm. The cores were sieved through a 1.5 mm mesh and retained samples were preserved for subsequent sorting, taxonomy, enumeration, and wet weight biomass determination.

In addition to biodiversity sampling, focused sampling of indicator taxa consisting of Emerita analoga (Pacific mole crab) and wrack-associated Megalorchestia spp (talitrid amphipods) was performed. The abundance, biomass, and population characteristics of indicator taxa were estimated using sampling protocols that were generally similar to those used in the intertidal biodiversity sampling. However, the sampling also exhibited some variation in the sampling layout, depth and number of cores collected in order to target indicators.

The study found species richness of intertidal macroinvertebrates varied more than threefold among study beaches, ranging from 12 to 45 species across sites (Figure 2-14). A total of over 83 different macroinvertebrate taxa were observed in the Biodiversity surveys across all the study beaches, with 37 species and 29 species observed at Leo Carrillo and Dume Cove, respectively (Dugan et al. 2015). Macroinvertebrate abundance and biomass varied considerably among the study beaches as well. In addition, macroinvertebrate abundance and biomass were not correlated with each other. Total abundance varied over an order of magnitude from a minimum of 8,575 individuals/m of shore normal beach length at San Clemente Beach to a peak of 134,649 individuals/m of beach length at East Campus Beach. Both Leo Carrillo and Dume Cove were on the lower end with abundance less than 50,000 individuals/m of beach length. Total mean biomass of macroinvertebrates varied nearly sixfold among the study beaches ranging from 1,450 g/m at Carlsbad Beach to 8,685 g/m at Leo Carrillo Beach. Values of wet biomass exceeded 5,000 g at four of the study beaches and included both Leo Carrillo and Dume Cove. At Leo Carrillo and Dume Cove, this high biomass was primarily due to high abundance of Emerita analoga (Dugan et al. 2015).

The MPA Baseline Program also conducted four surveys of potential macroinvertebrate indicator taxa, Emerita and Megalorchestia spp. in spring (May/June) and fall (September/October) of 2012 and 2013. Spatial patterns in abundance and biomass of the two indicator taxa in fall surveys were generally similar to those observed in biodiversity sampled only in fall 2011. However, extreme variability was observed between spring and fall abundance of the indicator taxa at many of the study beaches. This was particularly evident for sand crabs, Emerita analoga, where populations varied by many orders of magnitude, driven by strong spring recruitment and declines to much lower levels by fall (Dugan et al. 2015).

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Figure 2-14: Species Richness, Abundance, and Biomass of Beach Macroinvertebrates within MPA Baseline Study Beaches in Fall 2011 (from Dugan et al. 2015). The average abundance of Emerita analoga varied over an order of magnitude among the study beaches, ranging from 4,074 to 115,365 individuals/m in the spring surveys and 484 to 26,021 individuals/m in the fall surveys. Both Leo Carrillo and Dume Cove stood out in terms of exhibiting high biomass of E. analoga in fall surveys. Average abundance was generally higher in spring than fall, reflecting the strong influence of the spring recruitment period on population abundance. The abundance of E. analoga in the fall survey was not correlated with that of the preceding spring survey, suggesting survival varies substantially over the post- recruitment period (Dugan et al. 2015).

The mean biomass of E. analoga varied by over three orders of magnitude among the beaches, ranging from 0.42 g/m to 17,553 g/m in spring and 48.8 to 6,804 g/m in fall across the sampled beaches. Mean biomass was lower in fall surveys than spring surveys at a majority of the beaches. Biomass of E. analoga in the fall 2013 survey was significantly correlated with that of the preceding spring survey in 2013, but this was not the case in 2012 (Dugan et al. 2015). Mean biomass values exceeded 5,000 g/m at Leo Carrillo in spring and fall of 2012.

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For talitrid amphipods, mean abundance varied by of over two orders of magnitude among study beaches. Highest abundance occurred on beaches with high wrack abundance. Generally, Leo Carrillo and Dume Cove displayed relatively low abundance. Strong seasonal variation in abundance was evident at several sites, but no consistent pattern in overall mean abundance was apparent between spring and fall surveys (Dugan et al. 2015). Similarly, mean biomass also varied by over two orders of magnitude among beaches ranging from 4 to 811 g/m in spring and 3 to 1,246 g/m in fall surveys, with both Leo Carrillo and Dume Cove performing in the lowest half of sites for both abundance and biomass.

The data and conclusions from the prior MPA baseline sampling suggest high overall dynamism among beach sites, and no specific inter-site, inter-seasonal, or inter- annual trends. However, when reviewing the data most closely, species richness appears to be the most stable metric across sampled sites with no particularly strong patterns emerging among richness and abundance or biomass (Figure 2-14, Figure 2-10). However, the study found significant negative correlations with increasing sediment grain size within the sampled beach as well as negative correlation between species richness and beach slope, a coincident variable with increasing grain size. The study did not attempt to distinguish slope effects from grain size effects. The study also concluded that the indicator taxon of E. analoga does not respond well to differences in beach morphodyamics and that wrack accumulation constitutes an important factor in driving richness and abundance of macroinvertebrate fauna on sampled beaches.

Subtidal Zone Photo 2-12: Bedrock reef within the AoPE varies from low relief reef, typically found nearshore (top) to isolated rock Rocky Reef outcrops, generally more common further to the east of Lechuza Point (middle) to larger rocky outcrops with more Similar to the rocky intertidal monitoring programs, complex topographic relief generally most common at the west end of the AoPE off Lechuza Point (bottom). quantitative large-scale spatial and temporal studies on subtidal rocky reef habitat have been developed, including the Channel Islands National Park Service’s Kelp Forest Monitoring Program, PISCO, and MPA monitoring conducted by the Vantuna Research Group at Occidental College, and, more recently, Reef Check California (RCCA).

In 2003-2004, the CDFW supported the Cooperative Research Assessment of Nearshore Ecosystems (CRANE) that sampled 88 reefs with a standardized protocol from Santa Cruz to the Mexico Border including the southern California islands (https://www.wildlife.ca.gov/Conservation/Marine/FIR/CRANE).

In 2011-2012, the South Coast Baseline Kelp and Shallow Rock Ecosystems Programs' goal was to describe the ecological conditions of kelp and shallow rock ecosystems inside and outside of MPAs in the South Coast Study Region (SCSR) and to integrate these baseline surveys together with historical data to illustrate changes in conditions over both short and longer time scales.

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The monitoring approach applied in the subtidal reef environment has been based primarily on SCUBA diver surveys quantifying the density and abundance of the macroalgae, invertebrates and fishes that constitute reef communities. This approach characterizes and quantifies ecosystem attributes such as biodiversity, community structure, population abundance and size structure of ecologically and economically important species.

A site is defined as a contiguous rocky-reef habitat along a portion of the coast greater than 500 m in length. Within that section of coast, surveys are conducted across a depth range from 5 m to 20 m, or to the deepest extent of the reef if it is less than 20 m deep. Most of the areas monitored support forests of giant kelp, Macrocystis pyrifera, or bull kelp, Nereocystis leutkeana, to the north.

Each site is divided into two survey areas located approximately 500 m apart within the same reef complex. Within each area, sampling is stratified across zones defined either by depth (shallow to deep) or proximity to shore (onshore to offshore edges of the reef). The basic unit of sampling is a transect randomly located within each of the stratified zones in each area. The sampling approach is based on protocols developed for long-term monitoring by PISCO, and four types of diver surveys are used to characterize the rocky reef and kelp forest ecosystem:

1. fish density and size distribution are recorded along belt transects on the reef surface, mid-portion of the water column, and top-portion of the water column when kelp canopy is present;

2. density of large (>2.5 cm) invertebrates and stipitate algae are recorded along “swath” transects on the reef (Table 2-8);

3. percent cover of sessile invertebrates, turf algae, and geologic habitat characteristics are estimated from UPC along transects on the reef, and;

4. size frequency data for the commercially and ecologically important invertebrates such as red and purple urchins, abalone and other key species.

Further description of the PISCO survey methods can be found at the following website: http://www.piscoweb.org/research/science-by-discipline/ecosystem-monitoring/kelp-forest- monitoring/subtidal-sampling-protocol

Table 2-8: PISCO Survey Swath Species List. Algae Macrocystis adult (>30cm): plants and stipes/plant Eisenia ad (>30cm) Pterygophora adult (>30cm) Dictyoneurum californicum Cystoseira (diameter>6cm) Dictyoneuropsis reticulata Laminaria ad (width>10cm) Alaria marginata Invertebrates Lytechinus anamesus (>2.5cm) Anthopluera xanthogrammica S. purpuratus(>2.5cm) Cancer spp. S. franciscanus(>2.5cm) Pugettia producta Tethya aurantia Pugettia richii Urticina lofotensis Loxorhychus grandis Other Urticina Loxorhychus crispatus Asteroids unid. Panulirus interruptus Asterina miniata Aplysia californica Dermasterias imbricata Lithopoma undosum Henricia leviuscula Lithopoma gibberosum Orthasterias koehleri Crassedoma giganteum Mediaster aequalis Megathura crenulata Pisaster brevispinus Kelletia kelletii Pisaster giganteus Cryptochiton stelleri

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Pisaster ochraceous Cypraea spadicea Pycnopodia helianthoides Haliotis corrugata (pink) Parastichopus californicus Haliotis cracherodii (black) Parastichopus parvimensis Haliotis rufescens (red) Anthopluera elegantissima Haliotis fulgens (green) Anthopluera sola

Twelve historical rocky subtidal monitoring sites are documented in the vicinity of Broad Beach (Table 2-9). However, some uncertainty exists regarding monitoring status, sampling frequency, and available data for several of these locations because detailed site descriptions are not available for the rocky subtidal sites (in contrast to the rocky intertidal sites, which benefit from detailed site descriptions). Table 2-9 summarizes the monitoring locations, ASBS designation, MPA status, and year sampled.

Table 2-9: Rocky Subtidal Monitoring Sites in the Vicinity of Broad Beach from Northwest to Southeast Year Sampled Site ASBS # MPA Status 2004 2008 2011 2012 Deep Hole East * 24 - - - x x x County Line West** - - - County Line East** - - - Leo Carrillo East* 24 Point Dume SMR - x x x Nicholas Canyon West* 24 - - - x - - Encinal Canyon East * - Point Dume SMCA MPA - - x x Point Dume * 24 Point Dume SMR MPA - x x x Point Dume West** - Point Dume SMR MPA Point Dume East** - - - Little Dume West* 24 Point Dume SMR MPA - x x x Escondido West* 24 - - - x - - Malibu Bluffs - - - x - - - *site summary data available as part of 2008 Regional Monitoring Program **sampling history unknown The following section provides a brief summary of findings for each site. Table 2-10 provides the mean percent cover of substrate type and relief present at each site. Table 2-11 lists the abundance and percent cover of benthic indicators from rocky subtidal monitoring sites in the vicinity of Broad Beach. Urchin barrens were found at Deep Hole and Point Dume, and urchin density was inversely related to kelp density and understory algae density (Pondella et al. 2012). There was also a high percent cover of sand tolerant tube worms (i.e. Phragmatopoma and Diopatra) at four of the six sites, suggesting high sediment loads (Pondella et al. 2012).

Table 2-10: Percent Cover of Substrate Type and Relief of Rocky Subtidal Monitoring Sites in the Vicinity of Broad Beach (from Pondella et al. 2015b) Substrate Relief Bight ’08 Reef Bedrock Bolder Cobble Sand 0-0.1m 0.1-1m 1-2m >2m Deep Hole* 65 18 4 14 9 10 - Leo Carrillo 36 15 3 46 56 35 9 2- Nicholas Canyon* 7 28 16 48 40 6 Point Dume* 13 6 27 - 44 18 39 Little Dume 15 19 38 28 56 44 Escondido* 2 14 27 4 32 68 *percent cover does not total 100 for one or both parameters for unknown reason.

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Table 2-11: Abundance and Percent Cover of Indicators from Rocky Subtidal Monitoring Sites in the Vicinity of Broad Beach (from Pondella et al. 2012)

Purple White Understory Giant Kelp % % Bight ’08 Reef Urchin Urchin Kelp (#/100m2) Bare Rock Tubeworms* (#/100m2) (#/100m2) (#/100m2) Deep Hole 759.7 2.1 12.1 10.4 0.0 0.8 Leo Carrillo 232.5 0.6 22.2 25.8 0.5 16.7 Nicholas Canyon 96.2 0.0 32.1 12.1 1.6 31.5 Point Dume 754.2 0.0 6.7 10.8 8.1 3.2 Little Dume 19.6 0.0 23.9 116.0 2.2 10.8 Escondido 9.2 0.0 27.9 0.0 4.8 16.1 *includes Phragmatopoma and Diopatra Reef structure, classified by relief and substrate, was summarized in Pondella et al. 2012. Five of the six sites in proximity to Broad Beach (Deep Hole, Leo Carrillo, Nicholas Canyon, Little Dume, and Escondido) were grouped in the cold temperate mainland biogeographic province, while Point Dume (in the lee of Point Dume) was grouped in the warm temperate mainland biogeographic province. When examining conditions of structure and assemblages of reefs at Lechuza Point, this reef complex should similarly group with others in the vicinity under the cold temperate mainland biogeographic province.

Pondella et al. 2012 concluded that the nearshore rocky reefs in the Southern California Bight are highly variable in terms areal extent and physical habitat structure. This same study also concludes: a) based upon relief and substrate characteristics alone, five major reef types exist in the Southern California Bight; and b) efforts should be undertaken to understand the influence of reef habitat characteristics (substrate type, rugosity, and relief) on the associated biota.

One objective of the baseline program was to assess candidate system indicators and examine potential new candidates to assist in assessing impacts of human disturbance and general environmental quality (Pondella et al 2015a). The findings note that specific indicators will depend on the specific management or ecological objectives, but at a minimum they should be:

1. Easy to measure (e.g., cost-effective, readily observed/identified, relatively common) 2. Suitable for statistical analyses or ‘robust’ (e.g., low random variation among samples) 3. Indicate something: a. be sensitive to anthropogenic perturbations or a manageable human activity in a predictable way, and/or, b. be a strong ecological driver 4. Applicable to a variety of temporal and spatial scales as well as habitats

Differing from the regional trends and conservation effectiveness assessments undertaken for the subtidal monitoring effort, this Project specific MHMMP seeks to determine discrete impact assessment by determining if and to what extent various habitats have been affected by the influence of the Project. In the case of the MPA monitoring, transects extend across reefs and sand and treat the habitats as a collective with some of the sites supporting nearly 50 percent sand bottom. With such sampling methodology, it would be difficult to statistically distinguish sand effects on rock with a manageable extent of sampling. For this reason, sampling is planned to be distinctly allocated to the rocky reef habitats and adjacent vertical surfaces to best detect any changes within the habitats. Considering the breadth of data available within the AoPE, as well as at nearby subtidal rock reef habitat, a modified version for crane sampling will be integrated in development of the monitoring methods and selection of reference sites.

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Kelp Canopy

Perhaps the most extensive and widespread monitoring history of a marine habitat resource in California has been the distribution of giant kelp based on the extent of kelp canopy. At present, the most extensive continuous surveys have been completed by the CDFW using aerial infrared (IR) photography. These survey data are available from at least 1989 through 2014 (ftp://ftp.dfg.ca.gov/R7_MR/BIOLOGICAL/Kelp/). In 2003, a more comprehensive and rigorously controlled monitoring program was implemented to monitor kelp canopy off of Ventura, Los Angeles, Orange, and San Diego counties. This program was the Central Region Kelp Survey Consortium (CRKSC) developed as a result of regulations adopted by the Regional Board and follows closely with the structure of the Region Nine Kelp Survey Consortium formed in 1983 for the southern coastline. The consortium programs have been implemented synoptically since development and provide a good overall characterization of kelp canopy conditions from Ventura Harbor to the U.S./Mexican Border.

In order to best interpret long-term conditions of kelp canopy within the region, a kelp canopy frequency distribution map was prepared that composites data from 1989 through 2014 and presents information as frequency of kelp occurrence (Figure 2-5). This mapping indicates that the maximum frequency of occurrence of mapped canopy in the prior data sets has been 9 of 15 years, or 60.3 percent of the mapping years have illustrated the presence of kelp canopy at any given location within the mapping region.

Since 2003, the monitoring program for the CRKSC has evolved into a well-structured monitoring program. This program uses quarterly flights over all of the surveyed beds. From this process, each quarterly survey is used to generate orthomosaics depicting the kelp habitat that are Photo 2-13: The kelp canopy within Broad Beach reflects the mosaic of expansive and spotty bedrock reef below. ranked against the Average Bed Area Per Year (ABAPY) While the manifestations of the surface canopy are dependent condition (MBC 2015 and 2016). After all four quarterly upon a number of factors, during late summer and fall, most surveys are completed, a composite of the quarterly mosaic kelp beds are reflected on the water surface (top). The kelp beds within the AoPE are generally moderately open relative images that depict the maximum annual canopy achieved to some of the larger beds in the region, although the more for each bed is developed for the region. This is not a extensive beds at the west end of the AoPE do provide composite of all quarters at a single site, but rather the most considerable structure to the water column (middle). Portions of the AoPE are limited in capacity to support kelp extensive kelp for any quarter at a site combined with the bed expansion due to lack of available substrate. In some most extensive kelp per single quarter for other sites. By cases, the bedrock outcrop is nearly fully defined by a single developing this annual snapshot of the kelp canopy, the massive holdfast of giant kelp (bottom). repeated sampling composite methodology dampens variance associated with site differences in kelp elongation, current and wave environments, or cloud cover during a single flight. Surface canopy of kelp under this program is mapped using the image classification functions of ArcGIS® and spatial analyst tools.

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The California Fish & Game Commission designated administrative kelp bed leases for granting and management of exclusive harvest lease opportunities in the early 1900s. As such, these administrative kelp bed lease boundaries provide the framework for tracking kelp canopy coverage from 1911 through 1989. For continuity purposes, these administrative boundaries have been retained to segment beds in present monitoring programs, although much more discrete bed accounting within these blocks is now employed as named segments within the lease blocks. CDFW administrative kelp bed leases 16 and 17 in the Central Region correspond nearly precisely with the defined Project region extending from Mugu Lagoon to Malibu Lagoon (Figure 2-15). No leased harvesting is presently occurring in these beds; however, mechanical harvesting has been proposed in Beds 17 (Mastrup 2015, as reported in MBC 2016). No harvesting would be allowed within any MPA. Annual maximum kelp canopy data for the period 2003-2015 has been extracted from the CRKSC survey report for CDFW Beds 16 and 17 in order to evaluate kelp canopy variability within the region and to evaluate the potential for using these data and this program as a means of assessing kelp canopy impacts from the Broad Beach Project (Table 2-12).

Figure 2-15: CDFW Administrative Kelp Bed Lease Areas Depicting Location of Beds 17 and 16 (adapted from MBC 2016).

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Table 2-12: Kelp Canopy Historic Maximum Annual Extent in CDFW Beds 16 and 17 (MBC 2016)

Canopy Area (km2) Kelp Bed 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Pt. Dume 0.012 0.029 0.028 0.053 0.065 0.070 0.104 0.094 0.078 0.154 0.113 0.092 0.169 Paradise Cove 0.162 0.258 0.035 0.036 0.100 0.223 0.244 0.259 0.109 0.346 0.244 0.223 0.086 Escondido Wash 0.214 0.250 0.078 0.339 0.278 0.321 0.267 0.104 0.248 0.243 0.281 0.095 Latigo Canyon 0.125 0.161 0.032 0.007 0.186 0.124 0.195 0.142 0.070 0.202 0.133 0.212 0.052 Puerco/Amarillo 0.074 0.051 0.039 0.055 0.095 0.064 0.115 0.126 0.069 0.153 0.105 0.130 0.034 Malibu Pt. 0.011 0.013 0.008 0.008 0.016 0.011 0.012 0.066 0.074 0.084 0.060 0.039 Total F&W 16 0.598 0.762 0.220 0.158 0.801 0.769 0.991 0.954 0.504 1.189 0.897 0.976 0.436 Deer Creek 0.089 0.107 0.053 0.026 0.046 0.074 0.105 0.062 0.055 0.041 0.104 0.103 0.124 Leo Carrillo 0.318 0.399 0.171 0.150 0.145 0.207 0.255 0.232 0.226 0.337 0.366 0.261 0.408 Nicolas Canyon 0.308 0.362 0.195 0.038 0.473 0.268 0.433 0.291 0.130 0.240 0.369 0.288 0.347 El Pesc/La 0.243 0.314 0.141 0.063 0.255 0.173 0.238 0.164 0.136 0.173 0.236 0.244 0.246 Piedra Lechuza 0.105 0.104 0.041 0.022 0.106 0.075 0.105 0.096 0.096 0.066 0.154 0.137 0.119 Total F&W 17 1.063 1.286 0.600 0.298 1.025 0.797 1.136 0.844 0.642 0.857 1.229 1.034 1.244

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In general, the defined bed breaks used in the CRKSC monitoring program are appropriate to define reference areas as discussed later. However, the bed defined as “Lechuza” under the CRKSC extends much further upcoast than does the defined AoPE (Figure 2-16). As a result, if this bed were used in full as an indicator of potential impact in the assessment of the Broad Beach sand nourishment program, the extended scale of the bed may dilute the capacity to detect effects if they are present. As such, it is recommended that, going forward, the Lechuza bed be split in any future consideration relative to the Broad Beach Project.

Examination of Table 2-12 reveals that the kelp canopy for the Lechuza bed is on the smaller scale of the 11 individual beds mapped in the Broad Beach region. The table also suggests that the variability in canopy size at Lechuza is generally less than observed at several other beds in the region.

