Seven health impacts of flooding and how to mitigate risks

Natural disasters occur when the natural processes of the earth are disturbed or out of control, for example, firestorms, floods, tornados, etc. Several reasons found by scientists explain how such disasters happen. 

According to NCBI, natural disasters like floods cause extreme morbidity and mortality. The impact of these floods on humans is associated with the location and topography of the area. However, human demographics and the characteristics of the environment also cause floods. 

According to the NOAA National Severe Storm Laboratory, flooding is an overflow of water on dry land. It may occur due to heavy rains, snow melting, ocean waves coming to the shore, or when dams break. Floods are the most common weather-related natural disaster; they can occur within minutes or may take weeks or days. Flooding causes immense disasters and health impacts, the destruction of buildings, crops, food, the emergence of diseases, and mortality. 

However, several risk mitigations strategies help avoid the risks and health impacts caused by natural disasters. If you are interested to know the health impacts and risk mitigation strategies for floods, you can view them below:

  • Preparation:

The first and foremost thing is to survive a flood disaster. You must assess risks, plan your strategy and endure any challenges you face during that time. Start by preparing for natural disasters, pack up the necessities and tools, consider evacuation plans and gather the information you will need to survive the journey. 

National authorities evacuate countries or cities to save lives during a flood disaster. Therefore, you must prepare beforehand to endure the unpleasant traveling, camping, and food shortage conditions. 

  • Unsafe food:

The most common problem/risk that arises during flooding is the contamination of food by bacteria, oil, dirt, human or animal waste, or hazardous chemicals. During flooding, food and crops get mixed up with waste and chemicals that make it highly unsafe to eat. According to NCBI, power outages during flooding can cause Salmonella in stored and frozen food, thus, making it extremely dangerous to health. 

A CDC fact sheet also highlights that food stored in plastic jars and cardboard boxes contaminated with flooded water is unsanitary and has mold growth. 

Therefore, to mitigate this risk and avoid food-borne illnesses and other health issues, you must eat only canned foods. 

  • Contaminated drinking water:

Another health impact of flooding is the non-availability of clean water. According to WHO, contaminated water systems during flooding cause severe water-borne illnesses, for example, diarrhea. Another endemic prone infection, leptospirosis: an animal to human transmitted disease, can occur if skin comes into contact with water, soil, vegetation, or mud mixed with rodent urine. 

Flooding and heavy rainfall increase the production of rodents which spread this disease. The crucial risk factor for outbreaks is the scarcity of clean drinking water during a flood disaster. However, well-recognized risk identification systems and disaster responses that address the provision of clean water can minimize this risk.

  • Vector diseases: 

According to the Montana Department of Public Health and Safety, excessive rainfall and stagnant water pools can provide a breeding ground for mosquito-borne diseases, for example, malaria, dengue, and West Nile fever. Mosquitoes are born in stagnant water and carry several diseases that affect human health. 

A flood disaster can produce hundreds and millions of these insects. According to WHO, Malaria outbreaks in Costa Rica, ENSO, and West Nile outbreaks in Europe are linked directly to periodic flooding or constant heavy rainfall. 

Human activities, for example, overcrowding, sleeping outside without mosquito nets, delayed disease control measures, habitat changes, deforestation, land sliding, and river damming, have increased the risk for these outbreaks. 

However, proper risk management strategies, mosquito repellents, and insecticide sprays can help reduce this risk.

  • Animal and plant diseases:

Flooding can cause an increase in animal and plant diseases. 

During a flooding disaster, ingestion of contaminated drinking water causes several bacterial, viral illnesses, or in severe cases, it can cause the death of animals. 

Several toxins discharged from dead animals’ bones cause complete paralysis, for example, Clostridial. 

Plants taking up contaminated water can wilt, die or produce polluted crops that are not suitable for consumption. A flood disaster also causes an increase in root rot pathogens that destroy the plants and crops. 

According to CDC, proper disposal of dead or infected animals by official guidelines and local animal authorities can help minimize the risk of cross-contamination, zoonotic diseases, food-borne illnesses, and toxins.  

  1. Mold and mildew growth:

Another health impact of flooding is the overgrowth of mold and mildews. According to FEMA 2015, prolonged mold exposure can cause upper respiratory tract illnesses, cold, sneezing, wheezing, shortness of breath, and watery eyes. It can also trigger asthma and allergy in many flood victims. 

Molds are organisms that grow in damp places of houses and buildings after flooding. It can grow on walls, carpets, bathrooms, and floors. Mold produces tiny spores that can be inhaled by humans and cause asthma or respiratory diseases. Elderly children and pregnant women are the most vulnerable to mold-related illnesses. 

However, proper risk-eliminating strategies, for example, bleach and chlorine solution, regular inspection, and sufficient aeration, can eliminate this risk in flood-affected homes.

  • Mental health crisis:

A flood disaster can cause extreme psychological stress and emotional stress. According to NCBI, people who experienced floods suffered post-traumatic stress disorders, anxiety, depression, aggression, and psychological distress. To witness a flood destroying your home, hurting your loved ones, or drowning everything you love, can have devastating effects on mental health. According to a study by Dr. Noji, many flood victims reported hypertension, cardiovascular disease, leukemia, and lymphoma that may be stress-related. 

Therefore, assessment and routine checkup of the mental health of flood victims for possible signs of mental health issues is necessary. The circulation of mental health surveys and sessions with a professional mental health counselor to assess the mental health of flood victims is a convenient way of mitigating this risk.


Natural disasters can be overwhelming physically and mentally. It is not easy for flood victims to start again after losing their loved ones, home, and everything they had. It is difficult for depressed flood victims to focus and protect themselves from health risks and other hazards. However, the local government, risk-assessing institutions, flood-relief institutions, and research centers have given several guidelines and detailed instructions to help flood victims start a new life and protect them from health risks. Therefore, with the help of proper risk mitigation strategies and control measures, all these risks can be controlled and minimized to avoid the loss of resources and countless lives.