Loading...
HomeMy WebLinkAbout; ; Beach Replenishment Carlsbad Environmental; 1997-05-01ENVIRONMENTAL ASSESSMENT FOR BEACH REPLENISHMENT AT NORTH CARLSBAD, SOUTH CARLSBAD, ENCINITAS, AND TORREY PINES May 1997 Southwest Division U.S. Department of the Navy LIST OF ACRONYMS ACOE APCD BRAC CA CCD CCSTWS CDFG CEQ CFR cm CWA cy dBA DGPS dia EA EIS EJ EPA ESA FONSI FRH ft in km LCP LUP m•>m~ m3 m3/m mi jam MSL NASNI NEPA NMFS NOAA ppm ROD RWQCB SANDAG SDG&E SPCC sq SR USFWS yd2 Army Corps of Engineers Air Pollution Control District Base Realignment and Closure Cooperative Agreement Coastal Consistency Determination Coast of California Storm and Tidal Waves Study California Department of Fish and Game Council on Environmental Quality Code of Federal Regulations centimeter Clean Water Act cubic yards A-weighted decibels Differential Geographic Positioning System diameter Environmental Assessment Environmental Impact Statement Environmental Justice Environmental Protection Agency Endangered Species Act Finding Of No Significant Impact Frederic R. Harris, Inc. feet inches kilometers Local Coastal Program Land Use Plan meters square meter cubic meters cubic meters per meter miles micrometers Mean Sea Level Naval Air Station North Island National Environmental Policy Act National Marine Fisheries Sesrvice National Oceanic and Atmospheric Administration parts per million Record of Decision Regional Water Quality Control Board San Diego Association of Governments San Diego Gas & Electric Spill Prevention Control and Counter-Measure Plan square State Route U.S. Fish and Wildlife Service square yard a-l 211603000 ENVIRONMENTAL ASSESSMENT FY97 BEACH REPLENISHMENT AT NORTH CARLSBAD, SOUTH CARLSBAD, ENCINITAS, AND TORREY PINES, CALIFORNIA ABSTRACT The Department of the Navy has prepared an Environmental Assessment (EA) to analyze the placement of dredged material on beaches in North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines, or as an alternative at Buccaneer Beach in South Oceanside for beach replenishment. This action is being undertaken to accommodate the disposal of dredged material as a result of dredging operations in San Diego Bay for the homeporting of a NIMITZ class aircraft carrier and to comply with the San Diego Association of Government's Shoreline Preservation Strategy for the San Diego Region (SANDAG 1993). The proposed action is scheduled to be implemented starting July 1997. This document is intended to be a "tiered" EA based on analyses provided in the Environmental Impact Statement for the Development of Facilities in San Diego/Coronado for the Homeporting of One NIMITZ Class Aircraft Carrier (Navy 1995a). Due to subsequent changes in the location of receiver beaches, as identified in the Environmental Impact Statement (EIS), the EA evaluates the potential effects of beach replenishment and associated operations (e.g., barge placement, sediment disposal, and grading) at the proposed receiver sites and addresses the following site-specific environmental issues: geology and soils, coastal wetlands, water resources, biology, land use and recreation, safety and environmental health, aesthetics, utilities, and noise. Prepared by: U.S. Department of the Navy Cooperating Agency: U.S. Army Corps of Engineers, Los Angeles District Point of Contact: Mr. Patrick McCoy Southwest Division Naval Facilities Engineering Command 1220 Pacific Highway San Diego, California 92132-5190 (619) 556-8706 May 1997 211603000 AB-1 This Page Intentionally Left Blank AB-2 211603000 TABLE OF CONTENTS SECTION TITLE PAGE LIST OF ACRONYMS a-1 ABSTRACT AB-1 EXECUTIVE SUMMARY ES-1 1 INTRODUCTION 1-1 1.1 Background 1-1 1.2 Purpose and Need 1-4 1.3 Location of the Proposed Action 1 -6 1.4 Relevant Federal, State, and Local Statutes, Regulations, and Guidelines 1-8 1.5 Interagency Coordination 1-21 2 DESCRIPTION OF THE PROPOSED ACTION AND ALTERNATIVES 2-1 2.1 Alternative Selection Criteria 2-1 2.2 Proposed Action - Beach Replenishment 2-3 2.3 Alternatives Considered 2-9 2.3.1 Buccaneer Beach/South Carlsbad Alternative 2-9 2.3.2 Torrey Pines Design Alternative 2-10 2.3.3 Agua Hedionda Alternative 2-10 2.3.4 South Encinitas Alternative 2-17 2.3.5 San Elijo State Beach Alternative 2-17 2.3.6 Del Mar Alternative 2-18 2.3.7 Torrey Pines Design Alternative 2-18 2.3.8 Black's Beach Alternative 2-18 2.3.9 Scripp's Alternative 2-20 2.4 No Action Alternative 2-20 3 AFFECTED ENVIRONMENT 3-1 3.1 Geology and Soils 3-1 3.1.1 Definition of Resource 3-1 3.1.2 North Carlsbad 3-1 3.1.2.1 Coastal Geology 3-1 3.1.2.2 Littoral Processes 3-2 211603000 i TABLE OF CONTENTS (Continued) SECTION TITLE PAGE 3.1.3 South Carlsbad 3-4 3.1.3.1 Coastal Geology 3-4 3.1.3.2 Littoral Processes 3-4 3.1.4 Encinitas 3-4 3.1.4.1 Coastal Geology 3-4 3.1.4.2 Littoral Processes 3-5 3.1.5 Torrey Pines 3-5 3.1.5.1 Coastal Geology 3-5 3.1.5.2 Littoral Processes 3-5 3.1.6 Buccaneer Beach/South Carlsbad Alternative 3-6 3.1.6.1 Coastal Geology 3-6 3.1.6.2 Littoral Processes 3-6 3.2 Coastal Wetlands 3-6 3.2.1 Definition of Resource 3-6 3.2.2 San Luis Rey River 3-7 3.2.3 Loma Alta Creek 3-7 3.2.4 Buena Vista Lagoon 3-7 3.2.5 Agua Hedionda Lagoon 3-8 3.2.6 Encinas Creek 3-9 3.2.7 Batiquitos Lagoon 3-9 3.2.8 San Elijo Lagoon 3-10 3.2.9 San Dieguito Lagoon 3-10 3.2.10 Los Penasquitos Lagoon 3-11 3.3 Water Resources 3-12 3.3.1 Definition of Resource 3-12 3.3.2 Physical Processes 3-12 3.3.3 Chemical Properties 3-13 3.3.4 Turbidity 3-13 3.4 Biology 3-14 3.4.1 Definition of Resource 3-14 3.4.2 North Carlsbad 3-15 3.4.3 South Carlsbad 3-21 3.4.4 Encinitas 3-22 ii 211603000 TABLE OF CONTENTS (Continued) SECTION TITLE PAGE 3.4.5 Torrey Pines 3-27 3.4.6 Buccaneer Beach/South Carlsbad Alternative 3-28 3.5 Land Use and Recreation 3-31 3.5.1 Definition of Resource 3-31 3.5.2 North Carlsbad 3-32 3.5.3 South Carlsbad 3-34 3.5.4 Encinitas 3-35 3.5.5 Torrey Pines 3-36 3.5.6 Buccaneer Beach/South Carlsbad Alternative 3-37 3.6 Safety and Environmental Health 3-38 3.6.1 Definition of Resource 3-38 3.6.2 North Carlsbad 3-39 3.6.3 South Carlsbad 3-39 3.6.4 Encinitas 3-39 3.6.5 Torrey Pines 3-39 3.6.6 Buccaneer Beach/South Carlsbad Alternative 3-40 3.7 Aesthetics 3-40 3.7.1 Definition of Resource 3-40 3.7.2 North Carlsbad 3-40 3.7.3 South Carlsbad 3-41 3.7.4 Encinitas 3-41 3.7.5 Torrey Pines 3-41 3.7.6 Buccaneer Beach/South Carlsbad Alternative 3-45 3.8 Structures and Utilities 3-49 3.8.1 Definition of Resource 3-49 3.8.2 North Carlsbad 3-49 3.8.2.1 Access Stairs 3-49 3.8.2.2 Storm Drains 3-49 3.8.2.3 Sea Walls 3-51 3.8.3 South Carlsbad 3-51 3.8.3.1 Access Stairs 3-51 3.8.4 Encinitas 3-51 3.8.4.1 Access Stairs 3-51 211603000 iii TABLE OF CONTENTS (Continued) SECTION TITLE PAGE 3.8.4.2 Storm Drains 3-54 3.8.4.3 Sea Walls 3-54 3.8.5 Torrey Pines 3-54 3.8.6 Buccaneer Beach/South Carlsbad Alternative 3-54 3.8.6.1 Access Stairs 3-54 3.9 Noise 3-56 3.9.1 Definition of Resource 3-56 3.9.2 North Carlsbad 3-56 3.9.2.1 Noise Measurements 3-56 3.9.2.2 Noise Ordinances 3-58 3.9.3 South Carlsbad 3-58 3.9.3.1 Noise Measurements 3-58 3.9.3.2 Noise Ordinances 3-59 3.9.4 Encinitas 3-60 3.9.4.1 Noise Measurements 3-60 3.9.4.2 Noise Ordinances 3-61 3.9.5 Torrey Pines 3-62 3.9.5.1 Noise Measurements 3-62 3.9.5.2 Noise Ordinances 3-63 3.9.6 Buccaneer Beach/South Carlsbad Alternative 3-64 3.9.6.1 Noise Measurements 3-64 3.9.6.2 Noise Ordinances 3-65 4 ENVIRONMENTAL CONSEQUENCES 4-1 4.1 Geology and Soils 4-1 4.1.1 Approach to Analysis 4-1 4.1.2 North Carlsbad 4-2 4.1.2.1 Coastal Geology 4-2 4.1.2.2 Littoral Processes 4-4 4.1.3 South Carlsbad 4-5 4.1.3.1 Coastal Geology 4-5 4.1.3.2 Littoral Processes 4-5 4.1.4 Encinitas 4-7 iv 211603000 TABLE OF CONTENTS (Continued) SECTION TITLE PAGE 4.1.4.1 Coastal Geology 4-7 4.1.4.2 Littoral Processes 4-9 4.1.5 Torrey Pines 4-9 4.1.5.1 Coastal Geology 4-9 4.1.5.2 Littoral Processes 4-11 4.1.6 Buccaneer Beach/South Carlsbad Alternative 4-11 4.1.6.1 Coastal Geology 4-11 4.1.6.2 Littoral Processes 4-12 4.2 Coastal Wetlands 4-15 4.2.1 Approach to Analysis 4-15 4.2.2 North Carlsbad 4-15 4.2.2.1 Loma Alta Creek 4-15 4.2.2.2 Buena Vista Lagoon 4-16 4.2.3 South Carlsbad 4-16 4.2.3.1 Encinas Creek 4-17 4.2.4 Encinitas 4-17 4.2.4.1 Encinas Creek 4-17 4.2.4.2 Batiquitos Lagoon 4-18 4.2.5 Torrey Pines 4-19 4.2.5.1 Los Penasquitos Lagoon 4-19 4.2.6 Buccaneer Beach/South Carlsbad Alternative 4-20 4.2.6.1 San Luis Key River 4-21 4.2.6.2 Loma Alta Creek 4-21 4.2.6.3 Buena Vista Lagoon 4-22 4.3 Water Resources 4-22 4.3.1 Approach to Analysis 4-22 4.3.2 Chemical Properties 4-23 4.3.3 Turbidity 4-23 4.4 Biology 4-25 4.4.1 Approach to Analysis 4-25 4.4.2 North Carlsbad 4-25 4.4.2.1 Sand Deposition 4-25 4.4.2.2 Barge Placement and Anchoring 4-28 211603000 v TABLE OF CONTENTS (Continued) SECTION TITLE PAGE 4.4.2.3 Coastal Wetlands 4-29 4.4.3 South Carlsbad 4-29 4.4.3.1 Sand Deposition 4-29 4.4.3.2 Barge Placement and Anchoring 4-31 4.4.3.3 Coastal Wetlands 4-31 4.4.4 Encinitas 4-32 4.4.4.1 Sand Deposition 4-32 4.4.4.2 Barge Placement and Anchoring 4-33 4.4.4.3 Coastal Wetlands 4-34 4.4.5 Torrey Pines 4-34 4.4.5.1 Sand Deposition 4-34 4.4.5.2 Barge Placement and Anchoring 4-36 4.4.5.3 Coastal Wetlands 4-36 4.4.6 Buccaneer Beach/South Carlsbad Alternative 4-36 4.4.6.1 Sand Deposition 4-36 4.4.6.2 Barge Placement and Anchoring 4-38 4.4.6.3 Coastal Wetlands 4-38 4.5 Land Use and Recreation 4-39 4.5.1 Approach to Analysis 4-39 4.5.2 North Carlsbad 4-39 4.5.3 South Carlsbad 4-40 4.5.4 Encinitas 4-41 4.5.5 Torrey Pines 4-41 4.5.6 Buccaneer Beach/South Carlsbad Alternative 4-42 4.6 Safety and Environmental Health 4-43 4.6.1 Approach to Analysis 4-43 4.6.2 Proposed Beach Receiver Sites 4-43 4.7 Aesthetics 4-44 4.7.1 Approach to Analysis 4-44 4.7.2 Proposed Beach Receiver Sites 4-44 4.8 Structures and Utilities 4-45 4.8.1 Approach to Analysis 4-45 4.8.2 North Carlsbad 4-45 vi 211603000 TABLE OF CONTENTS (Continued) SECTION TITLE PAGE 4.8.2.1 Access Stairs 4-45 4.8.2.2 Storm Drains 4-46 4.8.2.3 Sea Walls 4-46 4.8.3 South Carlsbad 4-46 4.8.3.1 Access Stairs 4-46 4.8.4 Encinitas 4-47 4.8.4.1 Access Stairs 4-47 4.8.4.2 Storm Drains 4-47 4.8.4.3 Sea Walls 4-48 4.8.5 Torrey Pines 4-48 4.8.6 Buccaneer Beach/South Carlsbad Alternative 4-48 4.8.6.1 Access Stairs 4-48 4.9 Noise 4-48 4.9.1 Approach to Analysis 4-48 4.9.2 North Carlsbad 4-49 4.9.3 South Carlsbad 4-51 4.9.4 Encinitas 4-51 4.9.5 Torrey Pines 4-52 4.9.6 Buccaneer Beach (City of Oceanside)/South Carlsbad Alternative 4-52 5 CUMULATIVE IMPACTS 5-1 5.1 Cumulative Projects 5-1 5.2 Cumulative Environmental Effects 5-6 5.2.1 Geology and Soils 5-6 5.2.2 Coastal Wetlands 5-8 5.2.3 Water Resources 5-10 5.2.4 Biology 5-10 5.2.5 Land Use and Recreation 5-10 5.2.6 Safety and Environmental Health 5-11 5.2.7 Aesthetics 5-11 5.2.8 Structure and Utilities 5-11 5.2.9 Noise 5-11 211603000 vii TABLE OF CONTENTS (Continued) SECTION TITLE PAGE 6 IRREVERSIBLE OR IRRETRIEVABLE COMMITMENTS OF RESOURCES 6-1 8 9 10 THE RELATIONSHIP BETWEEN LOCAL SHORT-TERM USE OF THE HUMAN ENVIRONMENT AND THE MAINTENANCE AND ENHANCEMENT OF LONG-TERM PRODUCTIVITY LIST OF PREPARERS LIST OF AGENCIES AND PERSONS CONSULTED REFERENCES 7-1 8-1 9-1 10-1 LIST OF FIGURES NUMBER TITLE 1-1 Regional Location Map 1 -2 North Carlsbad Beach Fill Site 1 -3 South Carlsbad Beach Fill Site 1 -4 Encinitas Beach Fill Site 1-5 Torrey Pines Beach Fill Site 2-1 Typical Berm Cross-Sections, North and South Carlsbad 2-2 Typical Berm Cross-Sections, Encinitas and Torrey Pines 2-3 Buccaneer Beach Alternative Beach Fill Site 2-4 South Carlsbad Alternative Beach Fill Site 2-5 Typical Berm Cross-Sections, Buccaneer Beach and South Carlsbad Alternatives 2-6 Alternative Beach Replenishment Sites 2-7 Beach Replenishment Sites 3-1 North Carlsbad/Buccaneer Beach Biological Resources 3-2 South Carlsbad Biological Resources 3-3 Encinitas Biological Resources PAGE 1-7 1-9 1-11 1-13 1-15 2-4 2-6 2-11 2-13 2-15 2-16 2-19 3-17 3-23 3-25 VIU 211603000 TABLE OF CONTENTS (Continued) LIST OF FIGURES (Continued) NUMBER TITLE PAGE 3-5 Recreational Surfing Sites 3-33 3-6 North Carlsbad Receiver Site Existing Views 3-42 3-7 South Carlsbad Receiver Site Existing Views 3-43 3-8 Encinitas Receiver Site Existing Views 3-44 3-9 Northern Torrey Pines Receiver Site Existing Views 3-46 3-10 Southern Torrey Pines Receiver Site Existing Views 3-47 3-11 Buccaneer Beach Alternative Receiver Site Existing Views 3-48 3-12 Existing Structures and Utilities, North Carlsbad Site 3-50 3-13 Existing Structures and Utilities, South Carlsbad Site 3-52 3-14 Existing Structures and Utilities, Encinitas Site 3-53 3-15 Existing Structures and Utilities, Buccaneer Beach Alternative Site 3-55 4-1 Mean Sea Level Shoreline Response, North Carlsbad Site 4-3 4-2 Mean Sea Level Shoreline Response, South Carlsbad Site 4-6 4-3 Mean Sea Level Shoreline Response, Encinitas Site 4-8 4-4 Mean Sea Level Shoreline Response, Torrey Pines Site 4-10 4-5 Mean Sea Level Shoreline Response, Buccaneer Beach Alternative Site 4-13 4-6 Mean Sea Level Shoreline Response, South Carlsbad Alternative Site 4-14 5-1 Cumulative Projects 5-2 5-2 Cumulative Mean Sea Level Shoreline Response from South Oceanside to North Carlsbad 5-5 LIST OF TABLES NUMBER TITLE PAGE ES-1 Beach Fill Quantities ES-2 2-1 Phase II Beach Replenishment Characteristics 2-5 2-2 Alternative Beach Replenishment Characteristics 2-9 3-1 Longshore Sediment Transport Rate Estimates for the Oceanside Littoral Cell 3-3 211603000 IX TABLE OF CONTENTS (Continued) LIST OF TABLES (Continued) NUMBER TITLE PAGE 3-2 Ambient Acoustical Conditions at North Carlsbad 3-57 3-3 Ambient Acoustical Conditions at South Carlsbad 3-59 3-4 Ambient Acoustical Conditions at Encinitas 3-60 3-5 Ambient Acoustical Conditions at Torrey Pines 3-63 3-6 Ambient Acoustical Conditions at Buccaneer Beach 3-65 4-1 Expected Noise Impacts Due to Replenishment Activities 4-50 5-1 Comparison of Cumulative Impacts to Individual Beach Fills 5-7 5-2 Inlet Maintenance Responsibility 5-9 211603000 EXECUTIVE SUMMARY The proposed action involves the onshore placement of dredged material for beach replenishment at receiver sites located in North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines. Alternative beach replenishment sites include Buccaneer Beach in South Oceanside and an extension to the South Carlsbad site. A Phase I Environmental Assessment (EA) was previously prepared for beach replenishment at South Oceanside and Cardiff/Solana Beach, and a Finding of No Significant Impact was issued for that action. This Phase II EA addresses beach replenishment operations including transport of sediment via hopper dredge from dredging locations in San Diego Bay, placement of the dredge at various offshore locations, pumping of sediment onto the receiver beaches, and placement of sediment using grading equipment. The purpose and need of the proposed action is to replenish beaches with critical erosion problems, in accordance with a request submitted to the Navy by the San Diego Association of Governments' (SANDAG) Shoreline Erosion Committee. Implementation of the proposed action is intended to provide a wider recreational beach, reduce erosion, and protect the shoreline. Beach replenishment would provide an immediate benefit by maximizing onshore beach fill in the Oceanside Littoral Cell, rather than placing sediment in the nearshore zone. The proposed action includes beach replenishment at four receiver sites; however, an alternative plan was included after sensitive marine resources were identified in the nearshore zone at the Encinitas receiver site. Due to potential long-term impacts to sensitive marine resources, the majority of the Encinitas beach fill would be placed at Buccaneer Beach in South Oceanside, and additional fill would be placed at South Carlsbad. Proposed and alternative beach fill quantities are included in Table ES-1. Sand placement operations for the proposed action would occur at North Carlsbad from October to mid-November 1997; at South Carlsbad from mid-November 1997 to January 1998; at Encinitas from January to mid-April 1998; and at Torrey Pines from mid-April to June 1998. Should the alternative plan be implemented, sand placement would occur at Buccaneer Beach from mid-July to October 1997; at North Carlsbad from November 1997 to January 1998; at South Carlsbad from January to April 1998; and at Torrey Pines from April to June 1998. 211603000 ES-1 Table ES-1 BEACH FILL QUANTITIES Proposed Action Beach Fill Sites Fill Quantities (m3) North Carlsbad 420,510 South Carlsbad 420,510 Encinitas 871,620 North Torrey Pines 279,545 South Torrey Pines 2 1 7,425 TOTAL 2,209,610 Alternative Plan Beach Fill Sites Fill Quantities (m3) Buccaneer Beach 580,245 North Carlsbad 420,510 South Carlsbad 711,885 North Torrey Pines 279,545 South Torrey Pines 2 1 7,425 TOTAL 2,209,610 Beach replenishment operations (i.e., sand pumping and grading) would occur 24 hours per day, 7 days a week. Operations would occur at all of the identified receiver beaches at various times throughout the day and night. A summary of impacts for each environmental issue analyzed in this EA is presented below. GEOLOGY AND SOILS The proposed action would result in short-term changes to the existing beach profile. Beach fill would be spread by littoral processes and would affect beach areas north and south of the receiver sites, causing widening of beach areas other than the receiver sites. However, this effect would be short term, as sand transport modeling predicts that beach fill would be transported off beaches into the nearshore zone over a period of 2 years. Accumulation of sediment in the nearshore environment would potentially affect breaking waves less than 1 meter (m) (3.3 feet [ft]) hi height. However, this effect would be negligible and would not be considered significant. Beach fill would be transported through natural seasonal and littoral processes. Onshore beach fill is predicted to erode over a 1- to 2-year period, moving into the nearshore area. The maximum sediment movement is predicted to extend approximately 350 m (1,150 ft) offshore and 4,000 m (13,000 ft) upcoast and downcoast of the North Carlsbad site; 400 m (1,300 ft) offshore and 6,000 m (19,700ft) upcoast and downcoast of the South ES-2 211603000 Carlsbad site; 450 m (1,500 ft) offshore and 9,000 m (29,500 ft) upcoast and downcoast of the Encinitas site; 500 m (1,600 ft) offshore and 6,000 m (19,700ft) upcoast and downcoast of the Torrey Pines sites; and 350 m (1,150 ft) offshore and 5,000 m (16,400ft) upcoast and downcoast of the Buccaneer Beach alternative site. A minor increase in average sand thickness on the order of 0.1 to 0.3 m (4 inches [in] to 1 ft) would be anticipated to occur at all receiver sites. No significant impacts to coastal geology or littoral processes would occur upon implementation of the proposed action. COASTAL WETLANDS The proposed action would cause accumulation of sediments at lagoon inlets and river/creek outfalls in the vicinity of the receiver sites. Sediment transport modeling performed by Frederic R. Harris, Inc. (FRH), indicates no impacts would occur to lagoon inlets and river/creek ocean outfalls at San Luis Rey River, Loma Alta Creek, Agua Hedionda Lagoon, San Elijo Lagoon, or San Dieguito Lagoon. Sand transport modeling results indicate that approximately 19m (62 ft) of sediment accretion would occur at Buena Vista Lagoon as a result of beach replenishment at North Carlsbad; however, no adverse impacts would occur assuming the City of Carlsbad maintains the ocean outflow path. Similarly, approximately 43 m (140 ft) of sediment accretion would occur at Encinas Creek as a result of sand placement at South Carlsbad; however, no impacts are anticipated due to the surrounding high land at the discharge point (FRH 1997). Approximately 35m(115ft)of sand accretion is predicted at Batiquitos Lagoon from the Encinitas fill site, which would potentially lead to shoaling and/or closure of the lagoon. The California Department of Fish and Game currently dredges the lagoon mouth at Batiquitos to ensure tidal flow; assuming maintenance continues, no significant impacts would occur. Approximately 19 m (62 ft) of sediment accretion would occur at Los Penasquitos Lagoon within 12 months of beach replenishment, which would cause potential closure of the lagoon. The Los Penasquitos Lagoon Foundation currently performs maintenance dredging of the lagoon inlet; assuming maintenance dredging continues, no significant impacts would occur as a result of sediment accretion at the lagoon mouth. Therefore, no impacts to lagoon inlets and river/creek outfalls would occur from implementation of the proposed action assuming routine maintenance dredging continues at the identified locations. To ensure that significant impacts to lagoon inlets would not occur, a monitoring plan would be established. The monitoring plan would require approval from the Army Corps 211603000 ES-3 of Engineers (ACOE) (in consultation with appropriate resource agencies) to verify the results of the sediment transport analysis. Baseline profiles would be measured prior to sediment discharge and monitored through June 1, 2001. Areas that would be monitored include lagoon mouths, entrance channels, lagoon interiors, and adjacent areas. The Navy would provide mitigation for any increased rate of sand accumulation or lagoon mouth closures resulting from the proposed action above that which normally occurs, as determined by ACOE in consultation with the resource agencies. Mitigation measures would consist of opening closed lagoon inlets and/or removal of sediment accumulation at the lagoon mouths as a result of proposed fill activities. The Navy has obtained written assurance from SANDAG, as well as affected municipalities, that implementation of the identified monitoring, documentation, and mitigation would occur, including any other requirements related to potential effects on ocean inlets. These assurances have been formalized in a cooperative agreement (CA) between SANDAG and the Navy covering areas potentially affected by proposed beach replenishment operations. Potential effects are assessed in the Beach Sand Transport and Sedimentation Report prepared by FRH (1997). Coastal wetland areas subject to the CA include Agua Hedionda Lagoon, Batiquitos Lagoon, San Elijo Lagoon, San Dieguito Lagoon, and Los Penasquitos Lagoon. Although potential effects to each of these lagoons would differ, the Navy has included each area as a precautionary measure. WATER RESOURCES The proposed action would cause a temporary increase in turbidity, which could potentially affect water quality conditions in the nearshore environment. Increased turbidity caused by suspended particles in the water column would occur as a result of return water from pumping operations. Turbidity would potentially affect marine organisms and kelp/surfgrass beds in the nearshore area. However, the proposed action includes the use of longitudinal dikes to reduce turbidity during sand placement operations. Additionally, approximately 97 percent of the beach fill consists of larger grain size material (>63 um), which settles rapidly and would not significantly increase turbidity. Furthermore, intervals between pumping operations would allow suspended particles sufficient time to settle. Therefore, turbidity would be minimized in the nearshore environment and would not cause significant water quality impacts. ES-4 211603000 Regional Water Quality Control Board (RWQCB) conditions require that supernatant (water samples) from a loaded barge be collected three times per week and analyzed for polar and nonpolar oil and grease. Weekly monitoring of bacteria contamination 30 m (100 ft) down current of the discharge point is also required per the Waste Discharge Requirements. The RWQCB conditions would allow verification that significant water quality impacts would not occur. BIOLOGY The proposed action would bury intertidal organisms at all identified receiver beaches, resulting hi mortality. Subtidal organisms would be affected by erosion of beach fill, resulting in burial of nonmobile subtidal invertebrates. However, characteristic organisms of the intertidal and subtidal zones would be expected to recolonize at a rapid rate. As onshore sand placement would be short term; no significant impacts to intertidal and subtidal organisms would occur. Giant kelp beds offshore the receiver sites could be affected by barge operations associated with the proposed action. A sinker line running from the barge to the beach would be placed on the ocean floor to support the pump line. Kelp surveys at each of the receiver sites have been completed and sinker line placement is planned to avoid kelp bed habitat. Additionally, the kelp beds would be surveyed at least 30 days prior to proposed operations to ensure no adverse impacts. Sensitive marine resources in the nearshore area could be affected by transport of fill subsequent to placement. Sensitive marine resources include rocky intertidal reefs, subtidal vegetated reefs (including feather boa kelp, surfgrass, or sea fans), and nearshore reefs with giant kelp. Beach fill placement has been designed to avoid sensitive marine resources; however, direct burial of sensitive marine resources would be inevitable at the proposed Encinitas receiver site. Approximately 243,010 square meters (m2) (290,666 square yards [yd2]) of rocky intertidal habitat and vegetated subtidal reefs would be directly buried by onshore fill placement at the Encinitas site. This would result hi short- term and potential long-term impacts to sensitive marine resources at Encinitas. Due to direct burial and potential long-term impacts at Encinitas, this site was rejected for onshore beach replenishment. 211603000 ES-5 Beach fill placement at the proposed North Carlsbad, South Carlsbad, and Torrey Pines sites, and the alternative Buccaneer Beach and South Carlsbad sites, would avoid direct placement of fill on sensitive marine resources. Additionally, sediment transport modeling indicates that no significant impacts to these receiver sites would occur subsequent to sand placement. Although no significant impacts to sensitive marine resources are anticipated at these sites, the Navy would prepare and implement a monitoring plan to verify the results of the modeling. The program would include pre- discharge baseline studies and post-discharge monitoring. The monitoring program would be effective from the date of issuance of an ACOE permit through June 1, 2001 to confirm that sand discharge operations would not result in any significant long-term adverse impacts to sensitive marine resources. Mitigation would be the restoration of like habitat at a 1:1 ratio as a first priority. Consideration would be given to the construction of artificial reefs (approximately 1 acre) as mitigation to offset potential impacts if like habitat restoration efforts were not feasible as determined by ACOE, in consultation with the resource agencies. Should ACOE and/or the resource agencies require mitigation, total mitigation costs for Phase II would not exceed $400,000. Mitigation costs for Phase I would not exceed $700,000; therefore, total mitigation costs for Phase I and II beach replenishment would not exceed $1.1 million. California grunion may spawn on the proposed receiver beaches during sand placement operations. Beach replenishment activities could potentially bury then- eggs or change the beach profile, resulting hi mortality. If grunion were observed spawning during sand placement, disposal of sand would immediately cease in the area of spawning and a buffer zone would be established surrounding the area of spawning. The buffer zone would extend 20 m (65 ft) shoreward of the highest water mark at the spawning area, and run 30 m (100 ft) upcoast and 30 m (100 ft) downcoast from the spawning area. A sand dike, parallel to the shoreline above the 20 m (65 ft) buffer zone, would be constructed along the entire 60 m (200 ft) lateral extent of the buffer zone to ensure that the discharge water would not enter the spawning area. The spawning areas would be recorded and mapped, and a written report would be provided to the ACOE and resource agencies within 24 hours of the spawning event. The buffer zone would be in place for a minimum of 14 days (the period of time for eggs to hatch). This would mitigate impacts to the grunion and would allow sand replenishment activities to continue in areas not effected by spawning. ES-6 211603000 The proposed action is not anticipated to affect sensitive bird species in the vicinity of sand deposition operations. Sensitive species occurring in the vicinity of receiver areas include California least tern, western snowy plover, and California brown pelican. Each of these species forages in the vicinity of the receiver sites. The tern and pelican utilize offshore waters, while the plover typically uses intertidal habitat. Foraging areas would be reduced by proposed operations; however, as these species are mobile, they can move to adjacent unimpacted areas for foraging activities. No significant adverse impacts to sensitive species would occur. LAND USE AND RECREATION The proposed action would be consistent with all local, state, and federal land use plans. No impacts resulting from inconsistencies with applicable land use plans would occur. A Coastal Consistency Determination has been prepared and submitted to the California Coastal Commission to ensure the proposed action would be consistent with the California Coastal Act of 1976. Short-term impacts to recreation would occur at the receiver sites during sand replenishment operations. Recreational users would be dispersed to other local beaches until replenishment operations were complete. Implementation of the proposed action would not impact surf breaks dependent on subtidal reefs hi the vicinity of the North Carlsbad, South Carlsbad, Torrey Pines and Buccaneer Beach (alternative) receiver beaches. Potential impacts to beach surf breaks influenced by subtidal reefs could occur at the Encinitas receiver site. Beneficial impacts to beach surf breaks would occur from the formation of offshore sandbars at all receiver sites with identified sand or cobble beach surf breaks. SAFETY AND ENVIRONMENTAL HEALTH Short-term safety impacts would occur at the receiver sites during placement operations. The use of grading and construction equipment would create a hazardous condition that would cause potentially adverse impacts to public safety. However, the Navy would restrict public access to the receiver areas during replenishment operations. A 30 m (100ft) buffer zone would be maintained with fencing, barricades, and flagmen (as necessary). In addition, a 150 m by 150 m (approximately 500 ft by 500 ft) offshore 211603000 ES-7 buffer area would be maintained around the barge to ensure impacts from barge placement or pumping operations would not occur. Scarps, defined as cuts in the beach berm due to wave action, could form in the vicinity of the receiver beaches subsequent to sand placement. Scarps are a function of the existing beach berm height and wave height, and occur naturally along the shoreline. As beach berm heights would not be increased due to proposed fill operations, scarps larger than those forming under natural conditions would not occur. Therefore, significant safety hazards would not occur as a result of sand placement. AESTHETICS The proposed action would cause temporary adverse visual impacts during sand placement operations. Coastal views in the vicinity of the receiver areas would be impacted during operations due to the offshore barge and grading operations; however, these impacts would be short-term. In addition, the proposed action would have long- term beneficial effects to visual resources as a result of sand replenishment at receiver beaches and eradication of existing eroded beach profiles. Therefore, significant impacts to visual resources would not occur upon implementation of the proposed action. STRUCTURES AND UTILITIES Existing structures and utilities in the vicinity of the proposed receiver sites were surveyed for potential impacts due to sand placement. Public and private access stairs, sea walls, storm drains, and sewer outfalls were documented, and potential effects were assessed. The proposed action would not conflict with public service or access of these utilities or structures. Therefore, significant impacts would not occur. NOISE The proposed action would exceed the nighttime noise levels as identified in several of the local noise ordinances. The cities of Oceanside, Carlsbad, Encinitas, and Del Mar have noise ordinances that set allowable noise limits during daytime and nighttime hours. Grading operations associated with the proposed action would exceed the nighttime noise thresholds identified hi the local noise ordinances for the cities of Oceanside, Encinitas, and Del Mar. The North and South Carlsbad receiver sites are under the State of ES-8 211603000 California's jurisdiction. The proposed action was able to qualify for and has obtained variances to the city ordinances in Oceanside and Del Mar, which brings it into compliance with those local noise ordinances. Proposed operations were also found to be exempt from the noise ordinance in the City of Encinitas, and would meet State requirements at North and South Carlsbad. Therefore, the Navy is able to conclude that noise impacts would not be significant. 211603000 ES-9 This Page Intentionally Left Blank ES-10 211603000 SECTION 1 INTRODUCTION 1.1 BACKGROUND As a directive of the 1993 Base Realignment and Closure (BRAC) process, the Department of the Navy (Navy) will be relocating one NIMITZ class aircraft carrier berth (CVN homeport) from Naval Air Station Alameda, San Francisco Bay, California, to San Diego Bay. To accommodate the carrier, it is necessary for the Navy to dredge the carrier berthing area, turning basin, and the San Diego Bay navigation channel. Disposal of suitable dredged material is proposed at various receiver beach sites in San Diego County, California. As required under the National Environmental Policy Act (NEPA) (42 U.S.C. 4321- 4347), an Environmental Impact Statement (EIS) was prepared by the Navy that analyzed the environmental effects of the homeporting project, entitled Final Environmental Impact Statement for the Development of Facilities in San Diego/Coronado to Support the Homeporting of One NIMITZ Class Aircraft Carrier (Navy 1995a) This document is herein referred to as the Homeporting EIS. A Record of Decision (ROD) for the Homeporting EIS was issued by the Navy on December 15, 1995. Environmental impacts analyzed in the document included dredging operations, disposal of dredged material, construction of berthing and maintenance facilities, and mitigation for the loss of shallow bay habitat. In conjunction with the CVN homeporting project, the Navy is proposing beach replenishment at several receiver beaches along the coast of San Diego County in two phases. Phase I involves onshore sand placement in the intertidal and shallow subtidal zones at South Oceanside and Solana Beach. Phase II involves beach replenishment at North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines. Alternative beach receiver sites for Phase II include Buccaneer Beach in South Oceanside and an area north of Enemas Creek in South Carlsbad. As part of the Homeporting EIS, various beach areas were identified as suitable for disposal of dredged materials. These areas included sites within close proximity to the proposed receiver sites. Based on the location of these proposed receiver beaches and the proposed modifications to the Army Corps of Engineers (ACOE) 404/10 permit previously issued to the Navy for the disposal of dredged material, it was determined that a site-specific Environmental Assessment (EA) 211603000 1-1 be prepared through the use of tiering from the previously prepared EIS (as described in the Council on Environmental Quality [CEQ] Regulations, 40 Code of Federal Regulations [CFR] Part 1508.28). An EA was prepared for Phase I (Navy 1997a) and a Finding of No Significant Impact (FONSI) was issued for the action. This EA is intended to refine the analysis already presented to the public in the Homeporting EIS and provide detailed site-specific analyses required to modify the ACOE 404/10 permit for Phase II beach replenishment. Preparation of the EA is in compliance with CEQ Regulations of July 1, 1986 (40 CFR 1500-1508), Department of the Navy Procedures for Implementing the National Environmental Policy Act (32 CFR 775), and the guidelines contained in the Chief of Naval Operations Environmental and Natural Resources Program Manual (OPNAVINST 5090. IB) of November 1,1994. The following site-specific issues are addressed and analyzed in this EA: geology, coastal wetlands, water resources, biological resources, land use and recreation, safety and environmental health, aesthetics, utilities, and noise. The following is a summary of resource areas previously analyzed in the Homeporting EIS that do not require further analysis as part of the proposed action. Economics As discussed in the Homeporting EIS, beach replenishment using dredged sediments is generally considered a beneficial use of dredged materials. Beach erosion is a major problem along many beaches in southern California, Over half the shoreline along the San Diego coast has critical erosion problems that will cost the region's economy millions of dollars. San Diego Association of Governments (SANDAG) expects annual erosion-related costs to continually increase. Beach replenishment is one of the most cost-effective shoreline management alternatives for the region and is considered a beneficial impact for land use and development because it widens beaches, thus protecting property values and enhancing recreation facilities. Further analysis for this particular resource is not required for this EA. 1-2 211603000 Traffic Implementation of the proposed action would require delivery of construction equipment to the beach receiver sites. Construction vehicles would be driven to and kept on site for the duration of beach replenishment activities. Beach replenishment activities associated with the proposed action would not significantly affect transportation and circulation, as the proposed action would generate very few trips. Any increases in traffic volumes would be temporary; no long-term impacts to existing transportation and circulation patterns would occur. The proposed action does not present any new significant issues that were not already identified in the Homeporting EIS; therefore, further analysis is not required for this EA. Air Quality The majority of dust generated from beach replenishment activities would originate from grading of the disposed sand and would not exceed the significance threshold for emissions based on the Homeporting EIS. Emissions and dust generated by the proposed action would be temporary and short term and would comply with regulations set forth by the San Diego County Air Pollution Control District (APCD) Rules and Regulations. Equipment would be properly maintained to reduce emissions, and vehicle speed on the beach would be kept to a minimum to reduce the formation of dust clouds. Therefore, further analysis of this resource is not required as part of this EA. Cultural Resources The San Diego Museum of Man conducted an internal record search (April 23, 1997) for archaeological sites recorded within or in the vicinity of the proposed beach receiver sites. Six archaeological sites (W-ll, W-83, W-lll, W-3627, W-3629, and W-3630) were recorded in the vicinity of the proposed receiver sites; however, upon review of the archaeological survey reports, it was determined that sand placement would not affect any of the identified sites. Additionally, the proposed receiver areas are subject to repeated wave action that continually brings sediments onto the beach and causes heavy erosion; therefore, no significant impacts to cultural resources are anticipated as a result of the proposed action and further analysis of this resource is not required for this EA. 211603000 1-3 Environmental Justice To comply with Executive Order 12898 (Federal Actions to Address Environmental Justice [EJ] in Minority and Low-income Populations), ethnicity and poverty status in the vicinity of the proposed beach receiver areas have been compared to city, state, and national data to determine if any minority or low-income communities could potentially be disproportionately affected by the proposed action. Based on the location of the proposed action along the coastline where property values are typically high, the proposed beach receiver sites do not represent an area that would be considered a minority or low-income community. In addition, community resources would not be burdened and no adverse health conditions would be created. Therefore, further analysis of this resource is not required as part of this EA. 1.2 PURPOSE AND NEED The Navy proposes to dispose of suitable dredged material from San Diego Bay to beach receiver sites at North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines. Alternative receiver sites proposed for beach replenishment include Buccaneer Beach in South Oceanside and an area north of Enemas Creek in South Carlsbad. Onshore disposal at these locations is part of the Phase II EA for the beach replenishment plan associated with dredging operations in San Diego Bay for the homeporting of a NIMITZ class aircraft carrier, as previously described in the Homeporting EIS. Phase I, which included beach replenishment at South Oceanside and Solana Beach, was analyzed in a previous Environmental Assessment (Environmental Assessment for Beach Replenishment at South Oceanside and Cardiff/Solana Beach, California [Navy 1997a]). The purpose and need of proposed beach replenishment activities is to replenish beaches with critical erosion problems, in accordance with the request submitted to the Navy by SANDAG's Shoreline Erosion Committee on June 6, 1996. Beach replenishment would provide immediate benefit by maximizing onshore beach fill hi the Oceanside littoral cell, rather than placement of sand in the nearshore zone. Implementation of the proposed project would provide a wider recreational beach, reduce erosion, and protect the shoreline. 