Overall, Lechuza displayed few similarities in terms of the annual change in canopy cover with any of the other kelp beds. While the majority of the trends in kelp canopy in the region have also been reflected at Lechuza, there have been some notable exceptions. In 2011 most beds declined relative to Lechuza and most beds increased relative to Lechuza in 2012 (Table 2-12 and Figure 2-17). Notably, Deer Creek has tracked very similarly with Lechuza during this period and through most of the monitoring period. Even more interestingly is that Deer Creek and Lechuza define the westerly and easterly terminal beds, respectively, within the CDFW kelp lease 17. While it is not safe to assume the beds at Lechuza Point will track consistently with any other bed on an individual basis, the natural response of Lechuza Point kelp does appear to fall within the high and low limits of kelp canopy reported for the region.

Figure 2-16: Lechuza Kelp Bed from CRKSC in Relationship to the Broad Beach AoPE (adapted from MBC 2016)

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Figure 2-17: Maximum Annual Kelp Canopy by Bed within Broad Beach Study Region based on CRKSC data Soft Bottom Habitat

Substantial research revealed no unvegetated soft bottom habitat sampling programs that are directly applicable to the Broad Beach monitoring plan area. In general, soft bottom sampling within the Southern California Bight has focused on outfalls to deeper waters and broad characterization of the Bight through limited grab sampling. This work has generally been performed through coordinated efforts by multiple parties organized under the Southern California Bight Regional Monitoring Program. In 2008 and 2013, sampling was performed in waters offshore of the Malibu coastline in proximity to Broad Beach. However, these sampling efforts occurred in much deeper waters and are not relevant to the areas of concern for the present program. Because potential impacts of the Project would occur to very shallow waters that are typically not regularly sampled on the open coast, there is a general paucity of regional data.

For eelgrass habitat, NMFS and other partners are implementing regional investigations to inventory eelgrass throughout the Southern California Bight and monitoring eelgrass habitat distribution and variation as a means to track long-term trends in the environment. This multi-year effort follows recommendations for a Southern California Eelgrass Monitoring Program (Bernstein et al. 2011) and includes benchmark inventories and monitoring of eelgrass within both enclosed bays and estuaries as well as open coastal and insular environments. In 2015, National Oceanic and Atmospheric Administration (NOAA) Fisheries contracted for completion of eelgrass surveys along Santa Monica Bay from Marina del Rey to Ventura County, eastern Santa Cruz Island, the Santa Ana River, and the Huntington Beach Wetlands Complex (Merkel & Associates 2015). Surveys included inventories throughout the entire shoreline region encompassing Broad Beach and potential reference sites. The survey documented the presence of 13.7 acres of eelgrass coverage from Marina del Rey to Point Dume and 21.1 acres of eelgrass coverage from Point Dume to the Los Angeles/Ventura County Line.

Surveys also examined depth distribution of eelgrass and found a much greater depth range for eelgrass located to the west of Point Dume than to the east of Point Dume. The depth distribution of eelgrass on the mainland coast revealed a somewhat unexpected pattern of distribution. The shoreline areas west of Point

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Dume are more exposed than areas to the east of Point Dume. Eelgrass beds were expected to be distributed deeper to the west of Point Dume. However, there was little difference in the shallow edge of eelgrass beds east or west of Point Dume. Beds extended as shallow as ‐20 ft MLLW to the east of Point Dume and ‐22 ft MLLW to the west of the point (Figure 2-18). Eelgrass extends much deeper to the west of Point Dume (‐58 ft MLLW) than to the east of Point Dume (‐40 ft MLLW). The depth distribution of eelgrass east of Point Dume was consistent and narrow, with 90 percent of all the mapped eelgrass occurring between ‐26 and ‐33 ft MLLW. Conversely, to the west of Point Dume, 90 percent of all the eelgrass extends between ‐26 and ‐39 ft MLLW. The skewed occurrence of eelgrass towards deeper environments west of Point Dume suggests that light may be a factor limiting eelgrass to the east of Point Dume since, both east and west of Point Dume, the bottom below the eelgrass beds tends to continue as a gradually sandy slope that would otherwise be suitable habitat to support eelgrass.

The relatively substantial difference in depth distribution between areas east and west of Point Dume suggest that waters of Santa Monica Bay may be substantively more turbid, on average, than waters on the more exposed coastline of the southern Santa Barbara Channel where Broad Beach occurs. When evaluating habitats known to be highly affected by persistent or long-term pulsed elevated turbidity levels or other factors that may reduce the ambient subtidal light environment, this fact suggests focusing on reference areas sited to the west of Point Dume rather than the east.

Figure 2-18: Eelgrass Depth Distribution along the Marina del Rey to Ventura County Shoreline from 2015 Southern California Bight Regional Eelgrass Surveys (from Merkel & Associates 2015)

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

REFERENCE SITE SELECTION

REFERENCE SITE OBJECTIVES The CDP requires the monitoring of a minimum of two reference sites for each of the evaluated habitat types. The reference sites should be as close as possible to the potential impact area but outside the Project’s influence and have similar marine habitats as the Project area. Selection of sites should be performed in consultation with the applicant, resource agencies, and the SAP.

In order to evaluate the Project’s effects, reference sites will serve as un-impacted controls. The pre- construction relationship between the AoPE and reference site conditions will serve as the baseline condition in which post beach nourishment conditions will be compared. While it is expected that conditions within the AoPE and reference sites will vary, it is anticipated that sites will generally respond similarly to natural conditions within the region and thus will follow similar patterns of change through time. Deviations in habitat classes and biotic features documented within the AoPE as compared to reference sites consistent with impact assessment criteria, presented in Section 5 will be assumed to be a Project impact unless the BBGHAD presents compelling evidence that demonstrates a weight of evidence approach that proves otherwise. The resource agencies will make their own independent determination regarding what is or is not considered a project impact. The weight of evidence approach may include biological and/or physical data collected under this program, or a consideration of how reference sites and the AoPE are responding to anthropogenic or regional events.

To improve the ability to assess how the AoPE behaves compared to reference sites, reference sites must be both physically and biologically similar from within the same regional area and containing similar habitat components. Reference sites were sought that could meet the following criteria:

 The requirement for being proximate to the AoPE;  Similarity in physical site conditions to those exhibited within the AoPE;  Similarity in physical site dynamics to those exhibited within the AoPE;  Available baseline data that indicates similarity in biological conditions to the AoPE;  Accessibility on a regular basis at all daylight hours; and  Presence of multiple habitats to optimize monitoring efficiencies. REFERENCE SITE EVALUATION METHODS The area considered for reference site identification was situated around the 2-mile-long AoPE and extended over a 10-mile segment of coastline upcoast to Mugu Lagoon and along a 10-mile segment downcoast to Malibu Lagoon. This is the same area investigated for presence of other regional data that would support development of the monitoring program (Figure 3-1).

A primary interest in the identification of suitable reference areas is the identification of sites subjected to similar coastal processes as the AoPE. In addition, to the extent practical and knowable, sites should experience similar energy environments, have similar shoreline topology, geology, and substrate conditions as the AoPE. Sites should be selected in a manner that also considers watershed inputs to the nearshore and intertidal environments. Finally, consideration should be given to water quality and water mass exposure as it may influence the dynamics of marine habitats.

To address these selection objectives, multiple paths were pursued to explore potential reference site options. These included:

 Evaluation of the broad scale characteristics of the region relative to oceanic processes. This included collection and review of NOAA navigation charts for the region that could be used to

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

assist in understanding the continental shelf conditions and nearshore bathymetry, large-scale wave shadowing, and overall shoreline orientation (Table 3-1). In addition, data from the Southern California Coastal Ocean Observing System (SCCOOS) (sccoos.org) and the Coastal Data Information Program (CDIP) (cdip.ucsd.edu) were reviewed to determine if there were any substantial differences in surface currents or wave environments within the reference site study region.  Evaluation of the shoreline topology, habitat distribution and history, as well as public accessibility. This element was strongly guided by a methodical review of Google Earth imagery and historic photo records followed by review of other photographic data, such as the current and historic data available from the California Coastal Records Project (californiacoastline.org). Through multiple scans of the data, the entire region was searched for shoreline topology, coastal orientation, watershed drainage patterns, geometric scale, and habitat resource representation that were comparable to that represented within the AoPE. In particular, prominent bedrock headlands with downcoast coves and trailing beaches were sought. Following this search, no sites emerged that matched the AoPE perfectly. As such, subsequent shoreline reviews were conducted in an iterative process of lowering the rigidity of criteria with each progressive review. The parameters relaxation progressed by modification rather than omission of factors. Using this approach, it was possible to identify apparent “best fit” sites that could have the capacity to serve as reference sites for the AoPE habitats.  Evaluation of existing biological monitoring data for programs that include sites within the region, as discussed in Section 2.2 of this Plan. The principal observations from these programs are that their sampling objectives generally do not align well with the monitoring needs for the Project. However, the programs do provide insights into resources in the area and, in some cases, the dynamics and variance between sites and seasons. These existing programs tend to focus on more stable higher rocky bench environments in the case of the rocky intertidal sampling, or broad scale patterns with limited temporal sampling in the case of subtidal reefs and sand beach programs. The most complete and applicable monitoring programs have focused on kelp canopy distribution within the region. This has included the CDFW aerial survey monitoring program, UCSB Coastal Long-term Ecological Research Project (LTER), kelp canopy biomass monitoring using Landsat 5 Thermatic Mapper (TM), and the CRKSC aerial survey mapping programs. Of these, the CRKSC kelp monitoring follows the most robust and appropriately scaled study program with respect to the kelp canopy monitoring needs of the MHMMP. Finally, sites were investigated to ensure opportunities for efficiently accessing reference sites considering tidally constrained survey requirements and to evaluate potential interference or site disturbance risk by the public, as well as other logistical factors. This was done by reviewing hours of operation for park lands, discussing access with locals and park staff, and visiting shortlisted candidate sites. REFERENCE SITES CONSIDERED One way to help ensure an area of interest has a high potential to behave similarly to reference areas is to select reference areas physically similar and located relatively close to it. The premise is that nearby areas with similar physical characteristics should support similar biota, which should fluctuate similarly over time. In addition to proximity, other criteria used to select the reference areas should include having similar sediment sources, habitat such as low and high-relief rocky substrate, and similar biological components. Therefore, a series of criteria were developed to assist in the selection of potential reference sites. As indicated, criteria were initially identified as stringent constraints, then relaxed through the process due to the sites’ inability to meet such stringent standards. The final screening criteria are outlined as follows:

1. Similar habitat components present as the AoPE; 2. Serve as reference for other habitat components of interest; 3. Similar headland with adjacent beach as AoPE;

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

4. Within 5 miles of the AoPE; 5. Similar coastal orientation as the AoPE; 6. West of Point Dume; 7. Similar depth profile as the AoPE; 8. Same sediment sources; 9. Publicly accessible; and 10. Existing data available.

Data from existing monitoring locations (e.g., PISCO, MARINe, MPA, ASBS, Bight) comprising rocky intertidal, sandy intertidal, rocky subtidal, and kelp canopy were assembled and reviewed to select potential reference sites in the vicinity of the AoPE. Table 3-1 summarizes the habitat components of interest or those anticipated to be monitored at the AoPE to note presence, absence, or if no data exists. Using the best available information, Sequit Point, Leo Carrillo, El Pescador, and El Matador supported the most similar habitat components of interest present in the AoPE. Table 3-2 summarizes how well the potential reference sites met the criteria noted above. Results indicate that Sequit Point, Leo Carrillo, El Pescador, and El Matador met all ten criteria; other sites met fewer criteria. Additionally, monitoring conducted in spring 2017, consistent with the May 2017 draft version of this MHMMP, was performed in the AoPE and the selected reference sites. Monitoring was completed for all habitats types and biotic features and evaluated in terms of similarities between the AoPE and reference sites. Ultimately Leo Carrillo and Sequat Point were combined into one reference site to configure a rocky intertidal site most similar to the AoPE. Results indicated that Leo Carrillo/Sequat Point was very similar in habitat class (substrate) and biotic features (functional groups/species) as the AoPE in many cases.

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Table 3-1: Habitat Components of Interest for Potential Reference Sites Habitat Mapped Habitat Broad Beach Old Stairs Deer Creek Sequit Point Leo Carrillo El Pescador El Matador Point Dume Paradise Cove Malibu Bluffs Classification Marine Nearshore: Supratidal Vegetated Dune Not Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Unvegetated Dry Beach Not Present Present Present Present Present Present Present Present Present Present Artificial Substrate Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Marine Nearshore: Intertidal Bedrock or Large Present Present Present Present Present Present Present Present Present Present Marine: Intertidal: Boulders Rock Bottom Surfgrass Present Present Present Present Present Present Present Present Present Present Rubble/Cobble Present Present Present Present Present Present Present Present Present Present Marine: Intertidal: Rip Rap Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Not Present Artificial Substrate Marine: Intertidal: Sand Beach Present Present Present Present Present Present Present Present Present Present Unconsolidated Bottom Kelp Wrack Varies Varies Varies Varies Varies Varies Varies Varies Varies Varies Marine Nearshore: Subtidal Bedrock with Kelp Present Not Present Present Present Present Present Present Present Present Present Marine: Subtidal: Bedrock/Boulder Present Not Present Present Present Present Present Present Present Present Present Rock Bottom Rubble/Cobble Present Not Present Present Present Present Present Present Present Present Present Surfgrass Present Unknown Unknown Present Present Present Present Present Present Present Marine: Subtidal: Unconsolidated Sand Bottom Present Present Present Present Present Present Present Present Present Present Bottom Eelgrass Present Not Present Not Present Present Present Present Present Not Present Not Present Present Note: Shaded rows are censused for completeness of spatial inventory but are not considered in project impact assessments

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Table 3-2: Reference Site Selection Matrix Criterion Broad Beach Old Stairs Deer Creek Sequit Point Leo Carrillo El Pescador El Matador Point Dume Paradise Cove Malibu Bluffs Similar habitat components of interest as NA Yes Yes Yes Yes Yes Yes Yes Yes Yes Broad Beach Serve as reference for some or all habitat NA No eelgrass or kelp No eelgrass Yes Yes Yes Yes No eelgrass No eelgrass Yes components of interest Similar physical characteristics as Broad Beach (rocky headland/point, adjacent NA No No Yes Yes Yes Yes No Yes Yes sandy beach) Close proximity (±5 miles) NA No No Yes Yes Yes Yes Yes Yes No Similar coastal orientation South (S) Yes (SE) Yes (SE) Yes (S) Yes (S) Yes (S) Yes (S) Yes (S) Yes (SE) Yes (S) West of Pt. Dume (westerly exposure) Yes Yes Yes Yes Yes Yes Yes No No No Similar depth profile NA No No Yes Yes Yes Yes No No Yes Dume Creek; Ramirez Canyon Ramirez Canyon Creek; Escondido Latigo Canyon Encinal Canyon San Nicholas San Nicholas Lachuza Creek; Lachuza Creek; La Jolla Canyon; Sycamore Canyon; Creek; Escondido Canyon Creek; Creek; Solstice Nearby Sediment sources Creek; Trancas Canyon Creek; Canyon Creek; Encinal Canyon Encinal Canyon Sycamore Canyon Deer Creek Canyon Creek Latigo Canyon Creek; Malibu Sequit Creek Sequit Creek Creek Creek Creek Latigo Canyon Creek; Solstice Creek Creek Creek Publicly accessible Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Existing data Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Selected NA No (6 of 10) No (6 of 9) Yes (10 of 10) Yes (10 of 10) Yes (10 of 10) Yes (10 of 10) No (6 of 10) No (7 of 10) No (7 of 10)

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

REFERENCE SITES SELECTED Using the screening criteria identified and the reference site selection matrix, reference sites have been selected for each of the evaluated intertidal and subtidal habitat elements. The selected reference sites generally include multiple habitats contained within the broader reference sites in order to provide monitoring efficiencies, as well as to facilitate examination of habitat conversion from one habitat to another in a manner similar to conversion monitoring (monitoring of redistribution of spatial extent between feature classes) within the AoPE.

The reference sites for each habitat type are shown in Figure 3-1 and indicated in Table 3-3. The reference sites for rocky intertidal and subtidal habitats are located upcoast of Broad Beach, while the reference sites for intertidal sand beach are located both upcoast and down coast of Broad Beach. Leo Carrillo and Sequit Point were combined to form Leo Carrillo/Sequit Point in order to take advantage of their similarities with the AoPE with respect to habitat extent, feature class composition, and biotic community density and diversity. The AoPE is adjacent to Zuma Beach and shares many physical and biological similarities in terms of sand beach. More so, the lack of sand beach north of the AoPE reduced the available options for suitable sand beach reference sites, reflected by the inclusion of Zuma East.

For kelp canopy, the CRKSC monitoring program mapping data are to be adopted using defined bed segments within the CDFW administrative lease beds 16 and 17, except for the additional split of the Lechuza beds into a West Lechuza (upcoast of the AoPE) and East Lechuza (within the AoPE). These CDFW administrative lease bed boundaries are depicted in Figure 2-15. This generates 11 reference beds with five being located upcoast of AoPE and 6 being located downcoast of the AoPE.

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Figure 3-1: Habitat Reference Site Locations Relative to the AoPE

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Table 3-3: Reference Sites for Each Monitored Habitat Element Habitat Element Reference Sites Supratidal (Marine: Nearshore) Bedrock  Leo Carrillo/Sequit Pt.  El Pescador (Geologic Substrate: Rock Substrate)  El Matador* Rip Rap Not evaluated (Anthropogenic Substrate: Anthropogenic Rock) Boulder/Cobble  Leo Carrillo/Sequit Pt.  El Pescador (Geologic: Unconsolidated Substrate)  El Matador* Sand  Leo Carrillo  Zuma East (Geologic: Unconsolidated Substrate)  El Pescador Intertidal (Marine: Nearshore) Bedrock  Leo Carrillo/Sequit Pt.  El Pescador (Geologic Substrate: Rock Substrate)  El Matador Rip Rap Not evaluated (Anthropogenic Substrate: Anthropogenic Rock) Boulder/Cobble  Leo Carrillo/Sequit Pt.  El Pescador (Geologic: Unconsolidated Substrate)  El Matador Sand  Leo Carrillo  Zuma East (Geologic: Unconsolidated Substrate)  El Pescador Surfgrass Bed  Leo Carrillo/Sequit Pt.  El Pescador  El Matador Subtidal (Marine: Nearshore) Bedrock Reef  Leo Carrillo  El Pescador (Geologic Substrate: Rock Substrate)  Sequit Pt.**  El Matador** Boulder/Cobble Reef  Leo Carrillo  El Pescador (Geologic: Unconsolidated Substrate)  Sequit Pt.**  El Matador** Sand  Leo Carrillo  Zuma East (Geologic: Unconsolidated Substrate) Canopy-Forming Algal Bed (Kelp Beds)  CRKSC Beds + West Lechuza Eelgrass Beds  Leo Carrillo  El Pescador  El Matador * Peripheral resource mapped as boundary condition, but not evaluated as a habitat metric under this plan. ** Habitat change analysis, no monitoring for subtidal assemblages is included.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Leo Carrillo Leo Carrillo State Park has been identified to support a reference area for all habitat elements (Leo Carrillo). A separate reference area (Sequit Point) has been added for subtidal habitat extent discussed separately. The Leo Carrillo site is immediately adjacent to Sequit Point and the sites have been combined (Leo Carrillo/Sequit Point) to serve as a reference for rocky intertidal habitat and surfgrass. These sites have been combined and selected due to its headland, cove, and downcoast trailing beach configuration similar to Lechuza Point, Lechuza Cove, and the AoPE. Leo Carrillo/Sequit Point is located only 4 miles to the west of Broad Beach and has all the same geological features (bedrock, boulder/cobble, and sandy intertidal and subtidal features), as well as the biotic communities of intertidal and subtidal habitats, including specific resources of interest (giant kelp, surfgrass, and eelgrass beds). The coastal exposure aspects and bathymetry of the nearshore shelf are similar between Leo Carrillo/Sequit Point and the AoPE. The headlands at Leo Carrillo/Sequit Point do not generate the same extent of protected cove as found at Lechuza Cove. This may be the result of continued episodic influx of sediment, including larger boulders from Arroyo Sequit that prevents the development of the deep notch seen at Lechuza Cove. However, in terms of shoreline morphology within the study region, Leo Carrillo/Sequit Point is the best match with the AoPE.

The lack of beach maintenance and presence of a natural back beach environment to the east of the point makes Leo Carrillo a good candidate for beach sampling in a natural area comparable to the Broad Beach environment. The site does not have a wide upper beach margin, instead intersecting with a steep bluff area only a short distance back from the beach crest. With considerable aggregated cobble on the back beach, the conditions suggest that during extreme storm events, this beach occasionally erodes back to the bluff and rebuilds. Wrack does Photo 3-1: Leo Carrillo has a headlands, cove and trailing accumulate on the beach at Leo Carrillo. The beach beach topology similar to Lechuza Point and Broad Beach transitions into Nicholas Canyon County Beach. and is located only 4 miles upcoast of Broad Beach; however, Arroyo Sequit draining into the cove is much larger than Steep Hill Canyon entering Lechuza Cove (top). The site The area is easily accessible through the State Park, which supports partially sanded boulder/cobble beds (top middle) also detracts from the site, since the park receives a fairly and a bedrock headland with both high and low elevation intensive amount of public use within the rocky headlands intertidal rock supporting surfgrass (bottom middle). Intertidal resources experience similar scour and thermal and tidepool areas that may adversely affect the faunal and stresses as were noted within Lechuza Cove (bottom). algal communities. However, the Project monitoring program focuses on common sessile indicators rather than less common and easily collectable organisms that may be disproportionately affected by people. As such, the tide pooler traffic is not expected to substantively alter site conditions and the intensity of disturbance is not anticipated to change substantively over time. Thus, it can reasonably be expected that human stressor conditions will not alter the site condition in a

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan manner that results in directional trends. For the boulder field and sand beach, it is possible to locate sampling further down the beach to the east of the primary access; thus, substantially reducing artifacts of human-associated impacts in these intertidal habitats. For subtidal habitat, little concern exists for human- induced disturbance of a substantial nature since the extent of consumptive activities remains relatively low in this area.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Sequit Point The addition of monitoring at Sequit Point was based on SAP and regulatory staff recommendations to incorporate additional sites early in the monitoring program to reduce the risk of not identifying adequate reference sites prior to Project initiation. Sequit Point is located just 750 feet (200 m) west of the Leo Carrillo reference site. The inclusion of Sequit Point provides an additional reference site of changes in habitat classes (rock, cobble, sand, kelp, etc.) and the combination with Leo Carrillo for rocky intertidal and surfgrass provides a much-needed rocky intertidal bench condition (Photo 3-2, middle) found on outer Lechuza Point. Based on PISCO monitoring data, Sequit Point does not appear to experience as much sand influence as Lechuza Point, but adjacent down coast boulder/cobble and surfgrass habitat are similar in extent and structure to the AoPE. In addition, Sequit Point provides defined vertical scarps along the bench similar to Lechuza Point

Sequit Point also does not have an immediate trailing beach, but rather the point generates a small pocket cove in its lee due to the presence of the secondary headland down coast of Sequit Point within the Leo Carrillo reference site.

