Coastal Services Center

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Risk and Vulnerability Assessment Steps Societal Analysis and Extended Discussion

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Why would I do this analysis?

Societal vulnerability analyses can help you identify potential areas of special needs populations. Such areas often contain higher concentrations of low-to-moderate income households that would most likely require public assistance and services to recover from disaster impacts. Yet another potential societal concern would be areas with a high concentration of non-English-speaking residents.

Preparedness materials and/or official advisories issued by emergency officials (e.g., hurricane evacuations) may need to be customized so that all residents can understand them. A societal vulnerability analysis could help you identify areas in which to concentrate your outreach efforts. The primary purpose for defining these special consideration areas in a vulnerability assessment is to identify locations for targeting effective hazard mitigation strategies.

Give me an example of something I might do in this analysis.

Using data collected from the U.S. Census Bureau (or data from some other study of population demographics — again, local data are preferable), you analyze your population to determine potential vulnerabilities. For example, through your analyses, you identify areas containing high concentrations of minority populations. These may represent areas where cultural considerations or foreign language interpreters may be necessary for public service announcements regarding evacuation, sheltering, and recovery operations. City and/or county officials may choose to develop a targeted campaign to distribute culturally relevant awareness materials to help these individuals better navigate the pre- and post-disaster environment.

What are my steps?

1. Locate, gather and process data
2. Assign scores to special consideration areas (higher rankings should indicate higher risk or higher potential vulnerability)
3. Identify vulnerable locations (areas with highest scores)
4. Focus your assessment and mitigation activities on areas containing the highest vulnerability

What data will I need?

Detailed (block or block group) community demographics (most of this information, listed below, can be found in one dataset)

• Poverty
• Elderly
• Minorities
• Single-Parent Households
• Rental Dwellings
• No High School Diplomas
• Public Assistance Recipients
• Non-English Speaking Populations
• No Vehicle Available
• Transient Populations

Where can I obtain these data and information?

Every ten years, the U.S. Census Bureau collects and publishes detailed demographic data down to the block level. New data are typically released two years following each study analysis period. In addition to Census data, local officials may be able to provide even more detailed demographic data and information that can help identify special consideration areas located within their area of responsibility. Even if digital (GIS) data are not available beyond Census data, it is still possible to complete an analysis using transparencies overlaid on paper maps.

Who do I need to work with? What agencies can help me locate the necessary data and information?

To access many of these governmental and organizational Web sites, view the Links page.

Local (county or municipality level) — City/County Administration, Planning, Emergency Management, and others.

Regional (state level) — Emergency Management, non-governmental organizations, and others.

National (federal level) — U.S. Census, U.S. Immigration and Naturalization Service, FEMA, Social Security Administration, Environmental Systems Research Institute (ESRI) Tiger^® Census data, and others.

Potential Partners/Stakeholders List

Local (county or municipality)

• Entity with authority to direct and implement the Hazard Mitigation Plan
• Mayor
• County, City, and Town Manager
• Chamber of Commerce
• Regional/County/Local Emergency Managers
• National Flood Insurance Program Coordinator
• Community Rating System Coordinator
• Coastal Zone Management
• Regional/Local Planning Commissions
• County/City Planning Department
• County/City Public Works Department/Utilities
• Electrical Membership Coops.
• County/City Engineering Department
• Finance Department
• Construction Development (contracts, permits)
• Building and Zoning
• Tax Assessor
• Public Safety/Fire/ Law Enforcement
• Code Enforcement
• Parks and Recreation
• GIS staff
• Health Department
• American Red Cross
• Economic Development Administration (local chapter)
• League of Municipalities/Cities
• Local Business Leaders
• Developers
• General public (citizens)
• Special Interest Groups
• Media
• Land Trusts/Nature Conservancies
• Board or Realtors
• Small Business Administration
• Tourism Development Council
• Academia

Regional (state or states)

• Coastal Zone Management Program
• State Emergency Management Agencies - State Hazard Mitigation Officer
• State Floodplain Manager
• State Hurricane Program Manager
• State Earthquake Program Manager
• Department of Insurance
• State Natural Resource Agencies (departments and divisions vary by State)
• State Department of Transportation
• State Ports Authority
• State Historic Preservation Office
• National Guard
• Law Enforcement
• Division of Solid Waste
• Division of Hazardous Waste
• Division of Public Works (Waste Water and Water Treatment)
• Division of Water Quality
• GIS Clearinghouse staff
• State Climatologist
• Academia