1-4 211603000 To successfully accomplish beach replenishment, the design needs to incorporate proper width, berm height, and slope specifications. Furthermore, the beach fill needs to be placed as far updrift (north) as possible within each jurisdiction to be sufficiently successful. Beaches in the Oceanside littoral cell have been steadily eroding. Because future shoreline erosion has the potential to increase both beach loss and property damage hi these areas, SANDAG has developed the Shoreline Preservation Strategy for the San Diego Region (1993), which identifies regional coastal areas with critical shoreline problems. SANDAG, the Navy, and local communities have provided input regarding specific sites for placement of sand and have identified beaches in Carlsbad, Encinitas, Torrey Pines, and alternative beach sites in Oceanside and Carlsbad for beach replenishment. Implementation of the proposed action would contribute to the replenishment of narrow beaches with sand to ensure that they are wide enough to provide increased property protection and recreational capacity, thereby meeting the objectives of the Shoreline Preservation Strategy. SANDAG's Shoreline Erosion Committee requested that the following volumes of sand be allocated nearshore and onshore to beach cities and state beaches: Site Million Cubic Yards Imperial Beach (nearshore) 1.70 Mission Beach (nearshore) .86 Torrey Pines (onshore) .65 Del Mar (nearshore) .45 Solana Beach (onshore) .57 Encinitas (onshore) 1.14 South Carlsbad (onshore) .55 North Carlsbad (onshore) .55 South Oceanside (onshore) .53 Under an existing ACOE Section 404/10 Permit, all nearshore sites have been permitted, as well as onshore sites at South Oceanside and Solana Beach under Phase I. The permit 211603000 1-5 is being modified to allow for onshore replenishment at the remaining sites under Phase II. The purpose of the Phase II beach replenishment plan is to provide onshore beach replenishment at North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines. Phase I (presented in separate environmental documentation) involved onshore sand placement at South Oceanside and Cardiff/Solana Beach for the same purpose. 13 LOCATION OF THE PROPOSED ACTION Implementation of the proposed action would occur on beaches in North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines hi San Diego County, California (Figure 1-1). The North Carlsbad receiver beach is located south of Buena Vista Lagoon between the lagoon inlet and Oak Avenue, which comprises the majority of public beach area under the City of Carlsbad's jurisdiction (Figure 1-2). A segment of approximately 1.2 kilometers (km) (0.7 miles [mi]) along the beach is proposed for replenishment. This beach segment consists of a predominantly flat sandy beach, extending from the surf line to rip-rap slopes and sea walls that protect existing beach-front residences. The South Carlsbad receiver beach is located south of Enemas Creek, between the creek outlet and the Batiquitos Lagoon inlet (Figure 1-3). This beach segment comprises the majority of South Carlsbad State Beach and covers approximately 2.2 km (1.4 mi). The existing beach in this area consists of a flat, sandy beach with scattered cobbles. The proposed receiver beach lies at the base of a steep slope varying in height from 18 to 24 meters (m) (60 to 80 feet [ft]). A parking area and the South Carlsbad State Beach Campground are located on the bluff above the receiver beach. The Encinitas receiver beach is located south of Batiquitos Lagoon between the lagoon inlet and Moonlight State Beach (Figure 1-4). This segment extends approximately 4.4km (2.7 mi) from the bluff directly south of Batiquitos Lagoon to Encinitas Boulevard, and comprises Leucadia State Beach, Encinitas Beach County Park, Seaside Gardens Park, and a portion of Moonlight State Beach. Steep cliffs abut the proposed receiver beach, which consists of a gently sloping sand beach with scattered rocks and cobbles. Several existing residences are located on the bluff above the receiver beach. 1-6 211603000 BUCCANEER BEAC ALTERNATIVE NORTH CARLSBAD ESCONDIDO s^78SOUTH CARLSBAD ENCINtTAS San Vicente POWAY \ Reservoir TORREY PINES DIEGO CHULA VISTA * BEACH REPLENISHMENT SITES FIGURE Regional Location Map 1-1 RENVIR ASS'MT(ENV)\Emriron AssesstnentVReceiver Beach EA\SD County Map The Encinitas site has been rejected due to direct burial of sensitive marine resources and potential long-term impacts. The alternative sites proposed for placement of the Encinitas beach fill material includes Buccaneer Beach in South Oceanside and additional fill at South Carlsbad. The Buccaneer Beach site extends from Loma Alta Creek to Buena Vista Lagoon. This beach segment consists of a gently sloping sand beach abutting rip-rap sea walls. The sea walls support existing beach-front residences, which span this alternative site. The South Carlsbad alternative site extends from Palomar Airport Road to Encinas Creek. A description of the South Carlsbad receiver beach and surrounding area is provided above. Refer to Section 2 of this EA for alternative selection criteria and maps of the alternative sites. The Torrey Pines receiver beach consists of two areas, one northern site and one southern site within Torrey Pines State Beach. The northern site is located along the northern portion of Torrey Pines State Beach, extending from 4th Street south approximately 0.9 km (0.5 mi). The southern site extends from the State Beach parking area south approximately 0.7 km (0.4 mi) (Figure 1-5). The existing beach at the northern site consists of a flat, sandy beach adjacent to steep cliffs. Railroad tracks and private residences are located on the bluff, approximately 15 to 25 m (50 to 80 ft) above the beach. The southern receiver site consists of a gently sloping sand and cobble beach adjacent to cliffs ranging hi elevation from 15 to 60 m (approximately 50 to 200 ft). The area on the bluff, above the southern receiver beach, is included within Torrey Pines State Reserve. 1.4 RELEVANT FEDERAL, STATE, AND LOCAL STATUTES, REGULATIONS, AND GUIDELINES National Environmental Policy Act of 1969 (NEPA) NEPA requires that federal agencies consider potential environmental consequences of proposed actions in their decision-making process. NEPA's intent is to protect, restore, or enhance the environment through well-informed federal decisions. CEQ was established under NEPA for the purpose of implementing and overseeing federal policies as they relate to this process. In 1978, CEQ issued Regulations for Implementing the Procedural Provisions of the National Environmental Policy Act (40 CFR §1500-1508 1-8 211603000 Legend North Carlsbad Beach Fill Site 1-2 OJ/IWJ Hlrtorlcal MaximumMpBadCai197*101998 Kelp Bad Canopy3M8/1997 Lagoon* OlfthoreRattrlcladZona Onthora R**trict«d Zone HnkwLlna BathymtlfY (1« "<« IUwvaJ) Railroad F I G U R E South Carlsbad Beach Fill Site 05/15W7 I I I HlMtrical Maximum M ID 19S8 Lagoon* ORihor* RtttrlrtMl Zon* Onihora R**trtct«d Zone Sinter Line Bathymtfrt (1/t aiettr latwval) Railroad m ',...' F I G U R E Enclnltas Beach Fill Site Hlttorlcal MaximumKilp Bad Cinoplat197% Io1998 Kelp Bad Canopy/18/13/18/1997 Lagooni Olfihore Restricted Zone Onihore Reatrlcted Zone A/ sinkarLlna /V Bathymelrvd/Znalerlalwval) /V Railroad Los Penasqui Lagoon Torrey FineaState Reserve F I G U R E Torrey Pines Beach Fill Sites 05/15)97 [CEQ 1978]), which were revised in 1986. These regulations specify that an EA be prepared to: • briefly provide sufficient analysis and evidence for determining whether to prepare an EIS or a FONSI; • aid in an agency's compliance with NEPA when an EIS is deemed unnecessary; and • facilitate EIS preparation when one is necessary. Clean Water Act (CWA) Section 31U33 USC 1321] Section 311 of the CWA prohibits and regulates liability for the discharge of oil or hazardous substances into or upon waters of the U.S. or adjoining shorelines which may present an imminent and substantial danger to natural resources or the public health or welfare, including, but not limited to fish, shellfish, wildlife, shorelines, and beaches. In compliance with Section 311 of the CWA, a Spill Prevention Control and Counter- Measure Plan (SPCC) would be developed and implemented prior to initiation of the proposed action. The preparation of an SPCC would ensure no significant impacts due to spillage of any petroleum products or hazardous substances during proposed operations both onshore and offshore the receiver beaches. Clean Water Act Section 404fbVl') Guidelines Section 404 of the CWA establishes a program to regulate the discharge of dredge and fill material into waters of the U.S., including dredged material placed in the ocean for beach replenishment or other beneficial uses. The proposed action complies with the guidelines promulgated by the Administrator, Environmental Protection Agency (EPA), under the authority of Section 404(b)(l) of the CWA (33 U.S.C. 1344). The primary purpose of fill activities is for beach replenishment. The 404(b)(l) evaluation was prepared for nearshore disposal as part of the homeporting project and a 404/10 permit was acquired by the Navy. The 404/10 permit sets conditions on a proposed action in order to reduce potential environmental impacts realized as part of the 404(b)(l) evaluation. The Navy has applied for a modification to the 404/10 permit in order to implement the proposed action. The 211603000 1-17 modified permit is required prior to the start of onshore sand placement operations because the permit as originally issued only addressed nearshore disposal of dredged material. Rivers and Harbors Act Section 10 of the Rivers and Harbors Act authorizes the ACOE to regulate all activities that affect the course, capacity, or coordination of waters of the U.S. Coastal Zone Management Act of 1972 and California Coastal Act of 1976 The Coastal Zone Management Act of 1972 requires management programs for coastal zones and is implemented through the California Coastal Act of 1976. Onshore disposal of dredged material requires concurrence from the California Coastal Commission due to possible effects to resources in the coastal zone. A Negative Determination (ND) has been prepared by the Navy for Phase II beach replenishment (ND-62-97). The California Coastal Commission concurs with the ND, which states that the proposed action is consistent with all applicable policies of the California Coastal Act of 1976. National Oceanic and Atmospheric Administration (NOAA) Federal Consistency Regulations NOAA Federal Consistency Regulations (15 CFR 930) require that federal actions be consistent with the Coastal Zone Management Act of 1972. As described above, compliance with the Coastal Zone Management Act has been satisfied through the preparation of a ND for the California Coastal Commission. Executive Order 11990 This order requires that governmental agencies, in carrying out then- responsibilities, provide leadership and "take action to minimize the destruction, loss, or degradation of wetlands, and to preserve and enhance the natural and beneficial values of wetlands." Implementation of the proposed beach replenishment plan would not be anticipated to adversely affect wetland areas near the proposed receiver sites. A monitoring program would be implemented as part of the project to ensure adverse impacts to wetlands do not occur. 1-18 211603000 Endangered Species Act of 1973 (ESA) The ESA protects threatened and endangered species by prohibiting federal actions that would jeopardize the continued existence of such species, or minimizing actions that would result in the destruction or adverse modification of any critical habitat of such species. Current endangered species information was requested from the U.S. Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service (NMFS) in compliance with Section 7 of the ESA. USFWS responded with concerns regarding threatened and endangered species that may occur in the vicinity of the proposed action. Specific concerns addressed the potential effects of the proposed action on foraging and breeding areas for the federally listed California least tem (Sterna antillarum browni), California brown pelican (Pelacanus occidentalis), and western snowy plover (Charadrinus alexandrinus). USFWS has reviewed the Public Notice for modifications to the ACOE 404/10 permit and the EA prepared for Phase I of the beach replenishment plan, and concurs with Phase I. Identical mitigation measures as referenced in Phase I would be implemented for Phase II, and there would be no direct burial of sensitive marine resources. Therefore, USFWS concurs with the proposed action. Fish and Wildlife Coordination Act The Fish and Wildlife Coordination Act requires that any federal agency proposing to control or modify any body of water must first consult with USFWS or the NMFS. The proposed action has been coordinated with USFWS, NMFS, and the California Department of Fish and Game (CDFG). USFWS concurs with the proposed action as described above. NMFS reviewed the EA for Phase I, and concurs with Phase I. Identical mitigation measures as referenced in Phase I would be implemented for Phase II, and there would be no direct burial of sensitive marine resources. Therefore, NMFS concurs with the proposed action. Migratory Bird Treaty Act of 1972 This Act prohibits the taking or harming of any migratory bird, its eggs, nests, or young without an appropriate permit. 211603000 1-19 Local Jurisdictional Noise Regulations State of California Noise Regulations (State Beach Areas) The South Carlsbad and the Torrey Pines sites are under the jurisdiction of the State of California Department of Parks and Recreation. Although no formal noise standards exist for activities within state beaches, the California Department of Health Services (formerly known as the Office of Noise Control), has identified standards for noise levels based upon land use compatibility. These standards, known formally as the State of California Model Noise Ordinance, would serve as applicable guidelines for noise impact determination at state-operated campgrounds (Dupree 1997). City of Del Mar Construction Noise Regulations Construction noise within the City of Del Mar is governed by City of Del Mar Municipal Code, Chapter 9.20.040, and deals with specific prohibited noises. City of Carlsbad Construction Noise Regulations Construction noise within the City of Carlsbad is governed by Municipal Code Section 8.48.010 and deals with specific prohibited noises. City ofEncinitas Construction Noise Regulations Construction noise within the City of Encinitas is governed by Performance Code Section 30.40.010. This section sets forth a list of performance standards dealing with any noise emissions affecting adjacent property. The City ofEncinitas has determined that Phase II beach replenishment activities are exempt from the noise abatement ordinance per Municipal Code Section 9.32.417(c), "Federal or state preempted activities." City ofOceanside Construction Noise Regulations Construction noise within the City of Oceanside is governed by the Oceanside City Code Section 38.17 and deals with specific prohibited noises. Subsection H of the City Code deals with construction equipment of a pneumatic or diesel nature. 1-20 211603000 1.5 INTERAGENCY COORDINATION The lead agency for the proposed action is the U.S. Department of the Navy in cooperation with SANDAG. An agency scoping meeting for the Phase I Environmental Assessment for Beach Replenishment was held on February 21, 1997 with the following agencies hi attendance: Army Corps of Engineers U.S. Fish and Wildlife Service National Marine Fisheries Service California Coastal Commission San Diego Association of Governments U.S. Navy, Southwest Division Coordination with each of these agencies has continued throughout preparation of the Phase IIEA. Other agencies consulted as part of this EA process included: Environmental Protection Agency California Department of Fish and Game California Department of Parks and Recreation California Regional Water Quality Control Board (San Diego, Region 9) City of Carlsbad City of Del Mar City ofEncinitas City ofOceanside City of San Diego 211603000 1-21 This Page Intentionally Left Blank 1-22 211603000 SECTION 2 DESCRIPTION OF THE PROPOSED ACTION AND ALTERNATIVES 2.1 ALTERNATIVE SELECTION CRITERIA An overall discussion of project alternatives was presented in the Homeporting EIS. Specific sites proposed for beach replenishment were established based on the following selection criteria. SANDAG Shoreline Preservation Strategy SANDAG has developed the Shoreline Preservation Strategy for the San Diego Region (1993), which identifies regional coastal areas with critical shoreline problems. Based on this study and input from local communities, beaches in critical need of replenishment were identified. The SANDAG study was used to determine site-specific alternatives for beach replenishment. Implementation of the proposed action reflects the critical need for sand at North and South Carlsbad, Encinitas, and Torrey Pines. Marine Resources Beach sites along the San Diego coast were analyzed for onshore beach replenishment suitability. Beach replenishment was not considered an alternative for onshore disposal in areas with significant sensitive marine resources, such as rocky intertidal reefs, subtidal vegetated reefs (that hold feather boa kelp, surfgrass, or sea palm), and/or nearshore reefs with giant kelp. Reefs that support sea fans are also considered sensitive because sea fans are indicative of persistent reefs that are not covered by sand. Beach Replenishment Design Four beach fill construction design alternatives were evaluated to achieve the most environmentally superior design that maximizes beneficial use of dredge material for recreational beach enhancement and minimizes potential adverse impacts (Frederic R. Harris, Inc. [FRH] 1997). 211603000 2-1 The four alternative beach fills considered were: • Low Berm (lower than minimum) (+1.0 m elevation, 35:1 slope) In comparison to the other alternatives, the low berm alternative would provide reduced beneficial impacts for recreation and shore protection as the berm is expected to erode at a higher rate over the short term (3 to 6 months). In addition, this alternative would be very difficult and very costly, if not impractical to construct. Therefore, this alternative was not considered further. • Minimum Berm (+1.7 m elevation, 20:1 slope) The minimum berm alternative is expected to erode somewhat slower than the low berm alternative over the short term and meets the purpose of the proposed action. Under this design, scarps would form on beaches at a point where waves break on the beach; however, this alternative is not expected to lead to a scarp over 1 m (3.3 ft) high. • Maximum Berm (+2.8 to 3.4 m elevation, 10:1 slope) The maximum berm alternative is expected to erode somewhat slower than the minimum berm alternative over the short term and meets the purpose of the proposed action. Under this alternative, the berm elevation would match the natural beach berm elevation that is particular to each site location and may be different between sites. This alternative is not expected to lead to a scarp significantly over 2 m (6.6 ft) high. • Block Berm (higher than maximum) (+4.2 m elevation, 3:1 slope) The block berm alternative is expected to erode somewhat slower than the maximum berm alternative over the short term and would be similar to the berm constructed for the Batiquitos Lagoon disposal at South Carlsbad. This profile would be built with an extremely high berm elevation and steep beach slope, which would likely result in a substantial scarp height in excess of 2.5 m (8.2 ft). Due to potential safety impacts associated with extreme scarps, this alternative was not considered further. The minimum amount of fill that can be placed on the beach hydraulically is controlled by the pumping rate of the dredge. For beach replenishment operations to be cost effective, enough quantity per unit length has to be placed onshore to allow the dredge 2-2 211603000 pump to operate efficiently. This fill quantity is estimated to be in the range of 125 to 150 cubic meters per meter (mVm). The proposed beach replenishment fills have unit quantities at or above these levels. 2.2 PROPOSED ACTION - BEACH REPLENISHMENT The proposed action involves the replenishment of sand on receiver beach sites in North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines as previously shown in Figures 1-2 through 1-5. Beach replenishment would be performed using suitable sediment dredged from San Diego Bay for the homeporting of a NIMITZ class aircraft carrier at Naval Air Station North Island (NASNI) in San Diego. Receiver beaches were chosen based on the presence/absence of sensitive marine resources and compatibility with chemical and grain size sediment analyses that were performed on the dredged sediment. Dredging of the San Diego Bay channel is anticipated to yield approximately 5.4 million cubic meters (m3) (7 million cubic yards [cy]) of material. The proposed action would utilize approximately 2,209,610 m3 (2,850,400 cy) of dredged sediment for use as beach replenishment at the four identified sites. The remaining beach fill would be disposed of at permitted onshore sites hi South Carlsbad and Solana Beach (as part of Phase I beach replenishment), or at permitted nearshore sites in Oceanside, Del Mar, Mission Beach, and Imperial Beach. Proposed quantities for Phase II beach replenishment at the receiver sites, including proposed berm widths, heights and slopes, are included in Table 2-1. Beach replenishment at North Carlsbad would involve onshore placement of sand from a point directly south of the Buena Vista Lagoon inlet to a point directly north of Oak Avenue, as shown in Figure 1-2. Dredged sediment would be placed on the existing sand beach and graded to form a berm. The top of the berm would be constructed to an elevation of approximately +2.9 m (+9.5 ft) Mean Sea Level (MSL) and would be flat, with a width of approximately 60 m (195 ft). From this point, the berm would slope at a 10:1 ratio (horizontal distance:vertical distance) approximately 60 to 80 m (195 to 260 ft) into the intertidal zone to an average depth of -2 m (-6.6 ft) MSL. The berm would extend upcoast and downcoast approximately 1.2km (0.7 mi). A representative cross section of the proposed berm is shown in Figure 2-1. Berm construction may be adjusted during fill placement, depending on actual field conditions. The beach elevation would not be constructed higher than the natural berm elevation for each beach site. 211603000 2-3 ELEVATION MSL (M) ELEVATION MSL (M)10 O N> .f* N> O ro .bTOB M^\\\ \\\\\\ BERMWlDTH 60M l \ \\\\ X""s +2.9 M .^ MSL \. \/XX SLOPE RA 10 10:1 s^>^ -40 0 40 80 12 DISTANCE (M) FROM TOP OF BERM (TOB) NORTH CARLSBAD TYPICAL CROSS SECTION TOB .BERM WIDTH' VARIESL i i\ 40MTOe N•*.. OM --_- / MSL r- • • ^**^ ^X \^^v ' x ..^ /^^N SLOPE RA 10 20:1 "" — — ^ 4 2 0 -2 0 4 2 0 -2 -40 0 40 80 120 DISTANCE (M) FROM TOP OF BERM (TOB) 0 40 SOUTH CARLSBAD TYPICAL CROSS SECTION D-D.- VERTICAL 1:100 ^j^pffifoi ^%5§SS$^ Typical Berm Cross Sections, North and South Carlsbad FIGURE 2-1 E\ENVIR A8S'MT(ENV)\ENVIRON ASSESSMENTVRecelver Beach EA\Cross-sectlons Table 2-1 PHASE II BEACH REPLENISHMENT CHARACTERISTICS Beach Fill Site North Carlsbad South Carlsbad Encinitas Torrey Pines North Torrey Pines South Quantity Dredge Cut (m3) 420,510 420,510 871,620 279,545 217,425 Width (m) 60 40-50 40-50 70 70 Berm Height (m, MSL) 2.9 1.7 1.7 2.6 2.6 Slope 10:1 20:1 20:1 10:1 10:1 TOTAL 2,209,610 Beach replenishment at the South Carlsbad site would consist of the placement of dredged sediment from a point directly south of Encinas Creek to a point south of Poinsettia Lane, as shown in Figure 1-3. A berm would be constructed to an elevation of approximately +1.7 m (+5.6 ft) MSL. The berm would be flat with a width of approximately 40 to 50 m (130 to 160 ft), then slope at a 20:1 ratio for approximately 60 to 80 m (195 to 260 ft) to a depth of -2 m (-6.6 ft) MSL. The berm would extend up- and downcoast approximately 2.2km (1.4 mi). A representative cross section of the proposed berm is shown in Figure 2-1. Beach replenishment at Encinitas would involve the placement of dredged sediment from a point directly south of the Batiquitos Lagoon inlet to the northern end of Moonlight State Beach, as shown in Figure 1-4. A berm would be constructed to an elevation of approximately +1.7 m (+5.6 ft) MSL. The berm would be flat with a width of approximately 40 to 50 m (130 to 160 ft), then slope at a 20:1 ratio for approximately 60 to 80 m (195 to 260 ft) to a depth of -2 m (-6.6 ft) MSL. The berm would extend up- and downcoast approximately 4.4 km (2.7 mi) along the beach. A representative cross section of the proposed berm is shown in Figure 2-2. The Encinitas site has been rejected due to direct burial of sensitive marine resources and potential long-term impacts. 211603000 2-5 ELEVATION MSL (M) ELEVATION MSL (M)IV) O IO «. K> O S> £kTOB \ .v \ \ \ \ &ERM WIDtH VARIES ' 40M TC I V\s \ s »60M " /~MS */ ^^^^^ - ^ ^ ^ X. ^X /kx v SLOPE RA id 20:1 \ ^ •s> •40 0 40 80 12 DISTANCE (M) FROM TOP OF BERM (TOB) ENCINITAS TYPICAL CROSS SECTION TOB N L -4-\ \ 11 1 \ BERM Wl6lH TOM \s«._. + 2.6 M X^TSIL ^X. \V \ '"^^x /x^ ^s SLOPE RATIO 10:1 X ""•"-- 4 2 0 -2 0 4 2 0 -2 -40 0 40 80 120 DISTANCE (M) FROM TOP OF BERM (TOB)0 40 TORREY PINES NORTH/SOUTH TYPICAL CROSS SECTION f^n^f^^^HORIZONTAL 1:1000VERTICAL 1:100 s$$S$>%\ ftwJff JTI I Typical Berm Cross Sections, Enclnltas and North/South Torrey Pin FIGURE 2-2 EVENVIR ASS'MT(ENV)\ENVIRON ASSESSMENT\Receiver Beach EA\Cross-aactlons Although the Encinitas site has been rejected, a full analysis of impacts associated with beach fill at this site has been included in this EA. Beach replenishment at the Torrey Pines site would consist of the placement of dredged sediment at two locations, one northern and one southern. The northern receiver site would extend approximately 0.9 km (0.5 mi) south of 4th Street, and the southern site would extend approximately 0.7 km (0.4 mi) south of the Torrey Pines State Beach parking area, as shown in Figure 1-5. Berms would be constructed at these locations to an elevation of approximately +2.6 m (+8.5 ft) MSL. The berm would be flat with a width of approximately 70 m (230 ft), then slope at a 10:1 ratio for approximately 60 to 80 m (195 to 260 ft) to a depth of-2 m (-6.6 ft) MSL. A representative cross section of these berms is shown in Figure 2-2. Beach replenishment operations would include the use of a trailing suction hopper dredge, which would load sediment from various dredging locations in San Diego Bay and move north to the receiver beaches for sand placement. The hopper dredge would anchor approximately 500 to 1,300 m (1,640 to 4,300 ft) offshore of the receiver beach and would connect via a 1-m in diameter (dia) (36 inches [in] in dia) rubber floating pump line attached to a floating platform called a "mono buoy," which is used to interconnect the floating pump line with a steel sinker pipeline that would run the rest of the distance to the beach. The steel sinker pipeline would be placed to avoid sensitive marine resources. The mono buoy, which is less than 9 m (30 ft) in diameter and does not hold any mechanical equipment, would be anchored a minimum of 500 m (1,640 ft) offshore at a water depth of approximately -12m (-40 ft) MSL using four navigational buoys. The mono buoy would remain anchored in the same area off each receiver beach throughout pumping operations. The hopper dredge would hook up to the mono buoy and proceed to hydraulically pump a mixture of sand and sea water through the rubber pump line onto the beach. The sand would then be graded and placed using two Caterpillar D8 bulldozers. A 966 Caterpillar forklift would be used to move the pump line. Approximately five to seven construction personnel would be necessary to operate the pump line and grading equipment on the beach. The beach replenishment process would involve the construction of longitudinal dikes along the waterline to trap the maximum amount of sand above the surf zone. Sand would be placed using a single discharge point behind the dikes. Dikes placed along the 211603000 2-7 shoreline would retain return water from the pumping operation, thus decreasing turbidity and allowing suspended particles to settle out. The hopper dredge can carry a maximum capacity of 8,520 m3 (approximately 11,000 cy) of sand per load. It is anticipated to take approximately 2 to 3 hours to hook up the pump line, pump a full load onto the receiver beach, and disconnect the line. The dredge would move south for reloading approximately two to three times per day. Travel time for reloading would depend on the distance of the receiver beach from the loading location in San Diego Bay. The dredge moves at approximately 12 km per hour (7.5 mi per hour) at maximum speed. Beach replenishment operations are scheduled to run 24 hours a day, 7 days a week. Operations would occur at various times throughout the day and night. Sand placement operations for the initial proposed action were scheduled to occur at North Carlsbad from October to mid-November 1997; at south Carlsbad from mid- November 1997 to January 1998; at Encinitas from January to mid-April 1998; and at Torrey Pines from mid-April to June 1998. Alternative plan sand placement would occur at Buccaneer Beach from mid-July to October 1997; at North Carlsbad from November 1997 to January 1998; at South Carlsbad from January to April 1998; and at Torrey Pines from April to June 1998. During periods of high seas, the hopper dredge would be moved into harbor and anchored until better weather permitted operations to resume. Due to construction activities associated with beach replenishment operations (e.g., pumping sand onto the beach, grading, bulldozer equipment, etc.), the identified receiver beach areas would be temporarily closed to public access. Closure would be maintained on a 24-hour basis during the scheduled project operation time. A 30 m (100 ft) buffer zone would be maintained between the operational area and open public beaches. The Navy would provide and maintain safety measures in the vicinity of the receiver beaches including fencing, barricades, flagmen, and warning signals as necessary. In addition to onshore restricted access, an offshore area would be closed to the public to allow proper anchoring of the dredge and pumping operations. An offshore area of approximately 150 m by 150 m (about 500 ft by 500 ft) would be restricted around the hopper dredge while it is anchored off of the receiver beaches. Restricted access is recommended solely for the purpose of public safety. 2-8 2J1603000 2.3 ALTERNATIVES CONSIDERED 2.3.1 Buccaneer Beach/South Carlsbad Alternative After field investigations of the proposed receiver beaches, it was determined that, due to potentially significant impacts to sensitive marine resources at the Encinitas receiver beach, an alternative plan for onshore placement would be necessary. Due to direct burial of sensitive marine resources and potential long-term impacts at the Encinitas site, the beach fill intended for Encinitas would be redistributed to Buccaneer Beach in South Oceanside and the South Carlsbad receiver beach. The alternative plan would place sand at Buccaneer Beach from a point directly south of the Loma Alta Creek outfall to a point directly north of the Buena Vista Lagoon inlet, as shown in Figure 2-3. The alternative fill would extend 1.4 km (0.9 mi) along the beach. Additionally, sand would be placed north of Encinas Creek at the South Carlsbad receiver beach, elongating the proposed fill area at South Carlsbad by approximately 600 m (2,000 ft), as shown in Figure 2-4. Table 2-2 represents quantities for beach replenishment if the alternative beach replenishment plan is implemented. Table 2-2 ALTERNATIVE BEACH REPLENISHMENT CHARACTERISTICS Beach Fill Site Buccaneer Beach North Carlsbad South Carlsbad Torrey Pines North Torrey Pines South Quantity Dredge Cut (m3) 580,245 420,510 711,885 279,545 217,425 Width (m) 60 60 50 70 70 Berm Height (m, MSL) 2.9 2.9 2.9 2.6 2.6 Slope 10:1 10:1 10:1 10:1 10:1 TOTAL 2,209,610 211603000 2-9 The alternative plan would place sand at Buccaneer Beach to an elevation of approximately +2.9 m (+9.5 ft) MSL. The berm would be flat with a width of approximately 60 m (195 ft), then slope at a 10:1 ratio for approximately 80 m (260 ft) into the intertidal zone to a depth of-2 m (-6.6 ft) MSL. A representative cross section of the berm is shown in Figure 2-5. With the addition of fill at the South Carlsbad receiver site, the beach fill (berm) design would change from that of the proposed action. The berm would be constructed to an elevation of approximately +2.9 m (+9.5 ft) MSL and would be flat with a width of approximately 50 m (160 ft). From this point, the berm would slope at a 10:1 ratio for approximately 80 m (260 ft) into the intertidal zone to a depth of -2 m (-6.6 ft). A representative cross section of this berm design is shown in Figure 2-5. 2.3.2 North Oceanside (Oceanside Harbor to Oceanside Pier) Alternative The North Oceanside Alternative consists of the beach area from Oceanside Harbor to Oceanside Pier (Figure 2-6). This alternative includes Harbor Beach (in the vicinity of Oceanside Harbor), the San Luis Rey River mouth, and a section of Oceanside City Beach from the San Luis Rey River mouth to Oceanside Pier. Harbor Beach affords a wide, relatively sheltered beach while the City Beach (north of the pier) is wide due to sand bypassing from the Oceanside Harbor jetty (Sterrett and Flick 1994). The beach narrows considerably south of the pier until it disappears at Wisconsin Avenue. The beach area north of Oceanside Pier has been historically replenished as a result of dredging associated with the maintenance of Oceanside Harbor (ACOE 1994). A SANDAG study determined that, due to wave protection afforded by the Oceanside Harbor jetty and previous beach replenishment along this segment, the beach north of the pier is not currently in critical need of sand replenishment. Therefore, this beach segment was rejected as an alternative for the proposed action. 23.3 Agua Hedionda Alternative The Agua Hedionda Alternative includes the beach area in the vicinity of the Agua Hedionda Lagoon inlet/outlet (Figure 2-6). Specifically, this alternative area extends from Oak Street at the southern limits of the North Carlsbad receiver site to Palomar Airport Road at the northern limits of the South Carlsbad receiver site and includes the majority of Carlsbad State Beach. Currently, San Diego Gas and Electric (SDG&E) uses 2-10 211603000 HIKorical MaximumK«lpBedCanoplw197% Io1998 Lagooni Onthora RMtricttd Zone BUhymrtiY (1/2 m<t«r litwvii) F I G U R E Buccaneer Beach Alternative Beach Fill Site Legend Hlttorioal MaximumKalp Bed Canoplw19ft lo 1996 Lagoont Onihor«HMlrlctedZone '"••/ Bathymetry (1/Z auter latwval) /V Railroad \ \ N- " //•'•• '~\\v\\\\U\\\u \ \ -. \ ; South Carlsbad Alternative Beach Fill Site TOB UJ .2 £BERM WIDTH 60M SLOPE RATIO 10:1 -2 •40 0 40 80 DISTANCE (M) FROM TOP OF BERM (TOB) SOUTH CARLSBAD (ALTERNATIVE) TYPICAL CROSS SECTION 120 TOB UJ -2 BERM WIDTH 60M + 2.9M SLOPE RATIO 10:1 -40 0 40 80 120 DISTANCE (M) FROM TOP OF BERM (TOB) BUCCANEER BEACH (ALTERNATIVE) TYPICAL CROSS SECTION VERTICAL 1:100 Typical Berm Cross Sections, Buccaneer Beach/South Carlsbad Alternative FIGURE •* ^^P North Carlsbad Alternative Agua Hedionda Alternative South Encinitas Alternative 7000 FEET San Elijo State Beach Alternative Del Mar Alternative Torrey Pines Design Alternative Black's Beach Alternative Scripps Alternative F I G U R E Alternative Beach Replenishment Sites 2-6 Agua Hedionda Lagoon as a source of cooling water for the Encina Power Plant, located adjacent to the lagoon. SDG&E is continually dredging portions of the lagoon to ensure a constant source of cooling water and protect tidal flow. During the design phase of the proposed action, SDG&E concluded that beach fill placed south of Oak Street and north of Palomar Airport Road would result in potential blockage of the Agua Hedionda Lagoon inlet and warm water discharge. Therefore, the area between Oak Street and Palomar Airport Road was not considered as an alternative to the proposed action due to potential sediment accretion at the lagoon inlet and discharge area. 23.4 South Encinitas Alternative The South Encinitas Alternative includes the area from Moonlight State Beach to San Elijo State Beach (Figure 2-6). As referenced hi the Homeporting EIS (Section 3.1.2.4), qualitative (diver survey) observations were made in the vicinity of this alternative site. Surveys indicate that this area is constrained by the presence of intertidal and shallow subtidal vegetated reefs, which would be directly buried by onshore sand placement. Additionally, numerous reef-supported surf breaks exist in the vicinity of this beach segment, which could be adversely affected by beach replenishment. Therefore, due to direct impacts to sensitive marine resources and potential impacts to reef surf breaks, this alternative area was not considered further for beach replenishment. 