Release of pollutants due to flooding
Heavy rain, melting snow, other extreme weather conditions and human intervention in the course of watercourses all contribute to the flooding of streams and rivers. If the precipitation cannot seep into the ground sufficiently or quickly enough, flooding occurs. However, it is not only river water that flows through the floodplains. The water masses also carry a lot of garbage and thus pollutants with them, which they pick up on their way. In areas affected by flooding, toxic chemicals and other substances or pathogens can enter gardens, cellars and homes.
Chemicals & waste
Flooding can release chemicals, pesticides and hazardous waste from industrial plants, warehouses or farms into the surrounding area. Chemicals stored in your home or on your property, such as cleaning agents, paints or pesticides, are another source of danger. These can also be absorbed by the floodwater and mix with the pollutants. The closer the source of the pollutant is to your living space, the higher the concentration in the flood water can be. All the substances absorbed by the water can get into the air, worsen the air quality and be absorbed by your body through your breathing.
Mold spores
After a flood, the humidity in affected buildings and areas also rises sharply, which can cause mold growth. If the building has been soaked by the flood and this moisture is not completely removed, dangerous mold can sometimes grow. Areas where water can "hide" are particularly problematic, such as wood paneling, wallpaper, poorly drying insulation materials, lightweight walls, thick carpeting or upholstered furniture.
If the mold spores get into the air, they can penetrate the occupant's body via the respiratory system and cause breathing problems. People with allergies or respiratory diseases in particular may experience symptoms such as mucous or irritated airways, a feeling of having a cold, headaches, reduced performance or a generally impaired sense of well-being. Depending on the type and duration of exposure to mold, allergic reactions, asthma attacks and chronic bronchitis are also possible. It is therefore advisable to check all materials that do not dry quickly after a flood and dispose of them if necessary. Check the level of humidity in the rooms with an air measuring device such as the air-Q to detect increased humidity and act accordingly.
Increased particulate matter pollution due to flooding & high water
River water can also contain building rubble, materials from industrial plants or power stations as well as residues from road traffic, which then end up in your garden or living space with the water.
Sediments & debris
Sediments such as heavy metals or other pollutants often accumulate in estuaries. These are washed up by the flood and carried further. When the water recedes after flooding, it leaves these sediments and other debris behind. The drying process of these materials can lead to increased dust pollution due to particulates lead to increased dust pollution. The particles are carried on the wind and transported into homes as fine particles.
Construction work & cleanup
Significant amounts of dust can also be released during restoration and clean-up work after a flood, which can have a negative impact on air quality.
Biological contamination after a flood
Floods not only wash up inorganic material. Organic materials are also found in the floodwaters and continue to decompose here.
Animal carcasses & plant remains
Flooding can lead to the death of animals and the destruction of plants. The decomposition of these organic materials can release gases such as putrefaction or rotting gases and particles that affect air quality. Biological impurities are found in alluvial sludge in particular.
Mushroom growth
Damp conditions also promote the growth of fungi, whose spores can become airborne and pose a health risk.
Transportation & energy supply
Traffic jams due to the traffic obstructions caused by the floods and clearing work using clearing vehicles lead to an increased enrichment of the air with exhaust fumes.
Faults & emissions
Floods can lead to traffic congestion and increased use of emergency generators. This increases emissions from vehicles and generators and significantly worsens air quality.
Flood checklist: risks & recommendations for action
- Wear sufficient protective clothing such as gloves and breathing masks during the clean-up work to protect yourself from the harmful substances.
- Follow the instructions of the public health department regarding the drinking water supply and have your own well water tested before using it as drinking water.
- Before you put your electrics, heating system etc. back into operation, you should have them checked by a specialist.
- Check the air quality with an air measuring device such as the air-Q to rule out increased levels of pollutants in your rooms or to identify the source. Targeted ventilation is then possible.
Overall, floods and similar natural disasters can have complex and diverse effects on air quality. These effects can be caused both directly and indirectly by changes in living conditions and increased human activity.
