Understanding Your Area's Risk Score (NRI)

At MAD Gear, we believe that being informed is the first step to being prepared. As part of our commitment to helping you understand potential risks, our Local Threat Assessment Tool provides data that includes a risk score for your area. This score is derived from the FEMA National Risk Index (NRI).

What is the FEMA National Risk Index (NRI)?

The NRI is a publicly available dataset and online tool developed by the Federal Emergency Management Agency (FEMA). It provides a comprehensive overview of natural hazard risk across the United States. The goal of the NRI is to help communities understand and mitigate their risks from various natural hazards.

Where Does the Data Come From?

The NRI combines data from multiple reputable sources, including:

• National Oceanic and Atmospheric Administration (NOAA)
• U.S. Geological Survey (USGS)
• U.S. Census Bureau
• Other academic and governmental organizations

This data covers various natural hazards such as earthquakes, floods, hurricanes, wildfires, tornadoes, winter weather, and more.

How is the NRI Score Calculated?

The NRI calculates a risk score for each U.S. county and census tract. This score is not just about how often a hazard occurs, but also considers:

1. Expected Annual Loss (EAL): This is a measure of the estimated average economic loss from natural hazards each year. It considers potential damage to buildings, agriculture, and impacts on human life (quantified economically). A high EAL means that, on average, a hazard is expected to cause significant financial damage annually in that area.
2. Social Vulnerability: This assesses the susceptibility of social groups to the adverse impacts of natural hazards. Factors include poverty, elderly populations, disability, and access to transportation. Higher social vulnerability can increase a community's overall risk.
3. Community Resilience: This measures a community's ability to prepare for, withstand, and recover from a natural hazard event. Factors include building codes, emergency preparedness measures, infrastructure robustness, and access to resources. Higher community resilience can decrease a community's overall risk.

The general formula can be thought of as:

 $Risk\approx \; (ExpectedAnnualLoss\times SocialVulnerability)÷CommunityResilience$

A higher NRI score (typically on a scale of 0-100, representing percentiles) indicates a relatively higher risk from natural hazards when considering these combined factors. It doesn't mean a disaster is imminent, but rather that the potential for impact, considering economic losses and community characteristics, is greater compared to areas with lower scores.

Why a Score Might Not Make Sense at First Glance: An Example with Winter Weather

Sometimes, an NRI score for a specific hazard might seem counterintuitive. For instance, a county in Texas might show a surprisingly high Winter Weather Risk Index score, perhaps even higher than a county in Massachusetts, which experiences frequent and heavy snowfall.

Here's why that can happen:

• Massachusetts (e.g., Suffolk County - Boston area):

  • Experience & Frequency: Experiences frequent winter storms.
  • Expected Annual Loss (EAL) for Winter Weather: While events are common, the infrastructure (buildings, roads, power grid) is generally built to withstand typical winter conditions. Snow removal is efficient, and the population is accustomed to such weather. This means the economic loss per event or averaged annually might be significant due to frequency but is managed.
  • Community Resilience for Winter Weather: Likely has a high Community Resilience score for this hazard due to strong building codes for snow loads, established emergency plans for snow, and experienced public services.
  • Resulting Winter Weather Risk Score: May be "Relatively Moderate" or "Relatively High" due to frequency, but tempered by high resilience.

• Texas (e.g., a county heavily impacted by a past ice storm like Harris County - Houston area):

  • Experience & Frequency: Experiences severe winter weather much less frequently.
  • Expected Annual Loss (EAL) for Winter Weather: When a significant winter storm does occur (like an ice storm or prolonged deep freeze), the impact can be catastrophic and widespread. Infrastructure (e.g., power grid, plumbing) is often not designed for such conditions, leading to massive economic losses from burst pipes, prolonged power outages, and business disruptions. So, while less frequent, the loss when it happens is enormous, driving up the annualized average loss.
  • Community Resilience for Winter Weather: Likely has a lower Community Resilience score for this specific hazard. Because it's an infrequent event, there may be less investment in specific mitigation measures (like widespread grid winterization or stringent cold-weather building codes) compared to areas where it's a yearly certainty.
  • Social Vulnerability: If the Texas county also has higher social vulnerability, the impact of infrastructure failure during such an event is exacerbated.
  • Resulting Winter Weather Risk Score: Could be "Relatively High" or even "Very High," surprising those who only consider frequency. The high potential for severe economic damage and disruption during infrequent but impactful events, coupled with lower specific resilience for that hazard, drives the score up.

This example shows that the NRI isn't just counting how often a storm hits. It's assessing the potential for harm and loss when it does, considering how well the community can handle it and who is most likely to suffer.

What Does a High NRI Score Mean for Me?

Seeing a high NRI score for your area can be concerning, but it's important to understand what it signifies:

• It's a Planning Tool, Not a Prediction: The NRI score is a planning tool to help understand relative risk. It does not predict when or where a specific disaster will occur.
• Highlights Potential Vulnerabilities: A high score can indicate that your community may experience higher-than-average impacts if a natural hazard event occurs. This could be due to frequent hazard exposure, significant potential economic losses, or social factors that might make recovery more challenging.
• Empowers You to Prepare: This information is powerful. Knowing your area's potential risks allows you to take proactive steps. This is where MAD Gear comes in – our planners and resources are designed to help you prepare for a wide range of contingencies, regardless of your area's specific score. A higher score might encourage you to:
  • Develop more robust emergency plans tailored to the identified risks.
  • Invest in specific preparedness supplies relevant to those risks.
  • Strengthen your home or business against potential hazards.
  • Get more involved in community preparedness efforts.

Our Commitment:

We provide this information to help you make informed decisions. The NRI data is a valuable resource, and understanding its components can help you better prepare yourself, your family, and your community. While the data is compiled and calculated by FEMA using established methodologies, it's one of many tools you can use for risk assessment.

We encourage you to visit the official FEMA NRI website for more detailed information and to explore the data for your specific location.

Remember, preparedness is about taking control in uncertain situations. Understanding your environment is a key part of that process.