The principal reason for the Sequit Point monitoring site inclusion relates to the addition of rocky intertidal habitat and another subtidal feature class reference site. Proposed reference site monitoring at this site includes monitoring of the rocky intertidal headland, habitat mapping of the subtidal and intertidal habitats for change analyses, and monitoring of surfgrass. Intertidal beach, subtidal sand, and subtidal reef monitoring inclusive of direct sampling is not proposed at this location.

Photo 3-2: Sequit Point is a platform headland that is topologically similar to Lechuza Point on the headland itself (top). However, Sequit Point lacks a trailing beach; rather it supports a leeward pocket beach. The headland is generally gently sloping to the southwest with a scarped edge that drops vertically to sand below (top middle). The elevation of sand rises and falls against the headland but generally does not reach the elevation of the rocky platform. The site has been used as a PISCO monitoring site and has had biodiversity sampling performed in 2009 and 2013. The headland supports a miex of barnacles, mussels, macroalgae, and a high proportion of bare rock (bottom middle). Rock bolts from this sampling are evident on the point (bottom).

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

El Pescador El Pescador has been identified to serve as a reference area for all habitats, including sand beach. The sand beach at this site is of limited length at approximately 800 ft long and is backed by a steep bluff similar to the natural topology of the AoPE shoreline.

El Pescador has been selected due to its morphometric similarity to the AoPE, except for its less pronounced shoreline concavity and less well developed bedrock headlands. The site is located approximately 2 miles to the west of the AoPE, and has all the same geological features (bedrock, boulder/cobble, and sandy intertidal and subtidal features), as well as the biotic communities of intertidal and subtidal habitats, including specific resources of interest (giant kelp, surfgrass, and eelgrass beds). The coastal exposure aspects and bathymetry of the nearshore shelf are similar between El Pescador and the AoPE. The point does not generate the same extent of protected cove as found at Lechuza Cove, although episodic influx of sediment from Decker Canyon may be similar to Steep Hill Canyon within the AoPE.

The site is reasonably accessible with a locked gate open

during daylight hours, a small parking lot, and steep trail to the beach. The site does not experience as much public use as other parks within the area; therefore, the rocky headlands, tidepool areas, and faunal and algal communities may exhibit lower anthropogenic impacts than at Leo Carrillo and be more similar to Lechuza Point. For the rocky intertidal habitat, two locations within the cove have been defined and will be monitored as rocky point and boulder/cobble reference locations. For subtidal habitat, there is little concern for human-induced disturbance of a substantial nature since the extent of consumptive activities is believed to be relatively low in this area. Photo 3-3: El Pescador has a small headland, cove and trailing beach topology similar to Lechuza Point and Broad Beach and is located only 2 miles upcoast of Broad Beach; however, the point does not provide a similar extent of protection as Lechuza. Decker Canyon draining into the area appears similar to the Steep Hill Canyon entering Lechuza Cove (top). The site supports partially sanded boulder/cobble beds (top middle) and a bedrock headland with both high and low elevation intertidal rock supporting surfgrass (bottom middle). Intertidal resources are similar to those noted within

Lechuza Cove (bottom).

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

El Matador El Matador Beach is a part of the Robert Meyer State Beach and is located approximately 3,400 ft (1,000 m) to the west of the AoPE. The site extends from vertical bluffs on the back beach to -50 ft MLLW. The history of sand flux on El Matador Beach is unknown; however, some of the rock on the beach exhibits indications of scour and burial by sand (including polishing), boulders that lack of persistent biota, and staining. The beach lacks well- developed headlands but rather supports an environment of pinnacle rocks extending vertically to supratidal elevations and a large number of lower relief rocks on an otherwise sandy beach.

The rocks present at El Matador extend across a vertical and size range greater than the boulder field in the AoPE, and thus supports a range of perennial biotic species such as barnacles and mussels. The site also supports sandcastle

worms on the sides of a number of boulders as well as moderately dense and disperse surfgrass.

El Matador was added as a potential reference site at the recommendation of the SAP and regulatory staff to increase pre-project references in order to reduce the risk of inadequate reference sites. The El Matador site serves as a reference for evaluating changes in f classes associated with the rocky intertidal habitat, subtidal habitat, and eelgrass beds. The site is not proposed to be subject to rocky intertidal sampling, subtidal habitat

sampling, nor sampling of the sand beach.

Photo 3-4: El Matador is located close to the western end of Broad Beach. It does not have a defined headland but rather is defined by a scattering of boulders within the intertidal beach and prominent pinnacles (top and top-middle). The rocky habitat includes both non-persistent and persistent invertebrate species, indicative of variable sanding environments (bottom middle). The beach abuts a vertical bluff on the back beach (bottom).

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Zuma East

Zuma East has been identified to serve as a reference area for the sand beach habitat element because of its similarity and proximity to Broad Beach. It has been selected due to its generally similar orientation to Broad Beach, albeit more westerly exposure and less headland protection, and its presence as one of the few persistent sand beaches in the region that has a permanent dry back beach environment. It is located approximately 2.5 miles to the east of Broad Beach, and the coastal exposure aspects and

bathymetry of the nearshore shelf are similar between East Zuma and the AoPE.

The presence of a relatively natural back beach environment makes this site a good candidate for beach sampling in a natural area to compare with the Broad Beach environment. The site has a wide upper beach margin, including a small dune system adjacent to the parking lot.

Detracting from the site as a reference is that the State Park receives a fairly intensive amount of public use on the sandy beach that may adversely affect the faunal communities in the area. However, given the dynamic nature of the habitat and the life history of the target organisms, beach use is not expected to substantively detract from the site conditions. Also, the intensity of disturbance should not change substantively over time. Thus, it can be expected that the human stressor conditions at the site will not alter the site condition in a manner that

results in directional trends.

Photo 3-5: East Zuma Beach has a beach topology similar to Broad Beach and is located approximately 2.5 miles downcoast of Broad Beach (top). The site supports a wide beach (middle) and large back beach that also includes a small dune system (bottom).

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

REFERENCE SITE WEAKNESS AND CORRECTIVE ACTION FRAMEWORK The reference site evaluations and review of available regional and site-specific data yielded several clear realizations of importance to this monitoring program. These include the following:

 There are no perfect reference sites that precisely match Broad Beach from either a physical environment or biological habitat sense. There are several headland and cove sites, but these vary in scale from the AoPE, or vary in nature of the headland, fluvial inputs, characteristics of the hard bottom feature classes, and/or presence or absence of sandy beach environment. Further, there may not be any better reference sites than those selected within the region as the sites identified appear to fit the most factors that parallel observed conditions at Broad Beach.  Available regional monitoring program data provides important baseline conditions and methodology, but does not directly support the monitoring needs of the Project. Regional monitoring data was not specifically designed to examine sand influences on rocky intertidal and subtidal reef habitats and associate species.  Canopy census data from the CRKSC kelp canopy monitoring program illustrates high inter-site variability, but provides a more robust and expansive characterization tool for kelp canopy than could be developed for the Project alone. However, the majority of kelp canopy habitat occur outside of the Project’s projected sand dispersion area, making the kelp canopy metric not well suited for assessing sand impacts on rocky subtidal habitat. The out-of-phase seasonality of beach building within Lechuza Cove (i.e., building during the winter and eroding in the summer) could not be identified as a clear pattern on any other sites within the reference region based on historic photographic analyses. This does not mean such conditions don’t exist, but it creates increased concern regarding suitable reference sites and handling of out-of-phase sand influence results.  Finally, there is inadequate information regarding the dynamics of reference sites to know, a priori, that the reference sites selected are appropriate to a high degree of confidence. At present, the sites can be defined as being the most similar in physical and biological character to the AoPE within the reference region when considering all factors available, including historic photograph review of differing habitat states.

Because of the points above, the SAP and stakeholder agencies have raised concerns over the potential reference sites. While agreement has been reached that the site selection process and reference sites selected are reasonable, a degree of uncertainty remains. For this reason, the SAP has recommended the identification of a framework for addressing weaknesses in relationships between reference sites and the AoPE with respect to variability over time. Specifically, the working assumption is that, while seasonal differences in habitat conditions are expected, habitat conditions at the AoPE should have covarying patterns with those observed at reference sites during baseline conditions such that post-Project deviations in response from reference sites may be used to statistically separate the natural expected patterns over variation from Project- affected response within the AoPE. If the pre-Project baseline lacks robust relationships between sites, the capacity to detect change is undermined and statistical relationships may be weakened to a point of being unusable to support impact analyses.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

SAMPLING METHODS, DATA COLLECTION, AND ANALYSIS

In review, the monitoring objectives for the Plan are as follows:

 Fine scale mapping of the marine feature classes (substrate types, surfgrass, eelgrass, giant kelp cover and wrack) ;  Identification of any adverse impacts to the sandy beach ecosystem resulting from sand nourishment and/or maintenance activities (backpassing, renourishment);  Identification of direct or indirect adverse impacts to subtidal or intertidal habitats resulting from the proposed Project,  Identification of likely causes of any documented adverse impacts (burial, scouring, turbidity, sand grain size, etc.);  Recommendations for adaptive management (e.g., future nourishment sand grain size adjustments, volume of future sand nourishment, sand placement adjustments, seasonal timing and frequency) to avoid continuing adverse impacts, if adverse impacts are detected; and  Inform agency determinations regarding need for compensatory mitigation. MONITORING DURATION AND SAMPLING PERIODS The monitoring program presented in this section describes an integrated and adaptive sampling design constructed to evaluate changes to existing conditions of the diverse habitats and associated species/ functional groups in the AoPE and reference sites by comparing pre- and post-nourishment1 conditions. The monitoring program involves both the fine-scale mapping and field-based quantification of marine habitats and associated species/functional groups based on both standardized and innovative sampling methodologies. The preferred plan for this comparison is to use a Before-After/Control-Impact Paired (BACIP) analysis (Plan A), assuming that at least one of the reference sites will synchronously track the dynamics observed in the AoPE during monitoring, thus enabling a reliable comparison between them over time. The first contingency (Plan B) for assessment would employ the patterns observed across all reference sites to establish an envelope of natural variability in the system. The expectation then becomes that observations from the AoPE should fall within this envelope in the absence of any adverse impact(s). The “best-matching” reference site or sites will be used as the impact threshold. In the event that none of the reference sites are appropriate or catastrophe strikes the reference site(s), the second contingency (Plan C) for assessment then simplifies to comparisons of the post-construction condition in the AoPE with the pre-construction condition. These alternatives will be described in more detail in Section 5. The proposed Project actions may result in pulsed effects to resident biota from the initial sand nourishment, sand backpassing, and supplemental sand nourishment events. The Project may also result in effects of sand bleed to adjacent habitats and biotic components associated with changes in sand grain size. Monitoring under this plan will extend for a period of at least two consecutive sampling seasons (spring and fall) prior to sand placement, and continue over the course of a 10-year period following initial sand placement (Table 4-4). Assuming the initial sand placement activities conclude in early 2018, post-nourishment monitoring would be expected to continue through spring 2028, occurring in the spring and fall of each year to varying extent. The sampling seasons are defined as follows:

 Spring Season. For purposes of sampling under this monitoring program, spring is defined as May 1 through June 30 of any given year. Spring conditions are generally highly variable due to inter-annual differences in severity of winter storm disturbance and timing of recruitment events. As such, the spring sampling time frame has been purposely adjusted to the late spring to reduce the annual variance between spring sampling seasons.

1 Pre-nourishment refers to the period prior to the initial nourishment event, anticipated in fall 2017; post- nourishment refers to the 10-year period thereafter, including any backpassing activities, and subsequent major or minor nourishment events.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

 Fall Season. The fall sampling period is defined as September 1 through November 30 or the first major storm, whichever comes first in any given year. Though large winter storms typically commence in December or early January, an earlier episode could result in significant losses of the kelp canopy and disturbance to sensitive marine resources, including changes to the beach and movement of replenished sand. Seasonally, kelp biomass in California is typically characterized by peaks in summer and autumn, with declines in winter due to wave disturbance (Reed et al. 2008). Sandy beach community diversity and abundance also typically peaks in fall (Revell et al. 2011). Fall sampling, therefore, will allow comparison of the AoPE with reference sites that are likely to be at their ecological peak, maximizing potential differences due to impacts. FEATURE CLASS DISTRIBUTION AND AREAL EXTENT Feature class mapping will be conducted throughout the AoPE and reference sites to capture changes in spatial extent of the various feature classes. Feature class mapping will primarily be conducted using remote- sensing with some integration of field sampling augmenting remote-sensing imagery and information to fill data gaps. Feature class mapping conducted both pre- and post-construction, as well as annually, will therefore be used as a key metric in assessing changes to substrate and biotic community extent in the AoPE as compared to reference sites. Fine-scale feature class mapping will be conducted to identify and quantify the spatial extent of supratidal, intertidal, and subtidal habitat feature classes in the AoPE and reference sites. Feature class mapping will be evaluated in conjunction with in-situ species density and diversity data collected during field surveys to examine and quantify potential adverse impacts to individual habitats and biotic communities resulting from sand nourishment and maintenance activities associated with the Project. The feature class mapping will also provide information on temporal and spatial sand movement patterns in the various habitats to evaluate potential direct and indirect impacts to biological communities attributed to sand burial, scouring, turbidity, and grain size changes. Fine-scale feature class mapping will also provide information for tracking spatial (aerial extent) changes of individual feature classes (e.g., sand, boulder/cobble, Bedrock, eelgrass) and to examine potential adaptive management strategies of future sand nourishment events including sand placement, grain size, seasonal timing, and frequency adjustments. Ultimately, fine-scale feature class mapping will contribute critical metrics to guide the type, extent, and location of any potential mitigation that may be required. INTERTIDAL AND SUPRATIDAL FEATURE CLASS MAPPING Survey Methods –UAV Aerial Photography Mapping surveys of the intertidal and supratidal will extend from above the +10-ft contour that defines the AoPE upper boundary seaward to the lowest tide line and into shallow subtidal waters of the nearshore environment with the goal of overlapping coverage with areas surveyed by acoustic means, as described in Section 4.2.2. Intertidal and supratidal feature classes will be mapped using photography from low altitude UAV flights and, to a lesser extent, during field surveys of some feature classes. Photographs acquired from UAVs will be taken from approximately 20 m above MSL using a dual-mounted camera system consisting of a 16-megapixel digital three‐color‐band camera and a 16-megapixel near infrared (NIR) camera. Flight elevations will be modified based on environmental factors at the time of the flight (e.g., low marine layer) or physical obstructions at target flight elevations. Atmospheric and image normalization will not be performed because each flight will be classified using training polygons from the image. Flight lines will be programmed using photogrammetric flight planning software such that photographs are taken from a motion stabilized camera to provide for 60 percent sidelap and 70 percent forward overlap for consecutive photographs. The resulting native pixel size from the flights will range between 0.32 cm and 0.83 cm.

The collected images will then be processed to orthomosaic photographs using the UAV GPS positional data embedded in the photographs as well as sub-meter GPS ground control points collected as part of the survey. Ground control point locations will include elevations collected at permanent markers established in

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan association with sand beach and rocky intertidal habitat sampling locations. Rocky intertidal ground control points will include the ends of fixed rocky intertidal baseline transects located in the upper and lower intertidal zones of sites established to collect data on species and functional group percent cover information. Additional ground control points will be collected at prominent benchmarks, rocks and other distinct features to provide better vertical and horizontal accuracy measurements. The mosaicking process results in the development of a digital elevation model (DEM) over which the software registers the image data to create an orthogonally‐corrected mosaic image registered to a projected real world coordinate system.

The overall orthomosaic image is spatially accurate to less than 1-ft horizontal position and a similar vertical position when ground‐controlled and developed using multiple flight patterns and elevations. Greater spatial control is possible depending upon the density of control points entered into the software, although for the present application, higher precision has not been explored. Internal to the mosaic image and DEM, the relative spatial accuracy of identified features in all dimensions (x, y, z) is very high and on the order of approximately 3 times pixel size (i.e., ±3 times the pixel edge length) depending upon quality of the imagery, and most explicitly lighting during the tidal flight windows.

The final processed mosaic has a pixel size of 0.72 to 1.48 cm based on composite pixel sizes collected at differing altitudes, process resampling and pixel stretch and loss associated with the orthomosaicing process that spatially registers the image by folding the image over the developed DEM. Orthomosaics are subsequently classified by spectral analyses to separate commonalities in spectral signatures exhibited by the various habitats. Classification is a supervised type wherein the software is trained by selection of multiple examples of features identified visually from the orthomosaic image and assigned to a feature class. These feature class assignments are then used by the processing software to identify shared spectral characteristics across the multiple bands. The software then uses algorithms to classify features into training classes based on best‐fit of the spectral signature. These classified features are then to be aggregated into feature classes. In some instances, it is necessary to bound the raster classification process because of shared signatures between dissimilar and spatially disjunct resources (e.g., some irrigated ornamental landscape plants and ephemeral green algae).

Feature class partitioning will initially be processed for the six feature classes listed below with the primary focus being delineation of substrate types and segregation of biological classes (surfgrass and wrack) that are spatially dispersed. Further spectral classification of biological communities will be explored to delineate the intertidal communities associated with rocky headlands and boulder fields in the AoPE and reference sites. Biological habitat classification of individual intertidal communities (barnacles, mussels, algae) will be evaluated in concert with in-situ sampling to determine if delineation of the community boundaries can be determined in order to better quantify their spatial extent. Processing and delineation of biological zones will utilize site-specific in-situ species/functional group data collected during field surveys, placement of additional ground control points at community boundaries, and spectral data collected through the UAV mapping process.

DEM will aid in separation of sand, cobble/boulder, and bedrock by use of slope residuals; spectral classification will serve to quantify beach wrack and intertidal surfgrass. Habitat feature delineation will be completed by a geographic information systems (GIS) specialist who participated in the UAV flights, ground truth work, and who has expertise in image processing and interpretation. Image processing, spectral classification, and habitat feature mapping will use a suite of software platforms with the final mapping stages performed in ESRI ArcGIS® software. Raw files and interpreted habitat feature class mapping outcomes will be compared to in-situ spatially rectified field sampling data and reviewed for accuracy by a senior biologist on the Project.

Intertidal and Supratidal Feature Classes to be Delineated Substrate habitat feature classes will be identified based on their 2-dimensional surface coverage generated from processing of their spectral definition, location, and feature context. The accuracy of individual feature

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan classes is dependent on the accuracy of classification of the surface features of the substrate or biological resource. As such, classification of feature classes will be limited to six feature classes feature (see below) best suited for the UAV mapping application. These classifications will be restricted to a level where mapping yields error rates of less than 10 percent misclassification based on unbiased ground‐truthing analyses. For intertidal and supratidal habitat mapping the following six feature classes will be distinguished:

 Rip Rap Revetment  Bedrock  Boulder/Cobble  Sand  Wrack  Surfgrass Image Classification Process Initial image classification will be a semi-automated classification process performed in ArcGIS® using the image classification toolbar. Input will consist of a four-band NIR image plus a slope residual dataset. The slope residual dataset will be processed from the elevation surface output from the UAV flight data. Training areas will be created with the support of a field biologist familiar with the sites. The image classification algorithm uses the composition of spectra (pixel values) within the training area to classify the rest of the image to the feature class with similar pixel values.

The initial classification process will be reviewed by a biologist to identify and correct any misclassification. It is anticipated that feature classes with similar color surface texture will have to be reclassified based on location and context of the area. Surfgrass can be basally sanded and will not be used to define a rock feature class, but will be treated as its own feature class with the degree of sanding part of the characteristics of the surfgrass feature class. This semi-automated image classification using spectral methods for substrate mapping provides a more accurate means of mapping, within a complex habitat mosaic, compared to polygon mapping. Specifically, raster classification tools allow for more precise separation of features than polygon mapping methods, improving the accuracy of the spatial extent of individual feature classes.

Limitations of aerial photographic mapping methods include discerning feature classes in whitewash of the surf zone, areas of high turbidity, deep water where the bottom is not visible, or in areas of glare, deep shadows, or other locations where portions of the photomosaic show information content present which is inadequate for feature classifications. As a result, areas below the lowest tide levels or inundated with water will be mapped or coded as “water/unclassifiable.” In general, this unclassifiable element is most extensive along the sandy beach of the AoPE where sand is the dominant feature class and resources should be adequately quantified by conventional sampling methods. Submerged and over-wash areas associated with boulder/cobble, low lying bedrock, and surfgrass are the most problematic and will be mapped using an amalgamation of both UAV mapping to identify the shoreward margin of the feature class and field surveys to map the seaward margin. Overall areas not suitably mapped from aerial imagery alone will be classified by GIS specialists and biologists utilizing a combination of field verification and image analysis tools described in Section 4.2.3, Managing Habitat Mapping Gaps. These areas will be reclassed post-accuracy assessment scoring so the accuracy score will not be inflated. Any areas not addressed will remain classified as water/unclassifiable and will be excluded from the analysis.