23.5 San Elijo State Beach Alternative This alternative area includes San Elijo State Beach and extends from Swami's Park to the San Elijo Lagoon inlet (Figure 2-6). Similar to the South Encinitas Alternative site, this area was surveyed as part of the Homeporting EIS and consists of intertidal and shallow subtidal vegetated reefs. Therefore, fill placement at this site would cause direct burial of sensitive marine resources. This area also includes several popular reef- supported surf breaks that could potentially be adversely affected by fill placement. Furthermore, beach fill placed at San Elijo State Beach would be transported south hi a relatively short time, causing potential blockage of the San Elijo Lagoon inlet. Therefore, this alternative area was not considered further. 211603000 2-17 23.6 Del Mar Alternative The area referred to as the Del Mar Alternative includes the beach area from the San Dieguito Lagoon inlet to Torrey Pines State Beach within the jurisdiction of the City of Del Mar (Figure 2-6). As part of the Homeporting EIS, a near shore disposal site was permitted off the coast of the City of Del Mar (Figure 2-7). Sand disposed of at the Del Mar nearshore site would satisfy beach replenishment needs for the City of Del Mar. Therefore, since beaches within the City would not require beach replenishment beyond what would occur from nearshore disposal, this area was not considered further for onshore beach replenishment. 23.7 Torrey Pines Design Alternative Under the Torrey Pines Design Alternative, the Navy investigated a design that consisted of one contiguous beach stretching from the Torrey Pines State Reserve parking area to Flat Rock (Figure 2-6). This alternative would directly cover sensitive marine resources including intertidal and shallow subtidal vegetated reefs. In addition, sand transport modeling indicates that placement of a large volume of sand hi this area would cause blockage of the Los Penasquitos Lagoon inlet, thereby cutting off tidal exchange in the lagoon. This alternative was therefore rejected due to direct placement onto sensitive marine resources and blockage of the lagoon inlet. The Torrey Pines receiver site, as proposed, differs from the rejected Design Alternative because it would eliminate direct placement onto sensitive marine resources by creating two receiver areas for disposal, thereby avoiding sensitive resource areas that occur along Torrey Pines State Beach. Additionally, by creating two smaller fill areas, the potential for sand accretion at the lagoon mouth would be reduced. 23.8 Black's Beach Alternative The Black's Beach Alternative area extends from Flat Rock (at Torrey Pines State Beach/State Reserve) to Scripps Institute of Oceanography and includes the southern portion of Torrey Pines State Beach and Black's Beach (Figure 2-6). This area is in close proximity to the Scripps/La Jolla Submarine Canyon, which is located at the base of Mount Soledad north of La Jolla Point (FRH 1997). Beach fill placed along this segment would be transported offshore to the Scripps/La Jolla Submarine Canyon in a relatively 2-18 211603000 OeeansldeNearshore Site Buccaneer BeachAlternative Fill Site North CarlsbadFill Site South CarlsbadAlternative Fill Site South CarlsbadFill Site EnclnltasFill Site Del MarNearshore Site Torrey PinesFill Site FEET Mission Beach Nearshore Site Imperial BeachNearshore Site 9000 F I G U R E Beach Replenishment Sites 2-7 short time and lost from the littoral cell. Beach fill placed along Black's Beach would have a higher potential to be lost from the littoral cell than fill placed north of this site. Therefore, as the Black's Beach Alternative would not meet a key objective of the proposed action (i.e., addition of sand to the littoral cell), this alternative was not considered further. 23.9 Scripps Alternative The Scripps Alternative consists of the beach area from Scripps Institute of Oceanography to La Jolla Cove and includes the San Diego Marine Life Refuge, La Jolla Shores, and the La Jolla Ecological Reserve (Figure 2-6). Similar to the Black's Beach Alternative, this site is also in close proximity to the Scripps/La Jolla Submarine Canyon. Beach fill placed at this location would also be transported offshore and potentially lost from the littoral cell. This entire area is included within the La Jolla Underwater Park, which is a recreational area primarily used for diving. Segments of this beach area are also used for marine research by Scripps Institute of Oceanography. Due to potential loss of sand from the littoral cell, impacts to marine research efforts associated with Scripps Institute, and potential impacts to the La Jolla Underwater Park, the Scripps Alternative was not considered further. 2.4 No ACTION ALTERNATIVE Under the No Action Alternative, approximately 2,209,610 m3 (2,850,400 cy) of beach- compatible dredged materials would not be disposed of along beaches in Carlsbad, Encinitas, Torrey Pines, or Oceanside. Instead, the Navy would dispose of the material at nearshore sites that were identified and analyzed in the Homeporting EIS (Figure 2-7). Areas analyzed for nearshore disposal include Oceanside, Del Mar, Mission Beach, and Imperial Beach. A full environmental analysis of potential impacts to each of these nearshore sites has been evaluated in the Homeporting EIS. A Section 404/10 permit from ACOE was obtained by the Navy on April 6,1996 (Permit No. 94-20861-DZ) allowing the Navy to utilize the identified nearshore sites for dredged material disposal. Should the No Action Alternative occur, the dredged material would be disposed of at permitted nearshore sites as follows: 2-20 211603000 North Carlsbad receiver beach material would be placed at the South Oceanside nearshore disposal site. South Carlsbad receiver beach material would be placed at the South Oceanside nearshore disposal site. Encinitas receiver beach material would be placed at the South Oceanside nearshore disposal site (approximately 25 percent) and the Del Mar nearshore disposal site (approximately 75 percent). Torrey Pines receiver beach material would be placed at the Imperial Beach nearshore disposal site (approximately 25 percent) and the Mission Beach nearshore disposal site (approximately 75 percent). 211603000 2-21 This Page Intentionally Left Blank 2-22 211603000 SECTIONS AFFECTED ENVIRONMENT 3.1 GEOLOGY AND SOILS Existing geologic conditions are based on the Beach Sand Transport and Sedimentation Report prepared by Frederic R. Harris, Inc. (FRH 1997). This report provides general information and a regional perspective on coastal geology, beaches and shoreline configuration, tides and sea level changes, wave processes, and littoral processes. 3.1.1 Definition of Resource For purposes of this EA, geology and soils hi this study include coastal geology and littoral processes. Coastal geology and beach configuration are determined primarily by wave forces acting on the geologic framework. These factors account for the area's rugged undersea and land topography, including the narrow continental shelf, the rocky substrate under most beach areas, the thin layer of sediment, as well as coastal marine terraces, sea cliffs, and lagoons. The following subsections focus on the existing geologic conditions and littoral processes that make up the individual receiver sites. 3.1.2 North Carlsbad 3.1.2.1 Coastal Geology The North Carlsbad receiver beach was formed from sand and rocks that originated from upland erosion. The beach consists of a relatively thin sand lense, which varies in width and lies on a shallow, wave-cut bedrock platform. Unusually large waves can strip the rocky terrace clean by moving the sand offshore or downcoast. South of Buena Vista Lagoon, the existing beach is relatively narrow with an abundance of cobbles. The beach is backed by marine terraces that reach a height of approximately 10 m (30 ft). Beach widths from Oceanside Harbor to La Jolla are narrower than they were historically as a combined consequence of a net decrease of river sand inputs and the trapping effect of the Oceanside Harbor on the littoral transport of sand from the north. 211603000 3-1 3.1.2.2 Littoral Processes Beaches along the central and southern California coast are typically dynamic in nature, with constant and continual longshore and onshore/offshore sediment transport. These processes vary seasonally in intensity depending upon oceanographic and weather conditions, occurring both locally and throughout the Pacific Ocean region. Particles of sediment that are moved via this erosional process are typically suspended into the water column by wave or current action, transported some distance by longshore currents, and deposited on adjacent beaches. The void (or erosion) left behind by this movement is normally replenished by similar sediment that has been eroded from yet another beach area. Although this process gives the illusion of stationary beaches, the actual sediment constituting beaches is in a constant state of movement (ACOE 1994). The Oceanside Littoral Cell extends from Dana Point in Orange County, south to the Scripps-La Jolla Submarine Canyon system at La Jolla Shores near the foot of Mount Soledad. The Oceanside Harbor complex is located in the approximate midpoint of this cell. Harbor jetties interrupt the natural flow of sand and to a large extent divide the cell into a sub-cell north of Oceanside Harbor. Receiver beaches are located along the southern half of the Oceanside Littoral Cell. Historical longshore transport rates and shoreline changes are documented in the Coast of California Storm and Tidal Waves Study (CCSTWS) (ACOE 1991). This study concluded that the future condition of beaches in northern San Diego County would be governed by cycles of accretion and erosion similar to those of the past 50 years, with accelerated trends toward erosion due to the following conditions: (1) reduction of river- borne sediment due to impoundment by dams, (2) influence of Oceanside Harbor, and (3) increase in the rate of sea level rise. Extensive studies of longshore sediment transport rates have been conducted on the Oceanside Littoral Cell. Table 3-1 summarizes sediment transport rates, as identified by previous researchers. Results indicate a net southerly sediment transport at a rate ranging between 78,000 and 194,000 m3/yr (or approximately 100,000 to 250,000 cy/yr). 3-2 211603000 Table 3-1 LONGSHORE SEDIMENT TRANSPORT RATE ESTIMATES FOR THE OCEANSIDE LITTORAL CELL Study Marine Advisers (1961) Hales (1978) Inman and Jenkins (1983) Northerly mVyr (ydVyr) 416,700 (545,000) 413,600 (541,000) 422,800 (553,000) Southerly rnVyr (yd3/yr) 581,100 (760,000) 491,600 (643,000) 617,000 (807,000) Net m3/yr(yd3/yr) 164,400 (215,000) 78,000 (102,000) 194,200 (254,000) Source: Frederic R. Harris, Inc. 1997 Historical sources of sediment for Oceanside Littoral Cell beaches include rivers, streams, and lagoons. However, since the 1950s, dams have significantly reduced these sediment sources. Furthermore, urbanization has accelerated the erosion rate of coastal bluffs and increased the rate of sedimentation in lagoons. Thus, current sources of onshore littoral material primarily include rivers, bluffs, and artificial fills. Several other elements also contribute to the decline of sediments within the littoral cell. Storms carry sediment away from the nearshore area and deposit it on the continental shelf. Due to the steepness of the Oceanside Littoral Cell shelf, littoral material can be permanently lost from the littoral zone. Additionally, littoral transport between Oceanside and La Jolla is affected by two submarine canyons located at Carlsbad and La Jolla, which act as significant sediment sinks for littoral material. However, the North Carlsbad site is located north of these submarine canyons; thus, littoral transport at this receiver site would not be as affected as beaches to the south. Because of the reduction in littoral material sources, and the loss of material due to storms and submarine canyons, 211603000 3-3 there has been a net reduction in available natural sources of beach replenishment at the North Carlsbad receiver beach. 3.13 South Carlsbad 3.13.1 Coastal Geology The South Carlsbad receiver site is located on a low tide terrace, which lies hi front of coastal cliffs between Agua Hedionda Lagoon and Batiquitos Lagoon. The steep coastal cliffs in this area have been continually forming from wave action cutting against the marine terrace. This process has occurred since the last relative still-stand of sea level, approximately 6,000 years ago (FRH 1997). The existing beach comprises the flat, rocky, shallow part of the shoreline. 3.1.3.2 Littoral Processes The South Carlsbad receiver beach is within the Oceanside Littoral Cell which is subject to similar transport processes as those described hi Section 3.1.2.2 and is located within a critical erosional area (ACOE 1991). Additionally, this site is located south of the Carlsbad Submarine Canyon, which may act as a sediment sink, thereby reducing the amount of littoral transport to the area (FRH 1997). 3.1.4 Encinitas 3.1.4.1 Coastal Geology The Encinitas receiver site is located on a low tide terrace, which lies hi front of coastal cliffs south of Batiquitos Lagoon. The steep coastal cliffs hi this area have been continually forming from wave action cutting against the marine terrace. The existing beach comprises the flat, rocky, shallow part of the shoreline visible during periods of low tide. Batiquitos Lagoon was formed in the geologic past when the sea level was at a lower level, the shoreline was located further to the west, and existing streams quickly eroded the exposed marine terraces. This led to the formation of steep canyons and as the sea level rose (approximately 18,000 years ago), sediments quickly filled the lower reaches of 3-4 211603000 the channels that created the lagoon. Batiquitos Lagoon is currently a tidal lagoon due to an enhancement project completed in early 1997 that opened the inlet channel to tidal flows. 3.1.4.2 Littoral Processes The Encinitas receiver beach is located within the Oceanside Littoral Cell and is subject to similar transport processes as those described in Section 3.1.2.2. The Encinitas receiver beach is located within a critical erosional area (ACOE 1991). Additionally, this site is located south of the Carlsbad Submarine Canyon, which may act as a sediment sink, thereby reducing the amount of littoral transport to the area (FRH 1997). 3.1.5 Torrey Pines 3.1.5.1 Coastal Geology The northern and southern Torrey Pines receiver beaches are located on a low tide terrace, which lies hi front of coastal cliffs to the north and south of Los Penasquitos Lagoon. The steep coastal cliffs in this area have been continually forming from wave action cutting against the marine terrace. The existing beach comprises the flat, rocky, shallow part of the shoreline visible during low tide. Similar to Batiquitos Lagoon, Los Penasquitos Lagoon was formed in the geologic past when the sea level was lower, the shoreline was located further to the west, and existing streams quickly eroded the exposed marine terraces. Los Penasquitos Lagoon is an intermittent tidal lagoon due to occasional lagoon closures from sediment accretion at the channel inlet. 3.1.5.2 Littoral Processes The Torrey Pines receiver sites are both within the Oceanside Littoral Cell and are subject to similar transport processes as described hi Section 3.1.2.2. According to the CCSTWS, the Torrey Pines receiver beaches are not located within a critical erosional area. The Torrey Pines receiver sites are located south of the Carlsbad Submarine Canyon, which may act as a sediment sink, thereby reducing the amount of littoral transport to these areas (FRH 1997). 211603000 3-5 3.1.6 Buccaneer Beach/South Carlsbad Alternative 3.1.6.1 Coastal Geology Geologic characteristics of the Buccaneer Beach alternative receiver site are similar to those of the North Carlsbad receiver site due to their directly adjacent locations. Existing geologic conditions at the Buccaneer Beach site are described in Section 3.1.2.1. Similarly, the geologic characteristics of the proposed additional fill associated with the South Carlsbad alternative site are described in Section 3.1.3.1. 3.1.6.2 Littoral Processes The alternative receiver sites are within the Oceanside Littoral Cell and are subject to similar transport processes as described in Section 3.1.2.2. The Buccaneer Beach and South Carlsbad alternative receiver sites are located within a critical erosional area (ACOE 1991). Littoral transport to the Buccaneer Beach site would not be affected by the Carlsbad Submarine Canyon due to its location north of the canyon; however, the South Carlsbad receiver site is located south of the Carlsbad submarine canyon, which may act as a sediment sink, thereby reducing the amount of littoral transport to this area (FRH 1997). 3.2 COASTAL WETLANDS 3.2.1 Definition of Resource Coastal wetlands discussed in this report include creeks, rivers, or lagoons that discharge into the ocean near the proposed receiver sites (FRH 1997). Coastal wetland areas identified in the vicinity of the proposed receiver sites include San Luis Rey River, Loma Alta Creek, Buena Vista Lagoon, Agua Hedionda Lagoon, Encinas Creek, Batiquitos Lagoon, San Elijo Lagoon, San Dieguito Lagoon, and Los Penasquitos Lagoon. Each of these coastal wetland areas is described below. 3-6 211603000 This section provides a brief overview of coastal wetland areas in the vicinity of the proposed action. For a more detailed discussion of coastal wetlands, refer to the Beach Sand Transport and Sedimentation Report by FRH (1997). 3.2.2 San Luis Rey River The San Luis Rey River has a watershed area of 1,445 square (sq) km (560 sq mi) and is located below Lake Henshaw Dam. It has been estimated that construction of the dam has reduced the average sediment yield of the river by approximately 32 percent. The San Luis Rey River has historically received discharges of treated wastewater. The ocean inlet at this location is open intermittently due to the presence of a sand barrier and low freshwater flows. The wetland area adjacent to the ocean inlet consists of approximately 300 acres, of which 52 acres are open estuarine lagoon waters. This wetland is primarily a fresh/brackish water habitat. The dominant habitat adjacent to the ocean inlet is riparian, which occupies approximately 130 acres. Saltwater and freshwater marsh habitats are also adjacent to the ocean inlet. Endangered species that forage or nest hi this area include California least tern and California brown pelican. Least Bell's vireo also nest in adjacent riparian habitat. No endangered species are known to nest directly on the beach at the San Luis Rey River. 3.23 Loma Alta Creek Loma Alta Creek, which discharges south of the proposed beach fill area, is a seasonal freshwater creek, but suffers from urbanization and poor water quality (City of Oceanside 1985). The outlet area crosses a small steep sand beach that is defined by rip-rap on both sides. A small freshwater marsh is located east of the outlet area. During the dry season, when the creek is not running, the outlet is closed to the ocean by a sand berm (FRH 1997). 3.2.4 Buena Vista Lagoon Buena Vista Lagoon, located south of the receiver beach, is the smallest of the area lagoons. Historically, Buena Vista Lagoon had 376 acres of low marsh and 290 acres of high marsh habitat; however, it presently consists of a 246-acre fresh/brackish water wetland area (MEC 1993). The lagoon has historically received discharges of secondary treated wastewater and presently continues to experience sewage spills. The accumulated 211603000 3-7 sludge, plant detritus, excess nutrients, and contained basin combine to cause eutrophic conditions. Nonetheless, a diverse assemblage of sensitive bird species (e.g., California least tern, Belding's savannah sparrow, and California brown pelican) forage or nest in the vicinity of this lagoon (MEC 1993). However, none of these sensitive species are known to nest on the beach in front of the lagoon due to high recreational use of this beach segment. The lagoon is managed by the CDFG as a State Ecological Reserve. Buena Vista Lagoon is no longer connected to the ocean due to the construction of a fixed weir in 1940, which was designed to provide a year-round aquatic environment. Excess seasonal freshwater runoff flows over the weir to the ocean. The weir is located in the back end of a small pocket beach, approximately 44 m (145 ft) behind the crest of a longshore cobble berm. High tides do not usually wash over the weir; however, evidence suggests that high waves occasionally overtop the weir during the winter. 3.2.5 Agua Hedionda Lagoon The ocean inlet to Agua Hedionda Lagoon is located south of the proposed North Carlsbad receiver site and north of the proposed South Carlsbad receiver site. Agua Hedionda is of particular interest because it has been a tidal lagoon since 1954 when San Diego Gas and Electric completed a 3.3 million m3 dredging project to provide a deep water basin and cooling water source for the Encina Power Plant. As a result, the lagoon exhibits a diverse community of marine benthic invertebrates and fish (Bradshaw et al. 1976). The lagoon supports a number of uses including bivalve and fish aquaculture, recreational boating and skiing, fishing and clamming, and a marina. Two pairs of jetties maintain tidal flow and power plant circulation; the northern jetties serve as an ocean inlet to the lagoon and the southern jetties serve as the warm water discharge flow from the power plant. Agua Hedionda Lagoon has a total wetland area of approximately 390 acres, of which 250 acres are open estuarine waters. The lagoon has a relatively small watershed area consisting of 185 acres. Sedimentation has been a problem in the lagoon, occurring from both tidal and freshwater flows. The west basin of the lagoon is dredged approximately every 2 years to sustain tidal flushing and to ensure a source of cooling water for the Encina Power Plant. Dredged sediments are typically discharged hi front of the power plant between the ocean inlet and the warm water discharge canal, and south of the warm water discharge canal. Agua Hedionda is a deep lagoon with limited shallow water areas 3-8 211603000 or intertidal habitats. Consequently, it is a unique wetland because it supports 70 acres of eelgrass and only 4 acres of salt marsh. Although species diversity is low, a number of sensitive species (including California least tern and Belding's savannah sparrow) have historically nested and/or foraged in the lagoon area; however, no sensitive species are known to nest directly on the beach in front of the lagoon (FRH 1997). 3.2.6 Encinas Creek Encinas Creek is a narrow, seasonal freshwater creek that discharges into the ocean in the vicinity of the Encina Wastewater Treatment Plant and approximately 300 m (985 ft) north of the proposed South Carlsbad receiver site. The creek drains a former agricultural area and the Palomar Business Park near El Camino Real. The creek passes under Carlsbad Boulevard through two cement culverts. East of Carlsbad Boulevard, the channel widens to include 4.2 acres of freshwater marsh. Stormwater runoff typically flows across a cobble berm and sand beach and often creates a turbidity plume in the nearshore zone. High tides occasionally reach the western of the two culverts under Carlsbad Boulevard but are not known to reach the freshwater marsh area (FRH 1997). 3.2.7 Batiquitos Lagoon Batiquitos Lagoon inlet is located south of the proposed South Carlsbad receiver site and north of the proposed Encinitas receiver site. The lagoon is managed by the CDFG as an ecological reserve. A major wetlands enhancement project that involved dredging the entire lagoon was completed in January 1997, which allowed sustained tidal flushing of the lagoon. Prior to the enhancement project, the lagoon consisted of 550 acres of shallow wetland, which included estuarine open water, southern coastal salt marsh, and tidal estuarine flats. The lagoon area supported a number of nesting migratory birds, including California least terns and western snowy plovers. The lagoon had been subjected to frequent inlet closures due to the buildup of a sand and cobble berm. The lagoon closures led to a substantial accumulation of organics and fine anaerobic sediments, persistent eutrophic conditions, development of extensive algal mats, and wide swings in salinity. Since completion of the enhancement project, habitats throughout the lagoon have been altered. Consequently, the lagoon is currently in a transition phase, and it is not possible to represent its hydrological performance, ecological status, or to what extent the habitat 211603000 3-9 restoration efforts will succeed. Sediments dredged from the lagoon were placed onshore north and south of the inlet, which covered an extensive longshore cobble berm that had been responsible for lagoon closures. Over time, the beach fill associated with the lagoon dredging project will erode and the cobble berm will become active again. The new ocean inlet to the lagoon is protected by two jetties that enable sustained tidal flushing. Due to the dynamics of the lagoon, the west and central basins are expected to accumulate beach sand and will require routine maintenance dredging similar to that conducted at Agua Hedionda Lagoon every 2 years (FRH 1997). 3.2.8 San Elijo Lagoon The San Elijo Lagoon inlet is located approximately 6.4 km (4 mi) south of the proposed Encinitas receiver beach. San Elijo Lagoon is comprised of approximately 900 acres and includes the 590-acre San Elijo Lagoon Ecological Reserve, which is managed by the CDFG and the San Diego County Department of Parks and Recreation. The lagoon supports a multitude of habitats, including coastal salt marsh, tidal channels, mudflats, and freshwater marsh habitats. Adjacent to the wetland are upland chaparral and riparian habitats. Sensitive bird species known to nest and forage hi this area include California least tern, western snowy plover, and Belding's savannah sparrow (MEC 1993). The western snowy plover has historically nested along the beach in front of the lagoon; however, due to a reduction in beach area over the past decade, this sensitive bird is no longer known to nest on the beach at this location. Habitat quality has been degraded from changes in hydrology, land use surrounding the watershed, urbanization, sedimentation resulting in poor water quality, introduction of exotic species, and severely limited tidal action (County of San Diego 1995). A combination of these effects has resulted in regular closures of the lagoon mouth. 3.2.9 San Dieguito Lagoon San Dieguito Lagoon is located approximately 1.6 km (1 mi) south of Fletcher Cove Beach park. The lagoon includes a lengthy river channel, which serves as the main body of the lagoon, along with a channel tributary. Historically, the lagoon was a 604-acre salt marsh but was filled hi to construct the Del Mar fairgrounds and racetrack in 1935. Today, San Dieguito Lagoon is primarily a river channel with dominant seasonal fluvial flows. The watershed consists of the San Dieguito River and its tributaries; however, 3-10 211603000 Lake Hodges Dam restricts storm flows on the river, affecting the natural function of the lagoon. During drought periods, the ocean inlet is typically closed. During wet years, storm flows would blow out the ocean inlet barrier and scour the river bed in the lagoon. Wastewater discharges and sewage spills have occurred hi the lagoon and have contributed to increased eutrophic conditions. The wetland acreage of the lagoon totals 520 acres; however, 259 acres consist of highly disturbed, agricultural, and nonvegetated habitat. The lagoon serves as nesting and foraging habitat for several shorebirds and water fowl. No sensitive bird species are known to nest on the beach in front of San Dieguito Lagoon due to its high recreational use. 3.2.10 Los Pefiasquitos Lagoon Los Pefiasquitos Lagoon inlet is located between the proposed northern and southern Torrey Pines receiver sites. The lagoon has a total wetland area of 217 acres and includes southern coastal salt marsh habitat, riparian habitat, and tidal channels. The watershed is of moderate size at 625 acres; however, it has become increasingly hardened with construction of industrial sites and urban development, which has accelerated stormwater runoff to the lagoon. The Los Pefiasquitos Lagoon Foundation has been successfully experimenting to keep the ocean inlet open and enable sustained tidal flushing. However, the presence of a longshore cobble berm adjacent to the ocean inlet complicates maintenance of tidal exchange. Transport and deposition of cobbles into the inlet and main lagoon channel accelerates inlet closure processes. Historically, the lagoon has received discharges of secondary treated wastewater and accumulated deposits of sludge, plant organic detritus, and fine sediments. Several large sewage spills have occurred hi recent years, which has led to the recent replacement of a sewage pump station located within the lagoon. Substantial accumulation of sediments throughout the lagoon has reduced tidal flushing, resulting hi degraded water quality conditions, degradation of salt marsh habitat, establishment of invasive plant species, and mortality of benthos and fish. A fresh/brackish water marsh, supported by freshwater flows from Cannel Creek, is located adjacent to Interstate 5 (1-5). Ongoing construction of the new State Highway 56/1-5 interchange has increased turbidity and sedimentation in the lagoon. A number of endangered bird species forage and nest in the vicinity of Los Pefiasquitos Lagoon, including California least tern, Belding's savannah sparrow, and western snowy 211603000 3-11 plover; however, none of these sensitive species are known to nest on the beach in front of the lagoon. Endangered plant species identified within the lagoon include salt marsh daisy, southern poverty weed, and beach deerweed. Tidal flushing and storm runoff are the major sources of sediment input to the lagoon. Tidal inflow transports marine sand and cobbles into the main channel where they accumulate, reduce tidal flushing, and may cause lagoon closure. When the lagoon closes, water quality deteriorates rapidly, leading to fish kills and insect production. Stormwater transport and sediment deposition varies greatly with the rate of precipitation and storm frequency and intensity. Urban development in the vicinity of the lagoon has facilitated year-round runoff and the growth of fresh/brackish water habitat (including invasive plant species), primarily along Carmel Canyon Creek adjacent to 1-5. 3.3 WATER RESOURCES 33.1 Definition of Resource Water resources analyzed in this study include physical processes and chemical properties. Physical processes include tides and water levels, currents, wave exposure, and littoral processes. Chemical properties are characterized by temperature, salinity, dissolved oxygen, and water visibility (turbidity). The following is a discussion of the factors that contribute to the quality of existing water resources at each of the proposed receiver beaches. 3.3.2 Physical Processes Southern California has a mixed semidiurnal (daily) tide with two high tides and two low tides, each of different magnitude, every 24 hours and 50 minutes. The range between mean high and low water is approximately 1.1 m (3.7 ft) and the diurnal range is approximately 1.6 m (5.4 ft). Tidal characteristics in the vicinity of the proposed receiver beaches range from a lowest observed tide of -1.6 m (-5.4 ft) MSL to a highest observed tide of+1.5 m (+5.1 ft) MSL (ACOE 1996b). Local currents in nearshore waters are complex and include longshore currents, which flow parallel to the shore, and cross-shore currents, which move in an onshore-offshore 3-12 211603000 direction. The combination of these currents makes up the littoral transport process. Longshore currents in the coastal zone are driven primarily by waves striking the shoreline at oblique angles. Overall, longshore currents produce drift and sediment transport from north to south. Wave exposure affects the receiver beaches from the south and west. For further discussion of littoral transport processes affecting the proposed receiver sites, refer to Section 3.1. 333 Chemical Properties Due to the local physical characteristics of the area, the water column is well mixed vertically, with seawater temperatures ranging between 13.9 and 23.9 degrees Celsius (57 and 75 degrees Fahrenheit). Salinity in the coastal area typically varies between 33 and 3 5 parts per thousand (ACOE 1996b). High dissolved oxygen concentrations are maintained by tidal and wave action, while low concentrations result from respiration by aquatic organisms, poor circulation, and oxidation of organic matter. A dissolved oxygen level equal to or greater than 5 parts per million (ppm) has been recommended as a generalized standard of acceptable water quality for aquatic life (EPA 1986). Dissolved oxygen concentrations are routinely measured off the coast of Encinitas, approximately 12.8 km (8 mi) south of the North Carlsbad receiver site, 3.2 km (2 mi) south of the South Carlsbad receiver site, and 14.5 km (9 mi) north of the Torrey Pines receiver site. Average recorded dissolved oxygen levels are 10 ppm (ACOE 1996b). 33.4 Turbidity Turbidity refers to the total amount of suspended sediments in the water column. Increases hi turbidity can affect fish growth, propagation, feeding, and respiration. Turbidity is caused by the presence of fine sediments (e.g., silts and clays) in the water column. It reduces the transparency of seawater and therefore reduces the amount of light available for phytoplankton and photosynthesis. Suspended silt particles in the water column will increase turbidity; however, larger sand particles (>63 micrometers Qim]) will settle out rapidly and do not cause a significant increase hi turbidity. Testing of the dredged material suitable for beach disposal determined that approximately 97 percent of the sand is greater than 63 um (Navy 1996). Sampling of the water near the receiver beaches indicates that nearshore water visibility typically ranges between 1.5 and 6 m 211603000 3-13 (5 and 20 ft) (ACOE 1996b); however, visibility is significantly reduced in the surf zone due to sediment disturbance from wave action. Therefore, intertidal waters of the receiver beaches are characteristically turbid due to the high energy activity in the nearshore environment. 3.4 BIOLOGY 3.4.1 Definition of Resource The following section provides an introduction to the existing biological communities occurring within the proposed alternate receiver areas. Habitat and biological descriptions are based on field studies of the proposed fill areas at each receiver site using both fathometer and diver surveys. Marine biological field surveys were performed to identify and map the locations of sensitive marine resources. Sensitive marine resources are defined as rocky intertidal reefs, subtidal vegetated reefs that contain feather boa kelp (Egregia menzesif), surfgrass (Phyllospadix torreyf), and sea palms (Eisenia arbored), and nearshore reefs with giant kelp (Macrocystis pyriferd). Reefs that support sea fans (Muricea spp.) are also considered sensitive because sea fans are indicative of persistent reefs that are not covered by sand. The intertidal zone is defined as the area between the highest high tide and the lowest low tide and can be divided into three areas (upper, middle, and lower) based on the frequency and duration of inundation by seawater. The intertidal zone is also characterized by breaking surf. Shallow subtidal zone is defined as the area between the lower intertidal and the nearshore zone. The nearshore zone is defined as the subtidal zone between -6 m and -33 m (-20 ft and -100 ft) MSL. Fathometer surveys were designed to identify the location of different habitat types (i.e., sand and rock reefs) and also to differentiate between different topographical features (i.e., flat sandy areas, and low and high relief reefs) within the predetermined disposal footprint at each of the six potential receiver beaches. Low relief reefs are defined as reefs that extend less than 1 m from the sand surface; high relief reefs are defined as reefs that extend greater than 1 m from the sand surface. When elevated reef areas were identified on the fathometer, divers made bounce dives (dives of <5 minutes) to 3-14 211603000 determine the elevation of the reefs. Locations of the reefs were mapped using a Differential Geographic Positioning System (DGPS) and plotted on a map with an accuracy of 2 to 3 m. (6.6 to 10 ft). Fathometer surveys also enabled marine biologists to (1) cover large areas of the shallow subtidal zone at each receiver beach; (2) identify the locations of the different habitat types and bathymetry of the seafloor; and (3) identify areas where sensitive marine resources may exist. In areas where sensitive marine resources were identified, divers swam transects to describe the species composition of the reefs and map the extent of the sensitive marine resources. Divers attached a metered tape to the anchor and swim a predetermined compass heading. Qualitative assessments of habitat type and species composition of eight reefs per disposal footprint at each beach site were performed. Transects were run in a rrunimum of three directions. In general, one transect was oriented towards the shoreline (east) and two transects parallel to the shoreline (upcoast and downcoast). 3.4.2 North Carlsbad The North Carlsbad receiver area is located north of Agua Hedionda Lagoon and is characterized by sandy beaches in the intertidal zone, and hard substrates (i.e., low and high relief reefs) interspersed among sand channels in the shallow subtidal zone. Organisms that live within the intertidal have adapted to a continually changing environment and physical factors such as grain size, slope of the beach, turbidity, and wave action. These organisms also have physical tolerances (e.g., desiccation) which influence species diversity, abundance, and distribution. Sand Habitats Beach hoppers (Orchestoidea), the predatory isopod Excirolana chiltoni, and three species of polychaete worms are commonly found in the upper intertidal zone (Thompson et al. 1993). Sand crabs (Emerita analoga) are common hi the middle intertidal zone but move with the tide throughout the intertidal area. Polychaetes, snails, and the bean clam (Donax gouldi) are also found in the middle intertidal zone. Tubicolus polychaete (Diopatra ornata and D. splendissimd) and nemertean worms dominate the lower intertidal area (Straughan 1982). 