San Diego Gas & Electric Company Wildfire Mitigation Plan February 7, 2020 (Rev 1.) March 2, 2020 Table of Contents Executive Summary .................................................................................................................... viii 1. Persons Responsible for Executing the WMP ........................................................................ 1 1.1. Verification ..................................................................................................................... 3 2. Metrics and Underlying Data ................................................................................................. 4 2.1. Lessons Learned: How Tracking Metrics on the 2019 Plan Has Informed the 2020 Plan ........................................................................................................................ 4 2.2. Recent Performance on Progress Metrics, Last 5 Years .................................................. 7 2.3. Recent Performance on Outcome Metrics, Annual and Normalized for Weather, Last 5 Years ............................................................................................................................... 7 2.4. Description of Additional Metrics ................................................................................... 8 2.5. Description of Program Targets ...................................................................................... 8 2.6. Detailed Information Supporting Outcome Metrics ....................................................... 9 2.7. Mapping Recent, Modelled, and Baseline Conditions .................................................... 9 3. Baseline Ignition Probability and Wildfire Risk Exposure ..................................................... 10 3.1. Recent Weather Patterns, Last 5 Years ......................................................................... 10 3.2. Recent Drivers of Ignition Probability, Last 5 Years ...................................................... 10 3.3. Recent Use of PSPS, Last 5 Years .................................................................................. 11 3.4. Baseline State of Equipment and Wildfire and PSPS Event Risk Reduction Plans ......... 11 3.4.1. Current baseline state of service territory and utility equipment ......................... 11 3.4.2. Planned additions, removal, and upgrade of utility equipment by end of three‐year Plan term ......................................................................................... 12 3.4.3. Status quo ignition probability drivers by service territory ................................... 12 4. Inputs to the Plan and Directional Vision for Wildfire Risk Exposure ................................... 13 4.1. Objectives of the Plan ................................................................................................... 13 4.2. Understanding Major Trends Impacting Ignition Probability and Wildfire Consequence .................................................................................................. 18 4.2.1. Service territory fire‐threat evaluation and ignition risk trends ............................ 29 4.3. Change in Ignition Probability Drivers ........................................................................... 32 4.4. Directional Vision for Necessity of PSPS ....................................................................... 33 5. Wildfire Mitigation Strategy and Programs for 2019 and For Each Year of the Three‐Year WMP Term ........................................................................................................ 37 5.1. Wildfire Mitigation Strategy ......................................................................................... 37 5.2. Wildfire Mitigation Plan Implementation ..................................................................... 43 5.3. Detailed Wildfire Mitigation Programs ......................................................................... 46 5.3.1. Risk assessment and mapping ............................................................................... 47 5.3.1.1. Summarized risk map: Operational Wildfire Risk Reduction Model ................ 49 5.3.1.2. Climate‐driven risk map and modelling ........................................................... 51 5.3.1.3. Ignition probability mapping ........................................................................... 52 5.3.1.4. Initiative mapping and estimation of wildfire and PSPS risk‐reduction impact ...................................................................................... 53 5.3.1.5. Match drop simulations .................................................................................. 54 5.3.1.6. Weather‐driven risk map and modelling ......................................................... 55 5.3.1.7. High‐performance computing infrastructure .................................................. 56 5.3.2. Situational awareness and forecasting .................................................................. 57 5.3.2.1. Camera network and advanced weather station integration .......................... 59 5.3.2.2. Continuous monitoring sensors ...................................................................... 60 5.3.2.3. Wireless fault indicators .................................................................................. 60 5.3.2.4. Forecast of a fire risk index, fire potential index, or similar ............................ 61 5.3.2.4.1. Fire science and climate adaptation department ............................................. 61 5.3.2.4.2. Fire potential index ............................................................................................... 62 5.3.2.4.3. Santa Ana wildfire threat index ........................................................................... 63 5.3.2.4.4. PSPS situational awareness dashboard .............................................................. 63 5.3.2.5. Operating conditions ....................................................................................... 64 5.3.2.6. Weather forecasting and estimating impacts on electric lines and equipment ................................................................................................ 65 5.3.2.7. Network management system situational awareness upgrades ..................... 65 5.3.3. Grid design and system hardening ........................................................................ 65 5.3.3.1. SCADA capacitors ............................................................................................ 69 5.3.3.2. Advanced protection ....................................................................................... 70 5.3.3.3. Distribution overhead system hardening ........................................................ 72 5.3.3.4. Covered conductor maintenance .................................................................... 74 5.3.3.5. Crossarm maintenance, repair, and replacement ........................................... 74 5.3.3.6. Pole replacement and reinforcement ............................................................. 74 5.3.3.7. Expulsion fuse replacement ............................................................................ 75 5.3.3.8. Grid topology improvements to mitigate or reduce PSPS events ................... 76 5.3.3.8.1. PSPS sectionalizing enhancements ..................................................................... 76 ii 5.3.3.8.2. Microgrids .............................................................................................................. 77 5.3.3.9. System automation equipment ....................................................................... 81 5.3.3.10. Hotline clamps ................................................................................................ 81 5.3.3.11. Mitigation of impact on customers and other residents affected during PSPS events .......................................................................................... 82 5.3.3.11.1. Customer resiliency programs ............................................................................. 82 5.3.3.11.2. Expanded generator grant program ................................................................... 83 5.3.3.11.3. Whole house generator program ....................................................................... 84 5.3.3.12. Other corrective action ................................................................................... 84 5.3.3.13. Pole loading infrastructure hardening and replacement program .................. 84 5.3.3.14. Transformers maintenance and replacement ................................................. 84 5.3.3.15. Transmission tower maintenance and replacement ....................................... 84 5.3.3.16. Strategic undergrounding ............................................................................... 85 5.3.3.17. Updates to grid topology to minimize the risk of ignition in HFTD .................. 87 5.3.3.17.1. Overheard transmission fire hardening ............................................................. 87 5.3.3.17.2. Cleveland National Forest fire hardening .......................................................... 89 5.3.3.18. Other ............................................................................................................... 90 5.3.3.18.1. Distribution communications reliability improvements .................................. 90 5.3.3.18.2. Lightning arrestor removal and replacement ................................................... 91 5.3.4. Asset