Intertidal Feature Class Mapping Accuracy - Ground Truthing The image classification effort generates a 2-dimensional spatial extent of feature classes. The accuracy of the feature class mapping will be determined by two separate field ground truthing methods in order to validate the overall trend in feature class extent for the study areas. Initially ground truthing will be performed by randomly selecting 100 review points of each mapping site prior to individual site surveys.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

These points will be evaluated independently by a biologist on-site using a sub-meter GPS unit. The review points will be randomly selected but stratified by each feature class to guarantee at least ten points per class type. Given that the rip rap revetment is a static and spatially distinct feature, it will be excluded from the ground truthing during the preconstruction mapping efforts. First, ten random points will be generated for each feature class based on aerial imagery or previous mapping in the area. The remaining 40 points will be randomly placed using the entire study site. Note, these review points will not be drawn from areas that were used in the image classification process or that were classified based on field data. Random points will be generated using the Create Random Points tool available from the ESRI ArcGIS® Data Management Toolbox. Results of the ground truth points will be evaluated to measure accuracy of the image classification method for each site to establish a site error and composited for all sites to examine a sampling error for image classification of the feature classes.

To additionally evaluate the accuracy of image classification of the feature classes and the potential to map intertidal functional groups, the in-situ intertidal monitoring data will be used as an additional level of ground truthing. As part of the modified biodiversity approach proposed to identify and quantify species and functional groups within the intertidal, 1000 Uniform Point Counts (UPCs) will be collected throughout each rocky intertidal site from the upper to lower intertidal zones. At each point, the species or functional group as well as the substrate is recorded. Baseline transects are permanently marked with bolts or epoxy from which 10 vertical transects placed at least 3 m apart in parallel orientation are placed creating a grid. The transects are mapped using a sub-meter GPS to match the sampling area and provide a geo-referenced frame work in which the image classification results can be compared. Within each functional group, 100 UPC points will be selected to evaluate the accuracy of feature classification and functional group classifications generated from the spectral algorithms. Adjustments to the spectral classification methodology will be conducted with the intent to achieve a level of accuracy that exceeds 95 percent in order to reduce ground truthing for future survey years, if warranted.

Schedule and Frequency Intertidal and supratidal feature class mapping will be completed annually (placement) during the spring and fall prior to sand nourishment and each year in the fall following sand nourishment in conjunction with field sampling. Pre‐ nourishment baseline habitat mapping data will be derived from a minimum of three survey intervals (fall 2016, spring 2017, and fall 2017). Surveys post‐ nourishment will be continued in the fall of each subsequent year following sand nourishment, for a total of 10 years of data collection following initial sand nourishment.

Subtidal Feature Class Mapping Survey Methods - Multibeam Sonar Acoustic surveys will be conducted by eTrac Inc. to map subtidal benthic feature classes in the AoPE and reference sites. eTrac Inc. is a California-based firm that provides hydrographic survey data acquisition and processing services. Its staff of certified hydrographers and licensed land surveyors have a long history performing high accuracy sonar and LiDAR surveys in all types of marine environments. Acoustic surveys will be conducted by eTrac using a multibeam echo sounder (MBES) system operating in the 400-700kHz range generating a high resolution, geo-referenced point cloud. The data obtained by the MBES unit provides both bathymetric point cloud and acoustic backscatter intensity data with each ping. The resulting data points will then be used to develop bathymetric contours, feature class extent, and relative density of biological communities. The MBES system would be attached to the vessel using a rigid over-the-side mounting system, similar to the systems and methods utilized during the previous survey events. Sensors are measured in relation to one another with millimeter accuracy using an optical instrument while the vessel is on its trailer on land. During water-based operations, the vessel’s position and orientation is measured by an inertial measurement system that generates centimeter-accurate results at a rate of 200 times per second. A local GPS base station is deployed prior to the acquisition of data. GPS corrections are applied using this static GPS base to correct for real-time positional ambiguities during

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan sonar data acquisition. Post-processing of the inertial and sonar data further refines the accuracies of the final MBES dataset. The resultant point cloud will be in the 2-5 cm accuracy range. Acoustic survey data will be reviewed and feature class spatial extent (area) calculated for each individual feature class in the AoPE and reference sites. Final coverage data will be reviewed through an internal QA/QC review process. Real-time and post-processed standard deviation plots will be generated using overlapping sonar swath data. Highlighting higher standard deviations in grid cells over the Project area in a color-coded manner allows data processors and reviewers to quickly identify inconsistencies in the data. Data not meeting required data quality standards can quickly be identified, clipped out and/or corrected. The data will be transferred to an ArcGIS® coverage and habitat delineated and plotted on a geo-rectified aerial image of the survey sites. Bathymetric data will be used to calculate the change in sand deposition and erosion within the AoPE and reference sites. High-density depth grids are created for each sonar acquisition event from the final processed datasets. Depths grids are compared using a “delta grid” which uses a color scale to highlight depth changes in areas across the site. Changes in horizontal relief of sand are immediately evident with varying shades of red (marked as erosion) and blue (deposition). These graphics facilitate the evaluation of sand distribution and aid in the interpretation of Project-related impacts to subtidal habitats. While surf and swell conditions within nearshore environments are the harshest and most difficult environment in which to complete bathymetric surveys, the sensor systems are able to maintain high accuracy in dynamic environments such as the near-beach environment. Additional sonar survey passes are performed through areas with a high likelihood of data gaps, lower accuracy, bubble injection in the water column from crashing waves or high currents, highly dynamic vessel pitching and rolling, etc. Localized artifacts and errors in bathymetry can easily be interpreted using the color-coding standard deviation plots described in the QA/QC methods above. Multiple information sources from multiple passes of the survey vessel through complex areas results in robust results as spurious data from each can be compared in relation to one another in the 3- dimensional visualization and analysis mode of post-processing. Low quality, spurious data are identified and rejected in favor of the higher quality data agreeing with overlapping passes.

Following field data collection, the digital sonar traces (backscatter data) are processed into a single rectified mosaic image. As the backscatter imagery is georeferenced in real-time by way of being acquired from a fixed-mounted multibeam system, the positional ambiguities of a traditional towed side-scan sonar towfish are removed. The registered sonar mosaic has a positional accuracy equal to that of the multibeam bathymetry data (i.e., 2-5 cm in most cases). The mosaic files are overlaid on aerial images of the survey area and reviewed for alignment accuracy. Bathymetric data are processed using manual editing and by applying statistical filtering (i.e., spline filters) and are used to develop slope and relief maps to facilitate feature class mapping rather than being used as a direct assessment tool.

Sonar maps will be analyzed for percentage coverage of specific bottom type and vegetation identification. Analysis and visualization for this type interpretation employs the use of a larger grid (i.e., 5-ft cell spacing vs. the typical 0.5-1.0 grid spacing of the full resolution dataset). By color-coding the grid and analyzing with relation to normalized backscatter as well as bathymetric relief, eelgrass coverage percentage can be defined in terms of varying degrees of cover and no cover. Substrate feature classes are delineated and identified using Fledermaus Frequency Modulation Geocoder Toolbox software which handles the backscatter datasets in a rich 3-dimensional environment.

Methods will be put in place during data acquisition that will facilitate ground-truthing of sonar response to various substrate feature classes. Sediment samples and video of the area will be used to relate the MBES survey results to actual physical data.

Surficial features and mappable benthic feature classes are then digitized by a GIS specialist with expertise in interpreting sonar data for feature class mapping. Edge definition will be aided by object recognition segmentation analyses that use edge detection and pattern recognition to develop polygons based on raster interpretation. These polygons are then collapsed manually during interpretation into defined feature classes. As with the raster interpretation tools discussed for UAV surveys, this method results in maintenance of

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan minimum mapping units based on the raster data. The GIS specialist will inspect the sonar mosaic and delineate feature classes using ESRI ArcGIS® software. Raw files and interpreted mosaics are reviewed for accuracy by an experienced senior biologist on the Project.

Subtidal Feature Classes to be Delineated The accuracy of feature classification is resource-specific, but based on previous surveys and specific visual and physical verifications conducted on numerous Corps and NOAA projects, error rates are less than 1 percent with respect to substrate feature classification. Mapping and quantification of eelgrass habitat extent has a slightly higher error rate due to overestimation of eelgrass due to epiphytes and associated invertebrate assemblages colonizing adjacent sand habitat. As such, classification of feature classes will assess error rates of each feature class based on visual ground-truth observations collected during subtidal sampling of rocky reef, surfgrass, eelgrass, and subtidal sand habitat field data collections. While biotic features on hard substrate such as kelp, subcanopy algae and surfgrass can sometimes be interpreted from sidescan mosaics, the monochromatic nature of the backscatter data along with high reflectance of underlying rock makes such interpretations prone to inaccuracies under many circumstances. As such, feature class mapping within the subtidal is proposed to be limited to the following feature classes:

 Bedrock  Eelgrass  Boulder/Cobble  Sand

During initial pilot studies, close review of sidescan data as well as camera data resulted in a determination that scattered sand dollars on the sand bottom and kelp on reefs were not mappable resources with a high degree of accuracy. Pismo clams do not occur at any appreciable density in the area and are not mappable as a feature class even when present; thus, they were not included in the subtidal feature class mapping element. Coarse gravel channels extending outward from the surf zone are highly visible but are considered transient energy features of sand and, thus, not proposed to be mapped as a distinct feature class.

The extent of mapping will be determined by physical survey constraints and safety limitations during each survey period. In general, acoustic mapping will cover all areas of the AoPE extending inshore to a depth beyond which it is unsafe to continue, or beyond which no useful data is being collected. In general, the survey vessel will not travel into the outer limit of breakers, exposed coast depths shallower than 8 ft. below the transducer, areas with tightly spaced boulders that limit surf escape options, or areas where breaking waves have entrained too much air in the water to allow for effective sonar survey. During high tides and flat surf conditions, it is generally possible to survey close enough to the beach to obtain overlap between low tide UAV surveys and high tide acoustic surveys. However, there may be gaps between the beach survey data and the subtidal survey data in what is typically considered the surf zone. The approach for addressing/analyzing these gaps is addressed in Section 4.2.3, Managing Habitat Mapping Gaps.

Accuracy Ground-truthing via Habitat-specific Surveys Ground-truthing will be performed to assess acoustic mapping accuracy. The results of the ground-truthing will be used to establish confidence limits around the quantified extent of the mapped feature classes. For the feature classes acoustically mapped, random points will be selected from multiple transects from each site and field sampling methods used to examine differences in feature classification. To ground-truth subtidal feature classes of bedrock, boulder/cobble, and sand habitat within the subtidal, the subtidal rocky reef transects will be utilized to sample 100 points spatially distributed at distinct whole meter marks (e.g., 1.0, 2.0, 7.0) located among the 12 separate transects (see Figure 4-3).

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

While it is likely that boulder/cobble habitat will be underrepresented in terms of the ground-truthing method, it is also highly likely that little boulder/cobble habitat exists outside of the beach, intertidal and surfzone based on the wave climate typical of this exposed coast. Considering the limited extent of the boulder/cobble feature class in the subtidal rock reef habitat and its transient nature pending sand deposition/erosion, ground-truthing of the boulder/cobble feature class will likely lack statistical rigor. However, considering that the boulder/cobble habitat is a fractional component of the subtidal rocky reef habitat and is not documented to support different or diverse biotic assemblages likely to be effected by sand inundation no additional methodology is proposed to further calibrate changes in the boulder/cobble feature class in the subtidal.

For ground-truthing of eelgrass habitat, a counterweighted line and buoy will be placed approximately 10 m outside the edge of three separately mapped eelgrass beds at each site and 100-m transects run inshore over a defined compass heading. At the end of each transect a pelican buoy will be released to mark the end, and both buoy locations of each transect will be recorded using a hand held sub-meter GPS. At 5 m increments (e.g., 0, 5, 10,.., 25 m), point intercepts will be recorded for substrate and a 4 m2 area centered on the meter mark recorded for percent cover of eelgrass (0, 25%, 50%,

75%, and 100%). A total of 100 points will be collected at the Photo 4-1: Ground-truth points from drop- AoPE and each reference site to visually verify eelgrass habitat camera. Point confirms habitat feature and percent cover. The buoy locations will then be imported into substrate for bedrock, boulder/cobble, eelgrass, and sand habitats. ArcGIS® and the data sets compared to evaluate error associated with the eelgrass feature class. Error rates will be reported during each of the sampling events.

Schedule and Frequency Acoustic surveys will be completed prior to sand nourishment during the spring and fall and following sand nourishment each year in the fall prior to field sampling. Pre-impact subtidal acoustic habitat mapping data will be derived from a minimum of three survey intervals prior to the initial sand placement (fall 2016, spring 2017, and fall 2017). The fall 2016 data has been acoustically collected in a manner similar to that described above, but the fall 2016 ground-truthing method utilized drop cameras and remotely operated vehicles rather than visual verification by scientific divers. Differences in feature class spatial extent affected by changes in the ground-truthing methods are not expected to eclipse seasonal variability; thus, averaging feature class spatial extent is not likely to affect calculated baseline conditions within the AoPE. No specific comparison ground-truthing methods will be analyzed but rather error rates for fall mapping efforts will be examined for consistency. Mapping surveys will continue in the fall of each year, for a total of 10 years of data collection following initial sand placement. Mapping and field sampling frequency for each habitat category are shown in Table 4-4. Managing Feature Class Mapping Gaps The capacity to collect mapping data within the surf zone with either UAV or sonar acoustic methods is limited and variable based upon a number of factors, including water clarity, air entrainment, sea foam extent, and safety considerations. As a result, it is not expected to be uncommon for small (10-30 m wide) unmapped zones to exist between the UAV and sonar mapping extents (Figure 4-4). At times, this zone will be completed by overlay between methods while at other times, a gap will exist in the known extent of

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan feature classes. Variation in gap size will influence the extent of mapped feature classes at all sites (AoPE and reference sites). However, the scale of the gap is not predictably proportional between sites. For this reason, managing feature class data within the survey gap is important to the overall change analyses.

The distribution of the various feature classes represented in the AoPE (Figure 2-3) is predominantly sand with the feature classes of concern (e.g., bedrock, boulder/cobble, surfgrass) relatively confined to the western portion of the AoPE and shoreward of -15 ft MLLW. Similar conditions exist at the reference sites with feature class data gaps occurring most frequently in rocky intertidal and subtidal areas adjacent to rock headlands or occupied by dense kelp forests. Considering the extent and diversity of feature classes in the western portion of the AoPE and at concentrated locations of reference sites, gap analysis will be conducted using a combination of both ArcGIS® interpolation and site specific ground-truthing to fill in the gaps.

Spatial data gaps can be filled by a combination of two methods, including the following:

 Interpolated Gap Fill - The distribution of feature classes within a gap may be interpolated from the feature class on either side of the gap based on the results of each survey. The interpolated feature class approach would have greatest appeal where habitat features are consistent from the intertidal to the surveyable subtidal. However, the feature classes of concern (rock, boulder/cobble, and surfgrass) are often located in a zone of transition (surfzone) and the documented feature class along the shore do not consistently or predictably extend to the shallow subtidal. As such, inference would need to follow standardized rules regarding presumed feature class breaks. For each survey, it can be assumed that the mapped feature class extends one-half the distances across the unmappable gap at a width equivalent to the width at the point where the feature class becomes unmappable. In the case where the same feature class is mapped on either side of the gap, that specific feature class progressively fills the gap until feature classes are inconsistent between mapped areas. This method would be most effective in addressing gaps associated with sand and would have the least effect on skewing the impact analysis. For gaps less than 10 m and 10 m along shore with different feature classes on either side, the gap will be filled with the representational feature class for each side. For gaps greater than 10 m wide and/or 10 m along shore with sand on both sides, the entire gap will be classified as sand. For gaps greater than 10 m wide with differing feature classes on each side, field mapping will be applied. Based on the large spatial extent of the AoPE and reference sites the 10 m distance was selected as the standard unit of gap review to facilitate partitioning while not overly impacting the assessment of feature class spatial extent.  Field Mapping - Considering the limited mechanisms available for mapping subtidal substrate feature classes within the surf zone, field based survey methods will be implemented to collect representative cross sections within feature class mapping gaps located within the rock, boulder/cobble, and surfgrass feature class. For each of these feature classes, their spatial extent will most effectively be delineated within the intertidal region (shoreward of -1.0 ft MLLW) through the use of UAV imagery. Seaward of -1.0 ft MLLW, a combination of wading and snorkeling transects will be conducted to identify feature classes. The field mapping will be conducted by two individuals working from the beach using a base map housed on an electronic tablet and field survey equipment. The base map will have a composite orthomosaic of the feature classes delineated from the UAV and subtidal acoustic mapping imagery, the associated gap, and evenly spaced pre-populated transects (no greater than 10 m apart). Three consecutive transects will be surveyed for each gap area of 50 m of shoreline to obtain a representational quantification of feature classes within each area of shoreline. Each transect will originate from shore moving into the surf zone with a biologist outfitted with a wetsuit, 50 m reel tape, custom slate, and submersible very high frequency (VHF) radio. The shore-based recorder will use the electronic base maps and laser outfitted sub-meter GPS to record changes in feature class. Wading or snorkeling, the biologist will progressively map feature classes away from shore below the -1.0 ft MLLW mark trailing the meter tape. The biologist will signal changes in

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feature class to the shore-based recorder using the VHF radio or by raising the slate in the air. The shore-based recorder will use the laser GPS to ping the slate obtaining a sub-meter GPS location. The substrate type will be communicated over the VHF radio or alternately through a combination of hand signals and slate configuration. Feature classes will be mapped to 2 m on either side of the line for rock and 1 m for surfgrass or boulder/cobble. Interpolated gap fill criteria described above will be applied to populate the feature classes between field map transects to create a fully populated feature class extent of sites. HABITAT SAMPLING Habitat sampling is the measurement of physical and biological factors that characterize specific habitat types, coastal marine habitats in this instance. Habitat sampling for monitoring purposes typically targets physical features and species and/or functional groups identified as elements of the respective habitats that have the potential to be adversely impacted by specific activities or projects. Here, habitat sampling entails measurement of physical and biological attributes of the supratidal, intertidal, and subtidal habitats found in and near the Broad Beach project footprint using methods designed to evaluate changes in these habitats through time. The habitat sampling methods presented in this section mostly follow classic marine field sampling methods and techniques that have been used across the west coast of the U.S. and elsewhere for decades and, most recently, for the establishment and monitoring of MPAs. The individual habitat sampling methods presented below are designed to target physical and biological habitat attributes important for evaluating habitat status, health, and function in order to track temporal and spatial change. Collectively, habitat mapping and sampling will be integrated to evaluate changes in spatial extent and condition of the respective marine habitats through time.

The placement of habitat sampling locations in the AoPE was determined based on several criteria: 1) proximity to sand placement site; 2) areas modeled to incur sand deposition over a 6-month and 1-year time frame; 3) suitable habitat extent for permanent transect establishment; and 4) distribution of transects throughout representative habitat. In terms of the AoPE, much of the hard substrate habitat and associated biotic communities are located in the western portion of the AoPE. Hard substrate within the surf zone and shallow subtidal (<15 ft MLLW) is subject to seasonal sand deposition/erosion and occurs as primarily small outcroppings of 1-3 m2, not suitable for long-term monitoring to assess sanding impacts. The rock extent depicted in maps is a composite of previously mapped substrate displaying the maximum extent of rock or boulder/cobble habitat. The hard substrate in the shallow subtidal is nearly continuously exposed and buried on monthly or even weekly time frames. The placement of individual habitat sampling transects took into account the ability to conduct accurate repeated sampling, access to sampling areas (depth), targeted biotic communities, and measurable vertical surfaces to track sand deposition/erosion. Figure 4-1 displays the habitat sampling locations and individual transects for the various sampling methods in the AoPE in conjunction with the projected 6-month sand deposition developed from modeling. Figure 4-2 displays the same locations and transects with the projected 1-year sand deposition indicated by modeling results. Later sections discuss subtidal habitat sampling display maps that show subtidal transects determined using identical criteria. It should be noted that the model results compared with natural seasonal accumulation does not extend any further than the most westernmost profile survey transect and thus does not cover the far western portion of Lechuza Cove, but sand deposition is expected to follow a similar trajectory of a lesser magnitude, as displayed in the maps.

Sampling design for this project has been guided by statistical power analyses following the 20-20-20 guideline. Statistical power analysis uses the relationships among the four variables involved in statistical inference: sample size (N), significance criterion (α), effect size (ES), and statistical power. For any statistical model, each of these variables is a function of the other three. For research planning we can estimate the N necessary to have a specified power for given α and ES. To do that we need to specify α, power (1-β), effect size, and the population variability (standard deviation of the mean). The 20-20-20 concept is an attempt to balance our ability to detect an effect on an ecosystem, in this case an impact due to beach replenishment, with the inherent variability associated with ecological systems. The numbers 20-20-20

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan refer to the parameters required to execute a power analysis that can be used to guide sampling. The 20’s are probabilities of Type I and II errors (20% each) and the effect size (20% change in a given response variable).

Essentially, a “Type I” error can be thought of as concluding there is an effect that is not present, while a “Type II” error is the failure to detect an effect that is present. In this case, committing a Type I error means concluding that there is an impact that that does not exist, i.e. it is due to natural variability, poor sampling or inappropriate sampling design, while committing a Type II error means failing to detect an actual ecological impact caused by sand replenishment. A Type I error would incur unwarranted costs to the project (e.g. by unwarranted mitigation), while a Type II error would shortchange the public interest by allowing impacts to ecosystem services to go unmitigated. The probabilities of committing a Type I or Type II error are usually referred to as α and β respectively, and decreasing the probability of one of them may substantially increase the probability of the other.

In scientific studies, the typical approach is to minimize the probability of Type I error, in order to minimize the reporting of positive results that are not meaningful or valid. Requiring such low rates of Type I error (e.g., α = 0.05) means that equivalent probability of Type II error can occur only when effect sizes (ES) are very large or when very many samples are taken. In ecological impact studies, in contrast, it has often been recommended that the public interest be given more weight, and that the probability of committing a Type II error therefore be given equal weight. Therefore, a balanced approach equalizes α and β, often at values >0.05.