211603000 3-15 Areas that are permanently inundated by seawater are defined as subtidal. California corbina (Menticirrhus undulatus) and barred surfperch (Amphistichus argenteus) are common in shallow subtidal areas, often darting into the surf zone to feed on sand crabs. Other fishes that commonly occur over sandy bottoms include topsmelt (Atherinops affinis), queenfish (Seriphus politus), spotfin croaker (Roncador stearnsii), white croaker (Genyonemus lineatus), California halibut (Paralichthys californicus), shovehiose guitarfish (Rhinobatosproductus), and round stingray (Urolophus halleri) (ACOE 1994). Large (visible) algae are not found on sandy substrates. Phytoplankton (planktonic forms of algae) do occur in the water column at North Carlsbad. However, phytoplankton abundance is seasonal and has not been measured. California grunion (Leuresthes tenuis) may be found seasonally in the nearshore waters of the North Carlsbad receiver site. Grunion typically utilize sandy beach areas for spawning (runs) from March through mid-September with peak activity between April and June; however; due to their unique spawning behavior along the coast, exact locations where spawning will occur cannot be determined. Grunion spawn only on 3 or 4 nights after the highest high tide associated with each full or new moon. They are considered a "Species of Special Concern" due to their unique spawning behavior and are managed as a game species by the CDFG. Based on expected grunion runs for 1997, spawning is not expected to occur during sand replenishment activities. Reef Habitats The shallow subtidal zone also contains low relief and high relief reefs that are scattered among sand channels (Figure 3-1). Reefs are made of hard substrate (rock or sandstone), are elevated above the sand, and provide increased surface area and crevices for species to seek refuge. Consequently, the reefs are home to more species than the sandy substrates. Sessile invertebrates and algae attach to the reefs, while the reef crevices provide habitat for fishes and invertebrates. Vegetated reef habitat is considered a sensitive marine resource by NMFS, USFWS, and CDFG because the reefs support surfgrass and macro algae that act as habitat for smaller species of algae, fishes, and invertebrates. Reef habitats are found primarily in the southern part of the receiver beach. 3-16 211603000 Buccaneer BeachAlternative Fill Site Feathei Boaand Sea nvegetated Giant Kelp e> Feather Boa KelpLEGEND SAND Feather Boa Kelp LOW RELIEF SCATTERED REEF HIGH RELIEF REEF Historical MaximumKelp Bed Canopies1978 to 1996 Kelp Bed Canopy1997 Mono Buoy L"L~;1! Offshore Restricted Zone /V Fill Area /V Sinker Line A/ Railroad Scattered Surf grass Surf grass Feather Boa Kelp F I G U R E North Carlsbad/Buccaneer Beach Biological Resources tiotifo«<ttploti'Btu»i/li«l>itiUml 03/1H97 Only about 19 percent of the shallow subtidal reef habitats are vegetated. Vegetated reefs are initiated by species of red (fleshy and coralline), green, and brown algae including feather boa kelp. Surfgrass beds also exist on low relief reefs near the receiver beach area (Figure 3-1). Giant kelp is not found on the shallow subtidal reefs. Historically, large beds of giant kelp were present on the nearshore (> 6 m deep) reef substrates of North Carlsbad; however, surveys conducted in 1996 found smaller and fewer kelp beds. The spatial extent of historic kelp growth in the North Carlsbad receiver area is shown in Figure 3-1. Invertebrate diversity is expected to be higher on the hard substrates and include sessile species such as mussels, burrowing clams, tube worms (Family Serpulidae), sponges, and bryozoans. Mobile species consist of lobsters (Panuliris interruptis), crabs (Cancer spp. and Lochoryncus sp.), sea urchins (Strongylocentrotus spp.), sea stars (Pisaster spp., Asterina miniatd), and gastropods (e.g., snails, limpets, and sea slugs). Numerous fish species that are important to recreational fisherman occur offshore of the North Carlsbad receiver site. Fish diversity and abundance within reefs and kelp beds are influenced by the presence or absence of kelp and substrate relief (Cross and Allen 1990). Kelp beds are not important spawning areas for fish but do provide refuge and foraging areas for juveniles and adults (Cross and Allen 1990). California sheephead (Semicossyphus pulcher), garibaldi (Hypsypops rubicundus), blacksmith (Chromis punctipinnis), rockfish (Sebastes spp.), kelp bass (Paralabrax clathratus), surfperch (Family Embiotocidae), and opaleye (Girella nigricans) are commonly found near kelp beds and rocky reefs. Marine Mammals California sea lions (Zalophus californicanus) and harbor seals (Phoca vitulind) occur offshore and may, infrequently, use the beach. Dolphins and porpoises have been observed offshore and within the surf zone of the North Carlsbad receiver beach. Birds Numerous shorebird species forage in the intertidal zone of the North Carlsbad receiver area, a majority of which are winter visitors. Species that may be seen in the North 211603000 3-19 Carlsbad receiver area include American avocet (Recurvirostra americand), black-bellied plover (Plitvialis squatarold), greater and lesser yellowlegs (Tringa melanoleuca and T.flavipes), spotted sandpipers (Actitis macularid), willets (Catoptrophorus semipalmatus), long-billed curlews (Numenius americanus), marbled godwit (Limosa fedod), and sanderlings (Calidris alba). Western gulls (Larus occidentalis), California gulls (Larus californicus), ring-billed gulls (Larus delewarensis), and herring gulls (Larus argentatus) are also common at the North Carlsbad receiver area. Sensitive bird species are those that are listed by the USFWS or CDFG as threatened or endangered, are proposed for listing as threatened or endangered, or are considered a "Species of Special Concern" by the CDFG. Sensitive birds that may occur at the North Carlsbad receiver area include the California brown pelican, California least tern, and western snowy plover. The federally and state-listed endangered California brown pelicans have been observed in the vicinity of the North Carlsbad receiver site, and forage and rest in nearshore waters. This species is tolerant of human activity near its daytime roosts and readily utilizes various man-made structures (e.g., piers, breakwaters, buoys) as roosting sites. Brown pelicans breed at the Coronado Islands, which are approximately 35 mi (56 km) south of the North Carlsbad receiver site. The federally listed (endangered) California least tern is a migratory bird that visits southern California's coastline from April through mid-September. This species breeds in open, unvegetated sandy areas and forage on small fish hi nearshore waters near their breeding colonies. California least terns are not expected to nest at the North Carlsbad receiver site due to the presence of humans; however, they may forage in the nearshore waters. The federally listed (threatened) western snowy plover nests hi flat open areas with sandy or saline substrates such as bays and lagoons. Breeding typically occurs from March to mid-September. Snowy plovers forage on invertebrates hi the intertidal zone. Western snowy plovers have not historically occurred along the North Carlsbad receiver site and are not expected to nest in the area due to high human presence. 3-20 211603000 3.4.3 South Carlsbad The South Carlsbad receiver site is located about 3 km (1.9 mi) south of the North Carlsbad receiver beach, south of Agua Hedionda Lagoon. The habitat and biological resources of the South Carlsbad receiver beach are similar to North Carlsbad. Sand habitat The upper intertidal is characterized by sandy beach habitat that extends into the middle and lower intertidal zones. The invertebrate and fish species inhabiting the sandy areas are similar to those found at North Carlsbad. Reef Habitat Low and high relief reef habitats are scattered throughout the shallow subtidal zone. The majority of the low relief reefs are vegetated with scattered patches of surfgrass, whereas the high relief reefs are vegetated with feather boa kelp, sea palms, and surfgrass (Figure 3-2). Giant kelp is not found on the shallow subtidal reefs; however, it is found in small patches on the deeper nearshore reefs. Surveys conducted in 1997 found smaller and fewer kelp plants than the historical maximum. The spatial extent of historic kelp growth in the South Carlsbad receiver area is shown in Figure 3-2. Invertebrate and fish species inhabiting the reef areas are similar to those found at North Carlsbad. Marine Mammals The South Carlsbad receiver beach is utilized by the same species of marine mammals as the North Carlsbad site. Birds The presence or absence of both sensitive and nonsensitive bird species and the potential for these species to utilize the South Carlsbad receiver site is similar to North Carlsbad. 211603000 3-21 3.4.4 Encinitas The Encinitas receiver site is located just south of the South Carlsbad receiver site and south of Batiquitos Lagoon. The habitats and biological resources found at the Encinitas receiver beach are similar to the North Carlsbad and South Carlsbad sites; however, the Encinitas site has substantially more reef habitat that extends from the shallow subtidal to the upper intertidal zone. Sand Habitat The upper intertidal is characterized by sandy beach and cobble habitats that extend into the middle and lower intertidal zones. The invertebrate and fish species inhabiting the sandy areas are similar to those found at North Carlsbad. Reef Habitat The middle and lower intertidal zones have low relief scattered reefs that are connected to the shallow subtidal reefs. In addition, low and high relief reef habitats are scattered throughout the shallow subtidal zone. The majority of the low relief reefs are vegetated with patches of surfgrass. High relief reefs are vegetated with giant kelp, feather boa kelp, sea palms, and surfgrass (Figure 3-3). Based on the species compositions that predominate the low and high relief reefs at Encinitas, the reefs appear to be perennial and show no signs of being covered and uncovered by sand. Although surveys conducted in 1997 found smaller and fewer kelp beds than the historical maximums, Encinitas has larger patches of giant kelp than the other receiver beach locations. In addition, giant kelp is also found in the shallow subtidal zone. The spatial extent of historic kelp growth in the Encinitas receiver beach is shown on Figure 3-3. Invertebrate and fish species inhabiting the reef areas are similar to those found at the other receiver beach sites. 3-22 211603000 LEGEND SAND vi VJSJ\i •-• VLOW RELIEF SCAHERED REEF HIGH RELIEF REEF COBBLE/SAND Historical MaximumKelp Bed Canopies1978I0199B Kelp Bed Canopy1997 4- Mono Buoy L1TJ Offshore Restricted Zone /V Fill Area /V sinker Line Ax Railroad Enclnltas Biological Resources OJ/1IW7 Feather Boa Kelp and Sea Balms South Carlsbad Alternative Fill Site Scattered Surfgrass ScatteredFeather Boa Kelp and Surfgrass LOW RELIEF SCATTERED REEF HIGH RELIEF REEF Historical MaximumKelp Bed Canopies1978 to 1998 Kelp Bed Canopy1997 4 Mono Buoy L1~U Offshore Restricted Zone /V Fill Area Sinker Line Railroad Northern Survey Boundaryfor Endrdtas FID Site South Carlsbad Biological Resources OS/HOT Marine Mammals The Encinitas receiver beach is utilized by the same species of marine mammals as the North Carlsbad and South Carlsbad sites. Birds The presence or absence of both sensitive and nonsensitive bird species and the potential for these species to utilize the Encinitas receiver site is similar to North Carlsbad and South Carlsbad. 3.4.5 Torrey Pines The Torrey Pines receiver beach is divided into two receiver sites located along Torrey Pines State Park. The habitats and biological resources found at the Torrey Pines receiver beaches are similar to the other receiver sites. Sand Habitat The intertidal and shallow subtidal zones of the northern receiver beach consist entirely of sand habitat. The northern portion of the southern site is entirely sand. The algae, invertebrate, and fish species that inhabit the sandy areas are similar to those found at the other receiver beaches. Reef Habitat Low and high relief reef habitats are found hi the southern portion of the shallow subtidal zone at the south receiver site. The majority of the low relief reefs are vegetated with scattered patches of surfgrass and feather boa kelp. The high relief reefs are vegetated with feather boa kelp, sea palms, and dense surfgrass (Figure 3-4). Giant kelp is only present in one small patch offshore of the southern portion of the south site. Historical maximums for giant kelp beds indicate that kelp beds have existed at the north Torrey Pines receiver beach, but as of the 1997 survey these beds no longer exist. The spatial extent of recent and historic kelp growth at the Torrey Pines receiver beaches is shown in Figure 3-4. 211603000 3-27 Invertebrate and fish species inhabiting the reef areas are similar to those found at the other receiver beach sites. Marine Mammals The Torrey Pines receiver beaches are utilized by the same species of marine mammals as the other receiver sites. Birds The presence or absence of both sensitive and nonsensitive bird species and the potential for these species to utilize the Torrey Pines receiver beaches are similar to other receiver beaches. 3.4.6 Buccaneer Beach/South Carlsbad Alternative Onshore placement of sand at alternative beach sites (Buccaneer Beach/South Carlsbad) is proposed as an alternative to onshore placement at Encinitas. The habitats and biological resources found at the alternate receiver beaches are similar to the other receiver sites. Sand Habitat The intertidal and shallow subtidal zones of these alternative receiver beaches are predominately sand habitat. The algae, invertebrate, and fish species that inhabit the sandy areas of these beaches are similar to those found at the other receiver beaches. Reef Habitat Buccaneer Beach receiver beach is devoid of reefs. Consequently, no sensitive marine resources exist at this site (Figure 3-1). The alternative South Carlsbad site has one small area of high relief reef surrounded by sand. This reef is vegetated with feather boa kelp and sea palms (Figure 3-2). Giant kelp is not present at either of these sites. 3-28 211603000 I I Feather Boa Kelp and Surfgrass Feather Boa Kelp Feather Boa Kelp LEGEND SAND LOW RELIEF SCATTERED REEF HIGH RELIEF REEF Scattered Feather Boa Kelp, Sea Palms,Dense SurfgrassCOBBLE/SAND Historical MaximumKelp Bed Canopies1978 to 1996 Feather Boa KelpKelp Bed Canopy1997 Mono Buoy Offshore Restricted Zone Fill Area Sinker Line Railroad DenseSurfgrass F I G U R E Torrey Pines Biological Resources /rotofcM(h/|iloli/fitunt/luMI>Unil Invertebrate and fish species inhabiting the reef at the alternative South Carlsbad site are similar to those found at the other receiver beach sites. Marine Mammals The Buccaneer Beach/South Carlsbad receiver beaches are utilized by the same species of marine mammals as the other receiver sites. Birds The presence or absence of both sensitive and nonsensitive bird species and the potential for these species to utilize the Buccaneer Beach/South Carlsbad receiver beaches are similar to other receiver beaches. 3.5 LAND USE AND RECREATION 3.5.1 Definition of Resource Land use comprises natural conditions or human-modified activities occurring at a particular location. Human-modified land use categories include residential, commercial, industrial, transportation, communications and utilities, agriculture, institutional, recreational, and other developed use areas. Management plans and zoning regulations determine the type and extent of land use allowable in specific areas and are typically intended to protect specifically designated or environmentally sensitive areas. Recreational resources represent a significant element for beach areas and often provide a variety of recreational opportunities. These include surfing, sunbathing, swimming, diving, hiking, etc. The proposed beach replenishment areas are located in northern San Diego County along the Pacific Ocean, within the jurisdictions of the cities of Carlsbad, Encinitas, and San Diego, and the California State Department of Parks and Recreation. The alternative receiver site at Buccaneer Beach is under the jurisdiction of the City of Oceanside. Regional access is provided by 1-5 to the east, State Route (SR)-52 to the south, and SR-78 to the north. The coastal area of northern San Diego County is generally 211603000 3-31 characterized as suburban residential interspersed with commercial uses. Recreational opportunities along the coast consist of a variety of activities. One of the more popular recreational activities is surfing. Figure 3-5 illustrates popular surf breaks from Oceanside to Torrey Pines. 3.5.2 North Carlsbad The North Carlsbad receiver beach is located within the jurisdiction of the City of Carlsbad. The site is moderately utilized for beach activities due to its confined location between Buena Vista Lagoon and Carlsbad State Beach. Access to the site is via public accessways from Ocean Street. The area located adjacent to the proposed beach receiver site is comprised of new and older residential uses and a military (Army/Navy) preparatory school. Buena Vista Lagoon is located to the north of the proposed beach replenishment footprint. Recreational activities on the site include swimming, sport fishing, surfing, sailing, picnicking, and hiking. Beach surf breaks are scattered along the shore near the proposed beach receiver site; however, no nearshore reefs supporting surf breaks are located in the vicinity. Surfing conditions in this area are primarily dependent upon shifting formations of nearshore sandbars. Most ocean-related recreational activities that occur at the beaches or in nearshore areas are available year-round due to the mild climate. The site is located within the Coastal Zone as designated in the City of Carlsbad General Plan (1994). The objective of the Coastal Zone is to identify areas subject to the requirements of the California Coastal Act of 1976. Any project within the Coastal Zone is subject to review by the City of Carlsbad and California Coastal Commission. In compliance with the California Coastal Act of 1976, the City certified a Local Coastal Program (LCP) in 1980. Subsequent amendments to the LCP in 1982, 1985, and 1988 have produced a substantive LCP, comprised of six segments. The proposed North Carlsbad receiver beach is located within the Mello II Segment (City of Carlsbad LCP 1996). In general, the LCP requires that development not impact biological or cultural resources, interfere with the public access to and along the shoreline, or impact visual or natural resources in the Coastal Zone. The following policies identified in the City of Carlsbad Land Use Element of the General Plan, Chapter III: Environmental, Section C, are relevant to the proposed action: 3-32 211603000 Oceamideji Oceanside Pier Buccaneer Beach Alternative Fill Site North Carlsbadnil Site 3800 FEET SOURCE: Brim Gates & Pipes Terra Mar South Carlsbad Alternative Fill Site South Carlsbadnil Site Ponto Turtles 85/«Ts Tippers Cardiff Reef George's Tomato Patch Grandview Beacon's Stonesteps Moonlight D Street- GT's G Street Pacific Ocean Tree's Boneyards Swami's Dabbers- Pipes Traps Seaside Reef Palisades Table Tops Pill Box Cherry Hffl River Mouth Beach Break 8th Street South Del Mar Torrey Pines nil Site F I G U R E Recreational Surfing Sites 3-5 C.9. Implement to the greatest extent feasible the natural resource protection policies of the Local Coastal Program. C.ll. Participate in programs that restore and enhance the City's degraded natural resources. The following policy identified in the City of Carlsbad LCP5 Chapter II-2, Policy 4-1: Coastal Erosion, is also relevant to the proposed action: b. Beach Sand Erosion. Pursue mitigation measures -which address the causes of beach sand erosion; sand dredging ... is one such method -which has been suggested. The City should continue to participate in the Regional Coastal Erosion Committee's studies of the causes and cures for shoreline erosion. 3.53 South Carlsbad The proposed South Carlsbad receiver beach is located within the jurisdiction of the City of Carlsbad and the California State Department of Parks and Recreation, located approximately 1,100 m (3,600 ft) north of the Batiquitos Lagoon inlet. Due to its location on a State Beach adjacent to the South Carlsbad State Beach Campground, the receiver site is highly utilized for recreational purposes. The campground consists of 226 campsites, a lifeguard tower, park ranger facilities, and maintenance facilities. Beach surf breaks are scattered along the shore in the vicinity of the receiver site; however, no nearshore reefs supporting surf breaks are located in the immediate vicinity of the South Carlsbad receiver site. Surfing conditions in this area are primarily dependent upon shifting formations of nearshore sandbars. The site is located within the Coastal Zone as designated in the City of Carlsbad General Plan (1994). For relevant plans and policies under the City's Land Use Element and LCP, refer to Section 3.5.1. The receiver site is also subject to the plans and policies identified in the San Diego Coastal State Park System General Plan, Volume 3: South Carlsbad State Beach (1984). 3-34 211603000 This plan identifies proposed improvements to South Carlsbad State Beach facilities and policies intended to protect natural resources hi the vicinity of the State Beach. The following policy identified in the San Diego Coastal State Park System General Plan, Volume 3 is relevant to the proposed action: Littoral sand loss is recognized as a major threat to existing facilities and recreational resources. The department shall -work with other agencies, including the California Department of Boating and Waterways, the City of Carlsbad, the San Diego Association of Governments, and the U.S. Army Corps of Engineers, to develop regional solutions to the sand loss problem. Any major program of sand replenishment or retention must consider the regional nature of the problem and the regional impact of actions taken along a segment of the shoreline. 3.5.4 Encinitas The proposed Encinitas receiver beach is located within the jurisdiction of the City of Encinitas and is located approximately 70 m (230 ft) south of the Batiquitos Lagoon inlet. Due to erosion at the beach receiver site, it is only moderately used for recreational purposes. In addition, public access to this segment of beach is limited due to steep cliffs abutting the beach. Public stairways exist at Grandview Street and South El Portal Street, and several private stairways serve existing residences on the bluff. Several popular surf breaks exist along the shore in the vicinity of the receiver site, including "Tomato Patch," "Grandview," "Beacon's," and "Stone Steps." All surf breaks from "Tomato Patch" south to D Street are known as beach breaks (refer to Figure 3-5); however, scattered rocky reefs in the surf zone have an influence on breaking waves forming peaks along this beach segment. Popular surf breaks along this stretch are primarily a result of beach access points (due to the difficulty of access along this segment as a result of steep coastal cliffs). Moving south from G Street (refer to Figure 3-5), the surf breaks are more heavily influenced by reefs. Wave peaks are formed from reefs located within the surf zone. "Boneyards" and "Swami's" are definite examples of reef surf breaks south of the Encinitas receiver site. 211603000 3-35 The site is located within the Coastal Zone as designated in the City of Encinitas General Plan (1989). Any project within the Coastal Zone is subject to review by the City of Encinitas and California Coastal Commission. In compliance with the California Coastal Act of 1976, the City of Encinitas includes an LCP Land Use Plan (LUP) in their General Plan. The LUP identifies policies and provisions that serve to apply the Coastal Act hi the City. The Encinitas General Plan identifies issues and opportunities relative to planning decisions within the City. Regarding beaches, the plan states, "the beach areas are losing sand depth each year and sand replenishment programs are needed to provide for their restoration." Additionally, the Resource Management Element of the General Plan identifies the following policy relevant to the proposed action: 8.6 The City will encourage measures which would replenish sandy beaches in order to protect coastal bluffs from wave action and maintain beach recreational resources. The City shall consider the needs of surf-related recreational activities prior to implementation of such measures. 3.5.5 Torrey Pines The proposed Torrey Pines receiver sites are located within the jurisdiction of the cities of Del Mar and San Diego, and the California State Department of Parks and Recreation. Vicinity land use includes open space, single-family, and multi-family residential uses. Public access is via trails at Torrey Pines State Beach/State Reserve and South Camino Del Mar. Popular reef surf breaks identified in the vicinity of the Torrey Pines site are "8th Street" and "South Del Mar," located north of the proposed receiver site (refer to Figure 3-5). Scattered beach surf breaks also exist along the shore in front of the receiver site. The proposed Torrey Pines receiver sites are located within the Coastal Zone as designated hi the City of San Diego General Plan (1989) (southern site) and the City of Del Mar Land Use Element (1985) (northern site). Both of these cities have LCPs, which guide development in sensitive coastal areas and provide for the preservation of natural 3-36 211603000 resources. The LCPs require any project occurring within the Coastal Zone to be reviewed by the city and the California Coastal Commission. The receiver sites are also subject to the plans and policies identified in the San Diego Coastal State Park System General Plan, Volume 8: Torrey Pines State Beach and State Reserve (1984). This plan identifies proposed improvements to facilities at Torrey Pines State Beach and policies intended to protect natural resources in the vicinity of the State Beach. The following policy identified in the San Diego Coastal State Park System General Plan, Volume 8 is relevant to the proposed action: Sand and similar sediment in active alluvial fans and other storage areas in the Los Penasquitos -watershed is a valuable resource that shall be considered for replenishment of littoral beach sand. Material excavated from sediment basins and other depositional storage areas in the -watershed, and which is of suitable quantity, size, and chemical constituency to meet the management objectives of the state beach and state reserve, shall be considered for disposal into the littoral zone just below the Los Penasquitos Lagoon opening. When beach replenishment is not needed or appropriate at the time of necessary dredging, the sand should be deposited for eventual use as beach replenishment, provided that suitable locations for deposit are available and that steps are taken at them to protect significant natural resources and their public use. 3.5.6 Buccaneer Beach/South Carlsbad Alternative The proposed Buccaneer Beach alternative receiver site is located within the jurisdiction of the City of Oceanside. The area adjacent to the proposed receiver site is comprised of new and older residential uses. Loma Alta Creek is located directly north and Buena Vista Lagoon is located directly south of the replenishment footprint. Erosion has affected the existing beach in this area; therefore, recreational activities are primarily limited to periods of low tide. Scattered beach surf breaks occur at various locations along the receiver site; however, no nearshore reefs supporting surf breaks are located in the vicinity of the Buccaneer Beach alternative site. 211603000 3-37 The site is located within the Coastal Zone as designated in the City of Oceanside Land Use Element (1989). The objective of the coastal zone is to "provide for the conservation of the City's coastal resources and fulfill the requirements of the California Coastal Act of 1976." In compliance with the California Coastal Act of 1976, the City adopted an LCP in 1985. In general, the City of Oceanside LCP requires that development not interfere with the public access to and along the shoreline. As stated in Policy A of Section 1.32 of the Land Use Element, The City shall utilize the certified Local Coastal Plan and supporting documentation for review of all proposed projects -within the Coastal Zone. Specifically, the goals and policies of the Local Coastal Program Land Use plan shall be the guiding policy review document. The following policies identified in the Land Use Element, Section 3.17 Coastal Preservation, are relevant to the proposed action: A. The City shall attempt to preserve shoreline beach area as a valuable recreational asset and visitor inducement. B. The City shall continue with periodic replenishment of beach sand by the Federal government until permanent beach sand management systems are decided on and implemented. Information relative to the additional fill area alternative at the South Carlsbad receiver site is included in Section 3.5.3. 3.6 SAFETY AND ENVIRONMENTAL HEALTH 3.6.1 Definition of Resource For the purposes of this EA, safety issues are defined as those that directly affect the continued ability to protect and preserve life and property at locations along the proposed beach receiver sites. 3-38 211603000 Extensive sediment characterization analyses were conducted for the proposed receiver beaches as part of the Homeporting EIS. These analyses were conducted in accordance with ACOE, EPA, and Regional Water Quality Control Board (RWQCB) procedures for dredged sediment. Based on sediment studies, it was determined that the dredged material from San Diego Bay is suitable for beach replenishment and does not pose a threat to human health or the environment. Furthermore, approximately 5.4 million m3 (7.0 million cy) of dredged material is considered suitable for beach replenishment, of which approximately 2.2 million m3 (2.9 million cy) would be used as beach replenishment at the four proposed receiver beaches. 3.6.2 North Carlsbad The California State Department of Parks and Recreation provides lifeguard services in the vicinity of the North Carlsbad receiver beach. The lifeguards are responsible for all recreational safety measures along the beaches. Safety measures include manned lifeguard towers and regular vehicle patrols during the summer months. 3.63 South Carlsbad The California State Department of Parks and Recreation provides lifeguard services in the vicinity of the South Carlsbad receiver beach. Safety measures include manned lifeguard towers and regular vehicle patrols during the summer months. Lifeguard towers are more heavily staffed on weekends during the summer. 3.6.4 Encinitas The City of Encinitas provides lifeguard services in the vicinity of the Encinitas receiver beach. Safety measures include manned lifeguard towers and regular vehicle patrols during the summer months and intermittent vehicle patrols throughout the year. Lifeguard towers are only staffed during summer months. 3.6.5 Torrey Pines The California State Department of Parks and Recreation provides lifeguard services at Torrey Pines State Beach in the vicinity of the receiver beach. Safety measures include 211603000 3-39 manned lifeguard towers and regular vehicle patrols on weekends during the summer months. Vehicle patrols are provided on weekdays during the summer. 3.6.6 Buccaneer Beach/South Carlsbad Alternative The City of Oceanside provides lifeguard services in the vicinity of the proposed Buccaneer Beach alternative receiver beach. Safety measures include regular vehicle patrols during the summer months. The beach area added to the South Carlsbad receiver site under the alternative plan would be under the jurisdiction of the California State Department of Parks and Recreation. Refer to Section 3.6.3 for lifeguard services in this area. 3.7 AESTHETICS 3.7.1 Definition of Resource Aesthetic resources comprise natural and manufactured features that give a particular area its visual qualities. These features form the overall impression that an observer receives of an area, or its landscape character. Landforms, water surfaces, vegetation, and manufactured features are considered characteristic of an area if they are inherent to the structure and function of its landscape. The significance of a change hi visual character is influenced by social considerations, including public value placed on the resource, public awareness, and general community concern for visual resources in the area. These social considerations are addressed as visual sensitivity and are defined as the degree of public interest hi a visual resource and concern over adverse changes hi the quality of that resource. High visual sensitivity exists when the public can be expected to react strongly to a potential change hi visual quality. Moderate visual sensitivity would exist when affected views are secondary in importance or are similar to others hi the region. Low visual sensitivity exists when the public has little or no concern about changes hi the landscape. 3.7.2 North Carlsbad Primary views of the proposed North Carlsbad receiver beach are from beach-front residences, which run the length of the proposed receiver site. The North Carlsbad 3-40 211603000 receiver site is also visible from Buena Vista Lagoon, areas with beach access on Ocean Street, and Carlsbad Boulevard (south of Pine Avenue). Visual resources at the North Carlsbad receiver site consist of a flat sandy beach lying in front of rip-rap slopes and sea walls that support beach-front structures. Slopes behind rip-rap and sea wall structures rise to a height of approximately 10 m (30 ft). Structures along the receiver segment include single-family residences, apartments, condominiums, and a military preparatory school. The sand beach along this segment is typically under water during high tide (Figure 3-6). 3.73 South Carlsbad The proposed South Carlsbad receiver beach is visible from South Carlsbad State Beach Campground, parking areas north of the campground, and Carlsbad Boulevard. This receiver beach is characterized by a sand and cobble beach abutted by steep bluff slopes. Virtually no development exists along this stretch of beach with the exception of the State Beach Campground located on the bluff approximately 20 m (65 ft) above the beach. Several stairways run from the campground down onto the beach (Figure 3-7). 3.7.4 Encinitas The proposed Encinitas receiver beach sits below steep cliffs and is visible from Highway 101 (at Batiquitos Lagoon), several residences along the bluff, and Moonlight State Beach. It consists of very little existing beach area. Development along this beach segment includes single-family residences, apartments, and condominiums, which are located approximately 25 to 30 m (80 to 100 ft) above the beach on the bluff. Views of the beach along this stretch are dependent upon the tides. At high tide, the beach is not visible along the majority of the receiver area, as waves crash directly against the cliffs. At low tide, a low profile sand and cobble beach is visible below the cliffs. Several stairways descend onto the beach from residences located on the bluff (Figure 3-8). 3.7.5 Torrey Pines The proposed Torrey Pines receiver beach consists of two receiver sites; however, both sites are located on Torrey Pines State Beach. 211603000 3-41 a. View looking south from Buena Vista Lagoon outlet. I I I I I I b. View looking north from Oak Avenue. I I I I I I North Carlsbad Receiver Site Existing Views FIGURE 3-6 E:\ENVIR ASS'MT (ENV)\Environ AssessmenttCentre City DevelopmenftNth Carlsbad Views 1 .Fh5 c. View looking south from Palomar Airport Road. ... S:SK. ,,111 d. View looking north from maintenance area south of State Beach Campground. FIGURE South Carlsbad Receiver Site Existing Views 3-7 E:\ENVIR ASS'MT (ENV)\Environ AssessmenttCentre City DevelopmenftNth Carlsbad Views 2.Fh5 JSSgSS3888SSgg|ffigS e. View looking south from Batiquitos Lagoon inlet. Bjlllliil f. View looking north from Moonlight State Beach FIGURE Encinitas Receiver Site Existing Views 3-8 BENVIR ASSW(ENV)\Environ AssessmenftReceiver Beach EA\Encinrtas Receievr Site Photos The northern receiver beach consists of a fairly large low profile sandy beach abutted by steep slopes. This receiver site is visible from the Amtrak/Coaster railroad tracks, several residences along the bluff, and sections of South Camino Del Mar. The Amtrak/Coaster railroad tracks are located on the bluff approximately 12m (40 ft), directly above the beach. Several residences are located 5 to 10 m (15 to 30 ft) upslope of the railroad tracks (Figure 3-9). The southern Torrey Pines receiver site is visible from North Torrey Pines Road, the parking area at Torrey Pines State Reserve, and view points within the State Reserve. This segment consists of a thin sand and cobble beach abutted by steep cliffs. The majority of the beach is visible only during low tide, as waves reach the base of the cliffs at high tide. Cliffs range in elevation from approximately 15 to 60 m (50 to 200 ft). The beach trail from the State Reserve descends onto the beach, south of the receiver area. With the exception of the parking area for the State Reserve, no development exists in the vicinity of this beach segment (Figure 3-10). 3.7.6 Buccaneer Beach/South Carlsbad Alternative The proposed Buccaneer Beach alternative receiver site is visible from beach-front residences along the entire segment and beach access areas on South Pacific Street. Buccaneer Beach, directly south of Loma Alta Creek, consists of a sandy beach abutted by rip-rap slopes. Rip-rap and sea walls extend the length of the alternative receiver site to protect existing structures from high seas. The southern end of the alternative receiver site, located directly north of Buena Vista Lagoon, consists of a private development known as Saint Malo Beach. Little existing beach area remains along this segment (Figure 3-11). The alternative extension to the South Carlsbad receiver area consists of a sandy beach with scattered cobbles abutted by steep slopes. High scarps (approximately 3 m [10 ft]) are located between the high tide mark and existing slopes. This segment is visible from the northern portion of the State Campground, the parking area north of the campground, and Carlsbad Boulevard. 211603000 3-45 &; : g. View looking south from 4th street. I I I I I I I h. View looking north from Los Penasqurtos Lagoon outlet. North Torrey Pines Receiver Site Existing Views FIGURE 3-9 E:\ENVIR ASS'MT (ENV)\Environ AssessmenftCentre City DevelopmenftNth Carlsbad Views 3.FH5 I I I i. View looking south from Torrey Pines State Beach parking area. j. View looking north from end of Beach Trail. Southern Torrey Pines Receiver Site Existing Views FIGURE 3-10 WIR ASS'MT (ENV)\Environ AssessmenftCentre City DevelopmenttNth Carlsbad Views 4.Fh5 •:::::;::iiis&v k. View looking south from Loma Alta Creek. I. View looking north from Buena Vista Lagoon outlet. Buccaneer Beach Alternative Receiver Site Existing Views FIGURE 3-11 E:\ENVIR ASSMT (ENV)\Environ AssessmenftCentre City DevelopmenftNth Carlsbad Views 5.Fh5 3.8 STRUCTURES AND UTILITIES 3.8.1 Definition of Resource For the purpose of this EA, structures and utilities are defined as sewer outfalls, access stairs and ramps, storm drain pipes, seawalls, and lifeguard towers. The following section identifies the location of the existing structures and utilities within or adjacent to the beach receiver sites. To determine existing conditions for structures and utilities, a limited field survey was conducted and a field survey report was prepared by FRH. In addition, city engineering personnel were contacted to determine the location of city sewer and storm drain ocean outfalls and any other related facilities that could be potentially impacted by implementation of the proposed action. 