STAFF REPORT Living with a Rising Bay: Vulnerability and Adaptation in San Francisco Bay and on its Shoreline Approved on October 6, 2011 SAN FRANCISCO BAY CONSERVATION AND DEVELOPMENT COMMISSION 50 California Street, Suite 2600 San Francisco, CA 94111 Information: (415) 352-3600 Fax: (415) 352-3606 Web site: http://www.bcdc.ca.gov TABLE OF CONTENTS ACKNOWLEDGMENTS ................................................................................................................................. v EXECUTIVE SUMMARY ................................................................................................................................. 1 The Vulnerability Assessment ....................................................................................................... 2 1. Shoreline Development ............................................................................................................... 2 2. The Bay .......................................................................................................................................... 5 3. Governance ................................................................................................................................... 6 Adaptation Strategies ...................................................................................................................... 7 Proposed Bay Plan Amendment ............................................................................................... 8 CHAPTER 1. CAUSES OF SEA LEVEL RISE ............................................................................................. 11 The Greenhouse Effect and Global Warming ............................................................................ 11 Emissions Scenarios ......................................................................................................... 12 The California Climate Action Team ............................................................................. 13 Bay Area GHG Contributions ......................................................................................... 15 Sea Level Rise ................................................................................................................................. 17 Ice-Sheet Melting and Uncertainty................................................................................. 19 Sea Level Rise Scenarios ............................................................................................................... 20 Sea Level Rise and Extreme Events ............................................................................... 22 BCDC Policy Analysis ...................................................................................................... 23 Vulnerability Assessment ............................................................................................................. 25 Vulnerability from Subsidence ....................................................................................... 26 Shoreline Protection....................................................................................................................... 41 Summary and Conclusions .......................................................................................................... 44 CHAPTER 2. SHORELINE DEVELOPMENT ............................................................................................... 47 Residential Land Use ..................................................................................................................... 48 Residents with Increased Vulnerability ........................................................................ 50 Schools and Emergency Services .................................................................................... 57 Commercial and Industrial Land Use ......................................................................................... 57 Airports .............................................................................................................................. 57 Ports .................................................................................................................................... 59 Water-Related Industry ................................................................................................... 62 Indirect Effects of Sea Level Rise ................................................................................................. 63 Public Health Impacts of Climate Change ................................................................................. 63 Other Shoreline Land Uses, Infrastructure and Institutions ................................................... 64 Wastewater Treatment Facilities .................................................................................... 64 Flood Control Channels ................................................................................................... 65 Contaminated Lands ........................................................................................................ 65 Pipelines and Transmission Lines .................................................................................. 65 The Regional Transportation Network ....................................................................................... 66 Major Roadways and Highways .................................................................................... 67 i Rail Network ..................................................................................................................... 69 Waterfront Parks and Beaches ..................................................................................................... 71 Public Access Required by BCDC ............................................................................................... 72 Summary and Conclusions .......................................................................................................... 75 CHAPTER 3. THE SAN FRANCISCO BAY ECOSYSTEM .......................................................................... 79 Sea Level Rise in the Bay Ecosystem ........................................................................................... 80 Constraints to Wetland Adaptation ............................................................................... 81 Salinity Change in Tidal and Subtidal Habitats ........................................................... 83 Other Water Quality Impacts ....................................................................................................... 86 Invasive and Migrant Species ...................................................................................................... 87 Threat of Extinction ....................................................................................................................... 88 Shoreline Protection Impacts........................................................................................................ 90 Ecological Consequences of a Tidal Barrage ................................................................ 90 Watershed Land Use ..................................................................................................................... 92 Restoration and Adaptive Management .................................................................................... 93 Suisun Marsh ..................................................................................................................... 95 North Bay ........................................................................................................................... 95 Central Bay ........................................................................................................................ 96 South Bay ..................................................................................................................... 98 Summary and Conclusions ........................................................................................................ 100 CHAPTER 4. GOVERNANCE: WHAT BCDC AND LOCAL JURISDICTIONS CAN DO .......................... 103 The Governance Landscape ....................................................................................................... 103 The Commission’s Jurisdiction and Authority ........................................................................ 106 The Commission’s Jurisdiction ..................................................................................... 107 The Commission’s Permit Authority ........................................................................... 107 Salt Ponds and Managed Wetlands ............................................................................. 108 The 100-Foot Shoreline Band ........................................................................................ 109 Existing Bay Plan Policies Pertaining to Sea Level Rise ............................................ 109 The Public Trust Doctrine and Takings ....................................................................... 110 Needs Assessment for Local Jurisdictions ............................................................................... 112 Statewide Survey ............................................................................................................ 113 Summary and Conclusions ........................................................................................................ 116 CHAPTER 5. ADAPTATION STRATEGIES FOR SAN FRANCISCO BAY AND THE SHORELINE ...... 119 Adaptation Planning Considerations