People
People are your most important asset. The risk assessment should identify areas of greater population density as well as populations that may have unique vulnerabilities. Most hazard mitigation plans focus on physical vulnerability, that is, the risks hazards pose to structures such as houses, apartments, schools, hospitals and infrastructure. However, certain populations or groups may be especially vulnerable to disasters due to age, poverty, race, disability or language barriers. These socially vulnerable populations often face greater challenges preparing for, coping with and recovering from disasters. Hazard mitigation plans should address both physical and social vulnerability.
In addition, visiting populations might also be at greater risk. Visiting populations include students, second home owners, migrant farm workers, and visitors for special events. Special events could include large sporting events and festivals where large numbers of people are concentrated and vulnerable to hazards and threats. Visiting populations may be less familiar with the local environment and hazards and less prepared to protect themselves during an event.
The risk assessment should identify locations that provide health or social services that are critical to post-disaster response or recovery capabilities, including locations and support service operations for vulnerable populations (e.g., hospitals, dependent care facilities, oxygen delivery, and accessible transportation).
A variety of data sources are available to help collect information on population, such as the U.S. Census, state population estimates, and the U.S. Bureau of Labor Statistics. Creating maps that show facilities that house dependent populations or venues that host large numbers of people will help illustrate the relationship between population and potential hazards.
- Identify concentrations of residents and employees to help target preparedness, response, and mitigation actions.
- Identify the types of visiting populations and their likely locations to assess potential problems.
- Identify locations and concentrations of access and functional needs populations to develop mitigation actions that will best assist them.
- Consider demographics of projected population growth to predict vulnerability.
- Identify locations that provide health or social services that are critical to disaster recovery.
Best Practices
Fairfield, SC
Fairfield County’s plan was chosen as a best practice because it uses a social vulnerability index to identify populations particularly vulnerable to hazards. As the plan states:
“The Social Vulnerability Index (SoVI) is a statistical measure that compares social vulnerability to environmental hazards among places, and then visually displays these comparisons on a map. SoVI thus illustrates where there is uneven capacity for preparedness and response and where additional planning and response resources might be used most effectively to help residents.”
Gresham, OR
The City of Gresham’s hazard mitigation plan was identified as exemplary because it contains an extensive section on especially vulnerable populations. The plan discusses the ways in which low income people, ethnic minorities and elderly persons are more vulnerable to natural hazards especially because they tend to occupy lower quality housing. The figures below, included in the plan, identify the vulnerable populations within the city.
Hartford, VT
Hartford's plan assessed the number of persons who may be particularly vulnerable to hazards such as senior citizens living in affordable housing, persons living in mobile homes and persons living in shelters.
King County, WA
King County's plan included a table that identified the percentages of vulnerable population groups in the county.
Linn County, IO
Linn County’s Hazard Mitigation Plan was chosen as a best practice because it has implemented an emergency assistance registry. The registry is voluntary and includes people who are elderly, disabled or have a medical condition that may require special assistance evacuating their house during a vulnerability. The Plan includes the table below that shows the number of vulnerable persons in each area of Linn County.
Louisville, KY
Louisville was identified as a best practice because its hazard mitigation plan not only identified potentially vulnerable populations but it also mapped their population densities over the planning area.
Economy
After a disaster, economic resiliency drives recovery. Every community has specific economic drivers that are important to understand when planning to reduce the impacts of hazards and disasters to the local economy. Economic assets can be described in terms of direct or indirect losses; for example, building or inventory damage is direct, but functional downtime and loss of employment wages are indirect losses that can be calculated. In addition to the primary economic sectors in the community, such as manufacturing, agricultural, or service sectors, major employers and commercial centers also support the local economy.
- Identify major employers, primary economic sectors (e.g., agriculture), and commercial centers whose losses or inoperability would have severe impacts on the community and its ability to recover from a disaster.
- Assess dependencies between economic sectors and businesses and the infrastructure needed to support them.
Best Practice
Lewes, Delaware Lewes was chosen as a best practice because its plan maps the major economic centers within the 100-year floodplain (see the map below). The city also identifies its largest economic drivers, which include a medical center, the University of Delaware and the local school district.
Built Environment
Existing Structures
The built environment includes existing structures, infrastructure systems, critical facilities, and cultural resources. Areas of future growth and development are also an important component when assessing the building environment.
Existing Structures. All structures are exposed to risk, but certain buildings or concentrations of buildings may be more vulnerable because of their location, age, construction type, condition, or use. Consult the local tax assessor and planning department for information on land use, zoning, parcel boundaries and ownership, and types and numbers of structures.
Infrastructure. Infrastructure systems are critical for life safety and economic viability and include transportation, power, communication, and water and wastewater systems. Many critical facilities depend on infrastructure to function. For example, hospitals need electricity, water, and sewer to continue helping patients. As with critical facilities, the continued operations of infrastructure systems during and following a disaster are key factors in the severity of impacts and the speed of recovery.
Critical facilities. Critical facilities are structures and institutions necessary for a community’s response to and recovery from emergencies. Critical facilities must continue to operate during and following a disaster to reduce the severity of impacts and accelerate recovery. When identifying vulnerabilities, consider both the structural integrity and content value of critical facilities and the effects of interrupting their services to the community.
- Identify types of buildings, which include commercial, industrial, and single and multi-family residential.
- Determine the age and construction type of buildings to understand building codes in effect and quality of construction.
- Develop an inventory of the location, construction standards, age, and life expectancy of specific critical infrastructure and facilities in the planning area.
- Assess dependencies between infrastructure systems, critical facilities, and the people they serve.
- Review state and national historic registries and identify cultural assets, such as museums, that have significance to the community.
- Identify areas planned and zoned for future development and annexation.
- Identify location, numbers, and types of structures of planned new development and redevelopment.
- Review plans for new facilities, infrastructure, and other capital improvements, such as stormwater management infrastructure, to support existing and future development.
Best Practice
Morehead City, NC Morehead City was chosen as a best practice because its plan includes a map (click on map shown below for larger version) of all identified critical facilities and hazardous waste sites with an overlay of areas susceptible to identified hazards. Your community may choose to show the information over multiple maps (one map showing each hazard and critical facilities) to improve legibility.
Best Practice
Mecklenburg County, NC Mecklenburg County was chosen as a best practice because it is one of the few communities that considered planned future development in its vulnerability assessment. As the plan says: "[The City of Charlotte and Mecklenburg County] have long since gone above and beyond the minimum regulatory standards of the NFIP. This includes developing and adopting community floodplain maps that go beyond FEMA's standard for mapping only current flood risk but future floodplain conditions based on anticipated growth and development that will increase those risks." The county regulates development in this anticipated floodplain (which it refers to as the 'community floodplain'). The map below shows the FEMA floodplain and the community floodplain.
Natural Environment
Identify the most valuable areas that can provide protective functions that reduce the magnitude of hazard events.
Identify critical habitat areas and other environmental features that are important to protect.
Environmental assets and natural resources are important to community identity and quality of life and support the economy through agriculture, tourism and recreation, and a variety of other ecosystem services, such as clean air and water. The natural environment also provides protective functions that reduce hazard impacts and increase resiliency. For instance, wetlands and riparian areas help absorb flood waters, soils and landscaping contribute to stormwater management, and vegetation provides erosion control and reduces runoff. Conservation of environmental assets may present opportunities to meet mitigation and other community objectives, such as protecting sensitive habitat, developing parks and trails, or contributing to the economy.