MADISON COUNTY, MONTANA TOWN OF ENNIS, MONTANA TOWN OF SHERIDAN, MONTANA TOWN OF VIRGINIA CITY, MONTANA PREDISASTER MITIGATION PLAN 2017 REVISION DRAFT TOPICAL REPORT RSI-2705 PREPARED FOR Beaverhead County, MT City of Dillon, MT Town of Lima, MT MAY 2017 respec.com MADISON COUNTY, MONTANA TOWN OF ENNIS, MONTANA TOWN OF SHERIDAN, MONTANA TOWN OF VIRGINIA CITY, MONTANA PREDISASTER MITIGATION PLAN 2017 REVISION DRAFT TOPICAL REPORT RSI-2705 PREPARED BY Zachary T. Collins, CFM, GISP RESPEC 3110 Valley Commons Drive, Suite 4 Bozeman, MT 59718 PREPARED FOR Beaverhead County, MT City of Dillon, MT Town of Lima, MT APRIL 2017 respec.com EXECUTIVE SUMMARY Disasters can strike at any time in any place. In many cases, actions can be taken before disasters strike to reduce or eliminate the negative impacts. These actions are called mitigation and often protect life, property, the economy, and other values. The Madison County Pre-Disaster Mitigation (PDM) Plan addresses 13 major hazards with respect to risk and vulnerabilities countywide, including the Towns of Ennis, Sheridan, Twin Bridges, and Virginia City. Through a collaborative planning process, the Madison County hazards were identified, researched, profiled, updated, and prioritized. The major hazards (i.e., aircraft accident, disease and environmental contamination, drought, earthquake, flood, hazardous material release, severe weather, terrorism and civil unrest, transportation accident, urban fire, utility and energy failure, volcanic ashfall, and wildfire) are each profiled in terms of their hazard description, history, probability and magnitude, mapping, vulnerabilities, data limitations, and other factors. The vulnerabilities to critical facilities; critical infrastructure; structures; the population; economic, ecologic, historic, and social values; and future development are updated for each hazard. Based on the probability and extent of potential impacts that were identified in the risk assessment, the prioritizations of hazards within Beaverhead County are displayed in Table ES-1. Note that individual jurisdictions have their own prioritizations based on the hazards and vulnerabilities specific to their locations but are generally similar to that of the county. Their priorities can be found in Section 4.14. Table ES-1. Madison County Hazard Prioritizations Level Hazard Earthquake Flood High Hazard Wildfire Utility and Energy Failure Winter Weather Communicable Disease Moderate Hazard Hazardous Matieral Release Structure collapse Drought Terrorism and Civil Unrest Transportation Accident Low Hazard Volcano Landslide and Avalanche The following goals are outlined in the plan’s mitigation strategy, based on the results of the risk assessment: / Goal 1: Encourage mitigation from multiple hazards through education and existing programs. / Goal 2: Reduce loss of life, injuries, and property damage in the event of an earthquake. / Goal 3: Reduce loss of life and prevent injury in the event of a hazardous material incident. i / Goal 4: Reduce or prevent loss of life and injuries and property damage in the event of flooding. / Goal 5: Reduce losses from wildfires in the wildland urban interface. RSI-2705 Working DRAFT / Goal 6: Minimize impacts from weather events such as severe thunderstorms and winter storms. Associated with each of the goals are objectives and mitigation actions that range from adopting building codes to burying electric infrastructure to community education. The mitigation projects are prioritized based on cost, staff time, feasibility, population benefit, property benefit, values benefit, project maintenance, and the probability and impact of the hazards being mitigated. An implementation plan outlines the suggested course of action, given the limited resources available to Madison County and the jurisdictions. The Madison County Local Emergency Planning Committee is responsible for implementing and maintaining the plan. Other recommended activities, such as integrating this plan into a variety of county, city, and town plans, regulations, and documents, will further the goals of hazard mitigation in Madison County. The Madison County plan exceeds the requirements of a local hazard mitigation plan as outlined in the Interim Final Rule published in the Federal Register on February 26, 2002, at Title 44 of the Code of Federal Regulations, Part 201 as part of the Disaster Mitigation Act of 2000 (DMA 2000). This plan has been approved by the Federal Emergency Management Agency (FEMA) as a hazard mitigation plan; therefore, the county and towns may be eligible for federal mitigation funds. This plan serves as a guide for understanding the major hazards that face Madison County and the jurisdictions and provides a strategy for preventing or reducing some of the impacts. ii RSI-2705 Working DRAFT TABLE OF CONTENTS 1.0 INTRODUCTION ............................................................................................................................................................... 1 1.1 PurposE ....................................................................................................................................................................................................1 1.2 Authorities ...............................................................................................................................................................................................2 1.3 Acknowledgements ...............................................................................................................................................................................2 1.4 Plan Scope and Organization .............................................................................................................................................................3 2.0 PLANNING PROCESS AND METHODOLOGIES ............................................................................................................... 6 2.1 Initial Planning Process ........................................................................................................................................................................6 2.2 Plan Update Process .............................................................................................................................................................................7 2.2.1 Community Changes .............................................................................................................................................................8 2.2.2 Plan Changes ...........................................................................................................................................................................8 2.2.3 Jurisdiction Participation .....................................................................................................................................................9 2.2.4 Public Participation ................................................................................................................................................................9 2.2.5 Incorporation of Existing Information ...............................................................................................................................10 2.3 Risk Assessment Methodologies .......................................................................................................................................................10 2.4 Hazard Identification ............................................................................................................................................................................13 3.0 ASSETS AND COMMUNITY INVENTORY ......................................................................................................................... 16 3.1 Critical Facilities and Infrastructure ..................................................................................................................................................16 3.1.1 Critical Facilities ......................................................................................................................................................................16 3.1.2 Critical Infrastructure ............................................................................................................................................................19 3.2 Population and Structures ..................................................................................................................................................................20 3.3 Economic, Ecologic, Historic, and Social Values ...........................................................................................................................23 3.4 Current Land Use ...................................................................................................................................................................................24 3.5 New Development..................................................................................................................................................................................24 3.6 Future Development .............................................................................................................................................................................27 3.6.1 Growth Policies ........................................................................................................................................................................27