Contaminated Flood Water

How Does Contaminated Flood Water Affects Our Health?

Jane Marsh - August 26, 2019

We are reader-supported. When you buy through links on our site, we may earn affiliate commission.

A flood is a natural occurrence where water covers once-dry land. It can have a positive impact on an ecosystem, especially one experiencing prolonged drought. Unfortunately for most, it can also have a deadly effect.

Flooding typically happens after heavy rainfall when waterways – like rivers, creeks and ponds – can’t hold the new water. In coastal cities, tropical cyclones, tsunamis and high tide combined with high river levels cause floods.

Natural disasters are worsening with global warming. As temperatures rise, so does the risk of tropical cyclones and intense storms. Experts say a warmer climate could produce fewer storms – but they will be much more destructive.

If you get caught in a flood situation, you can reduce health risks by avoiding the water.

The Physical Toll

You never know what’s in floodwater. Downed power lines, which can be hidden from sight, pose an electrical hazard. Debris like lumber, broken glass and metal fragments can cause cuts and injury, which may lead to an infection.

Another concern is bites from wild and domestic animals that got lost. Be on the lookout for insects, rodents and reptiles, like snakes and rats. Mosquitos are a major concern, as they can carry diseases like Zika and West Nile Virus. After Hurricane Katrina, West Nile Virus cases doubled in the area.

Drowning in floodwater is a severe risk to everyone. When water moves rapidly – typically near natural waterways – adults can get swept away. Children are at risk in standing floodwater. Even a vehicle does not offer protection against the inundation of water.

The Risk of Contamination

Only 2.5% of the Earth’s water is freshwater. When a flood comes along, it contaminates fresh sources with industrial, agricultural and household pollutants. Floodwater mixes with everything it touches, including chemicals, solvents, pesticides and animal waste.

One major concern is sewage, which can contain E. coli and Salmonella. Anything people drink or eat that’s tainted can cause diarrheal disease.

Floodwater also carries household pollutants, including:

  • Drain cleaner
  • Furniture stripper
  • Toilet bowl cleaner
  • Motor oil
  • Antifreeze

According to Dr. Richard Bradley, the chief of disaster medicine at the University of Texas Health Science Center at Houston, “The bacterial count in floodwater is extremely high. The chance of getting a skin infection is really quite serious.” Other side effects from exposure include flu symptoms like upset stomach, headache and intestinal problems.

You should also be aware of mold, which flourishes after flooding due to excessive moisture. Following Hurricanes Katrina and Rita, the CDC (Center for Disease Control) discovered 46% of inspected homes had mold.

Without protection, those living near mold can develop respiratory problems. If you have to clean up after a flood, you need to wear proper safety equipment like shoes, gloves and a surgical mask. You should also remove absorbent items that can encourage mold, like carpeting, clothing and wallpaper.

The Water Problem

During a natural disaster, many people end up wading through floodwater to evacuate, look for others and save belongings. If you need to step foot in the water, take extreme caution.

Check your body for open wounds. Even a small cut, scrape or rash can lead to infection. Once in the water, the wound becomes exposed to all the bacteria and pollutants. Before you go in, cover the area with a waterproof bandage. Keep the wound as clean by washing it with soap and water. If you notice signs of infection – like redness, swelling or pus – seek medical attention immediately.

Another concern is trench foot, which occurs when your feet are wet, even damp, for long periods. It can be quite painful and starts with symptoms like tingling sensations, pain, swelling and numbness. To avoid a foot infection, clean and dry your feet each time you get out of the water, then put on fresh socks.

The Way to Stay Safe

When stuck in a natural disaster, the goal is to minimize health risks, including pollution. If you have time, move hazardous household materials to a secure area before the water arrives.

Move vehicle batteries and propane tanks to higher ground. Batteries, like power lines, pose an electrical risk when in contact with water. Propane tanks, on the other hand, have the potential to catch fire.

If your water supply comes from a well, be aware of potential contamination. Wells that are tainted will need to be cleaned and tested prior to reuse.

Due to freshwater scarcity during natural disasters, many organizations are looking into reclaimed or recycled water as a solution. Reclaimed water – which can be wastewater, runoff or stormwater – is used more than once before it’s released back into the environment.

One setback, however, is public perception. While treated and safe to drink, many still view reclaimed water as unsanitary. In the meantime, bottled water is the go-to during a natural disaster, which perpetuates the plastic waste problem.

You can’t stop a natural disaster. Experts predict the severity of these events, including floods, will only worsen with time. If you get stuck in a flood, your goal is to protect your health and safety. When possible, stay far away from the water, and if you must get in, take precautions to cover open wounds and thoroughly clean up afterward.

Share on

Like what you read? Join other readers!

Get the latest updates on our planet by subscribing to the newsletter!

About the author

Jane Marsh

Starting from an early age, Jane Marsh loved all animals and became a budding environmentalist. Now, Jane works as the Editor-in-Chief of where she covers topics related to climate policy, renewable energy, the food industry, and more.