3.8.2 North Carlsbad Several structures and utilities currently exist within the shoreline area of the proposed North Carlsbad beach receiver site. Each structure and utility is described below, and locations are depicted in Figure 3-12. 3.8.2.1 Access Stairs Public access stairs are located off of Ocean Street. In addition, several residential properties have private stairways for beach access, a few of which reach the beach surface. All other stairways in the vicinity of the proposed receiver site end approximately 1 m (3 ft) above the beach surface. 3.8.2.2 Storm Drains A 46-centimeter (cm) wide by 15 cm high (18 in by 6 in) rectangular concrete drainage outlet structure is located adjacent to the bottom of the public access stairs off Ocean Street. The top of the structure lies approximately 46 cm (18 in) above the beach surface. The concrete drainage structure contains two 10-cm-dia (4-in-dia) storm drain outlets, which extend approximately 1.2 m (4 ft) above the existing beach surface at the base of the stairs. 211603000 3-49 Bueng Vtata LoiInlet/Outlet Exlitlng Structure* and Utllty Impooti - North Corlebad Structure Buwia Vltto Lagoon Weir PuWlc Stair* from Ocean Av*. Stormdrolne Low eeawoll O Ocean Av*. SMWotl SeaWall Terraced SeoWall • " Steps Ground eovw Private St«pt (sJ^to 1) 68, 72 72 74 73,74 73.73A.74 73,75,78 76 77,78 76,77 Outltt Jnvwrt.Approx. a (m, MSL) Top 1.5m 2.6m T -fottorn ofStolg/RamDApprox. B. (m, Us.) Z8rn 2.0m 1.3m to 4.5m Comment* maintain lnl«t/outlit flow no advert* Impact Top of h<odwall»3.5m; Keep drain path dear Top woll-3.4m - no adverM Impact Bat* *l*v. • 4.1m; Top <l*v. • 4.6m - no adv*r»* Impact SeaWall Terraced SeoWoll Slept Ground cover Private .Stepe FIGURE Existing Structures and Utilities, North Carlsbad Site 3-12 BENVIR ASS'MT(ENV)\Envlron AssessmenftRecelver Beach EA\RB-Form«t.FH5 3.8.23 Sea Walls Several properties in the vicinity of the proposed North Carlsbad beach receiver site have sea walls to protect against erosion, a few of which are terraced sea walls. In addition, landscaping exists within the boundaries of the proposed beach receiver sites. 3.8.3 South Carlsbad Structures hi the vicinity of the proposed South Carlsbad beach receiver site include public access stairs and lifeguard towers. The structures are described below, and locations are depicted in Figure 3-13. 3.8.3.1 Access Stairs Four sets of public access stairways are located in the vicinity of the proposed receiver beach. All stairways have beach access from the State Park on top of the bluff. Base elevations of the stairways range from 1.5 m to 2.6 m (5 ft to 9 ft). In addition, five lifeguard towers are located along the beach with base elevations ranging from 1.7 m to 3.6m (6 ft to 12 ft). 3.8.4 Encinitas Several structures and utilities currently exist within the shoreline area of the proposed Encinitas receiver beach. Each structure and utility is described below, and locations are depicted in Figure 3-14. 3.8.4.1 Access Stairs Public and private stairways are located along the proposed receiver beach. Public stairways are located at Grandview Street and South El Portal Street. Several private stairways lead from residences on the bluff onto the proposed receiver beach. The base elevation of the stairways ranges from 0.5 to 3.5 m (1.6 to 11.5 ft). 211603000 3-51 ' *• *f-.> -_.^~—-^ 89 Stolre |3 Llfeguord Tower ato Stolre |4 Existing Structure* and Utllty Impacte - South Oceanelde Structure Stotre fl Stair* |2 Stolre |3 Lifeguard Tower fl Lifeguard Tower §2 Lifeguard Tower |3 • Lifeguard Tower §4 . . . : Lifeguard Tower #3 • Stairs |4 Dirt Road Lifeguard Tower 08 (*.% 1) 98, 99 Outlet InvertAppro*. 0. (m. Ma)Bottom ofStolre/ romDApprax. 0. m. MSI) 2.5m 2.6m 1.0m 2.5m • Boee 3.6m O Bate 5.0m O Bate 1.8m O Baee 1.7m O Baee 2.3m 2.3m O end 2.5m O Baee Commente 550m S/0 Enclnae Ch, — no adverse frnpact 25m S/0 Lifeguard Tower |3 - no adveree Impact • Potneettla (T)pleal for all etalre) - no adveree Impact 25m N/0 above etelre — no adveree Impact 275m S/0 Lifeguard Tower fl - no odveree Impact 250m S/0 Lifeguard Tower |2 - no adveree Impact 425m N/0 Pokiiettto etalre - no adveree Impact 175m N/0 Polniettlo etalre - no adveree Impact 288m N/0 Polntettla etalre - no adveree Impact Maintenance Road - no adveree Impact 105m S/0 End Dirt Road - no advene Impact FIGURE Existing Structures and Utilities, South Carlsbad Site 3-13 BENVIR ASS'MT(ENV)\Envlron AssessmenftRecelver Beach EA\HB-Format.FH5 I BAT1QUITOS LAGOON LH=P — ^ u i Existing Strueturm and Utility Impact* - Enckiltoi Structure Public Stoto O B Portal Stair* -Public and Prlvat* Seawall* Stomtdratn cutlet* (S*.^?. 1) 122 Outlet Invertftppran a (m, MS.) 1.Sm Jottom ofStolrj/HornD*pprcx. 0. (m, MSt) 0.5m O.Sm to 3.8m Om to 2m Comment*. no adveri* Impact no advw** Impact Baee of wall - no adver** Impact. 4-1S2om dla. and 1-91 cm dto. RCP'e - no adver** Impact FIGURE Existing Structures and Utilities, Enclnitas Site 3-14 3.8.4.2 Storm Drains One 91-cm-dia (36-in-dia) and four 152-cm-dia (60-in-dia) stonn drain pipes are located at the end of B Street at Moonlight State Beach. The City of Encinitas has excavated several meters around the outlets to expose the pipes and allow proper drainage flow. 3.8.4.3 Seawalls Several sea walls are located along the proposed receiver beach. The lowest exposed portion of the sea walls along this segment range from 0 to 2 m (0 to 6.6 ft). 3.8.5 Torrey Pines No structures or utilities presently exist within the shoreline area of the proposed Torrey Pines receiver beach. 3.8.6 Buccaneer Beach/South Carlsbad Alternative No utilities are located along the shoreline area of the Buccaneer Beach alternative receiver area. Structures in this area include public access stairs, which are depicted on Figure 3-15. No structures or utilities are identified in the shoreline area of the proposed extension to the South Carlsbad receiver site. 3.8.6.1 Access Stairs Public access stairs exist at Whaley Street along the Buccaneer Beach alternative segment. The bottom elevation of the stairway is approximately 2.0 m (6.6 ft) above MSL. 3-54 211603000 BUENA VISTA LAGOON Existing Structures ond Utility Impact* - Buccaneer Beach Structure Stair* O Whaley St (SeMe 1) 87 Outlet InvertApprex. D. (m, NSl) — Bottom ofStolre/RampAppro* o'fm, OS.) 1.8+ Commente Minor Impact - bottom portion will be covered with eond. FIGURE Existing Structures and Utilities, Buccaneer Beach Alternative Site BENVIR ASS'MT(ENV)\Envlron Assessmenl\Recelver Beach EA\RB-Format.FH5 3-15 3.9 NOISE 3.9.1 Definition of Resource Noise is defined as unwanted sound or, more specifically, as any sound that is undesirable because it interferes with communication, is intense enough to damage hearing, or is otherwise annoying. Human response to noise can vary according to the type and characteristics of the noise source, the distance between the noise source and the receptor, the sensitivity of the receptor, and the time of day. Due to the wide range in sound levels, sound is expressed in decibels (dB), a unit of measure based on a logarithmic scale. A 10 dB increase in noise level corresponds to a 100 percent increase (or doubling) in perceived loudness. As a general rule, a 5 dB change is necessary for noise increases to be noticeable to the human ear. Sound measurement is further refined by using an A-weighted decibel scale that emphasizes the range of sound frequencies most audible to the human ear (between 1,000 and 8,000 cycles per second). Lj,, is a noise metric that averages A-weighted sound levels over a 24-hour period, with an additional 10 dB penalty added to noise events occurring between 10:00 p.m. and 7:00 a.m. This penalty is intended to compensate for generally lower background noise levels at night and the additional annoyance of night-time noise events. Current ambient acoustical conditions at the proposed receiver beaches are typical of that observed for nearshore beach communities. The areas are dominated by existing noise sources including ocean surf, recreational activities, and vehicle traffic on adjacent roads. 3.9.2 North Carlsbad 3.9.2.1 Noise Measurements To determine existing noise levels in the vicinity of the project site, a limited noise monitoring study was performed at the proposed replenishment site on April 16, 1997. Measurements were taken at the most accessible beach locations (i.e., direct beach access pouits). Ideally, meter placement corresponded to a position relatively close to existing receptors. When this condition was not possible, measurements were taken at the closest 3-56 211603000 available point. In all cases, three measurements per receiver site were taken, which corresponded to respectively (1) the northernmost end of the receiver area, (2) the midpoint of the project area, and (3) the southernmost end of the receiver area. Surf conditions during all tests were moderate with low surge and 2 to 4 ft waves at approximately 10-second intervals. A Larson Davis Model 700 ANSI Type 2 integrating sound level meter was used to collect the data. A series of short-term (15-minute) sound level measurements were taken to quantify the existing ambient conditions. This monitoring duration was deemed adequate since the background noise was of a steady-state nature. All measurements were taken in the morning between 8 a.m. and 12 p.m. The North Carlsbad area consists primarily of residential uses situated at an elevation of approximately +3 to +4.5 m (+10 to +15 ft) above MSL with approximately 10 to 15 m (30 to 50 ft) of setback from the boundary of the proposed construction operations. Current average ambient acoustical conditions are shown in Table 3-2. From the observed readings it is apparent that the site has a relatively high background level due to the constant surf activity. This is typical of a beach environment. Table 3-2 AMBIENT ACOUSTICAL CONDITIONS AT NORTH CARLSBAD Monitoring Point Leq-15 (dBA) Min(dBA) Max(dBA) (MP) NC-1 NC-2 NC-3 66.0 68.0 69.5 62.5 62.5 62.0 71.5 69.5 72.0 Measurements corresponded to (NC = North Carlsbad): • NC-1: The northernmost portion of the receiver area • NC-2: The midpoint of the receiver area • NC-3: The southernmost portion of the receiver area Measurements performed by Ogden on April 16,1997 In addition to the above point measurements, a 24-hour continuous monitoring test was performed adjacent to the beach to determine the temporal variation of the ambient sound 211603000 3-57 level as a function of time. For this effort, a fixed noise monitoring station was installed in the outside recreational area of the Army and Navy Academy located at 2605 Carlsbad Boulevard in the City of Carlsbad. The recreational area was abandoned during the test interval. Based on the field measurements (24 hours, 9 minutes of monitoring), the average sound level was 65.0 dBA Leq(24h). The maximum recorded sound level was 96.0 dBA while the minimum attainable level was 56.5 dBA. These levels describe the typical bounds of noise to be expected at any beach site under investigation. 3.9.2.2 Noise Ordinances The Carlsbad Municipal Code Section 8.48.010 describes specific noises prohibited within the City. The maximum permissible noise level limit is set at 75 dBA L^. The section of the City Code relevant to the proposed action is cited below: The erection, demolition, alteration, or repair of any building or structure or the grading or excavation of land in such a manner as to create disturbing, excessive, or offensive noise during the folio-wing hours, except as hereinafter provided, is a violation of this code: (1) After sunset on any day, and before seven a.m., Monday through Friday, and before eight a.m. on Saturday; (2) All day on Sunday, New Year's Day, Memorial Day, Independence Day, Labor Day, Veteran's Day, Thanksgiving Day and Christmas Day. 3.93 South Carlsbad 3.93.1 Noise Measurements Noise measurements were taken at South Carlsbad during the noise monitoring study conducted for this project on April 16, 1997 (see Section 3.9.2.1). Equipment and procedures were the same as those described for the North Carlsbad site. All measurements were taken in the afternoon between 1 p.m. and 5 p.m. 3-58 211603000 The South Carlsbad area consists of open space with recreational uses (i.e., camping areas at South Carlsbad State Beach) adjacent to the South Carlsbad replenishment area. These campsites are situated at an elevation of approximately +18 to +23 m (+60 to +75 ft) above MSL with approximately 15 m (50 ft) of setback from the boundary of the proposed construction operations. Current average ambient acoustical conditions at the South Carlsbad site are shown in Table 3-3. This type of acoustical response is typical of a beach environment. Table 3-3 AMBIENT ACOUSTICAL CONDITIONS AT SOUTH CARLSBAD Monitoring Point Leq-15 (dBA) Min(dBA) Max(dBA) (MP) SC-1 SC-2 SC-3 64.0 66.5 66.0 62.5 62.5 62.5 73.0 71.5 70.0 Measurements corresponded to (SC = South Carlsbad): • SC-1: The northernmost portion of the receiver area • SC-2: The midpoint of the receiver area • SC-3: The southernmost portion of the receiver area Measurements performed by Ogden on April 16, 1997 3.93.2 Noise Ordinances The area encompassed by the South Carlsbad site is under the jurisdiction of the State of California Department of Parks and Recreation. Although no formal noise standards exist for activities within state beaches, the California Department of Health Services (formerly known as the Office of Noise Control), has identified standards for noise levels based upon land use compatibility. These standards, known formally as the State of California Model Noise Ordinance, would serve as applicable guidelines for noise impact determination at state-operated campgrounds (Dupree 1997). Based upon these guidelines, campground areas at South Carlsbad would be classified as suburban single-family residential and have an hourly average noise threshold limit of 55 dBA between the hours of 7 a.m. and 10 p.m. and a level of 45 dBA between the hours 211603000 3-59 of 10 p.m. and 7 a.m. These noise limits are only guidelines for the determination of possible noise impacts. 3.9.4 Encinitas 3.9.4.1 Noise Measurements Noise measurements were taken at the Encinitas site during a noise monitoring study conducted for the Phase One Study (March 26, 1997). Equipment and procedures were the same as those described above for the North Carlsbad site. Land use at the Encinitas site consists of single- and multi-family dwellings located at the top of the adjacent sea cliff. These residences are situated at an elevation of approximately +18 to +27 m (+60 to +90 ft) above MSL with approximately 15 to 21 m (50 to 70 ft) of setback from the boundary of the proposed construction operations. Current average ambient acoustical conditions at the Encinitas site are shown in Table 3-4. The results are typical of a beach environment. Table 3-4 AMBIENT ACOUSTICAL CONDITIONS AT ENCINITAS Monitoring Point Leq-15 (dBA) Min(dBA) Max(dBA) (MP) E-l E-2 E-3 68.0 66.5 67.0 64.5 64.0 64.0 69.0 68.0 72.5 Measurements corresponded to (E = Encinitas): • E-1: The northernmost portion of the receiver area • E-2: The midpoint of the receiver area • E-3: The southernmost portion of the receiver area Measurements performed by Ogden on March 26,1997 3-60 211603000 3.9.4.2 Noise Ordinances City of Encinitas Construction noise within the City of Encinitas is governed by Performance Code Section 30.40.010. This section sets forth a list of performance standards dealing with any noise emissions affecting adjacent property. The sections of the City Code relevant to the proposed action are cited below: 1. Every use shall be so operated that the noise generated does not exceed the following levels at or beyond the lot line and does not exceed the limits of any adjacent zone {see below} 2. The interior noise level...must not exceed {a day-night average} of 45 dB. (It is assumed that the limit is set in A-weighted decibels). 3. It shall be unlawful for any person on any property within the City to create any noise, or to allow the creation of any noise on property owned, leased, occupied, or otherwise controlled by such person, which causes the noise level when measured on any other property to exceed the following: Adjacent Zone Residential Multifamily Residential Office/Commercial Light Industrial/Business Park One Hour Average Sound Level 7am- 10pm 10pm-7am 50 dB 45 dB 55 dB 50 dB 60 dB 55 dB 60 dB 55 dB Note: Even though dB is cited in the ordinance, it is understood that this is A-weighted decibels (ordBA) 211603000 3-61 a. The noise standard for cumulative period of more than 30 minutes in any hour; or, b. The noise standard plus 5 dB for a cumulative period of more than 15 minutes in any hour; or, c. The noise standard plus up to 15 dBfor a cumulative period of more than 1 minute in any hour; or, d. The noise standard plus 20 dBfor any period of time. 3.9.5 Torrey Pines/Del Mar 3.9.5.1 Noise Measurements Noise measurements were taken at Torrey Pines/Del Mar during the noise monitoring study conducted for this project on April 17, 1997. Equipment and procedures were the same as those described for the North Carlsbad site. All measurements were taken in the afternoon between 8 a.m. and 1 p.m. The Torrey Pines area consists primarily of residential uses along the northern portion of the project area (i.e., areas north of Penasquitos Lagoon entrance) and state park areas to the south. Residential uses within the northern portion are located within the City of Del Mar and are situated at an elevation of approximately +23 to +27 m (+75 to +90 ft) above MSL with approximately 30 to 60 m (100 to 200 ft) of setback from the boundary of the proposed construction operations. The actual construction activity, however, is taking place on State of California lands. Land uses along the southern portion of the project area consist of state lands known as the Torrey Pines Recreation Area/State Park. There are no affected structures within this area. Current average ambient acoustical conditions are shown in Table 3-5. From the observed readings it is apparent that the site has a relatively high background level due to the constant surf activity. This is typical of a beach environment. 3-62 211603000 Table 3-5 AMBIENT ACOUSTICAL CONDITIONS AT TORREY PINES/DEL MAR Monitoring Point , 15 (dBA) Min (dBA) Max (dBA) (MP) TP-1 TP-2 TP-3 64.5 64.5 61.5 61.5 61.0 59.0 71.0 78.0 72.0 Measurements corresponded to (TP = Torrey Pines): • TP-1: The northernmost portion of the receiver area • TP-2: The midpoint of the receiver area • TP-3: The southernmost portion of the receiver area Measurements performed by Ogden on April 17, 1997 3.9.5.2 Noise Ordinances Construction noise within the City of Del Mar (northern Torrey Pines Receiver Beach) is governed by Chapter 9.20.040 of the City of Del Mar Municipal Code. The section of the Noise Regulations which is relevant to the proposed action is cited below: Any person who operates powered construction equipment, erects, constructs, demolishes, excavates for, alters or repairs any building or structure within the City of Del Mar in such a manner as to cause noise to be received beyond the boundaries of the property on which the construction work is occurring shall comply with the following: A. No construction work shall be performed on Sundays, or City holidays, or before 9:00 a.m. or after 7:00p.m. on Saturday. B. No construction work shall be performed before 7:00 a.m. or after 7:00 p.m. C. Construction activity shall not cause an hourly average sound level greater than 75 decibels on property zoned or used for residential purposes. 211603000 3-63 D. Exception: A person may perform construction -work on the person's own property, provided such construction activity is not carried on for profit or livelihood, between the hours of10:00 a.m. and 5:00p.m. on Sundays and City holidays. Noise sensitive land uses within the southern Torrey Pines receiver area fall under the jurisdiction of the City of San Diego. Construction noise within the City is regulated by Noise Ordinance Section 36.410. This ordinance sets construction operations to occur between the hours of 7 a.m. and 7 p.m. Monday through Saturday. The maximum permissible level over any 8-hour interval between these times is 75 dBA L^. There are no noise sensitive receptors along the southern portion of the project area (i.e., areas under the jurisdiction of the City of San Diego). 3.9.6 Buccaneer Beach (City of Oceanside)/South Carlsbad Alternative 3.9.6.1 Noise Measurements Noise measurements were taken at the Buccaneer Beach/South Carlsbad Alternative during the noise monitoring study conducted for this project on April 16, 1997. Equipment and procedures were the same as those described for the North Carlsbad site. All measurements were taken in the afternoon between 8 a.m. and 12 p.m. All noise data relative to the South Carlsbad Alternative fill site is presented in Section 3.9.3. The Buccaneer Beach area consists primarily of residential uses situated at an elevation of approximately +3 to +4.5 m (+10 to +15 ft) above MSL with an approximate 10 to 15m (30 to 50 ft) of setback from the boundary of the proposed construction operations. Current average ambient acoustical conditions are shown in Table 3-6. These measured sound levels are typical of a beach environment. 3-64 211603000 Table 3-6 AMBIENT ACOUSTICAL CONDITIONS AT BUCCANEER BEACH Monitoring Point L . 5 (dBA) Min (<fflA) Max ((fflA) (MP) BB-1 BB-2 BB-3 65.5 64.5 66.0 61.5 62.5 61.0 79.0 72.5 69.0 Measurements corresponded to (BB = Buccaneer Beach): • BB-1: The northernmost portion of the receiver area • BB-2: The midpoint of the receiver area • BB-3: The southernmost portion of the receiver area Measurements performed by Ogden on April 16, 1997 3.9.6.2 Noise Ordinances Construction noise within the City of Oceanside is governed by Chapter 38 of the City of Oceanside Noise Ordinance. This section deals with specific prohibited noises. Subsection H deals with construction equipment of a pneumatic and diesel nature. Individual noise level limits would be identified hi the projects Conditional Use Permit, but admissible levels typically assigned by the City are 75 dBA Leq. The relevant part is cited below: Pile drivers, hammers, etc. The operation between the hours of 10:00p.m. and 7:00 a.m. of any pneumatic or air hammer, pile driver, steam shovel, derrick, steam, or electric hoist, parking lot cleaning equipment or another appliance, the use of which is attended by loud or unusual noise is prohibited. 211603000 3-65 This Page Intentionally Left Blank 3-66 211603000 SECTION 4 ENVIRONMENTAL CONSEQUENCES 4.1 GEOLOGY AND SOILS 4.1.1 Approach to Analysis The protection of unique geologic coastal features and the minimization of erosion are considered when evaluating potential impacts of a proposed action. For this analysis, an impact to geologic resources would be significant if it would (1) destroy, cover, or modify any unique geologic or physical features; (2) increase water erosion of soils, either on or offsite; (3) change the deposition or cause erosion of beach sand; (4) change the deposition or cause erosion that could modify a channel of a river or streambed, or an ocean, bay, inlet, or lake. Beach replenishment using dredged sediments is generally considered a beneficial use in areas where beach erosion is a problem, as fill can be utilized to create a sand berm that provides additional recreational uses and protects the shoreline. However, placement of the sand can also create a temporary change in the shoreline. Over a period of approximately 1 to 2 years, the sand would be moved and redistributed from the placement location along shore and cross shore through natural littoral transport. At that time, the shoreline would again reach an equilibrium position that would be similar to the existing beach configuration. The shoreline would temporarily widen at locations upcoast and downcoast of the beach fill site, until natural littoral transport redistributed the sand along the coast, as described below. The following analysis of coastal geology and littoral processes related to beach replenishment is based on Chapter 8 of the Beach Sand Transport and Sedimentation Report prepared by FRH (1997). Refer to Section 5 of this EA for cumulative impacts to geology and soils. 211603000 4-1 4.1.2 North Carlsbad 4.1.2.1 Coastal Geology The proposed action would place approximately 420,510 m3 (549,985 cy) of dredged sediment at the proposed receiver location in North Carlsbad. Sediment deposited on the beach would be spread along shore and cross shore through natural littoral transport. Shoreline positions were modeled based on the anticipated sediment movement and were predicted for periods of 3 months, 6 months, and 12 months after sand placement (Figure 4-1). Placement of sand on the beach at North Carlsbad would widen the existing beach area to the north and south subsequent to pumping operations. However, results of the modeling indicate that most of the beach fill would erode over a 1- to 2-year period, spreading longshore and cross shore. Longshore movement of sediment would generally be confined to 4,000 m (13,000 ft) upcoast and downcoast of the beach fill area. Cross shore movement would generally be confined to 350 m (1,150 ft) from the back of the existing beach area. Seasonal cross shore movement would transport the fill material offshore in the winter and back onto the beach in the summer, repeating this trend over subsequent seasons; however, seasonal loss due to natural littoral processes would occur (FRH 1997). Sediment would move to an offshore sandbar seasonally. Modeling indicates that the average maximum thickness of the sandbar would consist of 0.5 to 1.5 m (1.6 to 5.0 ft) in the summer and 1.5 to 2.0 m (5.0 to 6.6 ft) in the winter. Beach profile surveys taken from 1987 to 1996 show the formation of an offshore sandbar in North Carlsbad starting approximately 150 to 200 m (500 to 660 ft) offshore and extending an average distance of 100 m (330 ft) seaward (FRH 1997). Sediment movement subsequent to the proposed action would follow natural seasonal and littoral trends. A minor increase in average sand thickness would be anticipated, on the order of 0.3 m (1.0 ft) (FRH 1997). The increased thickness would be greatest in the vicinity of MSL and decrease seaward. The anticipated increase in sand thickness would be similar to that which normally occurs with seasonal sediment fluctuation. Therefore, significant impacts to coastal geology would not occur due to sediment transport or increased sediment thickness. 4-2 211603000 EOHgos.imSr . APPROXIMATE SHORELINE AT 12 MONTHS AFTER PLACEMENT o> I APPROXIMATE F*e SHORELINE POS -500 -550 -600 -650 -700 3500 4500 5500 6500 Shoreline Station (m) Shoreline position exagerated 5X 7500 8500 9500 Source: Frederic R. Harris, Inc., 1997 FIGURE Mean Sea Level Shoreline Response, North Carlsbad 4-1 E:\ENVIRONMENTAL\RECEIVER BEACHVCOREL FILES\RES-NCA.CDR 4.1.2.2 Littoral Processes Sediment placed onshore at North Carlsbad would be distributed along the coast by the Oceanside Littoral Cell processes. Net littoral transport in the area of the receiver beach is estimated to move south, with the capacity to move approximately 78,000m3 to 194,000 m3 (100,000 to 250,000 cy) per year. This downcoast movement is the net result of both upcoast and downcoast movements that occur depending on the angle of wave approach. Previous placement of fills on beaches in Oceanside and Carlsbad have not shown dramatic changes in the littoral process. Since 1955, over 10 million m3 (13 million cy) of fill have been placed onshore or nearshore in Oceanside by the ACOE with no adverse impacts having been recorded. Similarly, over 9 million m3 of fill have been placed onshore in Carlsbad as a result of maintenance dredging of Agua Hedionda Lagoon and enhancement of Batiquitos Lagoon. No adverse impacts to littoral transport have occurred. These past beach fills were in the same range as the proposed fill quantity. Therefore, based on past fill events, placement of sediment onshore at North Carlsbad would not change the littoral transport process. As discussed above, it is anticipated that the majority of beach fill would be transported into the shallow subtidal area within 2 years of replenishment operations. During this time, potential effects to wave activity in the vicinity of the receiver area could occur. According to the sand transport study prepared for this project (FRH 1997), however, minimal changes would occur to the beach profile due to the addition of sediment to the nearshore area. Accretion of sediment in the shallow subtidal zone would be anticipated to create sand bars, which would likely improve surf break conditions. Scarping could occur during time of high waves. This could cause minor changes in wave breaking characteristics and slightly increase wave energy reflection during times of low waves (approximately 1 m or less). However, this change would be negligible and would be considered insignificant. 4-4 211603000 4.1.3 South Carlsbad 4.1.3.1 Coastal Geology The proposed action would place approximately 420,510 m3 (549,985 cy) of dredged sediment at the receiver beach location in South Carlsbad. Sediment deposited on the beach would be spread along shore and cross shore through natural littoral transport. Shoreline positions were modeled based on the anticipated sediment movement and were predicted for periods of 3 months, 6 months, and 12 months after sand placement (Figure 4-2). Placement of sediment at the South Carlsbad site would widen the existing beach areas to the north and south subsequent to pumping operations. Similar to the North Carlsbad site, the majority of beach fill would erode over a 1- to 2-year period, spreading longshore and cross shore. Longshore movement of sediment would generally be confined to 6,000 m (19,700 ft) upcoast and downcoast of the beach fill area. Cross shore movement would generally be confined to within 400 m (1,300 ft) from the back of the existing beach (FRH 1997). Seasonal movement similar to that of the North Carlsbad site would occur. An offshore sandbar at the South Carlsbad fill site starts approximately 75 to 250 m (250 to 820 ft) offshore and extends an average distance of 100 m (330 ft) seaward. Subsequent to fill activities, the average maximum thickness of the sandbar would be 0.8 to 1.5 m (2.6 to 5.0 ft) in the summer and 1.2 to 2.3 m (4.0 to 7.5 ft) in the winter. A minor increase in sand thickness would be anticipated upon implementation of the proposed action, on the order of 0.2 m (0.6 ft). The increased thickness would be greatest in the vicinity of MSL and decrease seaward. The anticipated increase hi sediment thickness would be similar to that which normally occurs with seasonal sediment fluctuation. Therefore, significant impacts to coastal geology would not occur as a result of sediment transport or increased sediment thickness. 4.1.3.2 Littoral Processes Because littoral processes within the Oceanside Cell dominate a large region of the coast, changes to beaches in the vicinity of the South Carlsbad receiver site would be similar to 211603000 4-5 •Tin -BEACH FILL- - APPROXIMATE SHORELINE AT 12 MONTHS AFTER PLACEMENT Pre-RII3 months 6 months 12 months CO -700 500 1500 2500 3500 Shoreline Station (m) 4500 5500 Source: Frederic R. Harris, Inc., 1997 6500 Mean Sea Level Shoreline Response, South Carlsbad Site FIGURE 4-2 E:\ENVIRONMENTAL\RECEIVER BEACWCOREL FILES\RES-SCA3.DCR those affecting the North Carlsbad site. A sand berm would be expected to form in the shallow subtidal area as a result of sediment transported into this zone. Any changes to breaking waves resulting from the proposed action would be similar to those previously described for North Carlsbad. Significant impacts to littoral processes would not occur as a result of the proposed action. 4.1.4 Encinitas 4.1.4.1 Coastal Geology The proposed action would place approximately 871,620 m3 (114,000 cy) of dredged sediment at the receiver beach in Encinitas. Sediment deposited on the beach would be spread along shore and cross shore through natural littoral transport. Shoreline positions were modeled based on the anticipated sediment movement and were predicted for periods of 3 months, 6 months, and 12 months after sand placement (Figure 4-3). Placement of sediment at the Encinitas site would widen the existing beach areas to the north and south subsequent to pumping operations. Similar to the Carlsbad sites, most of the beach fill would erode over a 1- to 2-year period, spreading longshore and cross shore. Longshore movement of sediment would generally be confined to 9,000 m (29,500 ft) upcoast and downcoast of the beach fill area. Cross shore movement would generally be confined to within 450 m (1,500 ft) from the back of the existing beach (FRH 1997). Seasonal movement similar to that of the Carlsbad sites would occur. Beach profile surveys taken from 1983 through 1996 show the formation of an offshore sandbar at the Encinitas fill site starting at approximately 100 to 200 m (330 to 660 ft) offshore and extending an average distance of 120 m (400 ft) seaward. Subsequent to fill activities, the average maximum thickness of the sandbar would be 1.0 to 1.8 m (3.3 to 5.9 ft) in the summer and 1.8 to 2.4 m (5.9 to 7.9 ft) in the winter. Upon implementation of the proposed action, a minor increase in sand thickness would be anticipated, on the order of 0.2 m (0.6 ft). The increased thickness would be greatest in the vicinity of MSL and decrease seaward. The anticipated increase in sediment thickness would be similar to that which normally occurs with seasonal sediment fluctuation. However, intertidal and shallow subtidal reefs could potentially be covered 211603000 4-7 -100 g -1504) 1 I -200 -250 g -300 -350 -400 -APPROXIMATE SHORELINE AT 12 MONTHS AFTER PLACEMENT BEACH FILL - BATIQUITOS LAGOON JETTIES —— Pre-FIII 3 months 6 months12 months 5000 6000 7000 8000 Shoreline Station (m) 9000 10000 11000 Mean Sea Level Shoreline Response, Encinitas Site RENVIR ASS'MT(ENV)\Envlron Assessment\Recelver Beach EA\RB-Format.FH5 FIGURE 4-3 from the deposition of sediment in the substrate area at Encinitas. Refer to Section 4.4.3.1, Biology, for discussion of impacts to biological resources. Significant impacts to coastal geology would not occur due to sediment transport or increased sediment thickness. 4.1.4.2 Littoral Processes Because the littoral processes within the Oceanside Cell dominate a large region of the coast, any changes to beaches in the vicinity of the Encinitas receiver site would be similar to those affecting the Carlsbad sites. A sand berm would be expected to form in the shallow subtidal area as a result of sediment transported into this zone. Any changes to breaking waves resulting from the proposed action would be similar to those previously described for the Carlsbad receiver sites; no significant impacts to littoral processes would occur as a result of the proposed action. 4.1.5 Torrey Pines 4.1.5.1 Coastal Geology The proposed action would place approximately 496,970 m3 (614,670 cy) of dredged sediment at two areas within the Torrey Pines receiver site. Approximately 279,545 m3 (365,610 cy) would be placed along the northern portion of Torrey Pines State Beach and approximately 217,425 m3 (284,530 cy) would be placed along the southern portion of the State Beach adjacent to the State Reserve. Sediment deposited on the beaches would be spread along shore and cross shore through natural littoral transport. Shoreline positions were modeled based on the anticipated sediment movement and were predicted for periods of 3 months, 6 months, and 12 months after sand placement (Figure 4-4). Placement of sediment on beaches at the Torrey Pines site would widen the existing beach areas to the north and south subsequent to pumping operations. Similar to the other receiver sites, most of the beach fill would erode over a 1- to 2-year period, spreading longshore and cross shore. Longshore movement of sediment would generally be confined to 6,000 m (19,700 ft) upcoast and downcoast of the beach fill area. Cross shore movement would generally be confined to within 500 m (1,600 ft) from the back of 211603000 4-9 -100 -400 1000 SOUTH- BEACH FILL -APPROXIMATE SHORELINE AT 12 MONTHS AFTER PLACEMENT APPROXIMATE SHORELINE POS Pre-FIII3 months 6 months12 months 2000 3000 4000 Shoreline Station (m) 5000 6000 7000 Mean Sea Level Shoreline Response, Torrey Pines Site FIGURE 4-4 E\ENVIR ASS'MT(ENV)\Envlron Assessment\Recelver Beach EA\RB-Format.FH5 the existing beach (FRH 1997). Seasonal movement similar to that of the other receiver areas would occur. Beach profiles taken from 1983 through 1987 show the formation of an offshore sandbar along the Torrey Pines site, which spans both the northern and southern receiver locations. The bar is located approximately 120 to 200 m (400 to 660 ft) offshore and extends an average distance of 85 m (280 ft) seaward. Subsequent to fill activities, the average maximum thickness of the sandbar would be 0.7 to 1.4 m (2.3 to 4.6 ft) in the summer and 1.8 to 2.5 m (5.9 to 8.2 ft) hi the winter. A minor increase in sand thickness would be anticipated to occur upon implementation of the proposed action, on the order of 0.2 m (0.6 ft). The increased thickness would be greatest hi the vicinity of MSL and decrease seaward. The anticipated increase in sediment thickness would be similar to that which normally occurs with seasonal sediment fluctuation. Therefore, significant impacts to coastal geology would not occur due to sediment transport or increased sediment thickness. 4.1.5.2 Littoral Processes Littoral processes within the Oceanside Cell dominate a large region of the coast; thus, any changes to beaches in the vicinity of the Torrey Pines receiver site would be similar to those affecting the other receiver sites. A sand berm would be expected to form hi the shallow subtidal area as a result of sediment transported into this zone. Any changes to breaking waves resulting from the proposed action would be similar to those previously described for North Carlsbad; therefore, significant impacts to littoral processes would not occur as a result of the proposed action. 