The designation for detectable effect size is underlain by the inherent variability in dynamic ecosystems, which means that detecting small changes requires very large and often logistically impossible levels of sampling effort. There is no conventional standard for setting effect size, and it is typically considered a matter of common sense or judgement on what level of change is ecologically significant or managerially acceptable (Mapstone 1995, Legg and Nagy 2006). The 20% level is consistent with effects of produced water impacts on California coastal ecosystems, which were larger than 20% on average at sites far from the discharge, and more than twice that level at sites near the discharge (Osenberg et al 1994).

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Figure 4-1: Habitat Sampling Locations and Transects in the AoPE with 6-month Sand Transport Model

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Figure 4-2: Habitat Sampling Locations and Transects in the AoPE with 1-year Sand Transport Model

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Intertidal Habitat Sampling Rocky Intertidal Sampling Rocky intertidal habitat sampling will be conducted using a modified Coastal Biodiversity Survey Protocol (Biodiversity survey) targeting representative species and functional groups within the rocky intertidal. The sampling will include UPCs, marcoinvertebrate swath counts, motile invertebrate quadrats, and vertical surface surveys. The modified approach is based on Biodiversity survey methods developed by the UCSC that have been conducted throughout California, for South Coast Region MPAs, and at ASBS locations (Mugu Lagoon to Latigo Point ASBS), including both Lechuza Point and Sequit Point (accessed online http://www.eeb.ucsc.edu/pacificrockyintertidal/sitepages/lechuzapoint.html).

Rocky intertidal sampling will be conducted at Lechuza Point (AoPE) and two reference sites: Sequit Point/Leo Carrillo and El Pescador. Survey locations were established following site criteria defined in the Biodiversity survey methods to the extent possible, with some exceptions. Survey sites were established on a bedrock intertidal bench and adjacent boulder/cobble field from the high to low zone and located to capture a representative sample of the intertidal community of each site. In all cases, the sites required the areas be split between two adjacent locations, each of the two locations were similar in width and length to the maximum extent possible.

Setup of each of the rocky intertidal monitoring sites involved placement of a series of parallel transects extending from the high zone to the low zone. The upper limit of the site was defined by a 15 to 30-m baseline parallel to shore in the case of the rocky benches, and along an elevated ridge in the case of the boulder fields above or near the upper limit of the organism. A second 15 to 30-m lower baseline established in the mid to low zone parallel to the upper baseline. The four corners of each site defined by the intersection of the baselines and outer transects will be permanently marked with carriage bolts embedded in the rock and epoxied in place. Following placement of the initial parallel baselines, no fewer than five transects are monitored no less than every 3 meters along the upper baseline and continue through the corresponding meter number at the lower baseline. Each sampling site was Photo 4-2: Biodiversity sampling targets functional groups established to have 10 transects with 5 placed in the rocky used in the assessment of intertidal habitat change. The bench and 5 in the boulder/cobble habitat. For the AoPE, an Biodiversity survey protocol includes UPCs, swath surveys additional 5 transects were placed in the boulder field and motile invertebrate quadrat counts along multiple transects to allow comparisons with historic sampling located on the beach near the western edge of the sand events that displayed adequate statistical power to assess placement area. Power analysis conducted on the spring changes in intertidal communities. 2017 sampling and on long-term MARINe/SWAT data provided by Dr. Pete Raimondi has shown that 6 transects is sufficient to detect a 20% effect size on targeted functional groups at alpha () and beta () of 0.2 (20-20-20 rule). The 20-20-20 rule is where Type I error (the null hypothesis is true but rejected) or  is set at 0.20, Type II error (the null hypothesis is false but accepted) or  is set at 0.20, and power is equal to 1- or 0.80. Initially all the intertidal transects for a site were anticipated to be evaluated together (10 transects) to examine changes in species and/or functional

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan groups but bench and boulder/cobble transect data collected and evaluated from the spring 2017 sampling displayed notable differences in biotic components between the areas. Based on that analysis rocky intertidal sites will now be evaluated as two separate areas (bench vs boulder/cobble) and an additional transect will be added to each set of transects to achieve sufficient power to meet the 20-20-20 rule, for the sessile invertebrate and combined algae broad functional groups. Functional group/species variability within sites and between sites confounded by the limited spatial extent of features (substrates) that support the functional groups/species requires adaptive management of the monitoring program. Species specific data will be collected during monitoring and presented to regulatory agencies annually for assessment as well as analyzed for inclusion of the annual reports, regardless of whether individual functional group/species data meets the 20-20-20 rule parameters for sampling design considerations.

The GPS coordinates of the site bolts and intersection at the lower baseline were recorded using a Trimble GEO 7X GPS and photographs of the site will be taken during each visit. The distance and bearing between the baseline end bolts will be measured and a compass heading of the vertical transects, coastal orientation, and the sampling interval will be recorded. Additional transect lines to monitor sand encroachment on vertical rocky habitat were established at 20 locations at each site. These vertical surface transects were located along the upcoast and downcoast margins of the rocky bench or in obvious wash channels that transect the site and support intertidal communities subject to sand impacts. The horizontal transects serve to increase point counts of the vertical surfaces most subject to sand inundation and scour. Marking of the transects and measurement of vertical surfaces is further discussed below. Rocky intertidal habitat sampling will be completed prior to sand nourishment (placement) during the spring and fall and following sand nourishment each year in the fall prior to field sampling (Table 4-4).

Point-Contact Surveys

Vertical transects will be sampled using the point intercept method sampling from the upper zone down to the water’s edge at low tide. One hundred points will be sampled on each transect line with the interval subject to the length of transects. For each point contact, the functional group or representative species will be identified with only the primary (attached) space occupant scored (Table 4-1). The method enables determination of the relative abundance (% cover) of algae and invertebrates along each transect and collectively throughout individual sites. Functional groups and species were selected based on their inclusion in PISCO or MARINe regional monitoring programs and to facilitate comparisons with historic regional data sets collected at the AoPE and reference sites. The species and/or functional groups monitored in UPC’s are inclusive of all possible sessile species potentially encountered during sampling but were grouped to simplify the impact assessment, improve power, and for the fact that sand impacts are not species specific. For each point the substrate (rock, cobble, sand) will also be recorded. Layering will not be recorded.

Table 4-1: Functional Group and Representative Species Scored during Point Contact Surveys for Rocky Intertidal Sampling using Modified Biodiversity Approach

Functional Group Species Anemone Anthopleura elegantissima/sola Acorn Barnacle Balanus/Cthamalus spp. Tetraclita Tetraclita rubescens Gooseneck Barnacle Pollicipes polymerus Mussel Mytilus californianus Phragmatapoma Phragmatopoma californica Fucoid Algae All other Fucoid Algae Species not Listed Below Silvetia Silvetia compressa Fucus Fucus distichus

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Hesperophycus Hesperophycus harveyanus Brown Algae All other Brown Algae Species not Listed Below Egregia Egregia menziesii Green Algae All other Green Algae Species Red Algae All other Red Algae Species not Listed Below Endocladia Endocladia muricata Encrusted Coralline Algae All other Encrusted Coralline Algae Species Articulated Coralline Algae All other Articulated Coralline Algae Species Surfgrass Phyllospadix spp. Miscellaneous Invertebrate Serpulorbus spp., Limpets, etc Bare Rock, Boulder, Cobble or Sand Surface with no Biotic Cover

Mobile Invertebrate Quadrat Surveys

To account for motile invertebrate species not quantified in point-contact surveys, motile invertebrates (e.g., limpets, snails, chitons) will be evaluate using 50 x 50 cm quadrats placed at three locations along each transect, consistent with the Biodiversity survey protocol. Each transect is first divided into three zones; the low zone is the area below the mussels, the mid-zone includes mussels and fucoid alga (e.g. Silvetia, Pelvetiopsis), and the high zone is the area dominated by barnacles and littorines. Within each zone, a quadrat will be randomly placed on transects and all mobile species found within the quadrat will be identified to broad functional groups and counted (Table 4-2). The use of broad functional groups versus individual species identification provides increased efficiency in sampling while maintaining the ability to evaluate motile invertebrate densities and diversity in relationship to Biodiversity survey data collected in 2009 and 2013 at Lechuza Point and the reference sites. A random number generator will provide numbers that correspond to locations (in meters) along a transect line where the quadrat will be placed. Sub-sampling will be used when more than 100 individuals of a functional group is enumerated in any one quadrat. If the location of a quadrat is in a deep pool, a new location will be selected. The only motile species that will not be counted are worms, Neomolgus littoralis (red mites), and amphipods.

Table 4-2: List of Motile Invertebrate Functional Groups Counted in Motile Invertebrate Quadrat Surveys Phylum Class Functional Group Species Arthropoda Decapoda Crabs Isopods Mollusca Gastropoda Limpets All Limpets on List Below Lottia Gigantia (> 25 mm) Snails All Snails not on List Below Littorina spp. Tegula spp. Whelks (Nucella/Acanthina) Sea Slugs Polyplacophora Chitons Nudibranch Echinodermata Asteroidea Sea stars Echinoidea Sea urchins Holothuroidea Cucumbers Chordata Fish *Functional grounds indicated in bold. Swath Counts Surveys

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Some motile invertebrates can be clustered or spatially uncommon, thus a greater search area is required to quantify their abundance. The abundance of three functional groups or species of macroinvertebrates (sea stars, abalone, owl limpet [Lottia gigantea]) will be measured along a 2-m swath along each vertical transect. The location and abundance of these motile macroinvertebrates along each transect (to the nearest 0.5 m) will be recorded as well as abundance. All sea stars measuring greater than 5 cm in total length will be counted and identified to species. All Owl limpets measuring greater than 25 mm in total length will be counted. All abalone will be identified to species, measured, and photographed. NMFS will be notified of any protected species observed during surveys (e.g., abalone).

Vertical Surfaces

To examine the extent of sand deposition or erosion at individual locations within the rocky intertidal and boulder fields sampled at the AoPE and reference sites, hex bolts or epoxy markers will be established at vertical surface sampling locations. The bolts or markers will serve as benchmarks to measure the relative change in sand height at three locations along short vertical surface transects placed along the surfaces adjacent to the markers. Measurements will be collected at a minimum of 20 locations at each site between the 2.0 and -2.0 ft MLLW tide mark near the edge of wash channels, margins of the rocky bench, and in boulder fields. The three measurements associated with each bolt will be collected at the nearest location to the bolt at which the bottom channel or margin can be confirmed and two additional locations Photo 4-3: Vertical surface on bedrock outcrop showing (spaced at least 0.5 m from each other) along the trajectory lower margin of the rock surface supporting crustose coralline surface to be targeted in vertical surface of the vertical surface transect. The distance measurement monitoring within the rocky intertidal. will be a snapped (tight) meter tape measurement from the bolt/marker to the bottom of the base of the channel or margin. The establishment of the vertical surface sampling locations will be placed to avoid obstructions (rock outcroppings or boulders) that interfere with implementing a taught measurement. The same locations will be measured during each survey event with the bottom substrate (rock, cobble, sand) and distance from the bolt to the bottom channel or margin recorded for each measurement. The distance from the bolt to the bottom will be recorded in 0.1-m intervals.

In conjunction with the physical measurements of the vertical surfaces, point contact surveys will be conducted at each of the 20 vertical surface locations from the bolt or marker to the base of the channel, bench or boulder. The short vertical surface transects will collect point counts of primary cover sessile species attached to the substrate every 0.1 m, or at an interval sufficient to collect 10 points at each vertical transect. Primary species identified and recorded will be the same as those enumerated in the other point count surveys described previously (see Table 4-1).

Surfgrass Sampling Given that surfgrass areal extent can only partially be determined through UAV and acoustic sonar mapping, in-situ sampling methods are critical to quantify regional trends, as well as site-specific conditions within the AoPE and reference sites. The two species of surfgrass, Phyllospadix torreyi and Phylospadix scouleri, are bathymetrically differentiated when co-occurring with P. torreyi growing deeper than P. scouleri (Phillips 1979). The upper limit of surfgrass distribution is approximately 0.3 m below MLLW with P. scouleri occupying shallower zones and P. torreyi extending to approximately 4 m below MLLW (Garcia et al. 1998). The concentration of surfgrass within the low intertidal and shallow subtidal (surf zone) requires that sampling be conducted at negative tides to quantify the greatest extent of surfgrass habitat. The ability to quantify surfgrass seaward habitat extent, other than spatial extent mapping, is not currently feasible, and

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan adaptive solutions will continue to be evaluated and presented to regulatory agencies for review. Surfgrass grows nearly exclusively in wave-swept shallow rocky habitat; currently there are no standardized methods for assessing the extent of surfgrass beyond the negative tide extent. Sampling strategies typically employed in regional monitoring programs, such as MARINe and Biodiversity surveys, only quantify the percent cover, thickness of the leaf mat, and bleaching within the lower intertidal when that portion of the surfgrass habitat is exposed during minus tides. In most cases, transects are parallel to shore and observers rarely enter the water beyond ankle deep.

Statistical power analysis of the spring 2017 data collected along 5 surfgrass transects in the AOPE and three reference sites revealed that N (the number of transects) needed to meet an α = 0.2 (20-20-20 rule) ranged between 5 and 9 transects at reference sites but nearly 36 in the AOPE. Previously collected site specific data (5 transects per site) was used to do the surfgrass power analysis. Surfgrass cover was lowest and most variable at the AoPE site (mean 25.4% 18.0% SD), was 40% at the reference sites (El Pescador 61.8%  15.9, El Matador 48.7%  17.1, Leo Carrillo 40.1%  10.9). Given α=0.2, power=0.8 (1-0.2), and effect size of 0.2 (20-20-20 rule), power was lowest for the AoPE site due to its variability and low cover (power = 0.41, 36 transects needed to achieve 0.8). Power was good for the reference sites with only six transects required at El Pescador and Leo Carrillo and nine at El Matador to achieve 0.8 power and meet the 20-20-20 rule. The high variablitiy of surfgrass percent cover along transects, limited occurrence, and reduced spatial extent in the AOPE relative to reference sites provides little scope to amend surfgrass monitoring by increasing the N, at the AOPE site. Data results from transects will provide high resolution data on percent cover, mat thickness, and basal burial that will be statistically evaluated and presented in annual reports and to regulatory agencies for independent assessment. The sliding α (type I error) relative to effect size will help detect smaller impacts. As described in 5.1, if α ≤ effect size for any α ranging from 0.000 to 0.500 for a particular assessment variable, the respective habitat will be considered impacted for the period of assessment (α and effect size rounded to three significant figures). In other words, if a 50% reduction in surfgrass is seen at the AOPE site, it will be considered impacted if α < 0.5. This is a very conservative approach and one that is likely to detect any ecologically significant impact at the site.

Surfgrass is dependent on shallow rocky habitat; thus, it can be assumed that surfgrass habitat along sandy beaches are absent if rocky substrate between 0 and -12 ft. MLLW is absent. For this reason, surfgrass sampling will be established adjacent to rocky intertidal sampling sites to take advantage of intensive mapping and sampling already proposed for each site. Surfgrass sampling will be conducted along eight transects at the AoPE and the three reference sites from 0 ft MLLW to the extent of the habitat seaward of 20 m (Figure 4-3).

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Transects were distributed between existing surfgrass areas adjacent to both the rocky bench and boulder habitat intertidal transect sampling locations. Transects were located in a shore normal orientation, when possible, to cover representative habitat surrounding the rocky intertidal sites to account for spatial differences associated with wave exposure, sand movement, and desiccation. The shoreward point of each transect was marked with a fixed bolt inshore of adjacent surfgrass habitat. Compass headings and weighted lines will be utilized to facilitate consistent placement of transects. Sampling at low tide will require the biologist to enter the water up to waist deep wearing a wet suit but data collection is conducted visually without snorkeling or diving gear. Surf conditions will greatly effect access to surfgrass transects, and conditions will need to be evaluated on a daily basis. Point counts recording presence/absence is collected every 0.1 m, or 200 points along each transect.

For each transect, two additional metrics: 1) thickness of leaf mat, and 2) depth of rhizome burial, are measured to

evaluate changes in condition of surfgrass through time. The depth of burial is determined at each of the 25 locations that the thickness of the leaf map is measured throughout each site. Depth of burial is determined by inserting a thin wooden rod (pencil) with graduated centimeters (cm) markings on it to the point of refusal (rock). The depth is recorded in cm. If no sand is present it is scored as a “0” and the substrate noted as rock. If the sand is one cm or less then the depth is recorded as “1 cm” and the substrate Photo 4-4: Measurements are taken using a graduated recorded as rock. For all burial depths greater than 1 cm the probe to determine depth of burial of the surfgrass rhizome depth is recorded to the nearest whole cm and the substrate mat while the density of the leaf canopy are determined by measuring the canopy mat thickness of the un-aggregated recorded as sand. leaf layer.

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Figure 4-3: Surfgrass Transects in the Broad Beach AoPE

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Thickness of the leaf mat is measured using calipers. This sampling measures the mat thickness of surfgrass either laying on the sediment or floating in water by determining the average number of millimeters of mat thickness. This is determined by averaging the measured leaf mat thickness in millimeters over five separate measurements within a 0.2-m transect segment. The thickness is determined as a flattened, but not crushing, measurement where leaf to leaf contact is firm but leaf shape is not distorted in the calipers. A total of 25 measurements are collected for each site and distributed among the five Photo 4-5: Typical surfgrass habitat within the AoPE where transects, assuming adequate surfgrass extent over each measurements would be taken to determine depth of burial of transect. The meter mark of the first measurement, the surfgrass rhizomes and canopy mat thickness. substrate (rock or sand), depth of rhizome burial, bleaching, and flowering is recorded. The thickness of the leaf map is measured as a surrogate for surfgrass health, based on a general discussion with the SAP and similar techniques applied to regional MPA monitoring sites. Similarly, rhizomal burial provides site specific information about the variability of the surfgrass habitat for assessment by biologists and regulatory agencies regarding potential project impacts. In both cases neither will be utilized as a metric for assessing impact with only percent cover and spatial extent used as an assessment criteria metric.

The fixed location of transects and recording of meter marks during sampling serves to track localized changes of surfgrass condition, extent, and sand deposition or erosion for the portion of transects within the intertidal. As part of the gap analysis subtidal mapping of surfgrass will provide additional information on spatial extent of surfgrass. Surfgrass sampling will be completed prior to sand nourishment during the spring and fall and following sand nourishment each year in the fall prior to field sampling.

Sandy Beach Sampling

The CDP notes that the beach monitoring methods must be capable of determining:

1) Whether the portion of Broad Beach covered by non-native sand develops a sandy beach macroinvertebrate fauna similar to the reference beaches, and 2) Whether the Project adversely impacts the beach ecosystem west and east of the Project.

The sampling design for the sandy beach monitoring is based on the South Coast MPA Baseline methodology (Dugan et al. 2015 and Schlacher 2012). Quantitative sampling will be conducted on 11 vertical format (shore-normal) transects that extend from the lower edge of terrestrial vegetation or the bluff to the lowest level exposed in the swash zone at each monitoring site. The number of transects was determined using power analyses from data collected during a pilot study in May 2016 (see Section 2.1.1) and applying the sampling design criteria noted in the CDP (i.e. 20-20-20 rule). Previously collected site specific data was used to do the power analysis. Results of the data displayed a log-transformed mean beach faunal abundance of 1.95 with standard deviation of 0.41. Given α=0.2, power=0.8 (1-0.2), and effect size of 0.2*1.95= 0.39, yielding N = 21 for two samples (transects), or 10.5 per sample rounded to 11 transects, similar to results presented in Dugan et al. 2015

Sampling transects will be evenly distributed along the entire length of each sampling site, with a minimum of 10 m between beach transects. Beach transects will be aligned with the coastal profile transects, to the maximum extent possible, in order to directly couple biological sampling, grain size distribution, and profile data to aid in developing a good understanding of Project sand movement and biological resource distribution relative to beach profile changes through time. Sampling will be done during predicted low tides

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan of 0.75 m above MLLW or lower and constrained to occur within two hours either side of low tide. Sand beach macroinvertebrate sampling will be completed during the spring and fall of each year. For the year prior to sand placement and each year fall sampling events complete physical and biotic characteristics will be assessed. Species accumulation curves will be developed with abundance, richness and full taxonomy evaluated for all samples as well as grain size analysis and wrack cover. During the spring sampling events, species accumulation curves will be built from sampling all unique organisms for each beach transect and adding additional transect samples until such time as the accumulation curve has approached an asymptote and an estimate of total species may be calculate, or until all eleven samples have been sorted for unique species. The collector curve will be employed followed by development of a Coleman accumulation curve to estimate the total species richness of the beach following Coleman et al. (1982). The results of the spring sampling will be estimators of species richness for each sampled beach. Physical characteristic information regarding grain size analysis and wrack cover will also be collected in the spring and analyzed.

To characterize the beach, the beach width and swash zone will be measured from the lower edge of terrestrial vegetation or the bluff to the lowest intertidal level exposed and the beach slope will be estimated at the upper, middle, and lower tidal sampling levels. In addition, surf zone wave height and period will be estimated at each site during each sampling day. Median sediment grain size will be determined from sand samples taken at each tidal level along each of the 11 transects at each beach.

Each vertical transect will be divided into three uniformly spaced levels (upper, middle, and lower tidal levels per Schlacher et al. 2012) to allow potential analyses of intertidal zonation. The upper level will correspond to the area above the upper wrack zone and the lower level will correspond to the upper swash zone, with the middle level located equidistant between the upper and lower levels. This collection process is intended to evenly distribute sampling across the vertical range of the beach; however, the sample unit is the beach transect and not individual elevation zones.

Abundance of wrack will be quantified along each transect using a point contact method to quantify percent cover presence to the nearest 0.1 m and depth of wrack recorded to the nearest centimeter. Documentation of wrack along beach transects will provide information regarding the species composition of the wrack and enumeration of small dispersed quantities of wrack potentially not captured from UAV mapping conducted to quantify wrack as a broader feature class. Neither wrack percent cover nor wrack spatial extent will be utilized as impact assessment criteria but rather provide additional site specific information to project biologists and regulatory agencies to evaluate conditions in the AoPE and reference sites.

