Flood Risk
Environmental Risk Factor
Flood risk measures the likelihood and potential severity of flooding in a given area. Flooding is the most common and costly natural disaster in the United States, causing billions in damage annually. Risks come from river flooding, coastal storm surge, flash floods from heavy rainfall, and urban flooding from overwhelmed drainage systems. Climate change is increasing flood risk in many areas through more intense rainfall events, sea-level rise, and changing storm patterns. Many homeowners are unaware they live in flood-prone areas, and standard homeowner insurance does not cover flood damage.
How It's Measured
Flood risk is assessed using FEMA Flood Insurance Rate Maps (FIRMs) that designate Special Flood Hazard Areas. Zone designations include Zone A and AE (high-risk riverine), Zone V and VE (high-risk coastal with wave action), Zone X (moderate-to-low risk), and Zone D (undetermined). We also consider historical flood data, topography, proximity to water bodies, drainage infrastructure capacity, and climate projections for future flood risk.
Health Effects
- ⚠️Drowning is the leading cause of flood-related death
- ⚠️Waterborne disease outbreaks from contaminated floodwater
- ⚠️Mold growth in flooded homes causing respiratory illness
- ⚠️Mental health impacts including PTSD, anxiety, and depression
- ⚠️Exposure to hazardous materials displaced by floodwater
- ⚠️Injuries from debris and structural damage
Data Sources
- 📊FEMA National Flood Insurance Program flood maps
- 📊NOAA National Weather Service flood records
- 📊USGS stream flow monitoring data
- 📊First Street Foundation flood risk assessments
How to Protect Yourself
- ✓Check your FEMA flood zone at msc.fema.gov
- ✓Purchase flood insurance even if not in a high-risk zone
- ✓Elevate critical utilities above potential flood levels
- ✓Install check valves to prevent sewer backup during floods
- ✓Create an emergency plan with evacuation routes
- ✓Keep important documents in waterproof containers above ground level