4.1.6 Buccaneer Beach/South Carlsbad Alternative 4.1.6.1 Coastal Geology As an alternative to the proposed Encinitas fill site, approximately 580,245 m3 (758,900 cy) of dredged sediment would be placed at the Buccaneer Beach alternative receiver site, and approximately 291,375 m3 (381,090 cy) of additional fill would be placed at the South Carlsbad receiver site. Sediment deposited on the beaches would be spread along shore and cross shore through natural littoral transport. Shoreline positions at Buccaneer 211603000 4-11 Beach were modeled based on the anticipated sediment movement and were predicted for periods of 3 months, 6 months, and 12 months after sand placement (Figure 4-5). Similarly, shoreline positions were modeled at South Carlsbad to reflect the additional fill under the alternative plan (Figure 4-6). Placement of sediment on the alternative beach sites would widen the existing beach areas to the north and south of the receiver locations subsequent to pumping operations. Similar to the proposed receiver sites, most of the beach fill would erode over a 1- to 2-year period, spreading longshore and cross shore. Longshore movement of sediment at Buccaneer Beach would generally be confined to 5,000 m (16,400 ft) upcoast and downcoast of the beach fill area. Cross shore movement would generally be confined to within 350 m (1,150 ft) from the back of the existing beach (FRH 1997). With the addition of fill at the South Carlsbad site, similar longshore and cross shore movement to that of the proposed action at South Carlsbad would occur (refer to Section 4.1.2.1). Seasonal movement similar to that of the other receiver areas would occur. The beach profile at Buccaneer Beach is similar to North Carlsbad, which is described in Section 4.1.1.1. An offshore sandbar is located approximately 150 to 200 m (500 to 660 ft) offshore and extends an average distance of 100 m (330 ft) seaward. Subsequent to fill activities, the average maximum thickness of the sandbar in this area would be 0.5 to 1.5 m (1.6 to 5.0 ft) in the summer and 1.5 to 2.0 m (5.0 to 6.6 ft) in the winter. The beach profile at South Carlsbad subsequent to the addition of fill alternative would be similar to that of the proposed action at South Carlsbad, as described in Section 4.1.3.1. A minor increase in sand thickness would be anticipated to occur at Buccaneer Beach, on the order of 0.3 m (1.0 ft). Additional fill placed at South Carlsbad would be expected to increase the sand thickness by 0.2 m (0.6 ft). The increased thickness at these locations would be greatest in the vicinity of MSL and decrease seaward. The anticipated increase in sediment thickness would be similar to that which normally occurs with seasonal sediment fluctuation. Therefore, significant impacts to coastal geology would not occur due to sediment transport or increased sediment thickness. 4.1.6.2 Littoral Processes Littoral processes within the Oceanside Cell dominate a large region of the coast; thus, any changes to beaches in the vicinity of the alternative sites would be similar to those 4-12 211603000 -100 S -150 o> I -200 (00 -250 £ -300 fc -350 ±J o>£ -400 2 P -450 •500 2000 CREEK -APPROXIMATE SHORELINE AT BEACH FILL- 12 MONTHS AFTER PLACEMENT APPROXIMATE P *E-I SHORELINE POS 3000 4000 5000 Shoreline Station (m) 6000 —— Pre-FIII 3 months 6 months 12 months 7000 8000 FIGURE Mean Sea Level Shoreline Response, Buccaneer Beach Alternative Site 4-5 BENVIR ASS'MT(ENV)\Envlron AssessmenftRecelver Beach EA\RB-Format.FH5 -BEACH FILL- - APPROXIMATE SHORELINE AT 12 MONTHS AFTER PLACEMENT <D 1 • §o> APPROXIMATE PRE-FILL—x SHORELINE POSITION BATIQUITOS Lft SOON \--12MONTHS Pre-Fill 3 months 6 months 12 months -400 -650 500 Source: Frederic R. Harris, Inc., 1997 1500 2500 3500 Shoreline Station (m) 4500 5500 6500 Mean Sea Level Shoreline Response, South Carlsbad Alternative Site FIGURE 4-6 E:\ENVIRONMENTAL\RECEIVER BEACHVCOREL FILESVRES-SCA.DCR affecting the proposed receiver sites. A sand berm would be expected to form in the shallow subtidal area as a result of sediment transported into this zone. Any changes to breaking waves resulting from the proposed action would be similar to those previously described for North Carlsbad; therefore, significant impacts to littoral processes would not occur as a result of the proposed action. 4.2 COASTAL WETLANDS 4.2.1 Approach to Analysis Impacts to coastal wetlands are based on studies performed as part of the Beach Sand Transport and Sedimentation Report (FRH 1997). Adverse impacts to coastal wetlands typically result if long-term closure of any lagoon, river, or creek occurs as a result of a proposed project. Long-term closure events are defined relative to each coastal wetland area (i.e., lagoon, river, or creek mouth). For example, "long-term" could mean closure for a number of days at a river mouth, while closure for several months could be typical at a lagoon mouth. Consequently, maintenance dredging operations are currently hi place at a number of coastal wetlands along the San Diego coast to ensure that long-term closures do not result. Therefore, a significant impact would occur if substantial sediment accretion directly resulting from the proposed action caused closure of any lagoon, river, or creek mouth without an identified maintenance dredging program. 4.2.2 North Carlsbad Coastal wetlands identified in the vicinity of the North Carlsbad receiver site include San Luis Rey River, Loma Alta Creek, Buena Vista Lagoon, and Agua Hedionda Lagoon. The extent of influence of the North Carlsbad beach fill would not be expected to reach the San Luis Rey River to the north, or Agua Hedionda Lagoon to the south. Vicinity "boundaries" are based on modeling (FRH 1997). Potential impacts to Loma Alta Creek and Buena Vista Lagoon are described below. 4.2.2.1 Loma Alta Creek The North Carlsbad receiver beach is located approximately 1.6 km (1 mi) south of the Loma Alta Creek ocean outlet. The existing berm elevation adjacent to the creek is +3.2 m (+10.5 ft) MSL at Buccaneer Beach and +2.3 m (+7.5 ft) MSL at the adjacent 211603000 4-15 residential property to the north. The creek maintains its flow through this berm with a creek bed elevation of approximately -0.6 to -0.8 m (-2.0 to -2.6 ft) MSL. The MSL beach width at the creek mouth would not be expected to increase as a result of the proposed action. The proposed North Carlsbad beach fill would not spread to the creek mouth beyond what naturally occurs. The proposed fills would not result in an adverse impact to Loma Alta Creek since the City of Oceanside currently constructs a sand berm in front of the creek to prevent flow between Memorial Day and Labor Day. During the wet season, the City of Oceanside excavates a temporary channel to facilitate stream flow to the ocean. Therefore, as the City would continue to ensure adequate discharge at the creek mouth, adverse impacts to Loma Alta Creek would not occur as a result of the proposed action. 4.2.2.2 Buena Vista Lagoon The north end of the proposed North Carlsbad receiver beach is located directly south of the Buena Vista Lagoon ocean outlet. Modeling results indicate that sediment from the North Carlsbad fill site would migrate to the vicinity of the Buena Vista Lagoon outlet within 12 months of fill placement. Approximately 19 m (62 ft) of shoreline accretion would be expected to occur hi front of the lagoon. The existing wen- at the lagoon is at an elevation of +1.82 m (+6.0 ft) MSL, and the fill berm design would be approximately +2.9 m (9.5 ft). Subsequent to placement, the berm would spread and decrease in elevation; however, to avoid impeding lagoon discharge to the ocean, a flow path should be maintained seaward of the weir. The City of Oceanside Streets Division maintains the ocean outlet at Buena Vista Lagoon. Excavation of the eastern side of the lagoon occurs 2 to 3 times each year during the winter months to keep channels open for upstream flow and to ensure that nearby residential areas are not flooded. Since this lagoon is not open to tidal flows and the City of Oceanside maintains the existing flow path to the ocean, significant adverse impacts would not occur with implementation of the proposed action. 4.2.3 South Carlsbad Coastal wetlands in the vicinity of the South Carlsbad receiver site include Agua Hedionda Lagoon, Encinas Creek, and Batiquitos Lagoon. The extent of influence of the 4-16 211603000 South Carlsbad beach fill would not be expected to reach the Agua Hedionda Lagoon to the north or Batiquitos Lagoon to the south. Vicinity "boundaries" are based on modeling (FRH 1997). Potential impacts to Encinas Creek are described below. 4.2.3.1 Encinas Creek The proposed South Carlsbad beach fill site is located directly in front of the Encinas Creek ocean outlet. The existing berm elevation adjacent to the creek is +4 m (+13 ft) MSL at the back beach. The creek maintains its flow through this beach berm. Approximately 43 m (140 ft) of sediment accretion is anticipated on the beach adjacent to the creek outlet within 12 months of the proposed fill. The proposed beach fill berm would be placed to an elevation of+1.7 m (+5.6 ft) MSL. The Batiquitos Lagoon Enhancement Project placed dredged material at this same location, to a berm elevation of+4.5 m (15 ft), approximately 2.8 m (9 ft) higher than the proposed action. Even with the significantly higher berm, impacts to the creek discharge did not occur as a result of the Batiquitos Lagoon Enhancement Project. In addition, the creek flows through a canyon surrounded by high bluffs, approximately 20 m (65 ft) high. Considering the elevation of the bluffs on either side of the creek, the berm would be overtopped and eroded by channel flow before any potential flooding would occur. Therefore, significant impacts to Encinas Creek would not occur as a result of the proposed action. 4.2.4 Encinitas Coastal wetlands identified in the vicinity of the proposed Encinitas beach fill site include Encinas Creek and Batiquitos Lagoon. Potential impacts to these wetlands are described below. 4.2.4.1 Encinas Creek The proposed Encinitas beach fill site is located approximately 3,300 m (10,800 ft) south of Encinas Creek. Sand transport modeling indicates that 12 months after sand placement, approximately 8 m (25 ft) of shoreline accretion would occur in the vicinity of Encinas Creek from the Encinitas beach fill. This shoreline advance would represent a 7 percent increase of the existing beach width at this location, which would not likely 211603000 4-17 increase the berm height adjacent to the creek outlet. Therefore, significant adverse impacts to Encinas Creek would not occur as a result of the proposed beach fill at Encinitas. 4.2.4.2 Batiquitos Lagoon The north end of the proposed Encinitas beach fill site is located directly south of Batiquitos Lagoon. Sand transport modeling indicates that approximately 35m(115ft) of sediment accretion would occur at the lagoon inlet and potentially impact tidal flows into the lagoon within 12 months of sand placement. The Batiquitos Lagoon Enhancement Project placed material immediately upcoast and downcoast of the lagoon inlet jetties, which led to the formation of offshore and internal sandbars at the lagoon inlet. Placement of the Encinitas beach fill would potentially add to the formation of sandbars and lead to shoaling and possible lagoon closure. Batiquitos Lagoon is maintained by the USFWS, the NMFS, the California State Lands Commission, the CDFG, the Port of Los Angeles, and the City of Carlsbad. A joint project to improve the lagoon, the Batiquitos Lagoon Enhancement Project, was completed in 1996. The lagoon was dredged and jetties were constructed at the lagoon inlet in order to maintain tidal flow. Jetties were designed to ensure the lagoon mouth is kept open so that sand is pushed through the inlet into the ocean and is not allowed to build up in the lagoon. Currently, maintenance dredging of the Batiquitos Lagoon ocean inlet is being performed by the CDFG. To ensure that significant impacts to lagoon inlets would not occur, a monitoring plan would be established with the approval of ACOE, in consultation with the appropriate resource agencies. Baseline profiles would be measured prior to sediment discharge and monitored through June 1, 2001. Areas that would be monitored include lagoon mouths, entrance channels, lagoon interiors, and adjacent areas. The Navy would provide mitigation for any increased rate of sand accumulation or lagoon mouth closures resulting from the proposed action above that which normally occurs, as determined by ACOE in consultation with appropriate resource agencies. Mitigation measures would consist of opening closed lagoon inlets, and/or removal of sediment accumulation at the lagoon mouths resulting from proposed fill activities. Therefore, the proposed action would not significantly impact Batiquitos Lagoon. 4-18 211603000 The Navy has obtained written assurance from SANDAG and affected municipalities that implementation of the identified monitoring, documentation, and mitigation would occur, including any other requirements related to potential effects on ocean inlets. These assurances have been formalized in a cooperative agreement (CA) between SANDAG and the Navy covering areas potentially affected by the proposed beach replenishment operations. Potential effects are assessed through sand transport modeling performed for the proposed action. Coastal wetland areas subject to the CA include Agua Hedionda, Batiquitos, San Elijo, San Dieguito, and Los Penasquitos lagoons. Although the potential effects to each of these lagoons would differ, the Navy has included each of these areas in the CA as a precautionary measure. 4.2.5 Torrey Pines Coastal wetlands in the vicinity of the Torrey Pines receiver site include San Dieguito and Los Penasquitos lagoons. The extent of influence of the Torrey Pines beach fill would not be expected to reach San Dieguito Lagoon based on vicinity "boundaries" modeling (FRH 1997). Potential impacts to Los Penasquitos Lagoon are described below. 4.2.5.1 Los Penasquitos Lagoon The northern Torrey Pines fill site would be located approximately 500 m (1,640 ft) north of the Los Penasquitos Lagoon inlet; the southern Torrey Pines fill site would be located approximately 900 m (2,950 ft) south of the lagoon. Sand transport modeling indicates that 12 months after sand placement, sediment would migrate to the lagoon inlet and widen the adjacent beach by approximately 19 m (62 ft). This represents a 13 percent increase hi the existing beach width, which could increase the potential for lagoon closure. The ocean inlet at Los Penasquitos Lagoon was closed 70 percent of the time prior to 1990 (FRH 1997). Over the years, the condition of the lagoon has ranged from complete inlet closure to periods of open tidal exchange for up to 13 months. Variables that have influenced the condition of the ocean inlet at Los Penasquitos include an extended drought from 1945 to 1977, discharge of sewage effluent from 1962 to 1972, efforts to artificially open the lagoon beginning in 1968, major storm event runoff, and accumulation of cobbles on the outer beach. Efforts to open the lagoon naturally during 211603000 4-19 the 1970s and 1980s were inadequate. The lagoon inlet would typically close rapidly after such events, although natural openings due to stormwater runoff led to longer periods of tidal flushing. Since 1990, the Los Penasquitos Lagoon Foundation has funded a sustained, successful effort to maintain tidal flushing through excavation of the sand and cobble berm blocking the inlet and main channel. This has allowed the lagoon inlet at Los Penasquitos to remain open more than 90 percent of the time over the past 7 years. The inlet maintenance strategy presently includes two excavations per year (typically during May and October) to sustain tidal flushing. This practice allows the lagoon inlet to remain open the majority of the year, with closures typically occurring once or twice a year for periods of 1 to 2 months. The Los Penasquitos Lagoon Foundation would continue the maintenance of the lagoon inlet subsequent to implementation of the proposed action. Therefore, significant impacts to Los Penasquitos Lagoon would not occur as a result of the proposed action. To ensure that there would be no increase in lagoon mouth closures, a monitoring plan would be established and mitigation would be assured for Los Penasquitos Lagoon, as described above in Section 4.2.4.2. 4.2.6 Buccaneer Beach/South Carlsbad Alternative Coastal wetlands in the vicinity of the Buccaneer Beach alternative receiver site include the San Luis Rey River, Loma Alta Creek, Buena Vista Lagoon, and Agua Hedionda Lagoon. The extent of influence of the Buccaneer Beach alternative fill site would not be expected to reach Agua Hedionda Lagoon. Vicinity "boundaries" are based on modeling (FRH 1997). Potential impacts to the San Luis Rey River, Loma Alta Creek, and Buena Vista Lagoon are described below. Coastal wetlands in the vicinity of the South Carlsbad alternative fill area include Agua Hedionda Lagoon, Encinas Creek, and Batiquitos Lagoon. Modeling results indicate that additional fill at the South Carlsbad receiver site would not affect Agua Hedionda Lagoon, Encinas Creek, or Batiquitos Lagoon beyond what would occur as a result of the proposed action. For potential effects to these wetland areas, refer to Section 4.2.3. 4-20 211603000 4.2.6.1 San Luis Rey River Sand transport modeling results indicate that sand would migrate upcoast from the Buccaneer Beach alternative fill site to the mouth of the San Luis Rey River within 12 months of sand placement. Transported fill would potentially widen the beach at MSL in this location up to 14 m (46 ft), which would result in a 23 percent increase in the length of the river mouth. However, the existing sand berm that crosses the majority of the river mouth is at a higher elevation than the predicted beach fill accumulation. Therefore, it is not likely that the beach fill would impact the overall configuration of the river mouth. Under closed river mouth conditions and during periods of low to moderate river flow, runoff could pond behind the new sand berm, spread out, and seep through the berm. During winter periods of moderate to strong stormwater runoff, the sand berm would be rapidly breached and/or overtopped. Stormwater discharge from the river is constrained by flow through eight, 91-cm-dia (36-in-dia) pipes that pass under Pacific Street. The predicted increase in sediment at this location would not be anticipated to constrain river runoff; therefore, additional maintenance would not be required upon implementation of proposed replenishment activities. The City of Oceanside Streets Division is responsible for maintaining the Pacific Street stormwater outlet on an as-needed basis for flood control. Therefore, no adverse impacts would occur upon implementation of the proposed action. 4.2.6.2 Loma Alta Creek The proposed Buccaneer Beach alternative fill site is located south of the Loma Alta Creek mouth. Sand transport modeling indicates that the MSL beach width at Loma Alta Creek would increase 18 to 21 m (60 to 70 ft) within 12 months of sand placement, which represents a 6 to 7 percent increase in beach width. The existing berm elevation adjacent to the creek is +3.2 m (+10.5 ft) MSL at Buccaneer Beach and +2.3 m (+7.5 ft) MSL at the adjacent residential property to the north. The creek maintains its flow through this berm with a creek bed elevation of approximately -0.6 to -0.8 m (-2.0 to -2.6 ft) MSL. The elevation of the berm at Loma Alta Creek would not be likely to increase as a result of fill placement at Buccaneer Beach. Additionally, the proposed fills would not cause an adverse impact to Loma Alta Creek since the City of Oceanside constructs a sand berm in 211603000 4-21 front of the creek to prevent flow between Memorial Day and Labor Day. During the wet season, the City of Oceanside excavates a temporary channel to facilitate stream flow to the ocean. Therefore, as the City would continue to ensure adequate discharge at the creek mouth, significant impacts to Loma Alta Creek would not occur as a result of implementation of the Buccaneer Beach alternative. 4.2.6.3 Buena Vista Lagoon The Buccaneer Beach alternative fill site is located north of the Buena Vista Lagoon ocean outlet. Modeling results indicate approximately 3 m (10 ft) of beach fill would accumulate in front of the lagoon within 12 months of sand placement. Accumulation of this amount of sediment would not be anticipated to create an adverse condition and would not constitute additional maintenance of the ocean outlet; therefore, significant impacts to Buena Vista Lagoon would not occur upon implementation of the Buccaneer Beach alternative. 4.3 WATER RESOURCES 4.3.1 Approach to Analysis Significance criteria for water resources impacts are based on water quality and use and associated regulations. An impact to water resources would be significant if it would (1) adversely affect water quality or endanger public health by creating or worsening health hazard conditions; (2) threaten or damage unique biological characteristics; or (3) violate established laws or regulations that have been adopted to protect or manage water resources. The following is an analysis of factors that would potentially affect the quality of water resources within the proposed project area (e.g., chemical properties and turbidity). Potential impacts to water resources would be similar at each of the proposed receiver sites due to similar quality of the receiving waters and identical operations proposed at each of the receiver sites. Therefore, general discussions of chemical properties and turbidity are included below, relative to all of the proposed replenishment sites. 4-22 211603000 4.3.2 Chemical Properties Dredged sediment from San Diego Bay was tested for compatibility with sediment found at the receiver beach site. Grain size and chemical analyses were performed on sediment samples proposed for dredging from several areas in San Diego Bay. As specified in the Homeporting EIS, sediment analyses concluded that the proposed beach fill areas are clean and of compatible gram size with the receiver beaches. Impacts to water quality would not occur due to physical or chemical characteristics of the dredged sediment. 4.3.3 Turbidity Turbidity can be caused by the presence of fine silts or clays in the water. Fine-grained materials (<63 urn) remain suspended in the water column for longer periods of time, whereas larger grain size material (>63 um) settle out faster. There is a lower percentage of fine grains in the dredged material than the native beach material. Testing has shown that the average percentage of fine material in the Oceanside Littoral Cell native sediments is approximately 3 percent above MSL and 12 percent below MSL. The higher percentage of fine grains below MSL is attributed to the fact that finer-grained materials reside at equilibrium below the shorebase (maximum extent of seasonal sand movement due to littoral transport). The average percentage of fine grains in the dredged material is approximately 3 percent (FRH 1997). Therefore, the size of the beach fill material (i.e., 97 percent greater than 63 um) would likely cause less turbidity than occurs under natural conditions. As stated in the Homeporting EIS, increased turbidity would occur along shore as a result of sediment disposal. The proposed action involves pumping a sand/sea water mixture directly onto the beach from a dredge located offshore, rather than depositing the sediments in the nearshore environment. Increased turbidity would be caused by return water from pumping operations, as suspended sediments hi the sand/sea water mixture would flow into the surf zone subsequent to pumping. However, placement of sediment on the beach would include construction of longitudinal dikes parallel to the surf line. Sand would be placed via a single discharge point behind longitudinal dikes. These dikes would retain return water and allow suspended sediments to settle out, thereby reducing turbidity hi the return water, and subsequently reducing potential water quality impacts. 211603000 4-23 Sediment pumping operations would occur in short intervals in order for suspended particles to settle out between pumping periods. The hopper dredge would take approximately 1 to 2 hours to pump a full load onto the beach, after which it would take several hours to return to San Diego Bay and reload. A minimum tune interval of 3 to 4 hours is estimated between each load. Due to operational constraints (e.g., distance of receiver beaches from loading areas, speed of the hopper dredge, and tune to hook up/unhook pump lines), pumping operations would occur only two to three times daily at the receiver beach locations. During the reloading period, turbidity in nearshore waters caused by return water from pumping operations would be able to settle before the next pumping interval began. Therefore, time intervals between pumping operations would help reduce potential water quality impacts associated with increased turbidity. Despite dike construction, large grain size, and the time interval between disposal periods, short-term increases in turbidity associated with return water from the pumping operation would still occur in the nearshore environment. In addition to a Section 404/10 permit, the proposed action must comply with an RWQCB Certification Order, which also sets conditions on proposed operations. The RWQCB conditions require that supernatant (water samples) be collected from a loaded barge three tunes a week and analyzed for polar and nonpolar oil and grease. Furthermore, weekly monitoring of bacteria contamination 30 m (100 ft) down-current of the discharge point is required per the Waste Discharge Requirements. These RWQCB conditions would help verify that no significant impacts to water quality would occur as a result of the proposed action. Significant turbidity impacts associated with the longshore transport of fill material subsequent to placement operations would not occur. Based on available gram size data (FRH 1997), the percentage of fine grains (<63 urn) in the dredged sediments would be essentially the same as (or less than) the native littoral sediments. This would be expected due to the large portion of sediments in the outer San Diego Bay channel that reside in the littoral cell. As beach fill would be anticipated to have equal or fewer fine grains than natural beach sediments, the loss of fine grains over time would be no greater than existing conditions; therefore, significant impacts would not occur upon implementation of the proposed action. 4-24 211603000 4.4 BIOLOGY 4.4.1 Approach to Analysis This section addresses potential impacts to biological resources that could result from implementation of the proposed action. Direct impacts occur when biological resources are altered, disturbed, destroyed, or removed during the course of project implementation. Other direct impacts may include the loss of foraging habitat for wildlife species and habitat disturbance that results in unfavorable substrate conditions (i.e., incompatible grain size). Indirect impacts occur when project-related activities affect biological resources later in time or in an area removed in distance. Potential indirect impacts resulting from project implementation include increased sand transport and silt deposition, which could potentially result in lagoon inlet closure and increased turbidity in the longshore environment. Both direct and indirect impacts can be classified as either temporary or permanent, depending on the duration and significance of the impact. Temporary impacts are considered short-term when impacts on biological resources are reversible over a period of time. Long-term impacts result in the irreversible removal, disturbance, or destruction of biological resources. 4.4.2 North Carlsbad 4.4.2.1 Sand Deposition Approximately 420,510 m3 (550,027 cy) of sand would be placed within the intertidal zone at North Carlsbad. The fill area would cover approximately 1.2 km (0.7 mi) of shoreline and extend offshore about 130 m (426 ft) from the back beach (back of the existing beach) (Figure 3-1). Sand placement would result in the direct burial and death of nonmobile epibenthic and benthic invertebrates; however, this would be a short-term impact as recolonization of the area would occur rapidly. Mobile invertebrates, such as crustaceans, would be expected to move into the area within days of cessation of sand placement and other organisms would be expected to recolonize within 6 to 12 months (Butler Roach 1995). Because the effect would be temporary and would not directly impact any sensitive species, impacts to intertidal invertebrates would be considered insignificant. 211603000 4-25 Nonmobile invertebrates in the subtidal area would also be buried by sediments that are washed offshore from implementation of the proposed project. Since this is a natural process, most subtidal invertebrates are adapted to shallow burial by sediments. Mobile invertebrates would move vertically within the sandy substrate or horizontally to deeper waters to avoid burial; therefore, this impact would be considered insignificant. No sensitive marine resources are located hi the fill area of the North Carlsbad receiver beach. Sensitive marine resources are present in the vicinity and include vegetated subtidal reefs and nearshore reefs with giant kelp. The shallow subtidal reefs provide habitat for feather boa kelp, surfgrass, and sea fans. The closest reef occurs approximately 200 m (660 ft) offshore of the back beach, with more extensive scattered reefs occurring greater than 300 m (990 ft) downcoast of the fill area, towards the mouth of Agua Hedionda Lagoon (refer to Figure 3-1). No short-term or long-term adverse impacts to these resources would be expected, as sand placement activities would avoid areas that contain sensitive marine resources and are designed to mimic the natural beach slope of the existing beach profile. Natural sand transport is a function of seasonal cycles that move sand offshore in the winter and then back onto the beach in the summer. Sand movement would be similar to natural conditions and would not move farther offshore than 275 m (908 ft) seaward of the back beach and 2,000 m (6,600 ft) upcoast or downcoast of the beach fill. Sand transport is expected to mimic the existing natural conditions and the average increase in sand thickness over a one year period is anticipated to be 0.3 m (10 in) (FRH 1997). The nearest surfgrass bed is located approximately 175 m (578 ft) offshore of the back beach, and the nearest kelp bed is found greater than 300 m (990 ft) offshore. The nearest surfgrass beds may be subject to short-term impacts of increased sand transport. However, the surfgrass beds are persistent and are adapted to natural seasonal sand movement, and therefore, sand placement and transport would not be expected to significantly affect them. Kelp beds are located far enough away from beach replenishment activities as to not be significantly affected. Although no significant impacts to sensitive marine resources are anticipated at the receiver sites, the Navy would prepare and implement a monitoring plan to verify significant impacts do not occur. The program would include pre-discharge baseline studies and post discharge monitoring. The monitoring program would be effective from the date of issuance of an ACOE permit through June 1, 2001 to confirm that sand 4-26 211603000 discharge operations would not result in any long-term net loss of sensitive marine resources. The monitoring plan, pre-discharge mapping effort, and subsequent monitoring would be conducted by a biologist familiar with southern California marine waters and biological habitats. The Navy would submit the monitoring plan to the ACOE for approval, in consultation with the resource agencies at least 15 working days prior to initiating onshore discharge at the receiver beaches. The monitoring reports would be submitted to the ACOE and resource agencies by January 30th of each year. The Navy would mitigate any significant, long-term adverse impacts to sensitive marine resources that were documented by the monitoring plan to have resulted from discharge activities. Mitigation would be the restoration of like habitat at a 1:1 ratio as a first priority. Consideration would be given to the construction of artificial reefs as mitigation to offset project impacts at a 1:1 ratio if like habitat restoration efforts were not feasible as determined by the ACOE, in consultation with the resource agencies. Should the ACOE and/or the resource agencies require mitigation, total mitigation costs would not exceed $400,000 to satisfy the requirements of Phase II beach replenishment. Mitigation costs for Phase I beach replenishment efforts would not exceed $700,000; therefore, total mitigation costs for beach replenishment operations associated with the CVN homeporting project would not exceed $1.1 million. During beach replenishment operations, some sand would move into the surf zone and be suspended in the water column, causing an increase hi turbidity. Increases in turbidity could potentially impact sensitive marine resources such as surfgrass and kelp populations. However, impacts would not be expected to be significant because the sand proposed for beach replenishment has a smaller percentage of fine material than what is presently on the beaches, and the area is naturally turbid due to constant wave action (FRH 1997). In addition, the sand would be placed behind longitudinal dikes so that most of the material would settle out, thus minunizing turbidity. Impacts to fishes, birds, and marine mammals resulting from sand deposition would not be considered significant. These are mobile organisms that can easily leave the area for similar foraging habitat. Ample foraging habitat is found adjacent to the North Carlsbad receiver site both onshore and offshore. Onshore habitat, similar to the receiver beach, is found south of Agua Hedionda Lagoon. Offshore habitat not affected by pumping operations would be found north and south of the receiver area, dependent upon the size of the turbidity plume generated by pumping operations. As turbidity would not be 211603000 4-27 significant as a result of the proposed action, suitable offshore foraging habitat would be anticipated in the vicinity of the receiver beach during replenishment operations. Because these organisms can readily move to adjacent areas and the displacement would be temporary, this impact would be considered insignificant. California brown pelicans could be impacted in the immediate area of the receiving site by a temporary reduction in their prey base. However, pelicans, like their fish prey, can easily forage in adjacent offshore areas. California least terns and western snowy plovers are not known to nest at the North Carlsbad receiver beach and are not expected to nest in the area in the future because of human disturbance. Terns and plovers may forage in the waters offsite, but can forage adjacent to the site if fish vacate the area or an increase in turbidity limits their foraging ability. Therefore, no significant impacts to sensitive species would occur upon implementation of the proposed action. California grunion may spawn on the North Carlsbad receiver beach during the sand placement period. Replenishment activities could potentially bury their eggs or change the beach profile resulting hi mortality. The Navy would enter into a contract with a biologist that has specific knowledge of the California grunion to monitor spawning activities at the discharge sites during expected grunion runs, as predicted by the CDFG. If grunion were observed spawning during discharge operations, disposal of sand would immediately cease in the vicinity of spawning activities and a buffer zone would be established surrounding the area of spawning. The buffer zone would extend 20 m (65 ft) shoreward of the highest water mark at the spawning area, and run 30 m (100 ft) upcoast and 30 m (100 ft) downcoast from the spawning area. A sand dike, parallel to the shoreline above the 20 m (65 ft) buffer zone, would be constructed along the entire 60 m (200 ft) lateral extent of the buffer zone to ensure that the discharge water would not enter the spawning area. The spawning areas would be recorded and mapped, and a written report would be provided to the ACOE and the resource agencies within 24 hours of the spawning event. The buffer zone would be in place for a minimum of 14 days (the period of time for eggs to hatch). This would mitigate impacts to the grunion and would allow sand replenishment activities to continue hi areas not affected by spawning. 4.4.2.2 Barge Placement and Anchoring The proposed beach replenishment operations at the North Carlsbad receiver site would be expected to occur from October to mid-November 1997. The hopper dredge would 4-28 211603000 not be in place for the entire duration as it would travel from San Diego Bay to North Carlsbad on a daily basis. Anchor lines for the mono buoy and pump lines to shore, however, would be permanently placed for the duration of the project. Pump lines and anchor points would be surveyed at least 30 days prior to the start of operations and placed to minimize impacts of sensitive marine resources (e.g., vegetated reefs). Therefore, pump lines and anchor points would not result in significant impacts to these sensitive resources. The dredge would not negatively impact fish or invertebrate communities in the area and may actually attract fish to the area by providing spatial relief. Furthermore, the dredge would not significantly disturb birds or marine mammals as it would not be a permanent feature and could be easily avoided. 4.4.2.3 Coastal Wetlands No significant impacts to wetland organisms would be anticipated to occur as a result of sand placement at the North Carlsbad receiver beach. As discussed in Section 4.2, SANDAG is responsible for insuring that the local jurisdictions monitor lagoon inlets and river/creek outlets located in the vicinity of the North Carlsbad receiver site. Any measures needed to ensure inlet/outlet stability would be implemented by the local jurisdictions. For further discussion of potential impacts to Buena Vista and Agua Hedionda Lagoons, refer to Section 4.2.1. 4.4.3 South Carlsbad 4.43.1 Sand Deposition Approximately 420,510 m3 (550,027 cy) of sand would be placed within the intertidal zone at South Carlsbad. The fill area would cover approximately 2.2 km (1.4 mi) of shoreline and extend offshore about 130 m (426 ft) from the back beach (Figure 3-2). Potential impacts due to sand placement at South Carlsbad are similar to those described for the North Carlsbad site. Nonmobile and epibenthic invertebrates present could be buried by sediment deposition, although this impact would not be considered significant as the populations would be expected to recover quickly and burial would affect only a limited area. No sensitive marine resources are located in the fill area of the South Carlsbad receiver beach. However, marine resources are present in the vicinity and include vegetated 211603000 4-29 subtidal reefs and nearshore reefs with giant kelp (refer to Figure 3-2). The subtidal reefs provide habitat for feather boa kelp, surfgrass, and sea fans. The closest reefs occur approximately 200 m (660 ft) from the back beach. No short-term or long-term significant impacts to these resources would be expected, as sand placement activities would avoid areas that contain sensitive marine resources and are designed to mimic the natural beach slope of the existing beach profile. Natural sand transport is a function of seasonal cycles that move sand offshore in the winter and then back onto the beach in the summer. Sand movement would be similar to natural conditions and would not move farther offshore than 300 m (990 ft) seaward of the back beach and 3,000 m (9,900 ft) upcoast or downcoast of the beach fill (FRH 1997). The average increase in sand thickness is anticipated to be 0.2 m (6.5 in) (FRH 1997). The nearest vegetated subtidal reefs are located approximately 200 m (660 ft) from the back beach. Short- or long-term significant impacts are not expected because these sensitive marine resources have adapted to natural seasonal sand movement. Therefore, sand placement and transport would not significantly affect either of these sensitive marine resources. Although significant impacts to sensitive marine resources would not occur, a monitoring program has been established and is similar to the program described for North Carlsbad. During beach replenishment operations, some sand would move into the surf zone and be suspended in the water column causing an increase in turbidity. Increases in turbidity could potentially impact sensitive marine resources such as surfgrass and kelp populations. However, impacts would not be significant because the sand being used for beach replenishment has a smaller percentage of fine material than what is presently on the beaches and the area is naturally turbid due to constant wave action (FRH 1997). In addition, the sand would be placed behind longitudinal dikes so that most of the material would settle out, thus minimizing turbidity. Impacts to fishes, birds, and marine mammals resulting from sand deposition would not be significant as these are mobile organisms that can easily leave the area for similar foraging habitat. California grunion may spawn on the South Carlsbad receiver beach during the sand placement period. If grunion were observed spawning, measures to avoid impacts as described for North Carlsbad would be taken. 