Río Grande Municipio, Puerto Rico Natural Disaster Risk
FEMA National Risk Index assessment · PR
Very LowComposite Risk Score
National percentile: 0th
Río Grande Municipio faces very low composite natural disaster risk (NRI Risk Index score 0.0, 0th national percentile), driven primarily by a mix of natural hazards exposure. Expected annual loss across all 18 hazard types is $41M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Río Grande Municipio is very low, with a National Risk Index score of 0.0 out of 100 — placing it in the 0th national percentile and among the lowest-risk counties in the country. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
No individual hazard records measurable expected loss in Río Grande Municipio in the current dataset, which keeps its overall expected annual loss low at $41M.
Beyond physical exposure, Río Grande Municipio has a very low social vulnerability rating (how susceptible the population is to harm) and a very low community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
History supports the rating: Río Grande Municipio has received 26 federal disaster declarations since 1970, including 13 for hurricane events and 5 for flood events. The most recent was Tropical Storm Ernesto (tropical storm), declared in November 2024.
Among 78 Puerto Rico counties, Río Grande Municipio ranks #61 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.21 / yr | $38K |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Drought | Very Low | 1.49 / yr | $0 |
| Earthquake | Very Low | 0.04 / yr | $8M |
| Hail | Very Low | 0.03 / yr | $744 |
| Heat Wave | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.22 / yr | $24M |
| Ice Storm | Very Low | 0.00 / yr | $0 |
| Riverine Flood | Very Low | 0.89 / yr | $3M |
| Landslide | Very Low | 4.64 / yr | $2M |
| Lightning | Very Low | 68.11 / yr | $593K |
| Strong Wind | Very Low | 0.00 / yr | $204 |
| Tornado | Very Low | 0.00 / yr | $13K |
| Tsunami | Very Low | 0.06 / yr | $3M |
| Volcanic Activity | Very Low | 0.01 / yr | $0 |
| Wildfire | Very Low | 0.00 / yr | $0 |
| Winter Weather | Very Low | 0.00 / yr | $0 |
Disaster History
Río Grande Municipio has received 26 federal disaster declarations since 1970, most recently Tropical Storm Ernesto in November 2024. Most frequent causes: Hurricane (13), Flood (5), Severe Storm (4).
| Declared | Type | Disaster |
|---|---|---|
| November 2024 | Tropical Storm | Tropical Storm Ernesto |
| August 2024 | Severe Storm | Tropical Storm Ernesto |
| September 2022 | Hurricane | Hurricane Fiona |
| September 2022 | Hurricane | Tropical Storm Fiona |
| August 2020 | Hurricane | Tropical Storm Laura |
| July 2020 | Hurricane | Potential Tropical Cyclone Nine |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| January 2020 | Earthquake | Earthquakes |
| August 2019 | Severe Storm | Tropical Storm Dorian |
Showing the 10 most recent of 26 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Río Grande Municipio?
Río Grande Municipio has a composite FEMA National Risk Index score of 0.0 out of 100, placing it in the Very Low category and the 0th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Río Grande Municipio?
The three highest-rated hazards are Avalanche (Very Low, $0 EAL), Coastal Flood (Very Low, $38K EAL), Cold Wave (Very Low, $0 EAL). These account for most of the county's expected annual losses.
How does Río Grande Municipio compare to other Puerto Rico counties?
Río Grande Municipio ranks #61 of 78 Puerto Rico counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Río Grande Municipio had?
FEMA records 26 federal disaster declarations for Río Grande Municipio since 1970, most often 13 for hurricane events and 5 for flood events. The most recent was Tropical Storm Ernesto, declared in November 2024.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Río Grande Municipio's $41M EAL is a statistical average, not a guarantee for any specific year or address.