In spring and fall sampling, 13 randomly spaced cores will be collected alone the transect line in each of the three levels and pooled. The cylindrical core (10-cm diameter) will be taken to a depth of 20 cm. The 13 cores from each of the three transect levels will be composited and sieved through an aperture of 1.5 mm mesh. This sampling design yields a sampling area of a minimum of 0.3 m2 per sampling transect recommended by Schlacher et al. 2008.

Sediments will be removed from the accumulated core samples from each of the sampling levels by sieving. All invertebrates and sediment retained on the sieves will be placed in labeled jars, chilled, and transported to a laboratory for preservation and processing. All invertebrates will be preserved in buffered formalin in seawater for later identification. If large quantities of gravel are collected as part of sampling, elutriation will be conducted consistent with methods utilized during MPA sand beach monitoring described in Dugan et al. 2015, prior to sorting.

Sampling will be conducted at six locations:

 Broad Beach (Project Site)  Lechuza Cove (Site of Concern);  Zuma West (Site of Concern);  Leo Carrillo Beach (Reference Site);

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

 El Pescador (Reference Site), and;  Zuma East (Reference Site)

For one year prior to sand placement and for each fall sampling event, infauna collected during the sampling events will be evaluated for, species richness (number of unique species per linear meter of beach), species population abundance, and diversity (Shannon’s index) for each of the sampled transects. All animals retained on the sieves will be identified and enumerated. Diversity and abundance will be evaluated for separate beach levels, as well as in aggregate. Richness alone will be determined for each beach for the spring sampling events post sand placement.

Subtidal Habitat Sampling Subtidal Rocky Reef Habitat Sampling Scientific divers will collect data on the density and relative abundance of canopy forming kelp, understory algae, and invertebrates in a series of separate surveys. Representative species and functional groups of macroalgae and invertebrate species were selected for consistency with existing baseline data sets collected as part of the South Coast MPA monitoring surveys and other regional data sets collected near the AoPE and at reference sites (Table 4-3). Density estimates for these species will be recorded to evaluate differences between the AoPE and two reference sites (Leo Carrillo/Sequit Point and El Pescador). The subtidal rocky reef habitat data will be collected from 12 transects (10 m long by 2 m wide) distributed in depths from -15 to -35 ft. MLLW2. The number of transects surveyed in 2017 was based on a statistical power analysis of the subtidal surveys conducted in 2016 in which 22 plots were needed to fulfill the 20-20-20 rule for kelp density. For the 2016 surveys circular 10 m2 quadrats (1.78m radius) were used and primarily targeted giant kelp located in the central portions of rocky reef in waters greater than -30 ft MLLW. Amendments to the location and size of the survey transects was requested by regulatory agencies following the 2016 surveys prompting the transition to more conventional 10 m long by 2 m wide transects currently described later in this section. In 2017 surveys were conducted at 12 transects per site encompassing 240 m2 area, slightly more than the area covered by the 2016 the circular quadrats. It was assumed that the greater area represented by fewer transects targeting a broader range of species and functional groups would reduce variability and achieve sufficient power based on the assumption that variability scaled with area. Following spring 2017 data collection, power analysis derived from the data series displayed sufficient power for broad functional groups including sessile invertebrates and macroalgae but not for specific species. Spring 2017 site specific data (12 transects per site) were used to do a Subtidal Rocky Reef power analysis. The analysis was performed on each of the individual species and functional groups for each method. Power for percent cover evaluated from UPC data was lowest and most variable for specific species for both UPC and swath sampling methods. At the AoPE site UPC data for broad functional groups, all sessile invertebrates and all algae, provided power of 0.98 and 0.83 respectively. The resulting number of transects needed to achieve 0.8 power in the AoPE was 5 and 11 for each respective category. Power was variable for the reference sites with seven and 44 transects required at Leo Carrillo and 21 and 13 for El Pescador for the same broad functional groups. For swath data power ranged from 0.26 for sea stars to 0.64 for giant kelp resulting in the need for 700 or 23 transects to meet 0.8 power. Because transects were moved to the edges of subtidal rocky reef structures to track sand deposition or erosion stipate macroalgae and motile macroinvertebrates where more variable than in the central portions of rocky reefs sampled in 2016. Based on these findings an additional 12 swath transects were added to each site to increase power for motile macroinvertebrates and macroalgae and the sampling intensity will continue to be reevaluated after subsequent data collections to further adaptively manage the data collection methods with respect to the 20-20-20 rule. At each monitoring site, visual surveys will be conducted via SCUBA by experienced scientific divers to quantify the density and

2 This results in a total sampled area of 240 m2 per site, slightly more than the sampling area conducted in fall 2016, which met the 20-20-20 goal based on power analysis of the data collected from the AoPE and reference sites. This sampling effort also matches with the south coast MPA baseline monitoring program protocol (Pondella and Casselle 2012).

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan relative abundance of algae and invertebrate populations as well as record the substrate type along each transect. Paired transects will be stratified on selected reef areas (alongshore) and located at both the upcoast and downcoast margins of the reefs to ensure that representational sampling of the rocky reef habitat captures potential effects from sanding (Figure 4-4, Figure 4-5, and Figure 4-6).

Table 4-3: Subtidal Rocky Reef Functional Groups, Representative Species, and Substrate Enumerate on Transects Category/Functional Group Representative Species/Substrate Survey Method Substrate Bedrock (≥ 1 m) Uniform Point Count (UPC) Boulder (10 cm- 1 m) Cobble (≤ 10 cm) Sand Other Bare UPC Chlorophyta – Green Algae UPC Phaeophyta – Brown Algae Macrocystis pyrifera (>1m) Swath, UPC, #stipes/ plant Macrocystis pyrifera subadult (>10 cm) UPC/ Swath Eisenia arborea UPC/ Swath Pterygophora californica Sargassum horneri Laminaria spp. Cystoserira osmundacea Rhodophyta – Red Algae UPC Coralline Algae Crustose coralline UPC Articulated coralline Anthophyta – Surfgrass Phyllospadix spp. UPC Eelgrass Zostera spp. UPC Cnidaria – Anemones UPC Cup corals UPC Hydroids UPC Porifera – Sponges UPC Bryozoa – Bryozoans UPC Chordata – Tunicates UPC Annelida – Polychaeta Phragmatopoma californica UPC worms Diopatra ornata Chaetopterus spp. Miscellaneous Bivalves, Barnacles, etc. UPC Invertebrates Gorgonians Eugorgia rubens Swath Lophogorgia chilensis Muricea fruticosa Muricea californica Abalone Haliotis corrugata Swath Haliotis cracherodii Haliotis fulgens Haliotis rufescens Sea urchins Centrostephanus coronatus Swath Strongylocentrotus purpuratus Strongylocentrotus franciscanus

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Figure 4-4: Rocky Reef Subtidal Habitat Survey Transects in the Broad Beach AoPE

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Figure 4-5: Rocky Reef Subtidal Habitat Survey Transects in the Leo Carrillo/Sequit Point Reference Site.

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Figure 4-6: Rocky Reef Subtidal Habitat Survey Transects in the El Pescador Reference Site.

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Reef areas were selected based on depth, size (minimum size of 30 m x 15 m), and persistence of kelp canopy (based on regional LIDAR data). Reef areas selected within the AoPE were chosen based on the proximity to the beach nourishment site and selection criteria stated above. Pairs of transects will be sampled in each of the six sites with transects capturing the sand/rock interface, vertical surface, and upper reef habitat (Figure 4-7). Permanent bolts/markers will be placed near the edge of the reef and 5 m away along the desired heading. The initial location of the bolt/marker adjacent to the reef edge will be placed to allow a minimum of 1 m of transect to lie on sand substrate to allow for tracking sand erosion/deposition during future survey events. In cases where a continuous reef area exists in places where transects cannot be placed in the upcoast or downcoast orientation, transects will be placed along the inshore and offshore margins. Spring 2017 sampling data was evaluated and slight changes to transect placements in the AoPE where requested by regulatory agencies. Additionally five contiguous 20 m transects (one continuous100 m transect) were added to the shallow subtidal (-15 ft.) within the surfzone in the AoPE and reference sites to document and enumerate feature classes and biotic communities (Figures 4-4, 4-5, and 4-6). The 100 m transects within the outer surf zone will be located in areas currently or previously mapped to consist of low lying rock reef or boulder/cobble habitat to document temporal changes in sand cover and species assemblages. The transects will be videotaped and associated species quantified and described annually for inclusion in annual reports. Evaluation of the subtidal rocky reef sampling methods will examined yearly to identify ways to improve the sampling program to meet the design objective of detecting a 20 percent effect size with an 80 percent probability (i.e., the statistical power) using a type I and II error = 0.2. Subtidal rocky reef habitat sampling will be completed prior to sand nourishment during the spring and fall for a total of three times (fall 2016, spring 2017, and fall 2017) and following sand nourishment each year in the fall prior to field sampling.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Figure 4-7: Rocky Reef Subtidal Habitat Survey Transect Placement and Configuration

Subtidal Rocky Reef Sampling Methods Three sampling methods will be used to quantify the density and/or cover of algae, invertebrates, and substrate along each transect, as well as to record the level of sand deposition/erosion adjacent to the subtidal rocky reefs. Swaths (or band transects) will be used to estimate the density of species, UPCs to estimate the percent cover of species/substrate, and linear distance measurements to document sand levels relative to the reef at individual transect locations. A team of four scientific divers will conduct the sampling; each transect will be sampled by two scientific divers with each diver employing a different method. Swath Transect Sampling

The purpose of the swath sampling is to estimate the density of specific macroalgae and selected invertebrates (Table 4-3). The invertebrates and macroalgae are enumerated in each of the twelve 10 m long x 2 m wide transects and a parallel transect approximately 5 meters away, for a total of 24 transects (swath) (Table 4-3). Scientific divers will utilize underwater slates fitted with preprinted datasheets to record all targeted species as they slowly swim along one side of the transect and then the other. Surveys will be nondestructive, but the areas containing crevices searched and understory algae pushed aside. Species with greater than one-half of its biological area inside the transect will be counted. Adult and sub-adult giant kelp plants will be counted with individuals (adults) taller than 1 m recorded, number of stipes at 1 m above the substrate counted, and greatest diameter of the holdfast entered on the datasheet. Stipate (prostrate) brown

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan algae (Table 4-3) with stipes taller than 30 cm and Laminaria farlowii with a blade greater than 10 cm wide will be counted. All other macro, foliose, and encrusted algal species will be quantified in UPC counts. Any observations of abalone live or dead that are made during the surveys will be reported, irrespective of inclusion in sampling location.

UPC Sampling UPCs will be used to estimate the percent cover of species, functional groups, and substrate along each 10-m long transect. Scientific divers will record the substrate type and species/functional group (Table 4-3) at each 0.1 m mark along the transect to record 100 points along each transect. Only the species/functional group occurring directly attached to the primary substrate will be counted. Substrate type will be recorded as sand, cobble (< 10-cm diameter), boulder (10-cm – 1-m diameter) or bedrock (> 1-m diameter).

Linear Distance Measurements As previously described, individual transects will be initially placed so that 1 m of each transect lies along the sand adjacent to the reef habitat. During each initial transect setup, notes will be taken on the structure (e.g., vertical, overhanging, sloped, boulder) of the vertical surface and qualifiers (e.g., fine sand, underlying rock, surfgrass) of the 1 m of substrate where each transect begins (Figure 4-7). The distance from the bolt/ marker to the sand/substrate interface will be recorded during each survey to document the linear distance or level of sand deposition or erosion at each transect (Figure 4-3). The linear distance measurement will be a snapped (tight) meter tape measurement from the bolt/marker to the bottom/base of the rocky reef and bottom substrate interface. The establishment of the vertical surface measurement locations will avoid obstructions (rock outcroppings or boulders) that interfere with implementing a taught measurement, to the maximum extent possible. Essentially the placement of the initial transect bolt that is placed to measure the vertical surface is located on vertical rock services that meet the stated criteria. These measurements will also be utilized as ground truth reference points to examine the accuracy of subtidal mapping of sand heights collected throughout the AoPE and at reference sites.

Eelgrass Sampling The California Eelgrass Mitigation Policy (CEMP) sampling guidelines will be employed to monitor for adverse impacts on eelgrass associated with the Project (NMFS 2014). Eelgrass area impact assessment will be conducted by an analysis that compares the pre-project condition of eelgrass habitat in the AoPE with the post-project condition relative to eelgrass habitat change at a reference site(s). Adverse impacts can be caused by both direct and indirect effects of the Project and are identified by differences in spatial extent of eelgrass and/or changes in density. Based on CEMP requirements, eelgrass monitoring is composed of mapping to determine eelgrass spatial extent and density. In addition to acoustic mapping, density is also measured in-situ by scientific divers conducting eelgrass mapping and turion counts. Eelgrass sampling will be conducted within the Broad Beach AoPE and at each of the reference sites (Sequit Point, Leo Carrillo, El Pescador, and El Matador).

Field sampling will consist of turion counts in 1/4-m2 quadrats distributed uniformly along 100-m ground truthing transects placed randomly through acoustically mapped eelgrass beds. The transects vary from year to year and serve to evaluate eelgrass communities by facilitating the placement of quadrats over a diverse area of the bed and provide an extended observation opportunity for scientific divers to note associated species, disturbance, reproductive flowering, and changes in density. In accordance with the CEMP, eelgrass turion density is a character of the plants while vegetated cover is a character of the beds. For this reason, all sampling will be performed only in areas where eelgrass plants are present (i.e., no zero turion counts will occur). The sampling will be performed at a replication of at least n=50 quadrats at each site, however, greater replication may be added, if the field biologist sees great fluctuation in densities within the bed. The 50 replicates used for sampling is based on generally consistent density observed in the interior portions of Z. pacifica beds along coastal regions.

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Sandy Subtidal Sampling To assess potential impacts to sandy subtidal macroinvertebrate infauna, an extension of the sandy beach sampling will be conducted offshore within the Broad Beach AoPE, sites of concern (Lechuza Cove and Zuma West), and two reference beaches (Leo Carrillo and Zuma East). No sampling will be conducted at the El Pescador reference site as the subtidal habitat is not similar to the AoPE or the other reference sites because of extensive bedrock and boulder/cobble mapped throughout the subtidal adjacent to the beach. Benthic cores will be collected and processed fall 2016 and 2017 (pre-sand nourishment) to obtain macroinvertebrate infauna and sand grain size baseline data. Macroinvertebrate infauna and grain size sampling will be conducted offshore within the AoPE, sites of concern, and the two reference beaches each fall following sand nourishment to determine the seasonal distribution of Project sand and its contribution to changes in grain size within and near the Project footprint. Macroinvertebrate infauna samples will be collected by divers using a cylindrical core (10-cm diameter) taken to a depth of 20 cm along each of 11 subtidal transects collocated to align with the onshore beach transect locations and spacing. Samples will be collected at the -18 ft, -24 ft, and -30 ft MLLW isobaths. As a result, samples will be collected at five beaches on eleven transects at three depths for a total of 165 samples. If subtidal transects cross rocky habitat, sampling will be moved laterally to the first point of sand occurrence that allows for sampling to full core depth.

The -18 ft isobath was considered to be the shallowest depth that could be safely sampled on the open beach face at all sites. This would allow a vessel to remain outside of the breaker zone and still tend divers collecting samples. Samples will be sieved through an aperture of 1.5 mm mesh and all macroinvertebrates retained on the sieves will be placed in labeled jars and transported to the laboratory. All macroinvertebrates will be preserved in buffered formalin in seawater for identification and enumeration. Macroinvertebrate infauna samples collected after the 2017 pre-sand nourishment sampling will not be processed unless the median grain size is greater than 0.5 mm, the level that increased grain size would be expected to potentially affect benthic biota community structure.

Grain size samples collected concurrent with biotic samples will be processed in a serial progression beginning first with the -18 ft isobath samples analyzed. In a stepwise manner, the sample analyses would be expanded as dictated by shallower samples exceeding trigger levels for biotic analyses. The median grain size for the AoPE was determined to be 0.25 mm based on evaluations of sand from the supratidal, intertidal, and subtidal (Moffatt & Nichol, 2012). Based on the larger grain size of the proposed nourishment sand a median grain size of 0.5 mm or above was Photo 4-6: Interferometric sidescan sonar backscatter mosaic at Broad determined to be an appropriate trigger that would Beach (2014) illustrating coarse grain sand chutes formed by rips extending perpendicular from shore. These energy features create coarse warrant analyzing benthic infauna samples. The grain sand concentrations along the beach that generally extend to physical grain size trigger was determined by the depths less than -20ft. MLLW. SAP based on changes in grain size that are likely to generate a response in macroinvertebrate infauna within the nearshore subtidal habitat.

Considering existing coarse grain sand chutes have been documented to exist along the Broad Beach AoPE and at reference sites these areas are expected to exceed the median grain size trigger, if sampled. The course grain sand chutes where not sampled during the fall 2016 and will be avoided during the fall 2017 pre-placement sampling. The chutes are discrete features and rarely reach the -18 ft isobath. As a result, avoidance of the course grain sand chutes will be implemented during post placement subtidal sand sampling to remain consistent with pre-placement sampling. If avoidance of the course sand chutes is required at

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan either of the -18 ft, -24 ft, or -30 ft MLLW depths scientific divers will sufficiently document, map, and photograph the areas during sampling and notify regulatory agencies to examine potential sampling alternatives, if warranted.

If the grain size trigger is not exceeded at the -18 ft isobaths for the Broad Beach AoPE, no additional samples would be analyzed for grain size or infauna at either Broad Beach or the reference sites. However, if the trigger is exceeded, AoPE samples of the -24 ft isobaths would be analyzed to determine the spatial extent of the D50 exceedance footprint. If need be, the sampling will be extended to the -30 ft isobaths if the grain size trigger is also exceeded on the -24 ft contour. Samples would then be processed for benthic species richness and abundance for all subtidal samples collected within the AoPE and reference sites.

The samples would be processed for all pre-nourishment time steps and the post-nourishment time steps for which trigger grain size is exceeded. The elevations processed will be limited to the affected elevation(s), and the next lowest elevation that has been sampled. Species richness and abundance analyses would be completed on impacted and non-impacted samples to assess potential differences as described in Section 5. SAMPLING PROGRAM SCHEDULE, COORDINATION AND REPORTING The program work is designed to include sampling and data collected for two seasons prior to implementation and 10 years following implementation. It is presently anticipated that a total of three sampling events will be completed prior to initial sand nourishment, with some additional baseline data available from previous programs as well as data collected during the early monitoring design period. Existing baseline data sets include the 2003-2016 kelp canopy data from CRKSC, habitat mapping completed in spring and fall 2016 at the AoPE and reference sites, beach and subtidal sampling completed in fall 2016 and a complete mapping and sampling completed in spring 2017. Additionally, South Coast MPA data exists for the Broad Beach AoPE sand beach and reference sites as well as for rocky intertidal sampling sites (Lechuza Point) and the reference site (Sequit Point). South Coast MPA subtidal rocky reef data also exists for the Leo Carrillo reference site and less importantly for Point Dume since it lies outside of the proposed boundaries and constraints of the identified reference site criteria.

Annual marine habitat monitoring reports must be submitted by December 31 of each calendar year for review and approval by authorizing agencies. The program calls for coordination with the SAP, CCC, Corps, and resource agencies on an as needed basis to discuss annual monitoring execution, the monitoring results, review the monitoring plan, and consider adaptive management actions. In addition, mitigation approaches and opportunities may need to be discussed if adverse impacts are identified within one or more habitats. More frequent SAP meetings may be held if needed. Table 4-4 identifies the schedule for primary elements of the monitoring program through the first 5 years of implementation, and assumes no changes in the subsequent 5 years unless through consultation with the SAP and agencies, and approval from the permit- authorizing agencies.

