APPENDIX F Marine Biological Resources Technical Report Marine Biological Resources Technical Report for the Buena Vista Lagoon Enhancement Project FINAL Prepared for: AECOM 1420 Kettner Boulevard, Suite 500 San Diego CA 92101 Prepared by: Merkel & Associates, Inc. 5434 Ruffin Road San Diego, CA 92123 Phone: (858) 560-5465 Fax: (858) 560-7779 August 2014 Buena Vista Lagoon Enhancement Project Marine Biological Resources Technical Report August 2014 TABLE OF CONTENTS 1.0 INTRODUCTION ..................................................................................................................... 1 1.1 Technical Approach ........................................................................................................ 1 1.2 Project Location and Lagoon Restoration Overview ...................................................... 1 1.3 Project Alternatives ......................................................................................................... 2 1.4 Freshwater Alternative .................................................................................................... 5 1.5 Saltwater Alternative ...................................................................................................... 9 1.6 Hybrid Alternative .......................................................................................................... 9 1.7 No Project Alternative .................................................................................................. 10 1.8 Materials Disposal/Placement ....................................................................................... 15 1.9 Construction Methods, Schedule, and Design Features................................................ 21 2.0 EXISTING CONDITIONS ..................................................................................................... 25 2.1 Regional Overview ....................................................................................................... 25 2.2 Marine Shoreline and Offshore Habitats ...................................................................... 26 2.3 Plankton ........................................................................................................................ 40 2.4 Marine-Associated Birds .............................................................................................. 40 2.5 Marine Mammals .......................................................................................................... 42 2.6 Threatened and Endangered Species ............................................................................ 42 2.7 Coastal Lagoons ............................................................................................................ 45 2.8 Receiver Sites................................................................................................................ 48 2.9 Nearshore Disposal Site ................................................................................................ 51 3.0 IMPACT ANALYSIS ............................................................................................................. 52 3.1 Freshwater Alternative .................................................................................................. 52 3.2 Saltwater Alternative .................................................................................................... 62 3.3 Hybrid Alternative – Options A and B ......................................................................... 68 4.0 SUMMARY ............................................................................................................................ 76 5.0 REFERENCES ........................................................................................................................ 79 LIST OF FIGURES Figure 1-1. Regional Map. ..................................................................................................................... 3 Figure 1-2. Project Location and Existing Habitat Distribution Map. ................................................... 4 Figure 1-3. Proposed Freshwater Alternative Habitat Distribution. .................................................... 11 Figure 1-4. Proposed Saltwater Alternative Habitat Distribution. ....................................................... 12 Figure 1-5. Proposed Hybrid Alternative Option A Habitat Distribution. ........................................... 13 Figure 1-6. Proposed Hybrid Alternative Option B Habitat Distribution. ........................................... 14 Figure 1-7. Potential Offsite Materials Placement Sites. ..................................................................... 18 Figure 1-8. Oceanside Nearshore and Beach Placement Sites. ............................................................ 19 Figure 1-9. North Carlsbad Placement Site. ........................................................................................ 20 Figure 2-1. Nearshore resources and proposed receiver sites within the study area (from SANDAG 2011). ........................................................................................................................................... 33 Figure 2-2. Sensitive habitats and nearshore resources in vicinity of proposed nearshore disposal footprint and Oceanside receiver site (after SANDAG 2011). .................................................... 34 Figure 2-3. Sensitive habitats and nearshore resources in vicinity of North Carlsbad receiver site (from SANDAG 2011). ............................................................................................................... 35 Merkel & Associates, Inc. #11-077-01 i Buena Vista Lagoon Enhancement Project Marine Biological Resources Technical Report August 2014 LIST OF TABLES Table 1-1. Existing and Proposed Habitat Distribution (Acreages). ...................................................... 6 Table 1-2. Hydraulic Connection Summary. ......................................................................................... 7 Table 1-3. Materials Removal and Maintenance Requirements. ........................................................... 8 Table 1-4. Earthwork Volume (cy) by Basin. ...................................................................................... 15 Table 1-5. Estimated Sand Content Percentage by Basin. ................................................................... 16 Table 1-6. Materials Disposal and Reuse Scenarios. ........................................................................... 17 Table 2-1. Common organisms observed from soft bottom habitat in San Diego County. ................. 29 Table 2-2. Estimated hard-bottom and vegetated habitat acreage in the vicinity of the study area (from SANDAG 2011). ............................................................................................................... 30 Table 2-3. Kelp canopy coverage (acres) of San Diego County kelp beds from 2000 to 2011. .......... 31 Table 2-4. Common organisms observed from hard bottom reefs in San Diego County. ................... 37 Table 2-5. Birds observed along the shoreline within the Encinitas and Solana Beach study area, September 2002 (from USACE 2012). ........................................................................................ 41 Table 2-6. Status of Least Tern Breeding in the vicinity of the study area, 2009-2012. ..................... 44 Table 2-7. Results of summer window surveys for snowy plovers in the vicinity of the study area, 2006-2012. ................................................................................................................................... 44 Table 2-8. Estimated closest distances to hard bottom and vegetated habitats from the seaward boundary of proposed receiver sites (from SANDAG 2011). ..................................................... 48 Table 2-9. Estimated closest distances to least tern and snowy plover nest sites (from SANDAG 2011). ........................................................................................................................................... 49 Table 2-10. Summary of habitats at the proposed receiver sites and in the nearshore vicinity (from SANDAG 2011). ......................................................................................................................... 49 Table 3-1. Estimated direct impact acreage with proposed sand placement per approach for Freshwater Alternative. ............................................................................................................... 54 Table 3-2. Estimated sediment plume length at potential disposal sites (after SANDAG 2011). ....... 57 Table 3-3. Estimated direct impact acreage with proposed sand placement per approach for Saltwater Alternative. .................................................................................................................................. 63 Table 3-4. Estimated direct impact acreage with proposed sand placement per approach for Hybrid Alternative – Options A and B. ................................................................................................... 69 Merkel & Associates, Inc. #11-077-01 ii Buena Vista Lagoon Enhancement Project Marine Biological Resources Technical Report August 2014 1.0 INTRODUCTION 1.1 TECHNICAL APPROACH This report specifically addresses shoreline and nearshore marine biological resources to a depth of approximately 100 ft between Oceanside Harbor and Agua Hedionda Lagoon. Biological resources within Buena Vista Lagoon are discussed and analyzed