CITY OF BUENA PARK LOCAL HAZARD MITIGATION PLAN November 2017 This page is deliberately blank LOCAL HAZARD MITIGATION PLAN BASIC PLAN Table of Contents Credits ........................................................................................................................ 5 Part I: BACKGROUND .............................................................................. 7 Executive Summary .................................................................................................. 7 Mitigation Planning Benefits ................................................................................................ 7 Hazards and Land-Use Policy in California ......................................................................... 8 Support for Hazard Mitigation ............................................................................................. 8 How is the Plan Organized? ................................................................................................ 9 City of Buena Park and Hazard Mitigation ..........................................................................10 Mitigation Planning Process ...............................................................................................12 Plan Review .......................................................................................................................12 Plan Adoption ....................................................................................................................13 Plan Approval ....................................................................................................................13 Point of Contact .................................................................................................................13 Plan Maintenance ..............................................................................................................13 Section 1: Introduction ............................................................................................ 15 Why Develop a Mitigation Plan? ........................................................................................15 Why Plan for Hazards? ......................................................................................................16 Hazard Mitigation Legislation .............................................................................................16 State and Federal Support .................................................................................................18 Hazards U.S. – Multi-Hazard .............................................................................................19 Who Does the Mitigation Plan Affect? ................................................................................20 Section 2: Community Profile ................................................................................. 23 Geography and the Environment .......................................................................................23 History ...............................................................................................................................23 Climate ..............................................................................................................................24 Population and Demographics ...........................................................................................25 Employment and Industry ..................................................................................................26 Transportation and Commuting Patterns ............................................................................28 Part II: HAZARD ANALYSIS .................................................................... 31 Section 3: Risk Assessment ................................................................................... 31 What is a Risk Assessment? ..............................................................................................31 Critical and Essential Facilities ...........................................................................................35 Land and Development ......................................................................................................36 Key Focus Areas for Growth ..............................................................................................36 Summary ...........................................................................................................................36 Section 4: Earthquake Hazards .............................................................................. 39 Earthquake Characteristics ................................................................................................39 Measuring and Describing Earthquakes .............................................................................40 Regulatory Background .....................................................................................................42 Historical Earthquakes in Orange County ..........................................................................43 Local Hazard Mitigation Plan | November 22, 2017 Page 1 of 187 LOCAL HAZARD MITIGATION PLAN BASIC PLAN Previous Occurrences of Earthquakes in the City of Buena Park .......................................44 Earthquake Hazard Assessment ........................................................................................44 Impact of Earthquakes in the City of Buena Park ...............................................................47 Earthquake-Related Hazards .............................................................................................48 Risk Analysis .....................................................................................................................57 Community Earthquake Issues ..........................................................................................57 Existing Mitigation Activities ...............................................................................................61 Section 5: Dam Failure Hazards ............................................................................. 65 Dam Failure Risk Factors...................................................................................................65 Flooding Following Dam Failure .........................................................................................67 Severity ..............................................................................................................................68 How Are Inundation Areas Identified? ................................................................................69 Historic Dam Failures in Southern California ......................................................................70 Flood Hazard Assessment .................................................................................................70 Local Conditions ................................................................................................................71 Impact of Dam Failure in Buena Park ................................................................................74 Section 6: Flood Hazards ........................................................................................ 77 Flood Risk Factors .............................................................................................................77 Flood Terminology .............................................................................................................78 Types of Flooding ..............................................................................................................79 Severity ..............................................................................................................................80 How are Flood-Prone Areas Identified? .............................................................................83 Definitions of FEMA Flood Zone Designations ...................................................................84 Flood-Mapping Methods and Techniques ..........................................................................89 Historic Flooding in Southern California .............................................................................89 Previous Occurrences of Flooding in the City of Buena Park .............................................89 Flood Hazard Assessment .................................................................................................91 Local Conditions ................................................................................................................91 Impact of Flooding in Buena Park ......................................................................................92 Section 7: Drought .................................................................................................. 97 Hazard Identification and Risk Assessment .......................................................................97 Previous Occurrences of Drought ....................................................................................100 Impact of Drought on Buena Park ....................................................................................103 PART III: MITIGATION STRATEGIES ................................................... 107 Section 8: Mitigation Strategies ........................................................................... 107 Overview of Mitigation Strategy .......................................................................................107 Planning Approach ..........................................................................................................107