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Table 4-4: Proposed Sampling Schedule First 5 Years (Shaded Cells Indicate Sampling Completed in Accordance with this Monitoring Plan)

Post-Construction Pre-Construction Year 1 - 2018 Year 2 - 2019 Year 3 - 2020 Year 4- 2021 Year 5 - 2022 Spring Fall + Spring Fall 2016 2016 2017 2017 Spring Fall Spring Fall Spring Fall Spring Fall Spring Fall Habitat Mapping All Habitats X X X X X X X X Kelp Canopy (2003-present) X R Sand Beach Sampling Intertidal Sand Abundance, Richness, and X* X* X X X X X X Density Richness X* X* X X X X X Grain Size and Wrack X* X* X* X X X X X X X X X Subtidal Sand X* X* X X X X X X Infaunal, and Grain Size Subtidal Infaunal Processing X* X* (Abundance, Richness, and X (TB) (TB) (TB) (TB) (TB) Density) Intertidal Sampling Rocky Intertidal Sampling X X X X X X X Surfgrass Sampling X X X X X X X Subtidal Sampling Subtidal Reef Sampling X+ X X X X X X X Eelgrass Sampling X X X X X X X X

Coordination and Reporting Reporting (Dec. 31 X X X X X X annually) SAP & Agency Review X X X X X X X X X X X X X X Mtg. Adaptive Management X X X X X X X (TB) – Trigger Based analyses; Sampling will be performed with each event, but analyses will be driven by exceedance of median grain sized triggers. If the D50 grain size trigger is tripped at the -18-ft contour at Broad Beach, samples from pre-Project at Broad Beach and reference sites will be analyzed along with the event that exceeded the trigger. (R) – Assessment of Kelp Canopy will be evaluated and assessed as portion of the 5-year monitoring report to examine relationships between Kelp Canopy cover and Kelp counts conducted as part of seasonal Subtidal Reef sampling. * -Sampling was conducted but processing of samples was not executed per plan requirements, processing will take place prior to sand placement. + - Sampling was conducted consistent with June 2016 MHMMP methods, similar but not consistent with currently accepted methods described in this MHMMP

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CRITERIA FOR DETECTING ADVERSE IMPACTS

PERFORMANCE CRITERIA Collectively, regulatory agencies (e.g. CCC, USACE, NMFS, etc.) are in general agreement to the proposed performance criteria approach with the caveat that agencies (in consultation with the SAP) may elect to assess potential impacts on the basis of best professional judgement and cumulative bodies of evidence as well if the proposed approach is considered insufficient or unconvincing at a later time. Explicit analytical approaches will be determined once there is sufficient data to consider what will be most appropriate, based upon consultation with the SAP and regulatory agencies. Furthermore, independent regulatory agencies may assess impacts as they see fit should any consider the proposed (or later selected) approaches insufficient for their purposes. Regardless of the analytical approach ultimately employed, the following rules will be used when assessing change in each performance variable:

1) If α (type I error) ≤ effect size for any α ranging from 0.000 to 0.500 for a particular performance variable, the respective habitat will be considered impacted for the period of assessment (α and effect size rounded to three significant figures). 2) If α > effect size for any effect size ranging from 0.000 to 0.500 for a particular performance variable, the respective habitat will be considered unchanged relative to Reference site(s) for the period of assessment (α and effect size rounded to three significant figures). 3) If the effect size is > 0.500 and α is > 0.500 for a particular performance variable, assessment of the respective habitat for the period of assessment will be considered inconclusive (α and effect size rounded to three significant figures) and the following steps will be taken: a) The sampling design may be revised to increase the statistical power to an expected value of at least 80%. Whether this effort is necessary will be based on the history of the performance of the sand nourishment site. For example, if the analyses were conclusive in previous periods, then a single inconclusive analysis would not be sufficient to invoke a revision of the sampling design. b) If needed, the revised sampling design will be implemented the following year. c) If in the following year the criterion (no change) is met, then the criterion will be considered to have been met the previous year as well. If in the following year the standard is not met (impact), then the criterion will be considered to not have been met the previous year as well. d) This process will continue until impact can be assessed, unless the regulatory agencies and/or the Corps changes the criterion. 4) Monitoring data will be evaluated annually to determine if changes need to be made to the sampling program to bring it closer to the design objective of detecting at least a 20 percent deviation from the performance criterion (i.e., the effect size) with an 80 percent probability (i.e., the statistical power) using a type I error (α) = 0.2. Note that this 20-20-20 rule does not apply to assessment per se; rather, the 20-20-20 rule was used to guide the sampling design, to ensure that sampling is sufficient to detect impact. Metrics that do not meet the 20-20-20 sampling design rule because they are variable or rare can and will still be analyzed as described above. Statistical Analysis of Change Three alternative statistical analysis approaches to evaluate impact of the sand nourishment activities are described below. The alternatives are presented in order of preference, with the preferred analysis first (Plan A). Contingency approaches are presented in case of inability to establish tracking reference sites, or complete loss of Reference sites. Different approaches may be applied to different metrics depending on the data available for that metric, with the order of preference maintained within the analysis of each metric.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

This gives us flexibility to adapt to the data available while prioritizing the most rigorous and fair approach (A) to the benefit of all parties’ confidence.

Plan A) Before-After-Control-Impact Paired Series (BACIPS) Design

We plan to execute a BACIPS assessment as the preferred option for evaluation of potential Project impacts. Differences in physical characteristics can cause biological assemblages to naturally differ greatly among areas, while seasonal and inter-annual differences in oceanographic conditions can cause the biological assemblages to fluctuate greatly over time. In this design, Impact and Reference sites are sampled simultaneously multiple times before and after an impact. Here the AoPE site is referred to as the Impact site. For the ith sampling survey conducted in period P (Before, B vs After, A), the difference (delta, hereafter ∆) in the sampled response variable (e.g., functional group density), between the Reference site(s) (R) and impact site (I) is estimated as:

∆푃푖 = 푅푃 푖 − 퐼푃 푖

The response variables are often log-transformed to meet additivity assumptions (Osenberg et al. 1996). The effect size is estimated as:

Effect = ∆퐵푒푓표푟푒 − ∆퐴푓푡푒푟 Where ∆ is the mean difference for a period.

We will perform the BACIPS analysis in two different complementary ways to maximize information from the monitoring data.

A) Impact Control B) Impact Control

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Figure 5-1: Illustration of Patterns of Variation in Simulated Density Data and Resulting Delta (Δ) Values from Paired Sites that Track Each Other (A) Versus Non-tracking sites (B) First, a traditional t-test and confidence interval approach will be used. The mean difference in each period, ∆̅Pi, will be used to estimate the spatial variation between the sites, and the null hypothesis is that the difference between ∆̅Before and ∆̅After is zero (∆̅Before − ∆̅After= 0). The After period will be considered

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan both in aggregate (averaged), as new time periods accumulate, and as 1-year intervals, where the most recent year is compared against the Before period and the immediately preceding year, to evaluate possible responses to ongoing activities at the Impact site. Differences (∆ values) between the impact site and each Reference site data plotted over time will be used to choose, if judged appropriate in consultation with the regulatory agencies and SAP, Reference site(s) that track the impact site most closely (paying particular attention to pre-renourishment data at the impact site). The benefit of this is illustrated in Figure 5-1, which shows simulated data (top panels) from two pairs of sites. “A” represents two sites that track each other (i.e., have high coherence), while “B” represents two sites with poor tracking. Lower panels show resulting ∆ values. High coherence of site pair “A” leads to low variability in ∆ values , which should lead to relatively high statistical power (Figure 5-1). We will strive, however, to retain at least 2 Reference sites in the analysis, and at least 3 Reference sites, where appropriate, will continue to be monitored regardless in case of future site-specific variability or site disturbance. If more than one Reference site is used, analysis choices include: 1) partially nested ANOVA (here site nested in treatment), 2) single factor ANOVA with 4 sites using planned comparisons to test the effect of treatment or, 3) an alternative analysis in consultation with the SAP/agencies. Using multiple reference sites would help reduce the effect of site-to-site differences in the References, but would work best if more than one Reference site tracked the impact site. Prior to calculating ∆ values, data will be transformed as needed to meet assumptions of variance homogeneity, normality, and additivity, with adjustments for zeros if needed. This approach will be used each year in the time series.

Secondly, a new approach called Progressive-Change BACIPS, which generalizes and expands the scope of BACIPS analyses (Thiault et al. 2016), will be employed. BACIPS designs generally assume that effects are sudden, constant and long-lived, but complex ecological interactions or gradual or ongoing interventions may create delayed or progressive responses, potentially making classic analyses unreliable. Progressive-Change BACIPS can be described as follows. First, for each performance variable, we calculate the time series of differences (∆ values) between the Impact and Reference sites as described above. Second, competing models of the full-time series of differences are compared, and the best model is then selected using Aikake Information Criteria (AIC) model selection guidelines. AIC is a measure of the relative quality of statistical models for a given set of data, and therefore provides a means for model selection. Finally, the best model is used to estimate the effect of the Project. Four models will be tested: a step-change in the difference (in which the difference is immediate and constant through time as assumed by the classic BACIPS model), a linear change (∆ increases through time at a constant rate), an asymptotic change (in which the intervention causes a continuous change in the ∆ that eventually approaches an asymptote) and a sigmoid change (in which the intervention causes a continuous change in the ∆, that shifts from initially accelerating to decelerating). Thiault et al. (2016) have published R code to execute this analysis. This approach will only be feasible after obtaining 5 years of data in the After period, and will be employed then as a comparison to the traditional BACIPS approach described above.

Plan B) Separate Confidence Interval Test using Multiple Performance Standards Use of the Separate Confidence Interval (SCI) test to determine similarity between the impact and Reference sites involves calculating SCIs for each Reference site using within-site sub samples as replicates. The range or “envelope” of values used to determine similarity for a given performance variable is set by the upper confidence limit of the Reference site with the highest mean value for the performance variable and the lower confidence limit of the Reference site with the lowest mean value for the performance variable.

In essence, it requires the impact site to perform at least as well (in a statistical sense) as the lowest performing Reference site, while controlling for the probability of multiple low-performing assessment variables at the impact site. This standard is biased in that the null expectation is that all performance variables measured at the impact site should be equivalent to or better than the lowest value for each performance variable at any of the Reference sites. Therefore, this “envelope” approach requires that the value of the impact site be within the range of the SCI of the Reference sites.

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To illustrate this approach, imagine a hypothetical scenario in which the success of an impact site is based on nine performance variables and two Reference sites. Compliance would require: (1) the value of the means for all nine variables at the impact site be within the SCI of the two Reference sites, and (2) that the impact site not have the lowest value for more than 1/3 of the variables (in this case, no more than 3 variables). Criterion 1 ensures that the values of all the performance variables at the Impact site will be greater than that of the lower confidence limit of the mean of the Reference site with the lowest value. Criterion 2 is based on the null hypothesis that the resource value of the impact site represents a sample from the same population as the Reference sites and that the impact site behaves like the Reference sites with respect to all the performance variables. If this is true, then in the example above it follows that each of the three sites (i.e., the impact site and the two Reference sites) has an equal one-third chance of having the lowest value for any performance variable. This criterion eliminates the possibility of concluding that the impact site is in compliance when it has the lowest value for a large number of the performance variables. When applied together, the two criteria allow for the fair assessment of impact while considering site-to-site variability.

Plan C) Before-After Test

This analysis relies only on samples taken multiple times before and after the impact at the Impact site, and is used in cases where no feasible Reference site exists either due to the scale of the impact (e.g. air pollution) or in this case, potential inapplicability of proposed Reference sites. It is difficult to imagine a scenario in which this would occur; nevertheless, we present the option here for the simple Before-After assessment design. The Before-After design suffers from the disadvantage that impacts are confounded with natural variability, in this case temporal fluctuations. We will evaluate impact in this design using a t-test comparing the Before and After samples, based on the model

∆푃푖 = 휇푃 + 휀푃푖 퐻푦푝표푡ℎ푒푠𝑖푠: 휇푝 = 0 where 휇푃 is the mean in period P, 휇퐵푒푓표푟푒 − 휇퐴푓푡푒푟, and 휀푃푖 are errors. Data will be transformed as needed to meet assumptions of additivity, with adjustments for zeros if needed. This approach is a last resort and will not be used unless the first two approaches prove unfeasible. Assessment Variables Below we summarize the variables that will be statistically analyzed to evaluate impacts. Sampling design and sample size for these variables is described in Section 4. The list below can be adjusted during the project in consultation with the regulatory agencies as part of an adaptive management approach, for example in the case that impacts could be better described using alternative species groupings.

Intertidal Habitat Feature Class Mapping Evaluation metrics are indicated in Error! Reference source not found. for intertidal resources. For rocky intertidal habitat feature classes (bedrock and boulder/cobble), a reduction in feature class proportion relative to baseline conditions and Reference response scaling will be used to define adverse impacts. Surfgrass and wrack are the only biotic overlays within the intertidal habitat that will be independently mapped. Other biotic features are part of the intertidal habitats and are sampled using permanent transects and defined monitoring methods within habitats. Subtidal Habitat Feature Class Mapping For subtidal habitat feature classes, mapping metrics include bedrock and boulder/cobble reef. Kelp canopy and two parameters for eelgrass are to be used as metrics (areal extent and vegetated cover pursuant to the CEMP). Changes in sand bottom are not proposed to be used as an evaluated metric.

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Table 5-1 Mapped Habitat Feature Classes for Assessment and Evaluation. Delta (Δ) values between Impact and Reference sites in each time period will be calculated for each of these variables

Mapped Habitat Primary substrate Secondary cover Feature Class (acres) (acres) Supratidal Bedrock XX Riprap XX Boulder/Cobble XX Sand XX Intertidal Bedrock XX Riprap XX Boulder/Cobble XX Sand (Beach) XX

Wrack XX Surfgrass XX Aerial Extent XX Vegetated Cover XX Subtidal Bedrock XX Boulder/Cobble XX Sand XX Eelgrass Areal Extent XX Vegetated Cover XX

Intertidal Assessment Variables Evaluation metrics are indicated in Table 5-2 for rocky intertidal resources and Table 5-3for sand beach resources listing the assessment variable (e.g. substrate, species, or functional group and measurement. Power analysis of site specific surveys conducted in 2016 and 2017 indicate that due to high levels of natural variation in species distributions, some variables may need to be grouped under larger functional group categories (e.g. sessile invertebrates and macroalgae) to detect a smaller impact (i.e. 20% decrease). However, this does not preclude analyzing individual species or finer-level groups; if a potential impact to one of these groups is large it will be detected, and the sliding α described under 5.1 used to facilitate an appropriate level of significance. This approach will provide a comprehensive examination of changes in substrate, species, and functional groups for inspection and evaluation by regulatory agencies while meeting the 20-20-20 rule at some levels. In addition, as noted elsewhere, the fixed nature of the sampling transects increases power. Functional groups will be assessed for impact at finer levels as indicated here, therefore, before lumping takes place. In addition, species-level data will be examined within groups if an impact is detected to determine how impact was distributed among the community.

Subtidal Assessment Variables Evaluation metrics are indicated in Table 5-4 for rocky subtidal resources and Table 5-3 for subtidal sand beach resources. As described above for intertidal communities, some variables may need to be grouped under larger categories (e.g. all sessile invertebrates) to detect a smaller impact (i.e. 20% decrease).

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However, Functional groups will be assessed for impact at finer levels as indicated here before such lumping takes place. In addition, species-level data will be examined within groups if an impact is detected to determine how impact was distributed among the community.

Table 5-2 Rocky Intertidal Evaluation Metrics to be used for Assessment of Project Impact Evaluation. Delta Values between Impact and Reference Sites in each Time Period will be Calculated for each of these Variables

Sampled Intertidal Variables Measurement Sessile Invertebrates Percent Cover Anemones Percent cover Barnacles Percent cover Mussels Percent cover Macroalgae Percent cover Encrusting Corallines Percent cover Ephemeral macroalgae Percent cover Mobile invertebrates Density (#/area) Crack and Crevice Depth Depth (cm) Surfgrass Basal Burial Depth of burial Surfgrass Leaf Canopy Thickness Canopy thickness Bare Rock Percent cover Sand Percent cover

Table 5-3 Intertidal and Subtidal Sand Beach Evaluation Metrics to be used for Assessment of Project Impact Evaluation. Delta Values between Impact and Reference Sites in each Time Period will be Calculated for each of these Variables

Sampled Intertidal Variables Measurement Species Diversity Shannon Wiener Index Species Richness Number Abundance Density Grain Size millimeters Wrack Percent cover

Table 5-4 Subtidal Metrics to be used for Assessment of Project Impact Evaluation. Delta Values between Impact and Reference Sites in each Time Period will be Calculated for each of these Variables

Sampled Subtidal Rocky Reef Variables Measurement Kelp (Macrocystis) holdfasts Density (# per m2) Kelp (Macrocystis) stipes  1m length Number/Plant Kelp (Macrocystis) juveniles Density (# per m2) Understory kelp (non-Macrocystis Laminarians) Density (# per m2) Benthic non-kelp macroalgae Percent cover Sessile invertebrates (all non-worm attached Percent cover sessile invertebrates)

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

Annelida – Polychaeta worms Percent cover Hydroids and bryozoans Percent cover Sponges, Anemones, Cup Corals and tunicates Percent cover Sessile invertebrates Percent cover Mobile invertebrates (Gorgonians, urchins, Density (# per m2) abalone) Bare Rock Percent cover Sand Percent cover

DETERMINATION OF ADVERSE IMPACTS Determination of adverse impacts has two broad steps: 1) evaluation of whether or not statistically significant change has occurred in a given assessment variable, as described above, and 2) measurement of direction and magnitude of change, i.e. impact. Section 5.1 focused on the first step, the determination of statistical significance in the analysis of change. Here, the second step is described. For each assessment variable, impact will be measured in units of acre-years, and measures of impact on a given habitat area and its ecological function (i.e. biological elements associated with that habitat) will be summed to calculate total impact. As a conservative approach, habitat and function metrics will be assessed as losses only; i.e. positive change will be considered as no change; however the flexibility to consider whether or not ecological shifts are impacts is retained in consultation with the SAP and Agencies and given consensus among them.

Magnitude and direction of change will be measured in terms of acre-years for each performance variable at the AoPE (Impact) site. The Before period will be used as the baseline.

Change of habitat and function will be evaluated based on the delta values for each sampling period, integrated over the five years of initial monitoring. Below we describe this process and follow with examples.

First, for each evaluation variable X, a single value is estimated for each site and monitoring period (e.g. Fall 2019), either by averaging across sampling units (e.g. transects) or by a whole-site measure (e.g. habitat areas from mapping). These values will be used to calculate a delta value for the Impact site and each Reference site, assuming multiple Reference sites are retained, or a value from the best-matched Reference site(s) will be used in consultation with the CCC, SAP, and other Agencies, for a given sampling time i as follows:

Δ푖 = 푋푖 − 푋퐵푒푓표푟푒 Where X is the value of a given evaluation variable at a given site at time i.

Next, for each sampling time, we will calculate an effect E:

퐸푋 = ∆퐼푖 − ∆̅푅

Where ∆̅푅 is the mean delta for the Reference site(s) for that evaluation variable. Thus, a simple example would be the following:

Area of intertidal rock at the impact site is 4 acres in the Before period and declines to 2 acres after year 1.

Δ푖 is therefore -2 acres. At the Reference site, intertidal rock is 3 acres in the Before period, and does not change after year 1. Δ푖 for the Reference site is therefore 0. Effect would then be calculated as -2 – 0, or -2 acres.

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In the case of habitat, the above effects and integrated effect will be calculated directly in units of acres. Adverse change in ecological function (F) will be calculated as:

퐹푖 = 퐸푋푖(퐻퐴 푏푒푓표푟푒)

Where E is integrated Effect calculated as above and HA is Habitat Area in acres. Habitat area will be taken as the total area of the habitat potentially occupied by the biological variable as measured in the Before period. For example, effect on barnacle % cover will be multiplied by the rocky intertidal habitat area in the Before period at the Impact site. Effect will be expressed in terms of the acreage change relative to the Before period.

After five years of monitoring, the integrated effect on habitat will be calculated as:

푛

퐸푋 푡표푡푎푙 = ∑ 퐸푋푖 푖=1

Only negative impacts (i.e. not positive change) will be included in these integrated effects to obtain a conservative estimate of project impact. After five years of monitoring, the integrated change in ecological function will be calculated as:

푛

퐹푋 푡표푡푎푙 = ∑ 퐹푋푖 푖=1

Integrated effect in the case of an observed impact will be negative for all evaluation variables. Because negative effects only will be considered here, integrated effect over the 5 years on a given variable can only be negative or no change (zero effect) for that variable.

For each Habitat, loss of acre-years of Habitat itself and each associated Function will be added at the end of the 5 years to determine total impact for mitigation. However, annual assessments will also be performed to facilitate adaptive sampling and management, particularly in the case where additional activities such as renourishment and backpassing are executed. Annual assessment results may be used by the regulatory agencies to evaluate the need for adaptive mitigation and/or compensatory mitigation prior to the end of the 5 years.

An example of the above for habitat is as follows:

Rocky intertidal habitat occupies 3 acres at the Impact site in the Before period. At the Reference sites, rocky intertidal habitat occupies 1, 3, and 4 acres in the Before period. This yields delta values of 3-1=2, 3- 3=0, and 3-4=-1, yielding an average delta value of 0.33 acres. In subsequent years, delta values are calculated the same way. In year 1, the average delta is -1, in year 2 it is 0, in year 3 it is -2, in year 4 it is 1, and in year 5 it is 0. Then we use these deltas to calculate an effect for each year: year 1 = (0.33-1) = -0.66 acre, year 2 = (0.33+0) = 0.33 acre, year 3 = (0.33-2) = -1.66 acre, year 4 = (0.33+1) = 1.33 acre, year 5 = (0.33+0) = 0.33 acre. Positive changes are considered as zero change. This yields an integrated Effect of (- 0.66 + 0 - 1.66 + 0 + 0) = -2.32 acres, representing a loss of 2.32 acres of rocky intertidal habitat.

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An example for ecological function is as follows:

Mussels occupy 33% cover on the 3 acres of rocky intertidal habitat at the Impact site in the Before period. This yields 3 x 0.33 = 1-acre of mussel function. At the three Reference sites, mussels occupy 10% of 1 acre (0.1 acre), 20% of 3 acres (0.6 acre), and 40% of 4 acres (1.6 acres) in the Before period. This yields delta values of 1-0.1=0.9, 1-0.6=0.4, and 1-1.6=-0.6, yielding an average delta value of 0.23 acres. In subsequent years, delta values are calculated the same way. In year 1, the average delta is -0.2, in year 2 it is -0.3, in year 3 it is -0.4, in year 4 it is -0.2, and in year 5 it is -0.2. Then we use these deltas to calculate an effect for each year: year 1 = (0.23-0.2) = 0.03 acre, year 2 = (0.23-0.3) = -0.07 acre, year 3 = (0.23-0.4) = -0.17 acre, year 4 = (0.23-0.2) = 0.03 acre, year 5 = (0.23-0.2) = 0.03 acre. As positive values are considered no change, this yields an integrated Effect of (0 - 0.07 – 0.17 + 0 + 0) = -0.24 acres, or loss of 0.24 acres of mussel bed function.

In the above set of examples, impact on the Rocky Intertidal would be taken as the sum of impact on the habitat itself and ecological function, -2.32 – 0.24 = -2.56 acres. All remaining ecological function variables would be calculated and summed to get total impact on the habitat. Again, positive change in a given variable will be valued at zero and will not contribute to this total impact calculation. This means that if one group was replaced by another, e.g. mussels are replaced by algae, the loss of mussels would be considered an impact and would the impact would not be canceled out by the increase in algae which would be counted as zero. If this shift is not due to the activity but to natural processes, the shift should occur in the reference sites also. If the reference sites track the impact site, then the decline of mussels would match what happens at the reference sites and would not be statistically significant. Because of the range of ecological shifts possible, the nature of changes and their interpretation as impacts may be reevaluated as the project progresses, in consultation with the SAP and independent Agencies.

