Severe storms and floods can cause environmental and public health problems. Severe storms include thunderstorms, heavy rains, strong winds, hurricanes and cyclones, and storm surge. Catastrophic flooding can be caused by any of these severe storms or by tsunamis. Thunderstorms are local storms accompanied by rain, lightning, and thunder. A cyclone is a large-scale circulation of strong winds around a central core or "eye". A hurricane is a cyclone in the Western Hemisphere that starts in the tropics and has winds above 74 miles per hour. A tsunami is an ocean wave produced by an earthquake, landslide, or volcanic eruption. Tsunamis can travel across entire oceans and cause severe flooding when they make landfall. Storm surge is very high tides and waves, driven by strong hurricane winds, that flood coastal areas.

Severe storms and floods can create solid waste, debris, and polluted flood water which can contaminate drinking water, soil, and food with toxic chemicals. They can cause power failures, threaten above-ground and underground storage tanks, and make roads and bridges unsafe. Damaged or flooded septic systems or wastewater treatment facilities can result in raw sewage contaminating flood water. A flooded septic system can contaminate nearby drinking water sources. 

Severe storms and floods can cause drowning and injuries if people are caught in flood waters or hit by falling or flying objects. A tsunami can cause drowning and severe injuries if people are caught in the incoming wave or in the powerful suction of the water rushing back out to sea that follows. 

Evacuations may be necessary before a severe storm. A storm can damage homes and buildings, forcing people to seek shelter during and after the storm. If you leave your home, don’t return until you are told it is safe to do so. After a flood, electrical power, natural gas, and propane tanks can pose a risk of fire, electrocution, or explosions. Emergency generators can emit dangerously high levels of carbon monoxide and must be used or vented outside. After a flood, mold may grow on household materials and belongings that are wet. Mold can cause difficulty breathing, irritated eyes and skin, and other health problems. 

If polluted floodwaters linger after a storm, there’s the possibility of infection from wading in the flood waters or using the water for drinking and cooking. Flooding may also leave pools of water used for breeding by disease-transmitting mosquitoes. 

Tox Town information on how the post-disaster environment and clean-up efforts can affect people’s health is listed in the A-Z Disasters index.

Web Links from MedlinePlus (National Library of Medicine)
Coping with Disasters
Disaster Preparation and Recovery
Floods
Hazardous Waste
Hurricanes
Tornadoes
Tsunamis
Winter Weather Emergencies

More Links
Flooding and Communicable Diseases (World Health Organization)
Floods (Centers for Disease Control and Prevention)
Hurricane eMatrix: Response and Recovery Work (Occupational Safety and Health Administration)
Hurricanes (Centers for Disease Control and Prevention)
Keeping Workers Safe During Clean Up and Recovery Operations Following Hurricanes (Occupational Safety and Health Administration)
Tsunamis (Centers for Disease Control and Prevention)

Chemicals in Storms and Floods
Are these chemicals in MY environment?
Acetone
Ammonia
Benzene
Chromium
Diesel
Formaldehyde
Gasoline
Lead
Mercury
Perchloroethylene
Pesticides
Phthalates
Polychlorinated Biphenyls
Solvents
Toluene
Volatile Organic Compounds

Last Updated: July 08, 2008