4-30 211603000 Sensitive avian species in the South Carlsbad area include the California least tern and the Western snowy plover. The tern utilizes offshore waters for foraging activities in the vicinity of the receiver sites and the plover utilizes sandy intertidal habitat for foraging. Replenishment operations could affect the intertidal zone in the receiver areas by causing short-term increases in turbidity in longshore waters, thereby causing a reduction in the forage base. However, these birds are mobile and would be able to move to adjacent beach areas or non-impacted waters for foraging activities. Therefore, no significant impacts to sensitive species would occur as a result of implementation of the proposed action. 4.4.3.2 Barge Placement and Anchoring The proposed beach replenishment operations at the South Carlsbad receiver site are expected to occur from mid-November 1997 to January 1998. Placement and operation of the hopper dredge, mono buoy, and pump lines would be the same as those described for North Carlsbad receiving site. The pump lines would not negatively impact fish or invertebrate communities in the area and may actually attract fish to the area by providing spatial relief. The dredge would not significantly disturb birds or marine mammals as it would not be a permanent feature and could be easily avoided. 4.4.3.3 Coastal Wetlands No significant impacts to wetland organisms would be anticipated as a result of sand placement at the South Carlsbad receiver beaches. As discussed in Section 4.2, local jurisdictions are responsible for monitoring lagoon inlets and river/creek outlets located in the vicinity of the South Carlsbad receiver areas. Any measures needed to ensure inlet/outlet stability would be implemented by the local jurisdictions. For further discussion of potential impacts to Encinas Creek and Batiquitos Lagoon, refer to Section 4.2.3. 211603000 4-31 4.4.4 Encinitas 4.4.4.1 Sand Deposition Sensitive marine resources at the Encinitas fill area include rocky intertidal reefs, intertidal/shallow subtidal vegetated reefs (including feather boa kelp, surfgrass, and sea fans), and nearshore reefs with giant kelp (refer to Figure 3-3). Approximately 871,620m3 (1,140,079 cy) of sand would be placed within the intertidal zone at Encinitas. The fill area would cover approximately 4.4 km (2.7 mi) of shoreline and extend about 130 m (426 ft) from the back beach (Figure 3-3). Sand placement at Encinitas would result hi the direct burial of approximately 243,010 m2 (290,666 yd2) of rocky intertidal habitat and vegetated subtidal reefs. Burial would occur on the order of 2 to 3 m (6.6 to 10 ft) throughout this area. Due to direct burial and potential long-term impacts to marine resources at the Encinitas receiver beach, this site has been rejected for onshore beach replenishment. Sand placement at the Encinitas site would be required to avoid direct burial of sensitive marine resources and would be subject to the same mitigation measures as identified for North Carlsbad (in Section 4.4.2.1). Implementation of the proposed action at this site would greatly increase the project mitigation cost due to potential long-term impacts to sensitive marine resources. Natural sand transport is a function of seasonal cycles that move sand offshore in the winter and then back onto the beach in the summer. Modeling indicates sand movement would be similar to natural conditions and would not move farther offshore than 400 m (1,312 ft) seaward of the back beach and 4,500 m (14,850 ft) upcoast or downcoast of the beach fill (FRH 1997). However, surfgrass habitats and vegetated reefs are located hi the fill footprint and directly offshore for approximately 300 m (990 ft) from the back beach. Also, because the nearest high relief vegetative reef is found approximately 125 m (413 ft) from the back beach (approximately 25 m [75 ft] from the offshore edge of the fill area), sand placement and transport would cause short-term adverse impacts to both of these sensitive marine resources. During beach replenishment operations, some sand will move into the surf zone and be suspended in the water column, causing an increase in turbidity. Increases in turbidity could potentially impact sensitive marine resources such as surfgrass and kelp 4-32 211603000 populations. However, impacts would not be significant because the sand that would be used for beach replenishment has a smaller percentage of fine material than what is presently on the beaches and the area is naturally turbid due to constant wave action (FRH 1997). In addition, the sand would be placed behind longitudinal dikes so that most of the material would settle out, thus minimizing turbidity. Nonmobile epibenthic and benthic invertebrates present on the hard substrates could be buried by sediment deposition. However, this impact would not be significant as populations are expected to recover quickly. Impacts to fishes, birds, and marine mammals resulting from sand deposition would not be considered significant as these are mobile organisms that can easily leave the area for similar foraging habitat. Due to the lack of available sand, California grunion are not expected to spawn on the Encinitas receiver beaches during sand placement. However, if grunion were observed spawning, measures to avoid impact as described for North Carlsbad would be taken. 4.4.4.2 Barge Placement and Anchoring The proposed beach replenishment operations at the Encinitas receiver site would be expected to occur from January to mid-April 1998. Placement and operation of the hopper dredge, mono buoy, and pump lines would be the same as those described for North Carlsbad receiving site. The dredge would not negatively impact fish or invertebrate communities in the area and might actually attract fish to the area by providing spatial relief. The dredge would not significantly disturb birds or marine mammals as it would not be a permanent feature and could be easily avoided. Extensive kelp beds are located directly offshore of the Encinitas receiver site. Portions of the kelp beds could be distressed by placement of sinker lines. If the equipment were moored or placed directly on the kelp plants, the plants could be crushed or damaged. The kelp beds would be surveyed at least 30 days prior to pumping operations. As shown in Figure 3-3, the mono buoy and sinker line would be placed to minimize impacts to the kelp bed areas. Therefore, significant impacts to existing kelp beds would not be anticipated to occur upon implementation of the proposed action. 211603000 4-33 4.4.4.3 Coastal Wetlands Significant impacts to wetland organisms would not be anticipated to occur as a result of sand placement at the Encinitas receiver beach. As discussed in Section 4.2, local jurisdictions are responsible for monitoring lagoon inlets and river/creek outlets located in the vicinity of the Encinitas receiver area. Any measures needed to ensure inlet/outlet stability would be implemented by the local jurisdictions. For further discussion of potential impacts to Batiquitos Lagoon, refer to Section 4.2.4.2. 4.4.5 Torrey Pines 4.4.5.1 Sand Deposition Approximately 496,970 m3 (650,037 cy) of sand would be placed within the intertidal zone at the two Torrey Pines receiver beaches. The fill area would cover approximately 0.9 km (0.5 mi) of shoreline at North Torrey Pines and 0.7 km (0.4 mi) of shoreline at South Torrey Pines. The fill would extend offshore about 130 m (426 ft) from the back beach (Figure 3-4). Potential impacts at Torrey Pines would be similar to those described for North Carlsbad receiver site. Nonmobile epibenthic and benthic invertebrates present on the sandy substrates could be buried by sediment deposition. However, this impact would not be significant as the populations would be expected to recover quickly and burial would affect only a limited area. Impacts to fish, birds, and marine mammals resulting from sand deposition would not be considered significant as these are mobile organisms that can easily leave the area for similar foraging habitat. California grunion might spawn on the north Torrey Pines receiver beach during the sand placement period, and if grunion were observed spawning, measures to avoid impact as described for North Carlsbad would be taken. No sensitive marine resources are located in the vicinity of the north Torrey Pines fill area. However, sensitive marine resources are located in the vicinity of the southern Torrey Pines fill area and include vegetated shallow subtidal reefs and nearshore reefs with giant kelp (refer to Figure 3-4). The shallow subtidal reefs provide habitat for feather boa kelp, surfgrass, and sea fans. The closest reefs occur approximately 265 m (870 ft) offshore of the back beach; therefore, no short- or long-term significant impacts would occur to these resources as sand placement activities are designed to avoid areas 4-34 211603000 that contain sensitive marine resources and to mimic the natural beach slope of the existing beach profile. Natural sand transport is a function of seasonal cycles that move sand offshore in the whiter and then back onto the beach hi the summer. Sand movement would be similar to natural conditions and would not move sand farther offshore more than 350 m (1,148 ft) seaward of the back beach and 3,000 m (9,900 ft) upcoast or downcoast of the beach fill (FRH 1997). The nearest surfgrass bed is located approximately 300 m (990 ft) offshore of the back beach, and the nearest kelp bed is found approximately 500 m (1,650 ft) offshore. Surfgrass and kelp beds in these areas are persistent and are adapted to natural seasonal sand movement, and therefore, sand placement and transport would not significantly affect either of these sensitive marine resources. Although no significant impacts to sensitive marine resources would occur, a monitoring program has been established and is similar to the program described for North Carlsbad. During beach replenishment operations, some sand would move into the surf zone and be suspended in the water column, causing an increase hi turbidity. Increases hi turbidity could potentially impact sensitive marine resources such as surfgrass and kelp populations. However, impacts would not be significant because the sand that would be used for beach replenishment has a smaller percentage of fine material than what is presently on the beaches and the area is naturally turbid due to constant wave action (FRH 1997). In addition, the sand would be placed behind longitudinal dikes so that most of the material would settle out, thus minimizing turbidity. Sensitive avian species hi the Torrey Pines area include the California least tem and the Western snowy plover. The tem utilizes offshore waters for foraging activities hi the vicinity of the receiver sites and the plover utilizes sandy intertidal habitat for foraging. Replenishment operations could affect the intertidal zone hi the receiver areas by causing short-term increases hi turbidity hi nearshore waters, thereby causing a reduction in the forage base. However, these birds are mobile and would be able to move to adjacent beach areas or non-impacted waters for foraging activities. Therefore, no significant impacts to sensitive species would occur upon implementation of the proposed action. 211603000 4-35 4.4.5.2 Barge Placement and Anchoring The proposed beach replenishment operations at the Torrey Pines receiver site would be expected to occur from mid-April to June 1998. Placement and operation of the hopper dredge, mono buoy, and pump lines would be the same as those described for the North Carlsbad receiving site. The dredge would not negatively impact fish or invertebrate communities in the area and might actually attract fish to the area by providing spatial relief. The dredge would also not significantly disturb birds or marine mammals as it would not be a permanent feature and could be easily avoided. 4.4.5.3 Coastal Wetlands No significant impacts to wetland organisms would be anticipated to occur as a result of sand placement at the Torrey Pines receiver beaches. As discussed in Section 4.2, local jurisdictions are responsible for monitoring lagoon inlets and river/creek outlets located in the vicinity of the Torrey Pines receiver areas. Any measures necessary to ensure inlet/outlet stability would be implemented by the local jurisdictions. For further discussion of potential impacts to Los Penasquitos Lagoon, refer to Section 4.2.5. 4.4.6 Buccaneer Beach/South Carlsbad Alternative 4.4.6.1 Sand Deposition If the Encinitas site is excluded from the beach replenishment plan, the beach fill intended for Encinitas would be redistributed to Buccaneer Beach in South Oceanside and the South Carlsbad receiver beach. Approximately 580,245 m3 (758,960 cy) of sand would be placed at Buccaneer Beach (refer to Figure 3-1), and an additional 291,375 m3 (381,119 cy) of sand would be placed at South Carlsbad (refer to Figure 3-2), bringing the total at South Carlsbad to approximately 711,885 m3 (931,115 cy). The fill area at Buccaneer Beach would cover approximately 1.4 km (0.9 mi) of shoreline, while the South Carlsbad additional fill would extend approximately 600 m (1,968 ft) beyond the proposed fill area. In both cases, the offshore extent of the fill would be about 130 m (426 ft) from the back beach. The placement of sand at the Buccaneer Beach receiver area could result in the burial and death of nonmobile epibenthic and benthic invertebrates. However, this would be a 4-36 211603000 temporary impact as recolonization of the area would occur rapidly. Mobile invertebrates, such as crustaceans, would be expected to move into the area within days of cessation of sand placement and other organisms would be expected to recolonize within 6 to 12 months (Butler Roach 1995). Because the effect would be temporary and would not directly impact any sensitive species, impacts to invertebrates would be considered insignificant. Nonmobile invertebrates in the subtidal area could also be buried by sediments that are washed offshore from implementation of the proposed project. Since this is a natural process, most subtidal invertebrates are adapted to shallow burial by sediments. Mobile invertebrates would move vertically within the sandy substrate or horizontally to deeper waters to avoid burial; therefore, this impact would be considered insignificant. No subtidal rocky reef, kelp bed, or surfgrass habitats are located in the vicinity of the Buccaneer Beach receiver area (refer to Figure 3-1). Therefore, no impacts to these sensitive marine resources would occur due to sediment placement or transport. Potential impacts due to placement of additional sand at the South Carlsbad alternative receiver beach would be similar to those described for the proposed action at South Carlsbad (see Section 4.4.2.1). Sand movement would be similar to natural conditions and would not move farther offshore than 400 m (1,320 ft) seaward of the back beach and 3,000 m (9,900 ft) upcoast or downcoast of the beach fill (FRH 1997). No surfgrass habitat is present; however, a vegetated reef with feather boa kelp is located approximately 60 m (198 ft) offshore of the additional fill area (approximately 175 m [578 ft] from the back beach). Sand placement as a result of project implementation would not directly affect this sensitive marine resource. Sand transport after placement would also not significantly affect this resource, as kelp beds are persistent and are adapted to natural seasonal sand movement. Although significant impacts to sensitive marine resources would not occur, a monitoring program has been established and is similar to the program described for North Carlsbad. Impacts to fishes, birds, and marine mammals resulting from sand deposition would not be considered significant as these are mobile organisms that can easily leave the area for similar foraging habitat. 211603000 4-37 Due to the lack of available sand, California grunion would not be expected to spawn on the Buccaneer Beach receiver beaches during sand placement. However, if grunion were observed spawning, measures to avoid impact as described for North Carlsbad would be taken. Sensitive avian species in the Buccaneer Beach/South Carlsbad area include the California least tern and the western snowy plover. The tem utilizes offshore waters for foraging activities in the vicinity of the receiver sites and the plover utilizes sandy intertidal habitat for foraging. Replenishment operations could affect the intertidal zone in the receiver areas by causing short-term increases in turbidity in longshore waters, thereby causing a reduction in the forage base. However, these birds are mobile and would be able to move to adjacent beach areas or non-impacted waters for foraging activities. Therefore, no significant impacts to sensitive species would occur upon implementation of the proposed action. 4.4.6.2 Barge Placement and Anchoring Should the alternative plan be implemented, sand placement operations would be expected to occur at Buccaneer Beach from mid-July to October 1997; at North Carlsbad from November 1997 to January 1998; at South Carlsbad from January to April 1998; and at Torrey Pines from April to June 1998. Operations for the South Carlsbad and Torrey Pines receiver sites are the same as previously described. Placement and operation of the hopper dredge, mono buoy, and pump lines for Buccaneer Beach would be the same as those described for the North Carlsbad receiving site. The dredge would not negatively impact fish or invertebrate communities in the area and might actually attract fish to the area by providing spatial relief. Furthermore, the dredge would not significantly disturb birds or marine mammals as it would not be a permanent feature and could be easily avoided. 4.4.63 Coastal Wetlands No significant impacts to wetland organisms would be anticipated as a result of sand placement at the Buccaneer Beach receiver site. As discussed in Section 4.2, local jurisdictions are responsible for monitoring lagoon inlets and river/creek outlets located in the vicinity of the Buccaneer Beach receiver areas. Any measures needed to ensure 4-38 211603000 inlet/outlet stability would be implemented by the local jurisdictions. For further discussion of potential impacts to Buena Vista Lagoon, refer to Section 4.2.6. 4.5 LAND USE AND RECREATION 4.5.1 Approach to Analysis The significance of potential land use impacts associated with implementation of the proposed action is based on the level of land use sensitivity in areas that would be affected by the proposed action. In general, land use and recreational impacts would be significant if they would (1) be inconsistent or noncompliant with applicable land use patterns or policies; (2) preclude the viability of existing land use activities; (3) preclude continued use or occupation of an area; (4) be incompatible with adjacent or vicinity land use to the extent that public health or safety is threatened; or (5) impact the quality or quantity of existing recreational opportunities. 4.5.2 North Carlsbad Implementation of the proposed action would not change existing uses at the North Carlsbad site. Furthermore, the proposed action would not conflict with the goals and policies contained in the Carlsbad General Plan and the LCP. Recreational activities most likely to be disturbed by beach replenishment activities would include surfing, swimming, diving, surf fishing, sport fishing, sailing, and other beach uses such as picnicking and sun bathing. Because of public safety concerns associated with heavy equipment operations on the beach, replenishment operations would require that the receiver beach site and offshore area be closed temporarily to the public. Closure and restricted access to the area would result in a redistribution of beach activities to surrounding areas. This would be a temporary localized effect and would not result in a permanent significant condition. Without beach replenishment, beach use would decline as beach conditions continue to deteriorate (e.g., erosion). Upon completion of beach replenishment operations, recreational activities would resume and would be enhanced. Therefore, the proposed action would result in a beneficial impact by ensuring long-term recreational uses. 211603000 4-39 As discussed in the Homeporting EIS, changes to wave action and consequently to surfing conditions could occur if dredged material were placed in the longshore area. With the movement of beach sand through littoral processes, offshore bars could develop over tune, thereby affecting beach breaks dependent on the formation of sandbars. However, as changes in the formation of offshore sandbars is a naturally occurring event, this effect would not be considered a significant impact. No reef surf breaks are located in the vicinity of the North Carlsbad receiver site; therefore, no impacts to reef breaks would occur. 4.5.3 South Carlsbad Land use impacts to the South Carlsbad receiver area would be similar to those for the North Carlsbad site. Beach replenishment at South Carlsbad would not conflict with the goals and policies contained in the Carlsbad General Plan or the San Diego Coastal State Park System General Plan. Closure of the South Carlsbad receiver beach would be a temporary localized effect and would not result in a permanent significant condition. As with the North Carlsbad replenishment effort, the proposed action would cause a redistribution of recreational beach activities to surrounding areas. Potential impacts to recreational users at the State Beach Campground could occur due to restricted access to the State Beach adjacent to the campground. However, replenishment efforts would not cause the closure of the entire beach area below the campground; the proposed operations would occur only on the northern portion of the State Beach (refer to Figure 1-3). Thus, campground visitors would maintain State Beach access adjacent to the southern portion of the campground. As direct beach access from South Carlsbad State Beach Campground would be maintained during proposed operations, significant impacts to recreational users would not occur as a result of implementation of the proposed action. Similar to the North Carlsbad replenishment site, beach surf breaks located along the South Carlsbad site could be affected by the formation of offshore sandbars associated with transported beach fill from the proposed action. However, this effect would be considered insignificant as the formation of offshore sand bars is a naturally occurring event. No reef surf breaks are identified in the vicinity of the South Carlsbad site; therefore, no impacts to reef breaks would occur. 4-40 211603000 4.5.4 Encinitas Land use impacts to the Encinitas receiver area would be similar to those for the Carlsbad sites. Beach replenishment at Encinitas would not change any existing uses at the site, nor conflict with the goals and policies contained hi the Encinitas General Plan and LCP. As with the Carlsbad sites, the proposed action would cause a redistribution of recreational beach activities to surrounding areas. This would be a temporary localized effect and would not result in a permanent significant condition. Upon completion of beach replenishment operations, recreational activities would resume and would be enhanced. The proposed action would therefore result in a beneficial impact by ensuring long-term recreational uses. Surf breaks hi the vicinity of the Encinitas receiver site could be affected by the formation or alteration of offshore sandbars associated with transported beach fill. Popular surf breaks in the area include "Tomato Patch," "Grandview," "Beacon's," and "Stone Steps." These are all beach surf breaks that are influenced by subtidal rocky reefs, which could potentially be impacted by sediment accretion at the reefs. Sediment accumulation in the vicinity of the Encinitas receiver site is expected within 450 m (1,500 ft) of the existing beach. Due to the proximity of subtidal reefs to the proposed beach fill, potentially adverse impacts to surf breaks hi front of the site could occur as a result of the proposed action. Popular reef-supported surf breaks south of the proposed Encinitas receiver site (e.g., "Boneyards" and "Swami's") would not be affected by transported beach fill from the proposed action. 4.5.5 Torrey Pines Land use impacts to the Torrey Pines receiver sites would be similar to those for the other proposed receiver sites. Beach replenishment at Torrey Pines would not conflict with the goals and policies contained in the City of San Diego General Plan, the Del Mar General Plan, or the San Diego Coastal State Park System General Plan. Closure of the Torrey Pines receiver sites would be a temporary localized effect and would not result hi a permanent significant condition. As with the other receiver areas, the proposed action would cause a redistribution of recreational beach activities to surrounding areas. Potential impacts to recreational users 211603000 4-41 at Torrey Pines State Reserve could occur due to restricted access to the State Beach adjacent to the Reserve. However, replenishment efforts would not cause the closure of the entire beach area below the Reserve. Proposed operations would occur north of the Beach Trail access to the State Beach (refer to Figure 1-5). Hikers and other recreational visitors would have access to the State Beach during proposed replenishment operations. Therefore, as direct beach access from Torrey Pines State Reserve would be maintained during proposed operations, significant impacts to recreational users would not occur upon implementation of the proposed action. Two popular reef surf breaks are located north of the northern Torrey Pines fill site, "8th Street" and "South Del Mar." Sand transport modeling indicates that sediment accretion could occur at the base of these reefs within 12 months of sand placement, which could adversely affect the surf breaks at these locations. However, sediment movement through these reefs occurs on a seasonal basis. Therefore, sediment transported from the North Torrey Pines fill site would not be anticipated to significantly impact these reef surf breaks. Adverse effects to beach surf breaks occurring along the Torrey Pines receiver sites would not be anticipated to occur. The proposed action would create changing surf conditions from the formation and alteration of offshore sandbars; however, as this is a naturally occurring event, it would not be considered significant. 4.5.6 Buccaneer Beach/South Carlsbad Alternative Land use impacts to the Buccaneer Beach alternative receiver area would be similar to those for the proposed receiver sites. Beach replenishment at Buccaneer Beach in South Oceanside would not change any existing uses at the site, nor conflict with goals and policies contained in the Oceanside General Plan and LCP. Closure of the alternative receiver beach would be a temporary localized effect and would not result in a permanent significant condition. Impacts to surf breaks would be similar to those at the North Carlsbad receiver site. For land use impacts associated with additional fill at the South Carlsbad receiver site, refer to Section 4.5.2. 4-42 211603000 4.6 SAFETY AND ENVIRONMENTAL HEALTH 4.6.1 Approach to Analysis For this analysis, determination of significance of potential safety and environmental health impacts is based on the level of safety precautions that would be implemented during replenishment activities. An impact to safety and environmental health would be significant if it would (1) create a health hazard or potential health hazard or (2) expose people to potential health hazards. In addition to evaluating these concerns, this analysis also assesses safety concerns associated with the development of a scarp as a result of beach replenishment. A scarp is defined as the cut in the beach berm face caused by wave action. Scarp height is a function of the breaking wave height and the elevation of the existing beach berm. Scarps develop naturally along the beach profile and vary in height due to significant changes in the beach profile (i.e., a drastic drop in elevation). 4.6.2 Proposed Beach Receiver Sites The following analysis is applicable to the proposed North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines receiver sites, as well as the Buccaneer Beach/South Carlsbad alternative sites. Implementation of the proposed action would create an unsafe situation on receiver beaches during sand placement, due to the amount of heavy equipment used to grade and dress the beaches. During discharge operations, the receiver areas would be closed to ensure public safety. The closure would affect the existing beach and offshore areas between the hopper dredge and the receiver beach. A buffer zone of 30 m (100 ft) would be provided between the operation area and any open public beach areas. The Navy would provide all necessary safety measures in the vicinity of the receiver beaches, including fencing, barricades, and flagmen, as necessary. Additionally, an approximate 150 m by 150 m (500 ft by 500 ft) buffer area would be maintained around the hopper dredge offshore waters, to allow proper anchoring and pump line operation. To ensure that no vessels would enter the offshore restricted zone, the anchoring area would be included in the Notice to Mariners, which is overseen by the U.S. Coast Guard. 211603000 4-43 Significant impacts to public safety would not occur upon implementation of the proposed action. As stated above, a scarp is defined as the cut in the beach berm face caused by wave action. Large scarps may result in safety hazards due to significant changes in the beach profile (i.e., a drastic drop in elevation). Because scarps are a function of beach berm height, placement of fill on the receiver beaches would not increase scarp height, provided fill is placed to the height of the existing beach berm (FRH 1997). The proposed action specifies that beach fill would not be placed above the height of the existing beach berm. Therefore, safety impacts due to increased scarp heights would not occur upon implementation of the proposed action. 4.7 AESTHETICS 4.7.1 Approach to Analysis Determination of the significance of potential impacts to visual resources in a certain area is based primarily on the level of visual sensitivity. Visual sensitivity is defined as the degree of public interest in a visual resource and concern over adverse changes in the quality of that resource. In general, an impact to a visual resource would be significant if implementation of the proposed action would (1) result in a substantial alteration to an existing visual setting or (2) create an aesthetically offensive site open to public view. San Diego's coastal beaches are one of the region's greatest visual resources. For this reason, the coastal areas of San Diego County are considered a highly sensitive visual resource. Coastal beaches offer scenic high quality views that are considered a trademark of the southern California area. Any construction or operation that would cause permanent degradation of existing views along coastal beaches would be considered significant. Potential impacts to visual resources would be similar at each of the proposed receiver sites due to their similar coastal locations. Therefore, the following discussion is relative to all of the proposed receiver sites. 4.7.2 Proposed Beach Receiver Sites The proposed action would alter existing views along the receiver beaches during proposed beach replenishment operations. Proposed operations include a hopper dredge 4-44 211603000 anchored offshore, beach grading equipment, and several construction personnel operating the pump line and associated equipment. Pumping and construction operations would degrade existing coastal views in each area on a temporary basis during the scheduled operating time. However, the receiver beaches would be enhanced subsequent to beach replenishment operations. Sand replenishment would widen existing beaches, thereby eliminating views of eroded beach areas. No long-term adverse visual impacts would occur upon implementation of the proposed action. Beach fill material associated with disposal operations could be darker in color than existing beach sand due to organic materials in the sediment; however, fill material would be washed and reworked by waves, bleached under exposure to the sun, and mixed with existing sand. Any discoloration of the sediment would be short term (ACOE 1984); no permanent adverse visual conditions would result from discoloration of fill materials at the receiver beaches. 4.8 STRUCTURES AND UTILITIES 4.8.1 Approach to Analysis Analysis of impacts conducted for this EA includes the identification of structures and utilities that could be affected by implementation of the proposed action. Impacts to structures and utilities would be significant if they would (1) result in the need for new systems or (2) result in substantial alterations to existing systems. Because an increase in service demand would not occur with the proposed action, this analysis focuses on displacement or disruption of structures and utilities. Information contained in this section is derived from the Beach Sand Transport and Sedimentation Report (FRH 1997). 4.8.2 North Carlsbad A tabular summary of potential impacts to structures and utilities at the proposed North Carlsbad beach receiver site is depicted in Section 3.8 (refer to Figure 3-12). 4.8.2.1 Access Stairs As discussed in Section 3.8, public access stairs are located off of Ocean Ave. In addition, several private residential properties have private stairways for beach access, 211603000 4-45 several of which reach the beach surface. All other stairways end approximately 1 m (3 ft) above the beach surface. Although implementation of the proposed action would raise the beach surface and cover the bottom portion of all stairways with sand, beach access would not be restricted. Therefore, adverse impacts to access stairs would not occur upon implementation of the proposed action. 4.8.2.2 Storm Drains A drainage outlet structure is located adjacent to the bottom of the public access stairway off of Ocean Avenue, with two storm drain outlets located approximately 1.2 m (4 ft) above the existing beach surface at the base of the stairs. The top of the proposed sand fill would lie approximately 2.9 m (6 ft) above the existing surface. Potential impacts could occur if beach replenishment activities blocked the opening of the drains and interrupted service. However, implementation of the proposed action would require storm drain discharge flow paths to remain unobstructed; therefore, significant impacts to storm drains would not occur. 4.8.23 Sea Walls Several properties along this stretch of beach have sea walls. Although weep holes would be covered upon implementation of the proposed project, the majority of sea wall tops would not be covered. Several properties have terraced sea walls and landscaping; the lower terraces of which would be covered by the sand fill. As additional sand fill would stabilize the shoreline and protect against erosion, implementation of the proposed action would not significantly impact sea walls in the vicinity of the North Carlsbad receiver site. 4.8.3 South Carlsbad A tabular summary of potential impacts to structures at the proposed South Carlsbad receiver site is depicted in Section 3.8 (refer to Figure 3-13). 4.8.3.1 Access Stairs Four sets of public access stairways are located within the vicinity of the proposed receiver site, stairway base elevations ranging from 1.5 m to 2.6 m (5 ft to 9 ft). In 4-46 211603000 addition, five lifeguard towers are located onsite with base elevations ranging from 1.7 m to 3.6 m (6 ft to 12 ft). The proposed action would cover the bottom portion of the stairways and lifeguard towers with fill, which would tend to stabilize the stairways and structures. As beach access would not be affected by implementation of the proposed action, no impacts to stairways or structures would occur. 4.8.4 Encinitas A tabular summary of potential impacts to structures at the proposed Encinitas receiver site is depicted in Section 3.8 (refer to Figure 3-14). 4.8.4.1 Access Stairs Public and private access stairways are located within the vicinity of the proposed receiver site, stairway base elevations ranging from 0.5 m to 3.5 m (1.6 to 11.5 ft). The proposed action would cover the bottom portion of the stairways with fill, which would tend to stabilize the stairways and structures. As beach access would not be affected by implementation of the proposed action, no impacts to access stairways would occur. 4.8.4.2 Storm Drains Storm drain pipes are located at the end of B Street at Moonlight State Beach and include one 91-cm-dia (36-in-dia) and four 152-cm-dia (60-in-dia) pipes. The City of Encinitas has excavated a few meters around the outlets to expose the pipes and allow proper drainage flow. The invert elevations of these storm drain outlets are approximately +1.5 m (+5 ft) MSL, which is 0.2 m (0.6 ft) below the top of the proposed beach fill. Low drainage flow typically seeps under any sand or cobble that has accrued over the outlet at these locations. During heavy drainage discharge, the flow creates its own path to the ocean. According to the City of Encinitas, this process is acceptable and would continue at these locations subsequent to sand placement (FRH 1997). Therefore, adverse impacts to storm drain outlets in the vicinity of the Encinitas receiver beach would not occur upon implementation of the proposed action. 211603000 4-47 4.8.43 Sea Walls Elevations of the lowest exposed vertical portions of sea walls in the vicinity of the receiver site range from 0 to 2 m (0 to 6.6 ft). Portions of the sea walls would be covered by the proposed fill. However, as additional sand fill would stabilize the shoreline and protect against erosion, no adverse conditions would occur upon implementation of the proposed action. 4.8.5 Torrey Pines As structures or utilities do not exist within the vicinity of the proposed project site, no impacts would occur upon implementation of the proposed action. 4.8.6 Buccaneer Beach/South Carlsbad Alternative No structures or utilities are identified in the vicinity of the South Carlsbad receiver area; therefore, no impacts would occur. A tabular summary of potential impacts at the Buccaneer Beach alternative receiver beach is depicted in Section 3.8 (refer to Figure 3-15). 