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

MITIGATION

ADAPTIVE MANAGEMENT State and federal agencies with jurisdiction over the Project require that adaptive measures are identified to lessen the Project’s impacts. Steps have been identified to lessen impacts through adaptively managing beach maintenance and nourishment activities. Adaptive management may occur throughout the permitted period in an attempt to minimize impacts and will be considered the first step before arriving at mitigation. The annual monitoring results will help guide adaptive management actions.

Adaptive Management Framework Project actions consist of major and minor activities on the beach. These include initial and subsequent major nourishment events of approximately 300,000 cy, periodic small scale interim nourishments involving up to 75,000 cy of sand and periodic backpassing of sand no more than once per year, all per the CCC’s CDP- authorized triggers. Maintenance activities and their associated triggers are described in detail in the AMMP (attached as Appendix C). The AMMP itself responds to CDP condition 4 ‘Final Adaptive Management and Monitoring Plan’. It is understood that regulatory agencies, both state and federal, will at least initially allow for beach nourishment using imported sand of a coarser grain size (D50 0.25 mm to 0.6 mm) than represented by the native sand along Broad Beach (D50 0.25 mm).

The State Lands lease issued for the Project identifies a number of AMMs (attached as Appendix D) designed to protect undisturbed beach habitat areas while also achieving Project objectives for ongoing beach nourishment. Such measures include:

 Minimizing aerial extent of beach disturbance (i.e. areas of excavation or fill) while maximizing sand availability for backpassing consistent with this goal and maintaining an acceptable beach profile and proportionate beach width.  Protection of contiguous areas of macro-invertebrate habitat, particularly within the lower, mid and upper intertidal zones.  Protection and retention of areas of beach wrack.  Prior to backpassing, relocation of all beach wrack from areas proposed for excavation or fill to areas that will remain undisturbed using hand crews or light equipment only.  Retention of areas of undisturbed connectivity between portions of the dune habitat and the intertidal zone.

Implementation of this MHMMP should generate information that identifies the presence/absence, and magnitude, of biotic differences between the Project area and regional reference sites. It is also expected that the MHMMP will provide insight with respect to horizontal and vertical sand movement from the constructed beach footprint.

The MHMMP, along with the physical monitoring program as approved in the final AMMP and the dune monitoring program as approved in the final DHREP, should provide insights into whether the use of coarser than native grain sand poses a risk to sensitive coastal resources. Further, the MHMMP should yield information related to the response of beach infauna to placed and migrated sand.

Beyond identified avoidance measures, a number of maintenance activity variables may be adjusted to respond to identified biological impacts with adaptive management. While this framework contemplates potential actions, agency authorization to conduct any of the actions will be required and decision making will be informed by the results of the physical, dune and marine resources monitoring. Variables that may be adjusted (within all agency permitted limits) in the adaptive management framework include:

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan

 Volume of sand backpassed at any given time;  Seasonal timing of sand nourishment or backpassing;  Location of sand placement in subsequent maintenance or nourishment activities for impact avoidance or minimization purposes;  Frequency of nourishment or maintenance actions;  Beach slope and seaward limit of nourishment or backpassing fill;  Grain size of sand used in supplemental nourishment events;  Methods of sand placement.

The framework in Table 6-1 offers some potential impact outcomes and recommendations of adaptive management actions that may be applied to lessen effects depending upon the type, nature of effects, and magnitude of signal. The list of potential actions may be updated as the Project progresses and insight from other nourishment projects in similar environments becomes available.

Table 6-1: Potential Adaptive Management Actions

Habitat Condition Possible Adaptive Management Action

 Reduction of grain size D50 in supplemental nourishments of the beach;  Blend beach materials in back passing events or supplement higher elevation beach with finer sands Failure to develop similar to enhance upper beach biota; and/or Supratidal abundance or richness conditions as native beach environments  Review beach topology for potential to alter slopes in a manner that would enhance beach performance through; 1) increased wrack collection; 2) improved beach gradients through biotically underrepresented areas.  Adjust seasonal timing of nourishment, backpassing, or other maintenance (eg. of revetment); Beach habitat fails to develop or  Reassess beach response after additional colonization sustain abundance and richness event periods; conditions similar to native beaches  Adjust location or reduce scale of beach activities, and disturbance activities appear to including consideration of staggered or phased work be causal factors based on sampling that would leave portions of the beach and disturbance timing. unmanipulated for longer periods; and/or  Consider altering grain size of sand in portions of the Intertidal beach to create refugia, or consider reducing grain size with future nourishment events.  Relocate future backpassing or nourishing events further to the east to minimize sand capture by the Sand migrates into Lechuza Cove cove; and persists for an extended period  Use of reduced grain size D sand at the west end of due to the increased sand grain size 50 the approved footprint so that sand dynamics are and increased energy needed to more similar to natural conditions in the vicinity of purge sand from the cove. Lechuza Cove; and/or

 Alter the shape of the west end of the beach to minimize westerly mobility of the beach,

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Habitat Condition Possible Adaptive Management Action  Evaluate potential to relocate fills in future maintenance or back passing events;  Consider reducing volumes in the beach area; Sand travels offshore from the  Consider altering the beach construction schedules to avoid stormy periods early in the beach placement; Subtidal beach to nearshore waters. and/or  Consider altering the beach slope to flatten beach slopes and increase shoreline holding capacity for sand.

Adaptive management actions should be considered in full light of the on-going monitoring programs and how the actions may affect any of the current programs, as well as the physical performance of the beach relative to other Project objectives, such as ensuring public access. COMPENSATORY MITIGATION It is anticipated that Project impacts will be pulsed through time with the first placement generating the greatest potential risk for impacts as it will not have benefit of adaptive management and is based purely on modeling results rather than empirical monitoring. Over time, the adaptive management program and normal sand movement patterns will hopefully result in reductions of any impacts. Monitoring results at the 5-year post-nourishment evaluation period will inform permitting agencies as they make determinations regarding potential compensatory mitigation requirements should Project-caused impacts be identified. Mitigation sites will be situated in waters similar to the proposed Project site within the littoral cell to the fullest extent practicable, however alternative mitigation options outside the littoral cell may be considered by the CCC.

Adverse impacts that may arise from this Project are identified as including the following:

 Reduction in area or quality of supratidal, intertidal, and subtidal habitats including hard substrate availability as well as the condition of associated biological communities (e.g., species diversity and abundances)  Reduction in sand beach habitat quality  Reduction in subtidal soft bottom habitat quality  Reduction in area or quality of surfgrass  Reduction in area or quality of eelgrass  Reduction in area or quality of kelp beds

The methods selected for compensatory mitigation will be dependent upon a number of factors including:

 Nature and scale of impacts over time;  Mitigation opportunities available to the Project at the time of mitigation needs;  Capacity to address future impacts by Project adaptive management activities, and;  Regulatory agency approval of the mitigation program structure considering permanent or adaptive management options. HABITAT SPECIFIC MITIGATION PLAN Per CDP Special Condition 6E, upon detection of adverse impacts to one or more habitats, the BBGHAD, in consultation with the SAP and agencies, shall develop a habitat-specific mitigation plan for each impacted habitat that will provide the overall framework to guide the compensatory mitigation work. Habitat-specific

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Final Broad Beach Marine Habitat Monitoring and Mitigation Plan mitigation plans must be reviewed and approved by the CCC Executive Director. Any revised mitigation and monitoring program shall be processed as an amendment to the CDP, unless the CCC Executive Director determines that no permit amendment is required.

CCC Mitigation Ratios This section addresses CCC requirements only with Corps requirements addressed separately in section 6.3.4 and further detailed in the Conceptual Habitat Compensatory Mitigation Plan, Broad Beach and Dune Restoration Project, Michael Baker International (July 2017) provided as Appendix B.

The CDP notes that, if adverse impacts are detected, compensatory mitigation will be required. The mitigation ratio for impacts upon subtidal rocky or intertidal rocky habitat is specified at a minimum of 4:1 because of the uncertainty and difficulty of mitigating for these habitats. The CDP also specifies that adverse impacts upon eelgrass shall be mitigated according to the CEMP. Other habitats and resources being monitored (e.g., beaches, soft bottom subtidal areas, surfgrass) not specified in Special Condition 6E are not excluded from mitigation requirements, rather they simply have no a priori prescription for ratios. All final mitigation ratios will be determined in the future, as-needed and appropriate in each habitat-specific mitigation plan following SAP and agency consultation, and review and approval by the CCC. Compensatory Mitigation Opportunities Compensatory mitigation for marine habitat impacts will potentially be implemented via fund contributions to appropriate parties identified in Table 6-2. Payments would be made with the intent that mitigation would be implemented by the pre-approved parties. The notification would include the impacts that occurred, proposed party to receive the payment, and the party (ies) mitigation proposal/site location. This section presents some potential options for compensatory opportunities although it should be noted that inclusion of any opportunities here does not represent approval by the CCC.

Mitigation opportunities identified by these mitigation-responsible parties are currently focusing on mitigation through restoration of various habitat resources including, but not limited to:

 Mussel habitat  Surfgrass habitat  Artificial reef habitat  Eelgrass habitat  Abalone restoration

Working with the Corps, the BBGHAD has identified mitigation party(ies) which may receive funding from the BBGHAD once adaptive management is exhausted. These parties are composed of various restoration programs and are presented in Table 6.2. The mitigation concepts were suggested by the Corps. Should compensatory mitigation be required by the CCC at any time, the BBGHAD will prepare habitat-specific mitigation plan(s) in accordance with CDP Special Condition 6E and as discussed in Section 6.3.1, above. Such habitat-specific mitigation plan(s) will specify proposed mitigation frameworks, actions, and monitoring plans for the review and approval of the CCC.

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Table 6-2: Mitigation Parties

Primary Habitat Mitigation Party* Point of Contact Kristin de Nesnera Mussel RC Lab at UCSC [email protected] Heather Burdick P.O. Box 13336 Abalone The Bay Foundation Los Angeles, CA 90013 [email protected] Dr. Jennifer Caselle UCSB Marine Science Institute Kelp Bed/Artificial Reef Marine Science Institute UCSB Santa Barbara, CA 93106-6150 Enhancement [email protected] (805) 893-5144 D. C. Reed Marine Science Institute at Surfgrass Santa Barbara, CA 93106, U.S.A. UCSB [email protected] Sara Briley Marine Restoration Director Eelgrass Orange County Coastkeeper F #110, 3151 Airway Ave Costa Mesa,CA 92626 [email protected] Laura Anderson Algae RC Lab at UCSC [email protected] Richard F. Ambrose Ambrose Lab University of Rocky Intertidal [email protected] California Los Angeles (310) 825-6144 * Potential options for compensatory opportunities shown, inclusion of these opportunities does not represent approval by the regulatory agencies. A formal Memorandum of Understanding between the BBGAD and one or more of the above parties would be executed prior to formal mitigation coordination. Functions and Values of Habitat Types(s) To Be Rehabilitated, Enhanced and/or Preserved Functions and values of the mitigation site will vary with the selected habitats included in the mitigation program. Anticipated functions and values are discussed by mitigation type, below.

Eelgrass Habitat Restored eelgrass habitat (Zostera pacifica) is anticipated to function similarly as natural eelgrass habitat in terms of fish and shellfish habitat (including nursery and adult structured habitat for fish and invertebrates) within 3 years of restoration. A responsible party identified for potentially ensuring successful restoration of eelgrass habitat is Orange County Coastkeeper. In the event that impacts occur, eelgrass habitat would preliminarily be mitigated at 1.4:1 (in the event that Zostera marina is accepted as mitigation for Zostera pacifica). The final ratio would be defined in the habitat specific mitigation plan once the actual impacts are defined. Costs for the restoration and enhancement of each habitat type are defined in Section 6.3.7. All functions of eelgrass beds are typically recaptured, inclusive of delays, by year 5 at CEMP mitigation ratios, provided implementation commences concurrent with identified losses. CEMP addresses delays in commencement of restoration.

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Surfgrass Restored surfgrass habitat is anticipated to function similarly to natural surfgrass habitat in terms of fish and shellfish habitat (including nursery and adult structured habitat for fish and invertebrates). A responsible party for potentially ensuring successful restoration of surfgrass habitat could be the UC Santa Barbara Marine Science Institute. Surfgrass provides refuge habitat within the rocky intertidal and provides shade and moisture trapping habitat at low tides aiding to the protection of invertebrates. It also protects against scour, traps detritus and sand and retains vegetative cover in a fluctuating sanded environment. Surfgrass functions can be developed within approximately 3 to 4 years by vegetative expansion although examples of attempted restoration are rare, with successes being even more so (Wyllie-Echeverria et al. 2015). The restoration efforts conducted have demonstrated the capabilities to restore surfgrass at a research scale. However, none of the projects have attempted restoration at a scale comparable to the numerous eelgrass restoration projects and thus transplants for compensatory mitigation functions remain risky.

Kelp Bed/Rocky Reef Enhancement Impacts to rocky subtidal habitat may be mitigated through enhancement of other rocky habitat, including reduction of detrimental organisms from these environments. A potential responsible party for potentially ensuring successful restoration of kelp bed/rocky reef enhancement could be the UCSB Marine Science Institute. Enhancement may include urchin removal to restore kelp to urchin barrens. Abalone restoration through propagation and outplanting activities could also be considered and are discussed in Section 6.3.3.5. This work would provide for recovery of a richer algal community inclusive of giant kelp that provides wave dampening, production export, and nutrient transformation. Removal will also reduce competition for nutrients and space (rock crevices) for abalone populations. A richer structured community would also benefit fish and invertebrate diversity on the reefs through increasing structure and primary productivity. Kelp forest development also enhances intertidal habitat functions by feeding detritus to the wrack line on beaches, dampening wave impacts, and stabilizing beaches in a manner that reduces erosion and sediment transport as well as subsidizing intertidal reef communities with particulate organic matter.

Rocky Intertidal Habitat Enhancement at Broad Beach A responsible party for potentially ensuring successful restoration of rocky intertidal habitat enhancement may be the Ambrose Lab at the University of California, Los Angeles. Native rock can be configured to create cracks and crevices to provide abalone habitat and at the correct elevations, can also support mussel and barnacle beds. These rocks could be derived from selective harvesting of suitable rock. Placed rock would be of a scale large enough to remain stable under storm forces, to rise above the scoured elevations that presently affects the boulder field and limit habitat development and persistence in this area. Such enhancement would contribute functionally to the diversity, persistence, and abundance of rocky intertidal biota (inclusive of algal and invertebrate resources). Depending upon where rock is placed, this substrate may also contribute to opportunities to expand surfgrass as mitigation for impacts to this resource or other rocky shore resources.

Abalone A responsible party for potentially ensuring successful restoration of abalone could be The Bay Foundation. Quality habitat would be created to restore abalone populations. Restoration would ideally be in conjunction with kelp forest restoration and intertidal rocky habitat enhancement, which are both considered vital habitat for abalone. Restoration activities may include enhancement of rocky sand interface, which can increase the rate of abalone contact with negatively buoyant drift algae. Efforts towards restoration may explore techniques for spawning, rearing, and outplanting native abalone species. Restoring abalone populations is vital in controlling algal populations and decreasing the chance for algal blooms in the ocean. In addition to keeping sea urchin populations level by competition for space and food.

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Mussels Quality habitat will be created to restore mussel populations. A potential responsible party for ensuring successful restoration of mussel is the Raimondi-Carr Lab at UCSC. Restoration of mussels would be considered as a means to enhance function of intertidal environments. Restoration of rocky intertidal habitat will involve development of rocky substrate surfaces for mussel bed establishment. As such, mussel habitat will be created as a result of rocky intertidal habitat restoration. Mussels provide key roles in marine environments, removing phytoplankton and bacteria from the water. Their shells provide important substrate for algae and insect larvae attachment.

Algae Quality habitat will be created to restore algal populations. A potential responsible party for ensuring successful restoration of algae is the Raimondi-Carr Lab at UCSC. Algal restoration may involve the transplant of live juveniles and large reproductive adults onto horizontal and partially shaded north-facing vertical surfaces at target locations where desiccation and trampling stress are reduced. This would establish an adult population and can serve as a methodology to naturally seed the location. Such methods have proven to be less expensive and not labor intensive. In addition, algal restoration would also be considered as a means to enhance function of intertidal environments. As such, algal habitat would be created as a result of rocky intertidal habitat restoration. The functionality of algae presence has been shown to moderate substrate temperature, provide spatial and desiccation refuge, and facilitate community complexity.

Other Mitigation Considerations The Corps has separately required the development of an advanced conceptual mitigation plan to offset potential impacts which may occur and be identified though the implementation of this MHMMP. This plan entitled “Conceptual Habitat Compensatory Mitigation Plan Broad Beach” (Michael Baker International 2017) is provided as Appendix B. The Corps mitigation plan identifies ratios for marine habitat impacts and mitigation amounts for impacts related to construction of the 2010 emergency revetment. After reviewing all monitoring data and analysis, the Corps will make an independent assessment regarding impacts and the need for additional compensatory mitigation using its own procedures (such as 12501-SPD Standard Operating Procedure for Determination of Mitigation Ratios).

For Corps purposes, mitigation will generally be pursued in a stepwise process of considering in-kind mitigation as a preferred mitigation methodology, followed by out-of-kind mitigation. To the extent that impacts are small and to lesser value habitats, consideration will be given to mitigation of impacts with higher value mitigation at a lesser mitigation ratio (e.g., scoured boulder/cobble may potentially be mitigated by expansion of persistent reef, kelp bed, or surfgrass habitat). Further, low levels of impact to multiple habitats may potentially be accumulated and mitigated as a single mitigation effort undertaken by valuing and scaling the individual impact types and extents to the type of mitigation proposed.

Time Lapse Between Impacts And Expected Mitigation Success Prior to making a payment to the one or more parties above, prior milestones will have been met and a determination (by the Corps and other resource agencies) made that compensatory mitigation must be initiated. Milestones include:

1. Annual monitoring of Project site and adjacent habitats pursuant to permit requirements and the monitoring plan outlined in earlier sections of this document. 2. Adverse impacts are noted to be on the rise and/or have occurred. 3. Adaptive management has been initiated in an attempt to reduce ongoing impacts. 4. Continued tracking of the losses and gains to the end of the permitted period monitoring mark. Tracking and monitoring shall be conducted pursuant to the approved monitoring plan and

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guidance of the SAP. Depending on if/when a 2nd major renourishment is planned, the Corps may need to make a determination regarding compensatory mitigation prior to the 5-year anniversary of initial project impacts. 5. Upon reaching the 5-year mark, total losses/gains would be calculated for the past five years. Should a net loss or “deficit” occur, the acreage of the net loss would be recorded. 6. The resource agencies would determine the impacts that require compensatory mitigation including the amount(s) and type(s) required. 7. The BBGHAD would then make a mitigation payment to the appropriate responsible party.

Payment to the specific party responsible for each mitigation project would be made once the acreage and funds is confirmed with the Corps. Implementation and use of the funds would be the responsibility of the party responsible for mitigation. Responsible Parties The BBGHAD shall be the responsible implementing party for any required mitigation.

Applicant Name: Broad Beach Geologic Hazard Abatement District 2049 Century Park East, Ste 2700, Los Angeles, California 90067 Contact: Mr. Kenneth Ehrlich Phone: (310) 746-4412

Estimated Mitigation Cost The BBGHAD shall provide payment to the mitigation party (ies). A summary of an approximation of costs for mitigation of each resource is provided below.

 Eelgrass: Eelgrass restoration can range from approximately $90,000 per acre to $202,343 per acre according to NOAA’s Coastal Ocean Program (Fonseca et al, 1998). A recent review of the Upper Newport Bay Eelgrass Restoration Project found that eelgrass restoration costs approximated $110,091 per acre (Coastal Conservancy, 2011). Eelgrass transplant approximated $50,000 (Corps 1982).  Surfgrass: Surfgrass restoration can range from approximately $250,000 for surfgrass transplant and approximately $2,000,000 per acre for surfgrass habitat creation (Corps 2015).  Kelp Forest Enhancement: A recent review of the Montrose Settlements Restoration Program indicated that kelp forest enhancement costs can be approximated at $70,000 per acre (Montrose Settlements Restoration Program, 2005). Kelp transplant approximated $50,000 per acre for the San Clemente Shoreline Protection Project (CDFW 2011). Final costs would ultimately depend on the techniques and intensity used to establish the kelp.  Reef Habitat: A recent review of the San Clemente Shoreline Protection Project indicated that shallow water reef design and construction approximated $2 million per acre and deep water reef construction approximated $500,000 per acre (CDFW 2011).  Abalone: Abalone restoration costs can range from approximately $158,000 per acre (400 linear meters) at year one to $383,000 per acre at year ten. This cost estimate includes post remediation sampling for performance. (Dr. Pete Raimondi, personal communication, 2017).  Algae: Algal restoration costs are anticipated at approximately $203,000 per linear meters (Dr. Pete Raimondi, personal communication, 2017).  Mussel: Mussel bed restoration costs are anticipated at approximately $240,000 per 500 linear meters of shoreline. This cost estimate includes post remediation sampling for performance. (Dr. Pete Raimondi, personal communication, 2017).  Intertidal Rocky Habitat: Intertidal Rocky Habitat restoration costs are anticipated to be in conjunction with mussel and abalone restoration. Thus costs will be included.

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APPENDIX A

Special Condition 6 Language,

Notice of Intent to Issue Permit, 4-15-0390

California Coastal Commission

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APPENDIX B

Conceptual Habitat Compensatory Mitigation Plan

Broad Beach and Dune Restoration Project,

Michael Baker International (July 2017)

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APPENDIX C

Adaptive Management and Monitoring Plan

Moffatt & Nichol, 2017

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APPENDIX D

Exhibit E, Monitoring Implementation Program

General Lease – Beach Replenishment and Protective Structure Use,

Broad Beach Restoration Project

California State Lands Commission, 2016

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