National (federal)

• NOAA National Weather Service (NWS)
• U.S. Department of Homeland Security
• Federal Emergency Management Agency (FEMA) - Recovery (Infrastructure and Environmental), Flood Insurance and Mitigation Administration
• US Fish and Wildlife Service (USFWS)
• US Army Corps of Engineers (USACE)
• US Geological Survey (USGS)
• Federal Highway Administration/ Federal Department of Transportation (FWA/FDOT)
• US Coast Guard (USCG)
• Environmental Protection Agency (EPA)
• Small Business Administration (SBA)
• National Historic Preservation Office (NHPO)
• US Military

Extended Discussion

Objective(s):

Map special consideration areas; identify vulnerable populations and or areas

Purpose:

Target priority areas for the remaining assessment

Primary Steps:

1. Locate, gather, and process data
2. Assign scores to special consideration areas
3. Target areas for vulnerability assessments and outreach activities

Description

A societal vulnerability assessment examines the vulnerability of people of different ages, income levels, ethnicity, capabilities, and experiences to a hazard or group of hazards.

Special consideration areas are those where personal resources or characteristics are such that their ability to deal with hazards is limited. For example, these areas generally contain higher concentrations of low-to-moderate income households that would be most likely to require public assistance and services to recover from disaster impacts. Structures in these areas are more likely to be uninsured or underinsured for hazard damages, and persons may have limited financial resources for pursuing individual hazard mitigation options.

These are also areas where other considerations such as mobility, literacy, or language can significantly impact disaster recovery efforts. These areas could be most dependent on public resources after a disaster and thus could be good investment areas for hazard mitigation activities. In fact, the primary purpose for defining these special consideration areas in a vulnerability assessment is to identify locations for targeting effective hazard mitigation strategies. By focusing on these areas, communities can help reduce the vulnerability of individuals and also help reduce the requirements for public services as well.

Examples of Vulnerable Populations

In the absence of more detailed, accurate data collected at the local level, publicly available census data at the block or block group level can be used for this analysis. Demographic characteristics can be selected to help identify special consideration areas. In this analysis, eight categories were selected from U.S. Census data and classified as high-need determinant factors:

Percent Non-white Population

Indicates potential language, cultural, or health considerations. Non-white populations may also represent areas where foreign language interpreters may be necessary.

Percent Households below Poverty

Indicates limited resources. Poverty and public assistance income may indicate areas where even moderate damages could have significant financial impacts on residents.

Percent Persons over Age 65

Elderly populations and lack of vehicles may indicate special mobility needs.

Percent Single Parent with Child Families

Indicates areas where special child care considerations could be necessary.

Percent No High School Diploma

Indicates possible need for personal interactivity instead of written communication. Low educational attainment rates may indicate the need for specialized help in dealing with disaster assistance procedures.

Percent Households with Public Assistance Income

Indicates households likely to require public disaster aid (i.e., temporary or long-term housing, money, services, etc.).

Percent Rental Housing

Indicates households where contents are least likely to be insured, making the pursuit of structural hazard mitigation even more difficult.

Percent No Vehicle Available

Indicates possible reliance on public transportation for mobility.

For each category listed, census block groups were ranked and divided into five divisions. Those block groups with percentages in the highest division were given a score of 5, the second highest were given a score of 4, the third highest a score of 3, the next lowest a score of 2, and the lowest a score of 1. After this process was completed for all categories, the scores for each block group were totaled to determine a societal risk summary score.

Combine Risk Areas with Special Consideration Areas

To further target areas for potential hazard mitigation activities, you should identify areas that are located in high-risk zones. The identification of risk areas within the special consideration block groups helps to assess the overall risks to the population and aids in targeting and prioritizing hazard mitigation options. To help prioritize potential mitigation options, conduct a general inventory of structures in the special consideration/high-risk intersections. By providing a count of residential units within these areas, the special consideration households to be targeted for assistance can be summarized, indicating their level of vulnerability to each hazard.

There are a number of ways to complete this type of inventory. In some cases, communities will choose to conduct a parcel-by-parcel driving survey to determine the number and type of vulnerable facilities in high-risk areas. A parcel-based land use inventory, available in a GIS format, can provide the quickest and easiest method of analysis. This inventory can be used to identify the number and type of residential structures located in the special consideration block groups. Residential units can then be given scores corresponding to their hazard risk summary scores.

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