FEMA National Risk Index
The Federal Emergency Management Agency (FEMA)’s National Risk Index (NRI) is a mapping tool that can help communities across the U.S. understand their relative risk and resilience related to natural hazards. The NRI identifies the relative vulnerability of all counties and census tracts within the U.S.to 18 natural hazards.. The relative vulnerability is based on detailed data and estimates of expected annual economic losses, social vulnerability, and community resilience.
States and communities can use this tool to understand local-level relative risk levels to a variety of natural hazards, which can assist with hazard mitigation planning.
The NRI is intended to be used to help set priorities for resilience efforts by enabling users to quickly assess information on relative risks, social vulnerability, and resilience capacity by county and census tract. FEMA states that the NRI can be used to educate risk managers and the public, and can help inform any updates or development of hazard mitigation plans. Policymakers can also use the NRI to identify where more refined risk assessments or improvements in building standards or codes may be needed.
The NRI calculates relative risk as a function of three inputs:
- Expected Annual Loss (EAL)
- Social Vulnerability
- Community Resilience
The Expected Annual Loss combines estimates of annual economic damages to people, buildings, and agriculture from 18 natural hazards. The hazards are those that are either widespread nationally (e.g., flooding) or important in some regions (e.g., coastal flooding, avalanches). The natural hazards include: Avalanche, Coastal flood, Drought, Earthquake, Extreme temperatures, Flood, Hail, Hurricane, Landslide, Lightning, Sea level rise (with coastal flooding), Severe summer weather, Tornado, Tsunami/Seiche, Volcano, Wildfire, Wind, and Winter weather.
The estimate of Social Vulnerability is developed using the Social Vulnerability Index (SoVI) developed by the University of South Carolina’s Hazards and Vulnerability Research Institute. The index combines several dozen factors including wealth, race, ethnicity, access to health insurance, employment, and gender.
The estimate of Community Resilience used is based on the Baseline Resilience Index for Community risk (BRIC), also developed by the University of South Carolina's Hazard and Vulnerability Research Institute. This index also involves many factors, including educational attainment, share of population speaking English, access to medical care, homeownership, income inequality by race and gender, quality of housing stock, access to the internet, communities’ preparation and experience with disasters, social networks and connectivity (e.g., volunteerism, religious and political engagement), and natural resource base and environmental conditions such as access to food and clean water.
Higher Expected Annual Losses and Social Vulnerability increases relative risks, while higher Community Resilience decreases relative risks in the NRI. Users will find that the national map of relative risk can differ based on whether risk is assessed as the county or census tract levels.
FEMA notes that the tool is meant to support planning processes, and should not be used by itself for a local risk analysis. FEMA advises using local data, if available, to estimate local risks.
FEMA’s NRI was published in 2019 and was the result of three years of work by scores of researchers from federal, state, and local government agencies, research institutions at universities, and consulting firms. A primer on the NRI and technical documentation can be downloaded from the FEMA NRI website.
Publication Date: 2019
- Mapping tool
- Tool (general)