4.8.6.1 Access Stairs A public access stairway is located at Whaley Street hi the vicinity of the Buccaneer Beach alternative site. The bottom of the stairway is located approximately 2.0 m (6.6 ft) above MSL. The bottom of the stairway would be covered by approximately 0.9 m (3 ft) of proposed beach fill. As public access to the beach via this stairway would not be affected, significant impacts would not occur upon implementation of the proposed action. 4.9 NOISE 4.9.1 Approach to Analysis Significance criteria to determine noise impacts are based on whether any of the following conditions apply: 4-48 211603000 1. The proposed action creates a projected sound level in excess of set construction noise zoning standards; or, 2. The proposed action's operational schedule is in violation of local construction noise standards; or, 3. Site-specific noise levels (e.g., on the beach) created by the proposed action are in excess of current ambient levels. 4. The proposed action complies with local noise ordinances. Table 4-1 identifies predicted sound levels at each receptor and indicates the presence of possible noise impacts based upon the above criteria: C = construction noise level violation; 0 = construction noise ordinance violation; and A = levels generated are hi excess of existing ambient levels. Impact assessment is based upon sound level data of similar equipment (Ogden 1997), and known distances from individual noise sources to their respective receptor points (i.e., residential and/or inhabited structures). 4.9.2 North Carlsbad Onshore beach replenishment activities would use an offshore hopper dredge as the sediment transport vessel. The sand would be mixed with sea water to form a slurry, which would be pumped through a nozzle onto the receiver beach. The sand would then be moved and leveled out using small diesel dozers. In addition, diesel trucks could be required to move sand from one point to another. Any final grooming of the beach would be completed using a cattail assembly behind the dozers, as described above. Operation of the slurry pump onboard the hopper dredge would be inaudible at any of the sensitive receptors examined. Based on the noise analysis conducted for the Homeporting EIS, the diesel dozers would exceed ambient noise levels (50 to 70 dBA) within a certain distance from the receptor, as indicated in Table 4-1. At night, noise from implementation of the proposed action would be more audible and possibly intrusive to nearby sensitive receptors as ambient noise levels are typically lower (at or less than the Lmin values shown hi Section 3.9). Operation of the dozers and cattail 24 hours a day would exceed the City's construction noise ordinance from both operational (time usage) and sound exposure considerations (see Section 3.9). However, the City of Carlsbad has indicated that the proposed North Carlsbad receiver site is held under private property ownership with easements granted to the State Lands Commission below the established high tide line for public access. 211603000 4-49 Table 4-1 EXPECTED NOISE IMPACTS DUE TO REPLENISHMENT ACTIVITIES Beach Site/Equipment North Carlsbad Slurry Pump Diesel Dozer/Cattail South Carlsbad Slurry Pump Diesel Dozer/Cattail Encinitas Slurry Pump Diesel Dozer/Cattail Torrey Pines Slurry Pump Diesel Dozer/Cattail Buccaneer Beach Slurry Pump Diesel Dozer/Cattail Source Level @ 50 Feet 70dBA SOdBA 70dBA SOdBA 70dBA 80dBA 70dBA SOdBA 70dBA SOdBA Slant Distance to Nearest Receptors 1600.0 ft 51.0ft 1601.0ft 78.1ft 1601.0ft 78.1ft 1602.0ft 125.0 ft 1600.0ft 51.0ft Attenuation Due to Topographic Slant Attenuation Distance 30.1 dB 0.2 dB 30.1 dB 3.9 dB 30.1 dB 3.9 dB 30.1 dB 8.0 dB 30.1 dB 0.2 dB 4.9 dB 5.7 dB 4.9 dB 15.1 dB 4.9 dB 15.1 dB 5.4 dB 12.9 dB 4.9 dB 5.7 dB Notes: 1 . Source levels based upon best available data (Ogden 1995, 1997). 2. Slant distance attenuation is based upon the attenuation due to the Level @ Nearest Receptors 35dBA 74dBA 35dBA 61dBA 35dBA 61dBA 35dBA 59dBA 35dBA 74dBA Impact and Type - C,A - C o c,o - C o 0,A closest calculated slant 4. 5. range from the receptor to the source (i.e., (DH2 + DV2)1/2>, DH = minimum horizontal distance, DV = minimum vertical distance) plus the Fresnel (barrier) attenuation due to intervening topography. This is calculated as a point source at a rate of 6 dB/DD. Reference distance taken at 50 feet from source. Topographic attenuation is calculated as being the Fresnel (diffractive barrier) attenuation due to intervening topography. Source modeled as an elevated point source (at 5 feet) at 250 hertz. Receptor setback from topography was 10 feet. Minimum allowable attenuation level set at 3.OdB. Level at nearest receptors is equal to source level minus the slant and topographic attenuation. Values rounded to nearest decibel. Impact Classification: C = construction noise level violation, O = construction noise ordinance violation, and A = levels generated are in excess of existing ambient levels. A dashed (-) entry indicates the absence of a noise violation based upon the analysis. All sound levels given in dBA. All distances given in feet. 4-50 21J603000 Therefore, the City of Carlsbad, through the City's Municipal Code, has no jurisdiction over the North Carlsbad receiver site. The North Carlsbad site would fall under the jurisdiction of the State of California. Since the State currently has no mechanism for issuance of a noise variance, and since the noise would be of a short duration, the State of California (Dupree 1997) has deemed that operations due to beach replenishment would have an adverse but insignificant impact. The California Department of Health Services has requested that all available feasible engineering controls be employed to minimize beach construction noise levels, especially during evening and nighttime hours. 4.9.3 South Carlsbad Operations at the South Carlsbad receiver site were found to produce noise levels in excess of the established limits set by the State of California. This is especially true for nighttime activities associated with operation of the dozers and cattail 24 hours a day. Since the State currently has no mechanism for issuance of a noise variance, and since the noise would be of a short duration, the State of California (Dupree 1997) has deemed that operations due to beach replenishment would have an adverse but insignificant impact. The California Department of Health Services has requested that all available feasible engineering controls be employed to minimize beach construction noise levels, especially during evening and nighttime hours. 4.9.4 Encinitas Operations at the Encinitas receiver site would be identical to the above sites. Both construction noise levels and operational noise impacts would be expected, due to nighttime activities associated with project operations. However, the proposed operations are considered exempt from the City's Noise Abatement Ordinance. The exemption was granted under Municipal Code Section 9.32.417(c), "Federal or State preempted activities." Therefore, the Navy can conclude that noise impacts would not be significant at the Encinitas receiver site. 211603000 4-51 4.9.5 Torrey Pines Operations at the northern Torrey Pines receiver site were found to produce noise levels in excess of the established limits set by the City of Del Mar. A variance to the local noise ordinance would be required in order to operate at night. The proposed action was able to qualify for and has obtained a variation to Chapter 9.20 of the Del Mar Municipal Code (Resolution 97-22, May 19, 1997), which brings it into compliance with the City's noise regulations. Therefore, the Navy is able to conclude that noise impacts would not be significant. There were no identified sensitive receptors at the southern Torrey Pines receiver site, therefore, no significant impacts would be expected to occur upon implementation of the proposed action. 4.9.6 Buccaneer Beach(City of Oceanside)/South Carlsbad Alternative Operations at the Buccaneer Beach Alternative receiver site would be identical to the above sites. Both construction noise level and operational noise impacts would be expected to occur due to nighttime implementation of project construction activities. A variance to the local noise ordinance would be required in order to operate at night. The proposed action was able to qualify for and has obtained a variation to Chapter 38 of the City of Oceanside's Noise Ordinance (Resolution R97-081, May 21,1997), which brings it into compliance with the City's ordinance. Therefore, the Navy is able to conclude that noise impacts would not be significant should the Buccaneer Beach alternative site receive fill. Noise impacts at the South Carlsbad alternative receiver beach are described hi Section 4.9.3. 4-52 211603000 SECTION 5 CUMULATIVE IMPACTS 5.1 CUMULATIVE PROJECTS NEPA requires an analysis of incremental effects of an action that are cumulatively considered when viewed in connection with closely related present, planned, or reasonably foreseeable future actions. In general, the effects of a particular action or group of actions would be considered cumulative impacts under the following conditions: • effects of several actions occur in a common location; • effects are not localized (i.e., can contribute to effects of an action hi a different location); effects on a particular resource are similar hi nature (i.e., affects the same specific element of a resource); and • effects are long term (short-term impacts tend to dissipate over time and cease to contribute to cumulative impacts). Cumulative projects consist of other beach replenishment or beach nourishment projects that are ongoing or are planned to occur in northern San Diego County from Oceanside south to Torrey Pines State Beach (Figure 5-1). Cumulative projects are identified below: A. Oceanside Harbor Dredging at Oceanside Harbor has been ongoing. The harbor is typically dredged semiannually for maintenance purposes. In 1996, approximately 110,000 m3 (140,000 cy) of dredged material was placed hi the nearshore zone hi Oceanside. In 1997, approximately 175,000 m3 (225,000 cy) is expected to be placed on beaches in Oceanside. B. Marine Corps Santa Margarita Desiltation The U.S. Marine Corps at Camp Pendleton dredges areas of the Santa Margarita River to maintain the river channel and remove built-up sediment. Approximately 30,000 m3 (40,000 cy) of sediment was placed hi the nearshore zone hi South Oceanside. This project was completed in 1994. Additional maintenance dredging of the Santa Margarita River channel is planned hi 1997-98. 211603000 5-1 o/ /CAMP PENDLETON FALLBROOK WARNER, SPRINGS Lake Henshaw -w £\\ OGE ANSIDE .1 3t\V —V.STA , CARLSBAD SAN MARCOS Lake)Hodges IA BEACH Os) & Wohlford .ESCONDIDO Lake Sutherland SANTAYSABEL IRANCHO T BERNARDO RAMONA _ San Vicente "POWAY \Reseivoir SANTEE/ rELC]jkJON |54l . ElCapten' Reservoir ALPINE *—+•Loveland Reservoir Barren Lake LEGEND COMPLETED PROJECTS ONGOING/PERIODIC PROJECT 1,000's OF CUBIC YDS.OF SAND IMPERIAL BEACH f SOURCE: San Diego AssocJafon of Govemments DIEGO CHL\A VISTA. 4YSIDRO ^^ V TIJUANA JAMUL .DULZURA FIGURE Cumulative Projects 5-1 BENVIR ASS'MT(ENV)\Environ AssessmentXReceiver Beach EA\SD County Map C. Oceanside Beach Nourishment The City of Oceanside and the La Paz County Landfill in Arizona have developed a program to trade desert sand from the landfill for trash from the City of Oceanside. Trucks will haul trash from Oceanside to La Paz, and return with sand. Approximately 8,000 m3 (10,500 cy) will be deposited as beach nourishment on various Oceanside city beaches. D. Agua Hedionda Lagoon A phased maintenance dredging project began in Agua Hedionda Lagoon in 1995. Phases II and III were completed in 1996, which resulted in the placement of over 150,000m3 (193,000 cy) of dredged material on beaches north of the inlet jetty and south of the outlet jetty in Carlsbad. E. Batiquitos Lagoon Efforts to restore Batiquitos Lagoon have resulted in dredging of approximately 1,375,000 m3 (1,800,000 cy) of sediment from the lagoon. A beach replenishment project completed in 1996 placed sediments dredged from the lagoon on beaches in north Carlsbad, south of Agua Hedionda Lagoon, and in south Carlsbad, north of Batiquitos Lagoon. To maintain areas of the lagoon, an ongoing dredging project is planned. F. Moonlight Beach The Moonlight State Beach project is an ongoing beach replenishment plan that places approximately 770 m3 (1,000 cy) of sediment on the beach in Encinitas on a yearly basis. G. San Elijo Lagoon Mouth Opening The San Elijo Lagoon Mouth Opening project is an annual maintenance dredging project. In 1996, approximately 4,500 m3 (6,000 cy) of sand and cobble was placed on the beach 300 yards south of the lagoon mouth in Encinitas. In 1997, another 4,500 m3 (6,000 cy) of sand and cobble is expected to be placed on the beach south of the lagoon. 211603000 5-3 H. Lomas Santa Fe Drive Grade Separation The Lomas Santa Fe Drive Grade Separation project is expected to begin in early 1997 and conclude in 1998. The project is expected to result in the placement of 33,000 m3 (40,000 cy) of sand at Fletcher Cove in Solana Beach. None of these beach fills (A through H) would have significant cumulative impact with this study's beach fills. Even the largest of the three projects, 33,000 m3 from the Loma Santa Fe grade separation, is less than a 10 percent to the Solana Beach fills; or in other words, about 150m (500 ft) of additional beach fill length. This addition does not significantly affect the extent of sand movement. I. U.S. Navy Homeporting The Navy plans to place approximately 5.4 million m3 (7 million cy) of dredged sediment on several beaches in northern San Diego County as part of the CVN homeporting project in San Diego Bay. In addition to the four receiver beaches (North and South Carlsbad, Encinitas, and Torrey Pines) identified in the proposed action, the Navy plans to place sediment on beaches hi South Oceanside and Solana Beach. The South Oceanside and Solana Beach sites were analyzed as part of a previous Phase I Environmental Assessment (U.S. Navy 1997). Although the model results (FRH 1997) indicate that the Homeporting beach fill at South Carlsbad, Solona Beach, and Torrey Pines would not cause cumulative effects due to their distance separation and shoreline configuration, placement of the three beach fills at South Oceanside (Phase I site), Buccaneer Beach (Alternative Phase II site), and North Carlsbad (Phase II site) would result in interactive effects due to multiple beach fills. The model results indicate that: a longshore spread of beach fill sand would occur during the simulation period (Figure 5-2). The shoreline position changes at the San Luis Rey River, Loma Alta Creek and Buena Vista Lagoon inlets include the widening of the existing natural berm and beach. No buildup of sediment beyond the natural berm height would be anticipated to result at the San Luis Rey River and Loma Alta Creek inlets. Continued maintenance of the Buena Vista Lagoon weir would be required. 5-4 211603000 SOUTH OCEANSIDE- BEACH FILL BUCCANEER- BEACH FILL -NORTH CARLSBAD BEACH FILL -APPROXIMATE SHORELINE AT 12 MONTHS AFTER PLACEMENT nnFA jsinp HAHHOR s IIITH .IPTTV Pre-Fill 3 months 6 months 12 months 1000 2000 3000 4000 5000 6000 Shoreline Station (m) 7000 8000 9000 10000 FIGURE Cumulative Mean Sea Level Shoreline Response, South Oceanside to North Carlsbad 5-2 BENVIR ASS'MT(ENV)\Envlron Assessment\Recelver Beach EA\RB-Format.FH5 • Cumulative impacts to surfing would not be expected to vary from those discussed earlier for individual beach fills. • Scarping would not be anticipated to increase due to cumulative impacts since beach fills are not being placed on top of one another with resulting higher berms. Cumulative impacts due to turbidity would not increase above those discussed earlier for individual beach fills. • Cumulative impacts to coastal wetlands would not be expected beyond those discussed for the individual beach fills. Recreation and shoreline protection would be significantly improved in the area from Wisconsin Street to Buena Vista Lagoon. 5.2 CUMULATIVE ENVIRONMENTAL EFFECTS 5.2.1 Geology and Soils Because the Oceanside littoral cell has been eroding and a reduction of natural sources for beach replenishment is occurring, implementation of the proposed action would be a beneficial impact and would cumulatively contribute to the reduction of erosion at the identified beach sites. Therefore, implementation of the proposed action would be a cumulatively beneficial impact to geology and soils. Figure 5-2 illustrates the predicted cumulative mean sea level shoreline responses to the three beach fills at South Oceanside, Buccaneer Beach, and North Carlsbad. Results of the modeling (FRH 1997) indicate a longshore spread of beach fill sand during the 12-month simulation period. Table 5-1 shows the results for the three beach fills modeled independently compared to the cumulative effects of the three beach fills modeled together. These results indicate that, in general, there would be a net shoreline accretion north of Oak Avenue due to simultaneous beach fill construction and no net shoreline change south of Oak Avenue or at Agua Hedionda Lagoon inlet. The cumulative shoreline position changes at the San Luis Rey River, Loma Alta Creek, and 5-6 211603000 Table 5-1 COMPARISON OF CUMULATIVE IMPACTS TO INDIVIDUAL BEACH FILLS Shoreline Location San Luis Rey River Wisconsin Avenue Loma Alta Creek Buena Vista Lagoon Oak Avenue Agua Hedionda Lagoon Individual 12 South Oceanside +10 +19 +12 0 0 0 Shoreline Position in Months (m) Buccaneer Beach +14 -2 +18 +3 0 0 North Carlsbad 0 0 0 +19 0 0 Cumulative Shoreline Position (m) +15 +29 +34 +29 +1 0 Effect in 12 Change from Max. (m) +1 +10 +16 +10 +1 0 Months Percent Change (%) +2 +22 +5 +17 +1 0 Notes: 1. "+" indicates accretion of shoreline position 2. Shoreline position represent Mean Sea Level (MSL) Shoreline 3. Cumulative impacts based on continuous beach fill operations from north to south 4. % indicates the increase of beach width from width surveyed in March 1996 211603000 5-7 Buena Vista Lagoon inlets represent a widening of the existing natural berm and beach of approximately 2 percent, 5 percent; and 17 percent, respectively. Because the net cumulative shoreline change at the San Luis Rey River inlet would only be about 1 m (3 ft), no buildup of sediment beyond the natural berm height is anticipated. No additional impacts are expected beyond those discussed for the South Oceanside Beach fill (Phase IEA; U.S. Navy 1997) The modeling results indicate that the MSL beach width at Loma Alta Creek would increase approximately 34 m (112 ft) due to cumulative impacts; which is approximately 16 m (57 ft) more than any individual beach fill alone. However, none of the fills are anticipated to cause any adverse impacts to the Loma Alta Creek inlet since the City of Oceanside currently builds a sand berm in front of the creek preventing flow through the inlet between Memorial Day and Labor Day. Also, during the rainy season, the city excavates a temporary channel to facilitate stream flow to the ocean. The modeling results for Buena Vista Lagoon indicate that the MSL beach width would increase approximately 29 m (95 ft) due to cumulative impacts; which is approximately 10 m (33 ft) more than any individual beach fill alone. The existing weir at the outlet to the lagoon is at an elevation of +1.82 m (6 ft) MSL and the fill berm elevation would range from +1.7 to +2.9 m (+5.6 to +9.5 ft). Since this is the same berm elevation predicted for individual beach fill, no additional cumulative impacts would be anticipated. Continued maintenance of the flow path seaward of the weir would be required. 5.2.2 Coastal Wetlands Dredge and discharge operations associated with the proposed action together with cumulative projects in the area are being implemented for the purpose of beach enhancement and replenishment. No cumulative impacts to coastal wetlands are expected beyond those discussed for the individual sites. Furthermore, inlet maintenance programs are currently in place at the San Luis Rey River, Loma Alta Creek, Buena Vista Lagoon, Agua Hedionda Lagoon, Encinas Creek, Batiquitos Lagoon, San Elijo Lagoon, San Dieguito Lagoon, and Los Penasquitos Lagoon. Table 5-2 depicts inlet maintenance responsibilities. These programs ensure that no significant impacts occur to the value and function of coastal wetlands. No additional impacts would be expected beyond those 5-8 211603000 Table 5-2 INLET MAINTENANCE RESPONSIBILITY Lagoon / Inlet Inlet Maintenance Responsibility San Luis Rey River Loma Alta Creek Buena Vista Lagoon Agua Hedionda Lagoon Encinas Creek Batiquitos Lagoon San Elijo Lagoon San Dieguito Lagoon Los Penasquitos Lagoon City ofOceanside City ofOceanside City ofOceanside / City of Carlsbad San Diego Gas & Electric City of Carlsbad / California State Department of Parks and Recreation U.S. Fish and Wildlife Service / National Marine Fisheries Service / California State Lands Commission / California Department of Fish and Game / Port of Los Angeles / City of Carlsbad California Department of Fish and Game / San Diego County Department of Parks and Recreation / California State Department of Parks and Recreation City of Del Mar/22nd Agricultural District Los Penasquitos Lagoon Foundation / California Department of Fish and Game / California State Department of Parks and Recreation Source: San Diego Association of Governments 1997 211603000 5-9 discussed for the individual beach fills. Therefore, no significant cumulative impacts would occur to coastal wetlands as a result of implementation of the proposed action. 5.2.3 Water Resources The proposed action would be implemented in accordance with permit specifications as provided by the ACOE, EPA, and the RWQCB. Permit specifications include measures intended to reduce water quality/hydrological impacts anticipated in beach replenishment projects. All identified cumulative projects are required to comply with such guidelines. Therefore, an increase in turbidity anticipated with the proposed action would not be expected to degrade water quality in the nearshore environment on a cumulative level. 5.2.4 Biology Implementation of the proposed action would be expected to cause short-term cumulative impacts to nonsensitive species (mobile and nonmobile invertebrates) that inhabit the intertidal and surf zone of the sandy beaches where onshore beach replenishment activities would occur. However, upon completion of replenishment activities, nonsensitive species would repopulate in the affected areas. No cumulative impacts would be expected to occur to sensitive habitats (reefs) or species (grunion, surfgrass, or giant kelp). Strict engineering controls would ensure that beach replenishment is limited to areas that would not impact sensitive habitats and species. No impacts to grunion would be anticipated to occur, due to implementation of a monitoring program that would halt replenishment activities if grunion were observed spawning. Therefore, no cumulative impacts would be expected to occur to biological resources. 5.2.5 Land Use and Recreation Beach replenishment activities would be compatible with existing coastal land uses. Additionally, no inconsistencies with federal, state, or local land use plans were identified. Therefore, no cumulative land use impacts would occur. Recreational activities would be temporarily redistributed to other local beach areas upon implementation of the proposed project. However, beach areas in the vicinity of the receiver sites have no maximum capacity and, therefore, are capable of accommodating additional recreational users. Because these measures would only be implemented on a 5-10 211603000 short-term basis, no cumulative recreational impacts would occur. Scarping is not expected to increase since beach fills are not being placed on tap of one another with resulting higher berms. 5.2.6 Safety and Environmental Health Safety measures associated with the proposed action include onshore and offshore closure to public access, safety buffer zones, onshore barricades, and safety personnel as necessary. Because these safety measures would only be utilized on a short-term basis for the length of beach replenishment activities, no cumulative impacts to safety and environmental health would occur. 5.2.7 Aesthetics Cumulative visual impacts are dependent on the scenic quality of the region and the type of proposed project. The coastal region of San Diego County is considered to be highly scenic. Sand placement activities along the proposed receiver beach sites would result in short-term visual impacts that would cease at the end of construction activities. The proposed action would be considered to have long-term beneficial visual impacts, as beach replenishment would widen San Diego beaches currently affected by erosion and improve coastal views. Therefore, implementation of the proposed action would have cumulative beneficial visual impacts along the coast. 5.2.8 Structures and Utilities Regional demand for existing utility services such as water, sewer, gas and electric, solid waste and wastewater would not be cumulatively increased. Short-term cumulative interruption of services would be avoided by project-by-project monitoring efforts. It is not anticipated that any long-term cumulative disruption impacts would occur. 5.2.9 Noise Construction activities associated with the proposed action would likely generate a change to noise levels in the vicinity of the receiver beaches for the duration of the project. Noise changes at the receiver beaches would not contribute to cumulative noise impacts due to the distance between the proposed receiver beaches. In addition, beach 211603000 5-11 replenishment activities would not likely occur concurrently with other projects similar in nature. Increases in noise levels would only be short term and would return to existing levels upon completion of beach replenishment activities. Therefore, no cumulative noise impacts would occur upon implementation of the proposed action. 5-12 211603000 SECTION 6 IRREVERSIBLE OR IRRETRIEVABLE COMMITMENTS OF RESOURCES Resources that are irreversibly or irretrievably committed to a project are those that are typically used on a long-term or permanent basis; however, some are considered short-term resources that cannot be recovered and are thus also considered irretrievable. These resources may include the use of nonrenewable resources such as fuel, wood, or other natural or cultural resources. Human labor is also considered a nonretrievable resource because labor used for the proposed action would not be used for other purposes. The unavoidable destruction of natural resources that limit the range of potential uses of that particular environment would also be considered an irreversible or irretrievable commitment of resources. The proposed beach replenishment activities at North Carlsbad, South Carlsbad, Encinitas, and Torrey Pines would result in the placement of approximately 2,209,610 m3 (2,850,400 cy) of dredged beach-compatible fill material. The dredged material has already been committed as part of the Homeporting project; thus, the need for a disposal site (or sites) is eminent. The proposed action would result in the consumptive use of nonrenewable energy sources and labor required to operate barges, trucks, pumping equipment, and grading equipment. These commitments of resources could have otherwise been applied to projects other than the proposed action. However, the proposed action would not result in the use of a substantial amount of resources and would be short-term in nature. Additionally, no natural resources would be permanently destroyed and beach replenishment would be considered a beneficial use of the dredged material. 211603000 6-1 This Page Intentionally Left Blank 6-2 211603000 SECTION 7 THE RELATIONSHIP BETWEEN LOCAL SHORT-TERM USE OF THE HUMAN ENVIRONMENT AND THE MAINTENANCE AND ENHANCEMENT OF LONG-TERM PRODUCTIVITY The objective of the proposed action is to provide a beneficial use for the disposal of dredged materials, replenish sand at receiver beaches to widen existing beaches and reduce erosion potential, and increase recreational opportunities at the four receiver beach sites for long-term use. Disposal of beach-compatible dredged material on the receiver beaches is considered a beneficial use of dredged materials, and would support SANDAG's Shoreline Preservation Strategy; policies contained in the Carlsbad, Encinitas, and San Diego Coastal State Park System General Plans; and the project objectives. The proposed action would help to preserve the long-term use of the receiver beaches as recreational resources. Implementation of the proposed action would not result in any environmental impacts that would significantly narrow the range of beneficial uses of the environment or pose long-term risks to health, safety, or the general welfare of the public communities surrounding the receiver beaches. Rather, the project would provide for future beneficial beach resources (e.g., recreation activities). 211603000 7-1 This Page Intentionally Left Blank 7-2 211603000 SECTION 8 LIST OF PREPARERS This Environmental Assessment was prepared for, and under the direction of, the U.S. Department of the Navy, by Ogden Environmental and Energy Services Co., Inc. and Frederic R. Harris, Inc. Members of the professional staff are listed below. Ogden Environmental and Energy Services Co., Inc. Project Management Paul Amberg, Project Manager B.A. Environmental Studies Technical Analysts John Conley B.A. Geography Howard Cumberland M.S. Biology Lawrence Honma B.S. Wildlife and Fisheries Biology M.S. Marine Sciences Karen Ames B.S. Public and Environmental Affairs Sandy Fleming B.A. Political Science Rick Tavares M.S. Mechanical Engineering M.S. Structural Engineering 211603000 8-1 Geographic Information Systems Pat Atchison, GIS Manager M.A. Geography Andrew Hanes B.S. Geography Jay Tessier B.S. Geology U.S. Navy, Southwest Division Patrick McCay Environmental Planner Mitchell Perdue Soils Conservationist 8-2 211603000 SECTION 9 LIST OF AGENCIES AND PERSONS CONSULTED U.S. Fish and Wildlife Service Gail C. Kobetich, Field Supervisor Doreen Stadtlander, Fish and Wildlife Biologist National Marine Fisheries Service Robert Hoffman, Fisheries Biologist California Coastal Commission Sherilyn Sarb, Supervisor of Permits San Diego Association of Governments Steve Sachs, Senior Regional Planner California State Department of Parks and Recreation Ed Navarro, District Supervisor Dennis Stoufer, Lifeguard Supervisor II CityofOceanside Ray Duncan, Lifeguard Manager City of Encinitas Chris Miller, Planning Technician Tom Buckner, Lifeguard Supervisor 211603000 9-1 This Page Intentionally Left Blank 9-2 211603000 SECTION 10 REFERENCES Barilotti, D.C. 1983. Measurements needed to determine the ecologically important effects of discharged wastes in kelp bed habitats. In: W. Bascom (ed.). The Effects of Waste Disposal on Kelp Communities. Southern California Coastal Waters Research Project, Long Beach, CA. pp. 163-180. Barnard, J.L. 1963. Relationship of Benthic Amphipoa to Invertebrate Communities of Inshore Sublittoral Sands of Southern California. Pacific Naturalist 3:439-467. Butler Roach Group. 1995. Evaluation of Potential Impacts to Marine Biota from the Beach Replenishment Component of the Proposed Lomas Santa Fe Drive Grade Separation Project. Prepared by MEC Analytical Systems, Inc. April. Bradshaw, J., B. Browning, K. Smith, J. Speth, and E. Fullerton. 1976. The Natural Resources for Agua Hedionda Lagoon. Technical Report prepared for the U.S. Fish and Wildlife Service (Portland, Oregon) by University of San Diego (San Diego, California). 109pp. California Chamber of Commerce. 1995. California Environmental Compliance Handbook. California Coastal Commission. 1995. Coastal Consistency Determination for the Development of Facilities in San Diego to Support the Homeporting of One NIMITZ Class Aircraft Carrier. May. California Department of Parks and Recreation. 1984. San Diego Coastal State Park System General Plan. Volume 3: South Carlsbad State Beach. July 1984. California Department of Parks and Recreation. 1984. San Diego Coastal State Park System General Plan. Volume 8: Torrey Pines State Beach and State Reserve. July 1984. California Regional Water Quality Control Board (RWQCB). 1995. Waste Discharge Requirements for the U.S. Navy Dredge and Fill Activities, Homeporting Project, San Diego County. Order No. 95-118. December. Carlsbad Opportunistic Sand Project. 1995. Opportunistic Beach Fill Practice to Reduce Impacts. Prepared by Moffatt & Nichol, Engineers. March. City of Carlsbad. 1996. City of Carlsbad Local Coastal Program. Revised 1996. City of Carlsbad. 1994. Carlsbad General Plan. Adopted September 6,1994. 2J1603000 10-1 City of Del Mar. 1985. City of Del Mar Land Use Element. City of Encinitas. 1989. City of Encinitas General Plan. Adopted March 29, 1989. City of Oceanside. 1986. Land Use Element. Adopted September, updated January 1989. City of Oceanside. 1985. Local Coastal Program, Land Use Plan. 10 July. City of Oceanside. 1974. Oceanside General Plan. Resolution No. 74-226. 27 November. City of San Diego. 1989. City of San Diego Progress Guide and General Plan. Updated June 1989. County of San Diego Department of Parks and Recreation. 1995. San Elijo Lagoon Area Enhancement Plan Draft. August. Cross, J.N. and L.G. Allen. 1990. Fishes of the Southern California Bight. In Dailey, M.D., D.J. Reish, and J.W. Anderson. Ecology of the Southern California Bight: A Synthesis and Interpretation. U.S. Department of the Interior, Minerals Management Service. Devinny, J.S. and L.A. Volse. 1978. Effects of sediments on the development of Macrocystis pyrifera gametophytes. Marine Biology 48:343-348. Duncan, Ray. 1997. Lifeguard Manager, City of Oceanside. Personal communication, 11 March. Dupree, Russ. 1997. State of California Office of Noise Control. Personal Communication with Ogden. April 15. Environmental Protection Agency (EPA). 1986. Environmental Assessment for Relocation of the Naval Command, Control and Ocean Surveillance Center/Research, Development, Test, and Evaluation Detachment Located at the Marine Corps Ah- Station Kaneohe, Hawaii, to NCCOSC RTD&E, San Diego, California, U.S. Department of the Navy. November 1992. Frederic R. Harris, Inc. (FRH). 1997. Beach Sand Transport and Sedimentation Report, Phase I and II. Prepared for U.S. Department of the Navy, Southwest Division. Frederic R. Harris, Inc. (FRH). 1996. Kelp Bed Locations Along the San Diego County Coast. Prepared by H. Elwany, L. H. Dean, K. Zabloudil, B. Van Wagenen, and R. Flick. 10 September. 10-2 211603000 Gerard, V.A. 1984. The light environment in a giant kelp forest: Influence of Macrocystsis pyrifera on spatial and temporal variability. Marine Biology (Berlin) 84:189-195. Kobetich, Gail C. 1997. Field Supervisor, U.S. Fish and Wildlife Service. Letter to Army Corps of Engineers, Los Angeles District. 5 March. La Paz County Landfill. 1996. Oceanside Beach Nourishment Demonstration Project. Prepared by H. Elwany, J. Nichols, W. Gayman, and R. Flick. 7 July. Lobban, C.S., P.J. Harrison, and M.J. Duncan. 1985. The physiological ecology of seaweeds. Cambridge University Press, Cambridge. 242pp. MEC Analytical Systems, Inc. 1993. San Dieguito Lagoon Restoration Project Regional Coastal Lagoon Resources Summary. Draft Technical Memorandum. Prepared for Southern California Edison. July. Moffat and Nichols, Engineers. 1983. Experimental Sand Bypass System at Oceanside Harbor, California. Phase I Report: Data Collection and Analysis. Morin, J.G., J.E. Kastendiek, A. Harrington, and N. Davis. 1985. Organization and patterns of interactions in a subtidal sand community on an exposed coast. Marine Ecology Progress Series 27:163-185. Morin, J.G., J.E. Kastendiek, A. Harrington, and N.° Davis. 1988. Organisms of a subtidal sand community in Southern California. Bulletins Southern California Academy of Sciences 87:1 -11. Ogden Environmental and Energy Services, Inc. 1997. Construction Reference Noise Level Database. Roswall, Rick. 1997. Lifeguard Services. City of Solana Beach. Personal communication, 11 March. San Diego Association of Governments (SANDAG). 1996. Year End Report to Shoreline Erosion Committee on Opportunistic Sand Projects. 26 November. San Diego Association of Governments (SANDAG). 1993. Shoreline Preservation Strategy for the San Diego Region. July. Sterrett, E.H. and R.E. Flick. 1994. Shoreline Erosion Assessment and Atlas of the San Diego Region, Vol. II. California Department of Boating and Waterways. Sacramento, CA. 211603000 10-3 Stoufer, Dennis. 1997. Lifeguard Supervisor II, California State Department of Parks and Recreation. Personal communication, 12 March. Straughan, D. 1982. Inventory of the natural resources of sandy beaches in Southern California. Allan Hancock Foundation, Los Angeles, CA. 447pp. Thompson, B., J. Dixon, S. Schroeter, D.J. Reish. 1990. Chapter 8 Benthic Invertebrates. In: Dailey, M.D., D.J. Reish, and J.W. Anderson (eds.). 1990. Ecology of the Southern California Bight: A Synthesis and Interpretation. U.S. Department of the Interior Minerals Management Service and Ocean Studies Institute. Thompson, B., J. Dixon, S. Schroeter, and D.J. Reish. 1993. Ecology of the Southern California Bight: A Synthesis and Interpretation. Chapter 8, Benthic Invertebrates. University of California Press. U.S. Army Corps of Engineers (ACOE), Los Angeles District. 1997. Public Notice of Permit Modification for Department of the Army Permit No. 94-20861-DZ. U.S. Army Corps of Engineers (ACOE), Los Angeles District. 1996a. Department of the Army Permit No. 94-20861-DZ. U.S. Army Corps of Engineers (ACOE), Los Angeles District. 1996b. Environmental Evaluation for the Encinitas Shoreline, San Diego County, California. March. U.S. Army Corps of Engineers (ACOE), Los Angeles District. 1994. Final Environmental Assessment for Oceanside Harbor Maintenance Dredging, San Diego County, California. August. U.S. Army Corps of Engineers (ACOE). 1991. Coast of California Storm and Tidal Waves Study. U.S. Army Corps of Engineers (ACOE), Waterways Experiment Station. 1984. Shore Protection Manual. U.S. Department of the Navy, Naval Facilities Engineering Command Southwest Division. 1997a. Environmental Assessment for Beach Replenishment at South Oceanside and Cardiff/Solana Beach, California. Prepared by Ogden Environmental and Energy Services, Inc. April. U.S. Department of the Navy, Naval Facilities Engineering Command Southwest Division. 1997b. Kelp Mapping. Performed by Natural Resources Branch. 10-4 211603000 U.S. Department of the Navy, Naval Facilities Engineering Command Southwest Division. 1996. Distribution of Resuspended Sediment from Dredging of the Navigation Channel - San Diego Bay. August. U.S. Department of the Navy. 1995a. Final Environmental Impact Statement for the Development of Facilities in San Diego/Coronado to Support the Homecoming of One NIMITZ Class Aircraft Carrier. Volumes 1-3. Prepared by Ogden Environmental and Energy Services, Inc. November. U.S. Department of the Navy. 1995b. Record of Decision for the Development of Facilities in San Diego/Coronado, California to Support the Homeporting of One NIMTZ-Class Aircraft Carrier. U.S. Department of the Navy, Naval Facilities Engineering Command Southwest Division. 1995c. Sediment Characterization Report of NIMITZ Class Aircraft Carrier Homeporting Facilities, Naval Air Station North Island. Prepared by Ogden Environmental and Energy Services, Inc. 211603000 10-5 This Page Intentionally Left Blank 10-6 211603000