Table of Contents
- Heavy Rain Can Pour Down Almost Anywhere
- Communities Inform About Endangered Areas
- Short Warning Times Make Quick Action Difficult
- Never Step Into the Flooded Basement
- Prepare the Basement Before Heavy Rain
- Secure the House Against Backflow
- Who Pays If Heavy Rain Causes Damage
- Avoid Disputes with Insurance
- Prepare Basement Windows
- Clean Gutters Regularly
- Heavy Rain Entry Point: Underground Garage
- Checklist for Protection Against Heavy Rain
Heavy Rain Can Pour Down Almost Anywhere
- What not to do in heavy rain <unk> and how to protect your house and basement
Those living near the Danube or Rhine rivers have already dealt with the issue of flooding. However, even far from these major rivers, basements can flood due to heavy rain. It can pour heavily in Germany and cause significant damage. Small rivers can suddenly swell into raging torrents; but also sealed surfaces, a slope location, or a depression can bundle the rain into a flood wave that overwhelms local drainage systems – or presses directly into the house. With climate change, such weather events are likely to become even more severe in the coming years.
Communities Inform About Endangered Areas
By entering the name of your community and "heavy rain map" into your internet browser, you will usually find an interactive map showing the path the water takes. This allows you to estimate how endangered your own house is. North Rhine-Westphalia is a model: The state has compiled all municipal maps on a website, but community maps are often more detailed.
Short Warning Times Make Quick Action Difficult
Unlike river flooding, it's difficult to predict where heavy rain will cause floods. Therefore, it's important to take long-term precautions. Where it makes sense to place sandbags in front of the underground garage entrance or basement windows in case of emergency, these should always be readily available. Additionally, the weak points of the house should be identified and repaired (see below).
Never Step Into the Flooded Basement
The urge to quickly save something should not be acted upon lightly. In early May, a man died in Hausen (near Würzburg) from an electric shock when he entered his flooded basement. As soon as water reaches electrical outlets or devices, there is an immediate risk of death. It may be worthwhile to turn off the power to the basement as a precaution before the storm.
The water pressure can also be tricky: If the water is already standing in the basement, doors may not be able to be opened against the water pressure.
Prepare the Basement Before Heavy Rain
Valuable items should not be stored in the basement. Electrical outlets should be located upstairs – and no multi-outlet strips should be hanging down. Oil or half-open paint cans can also backfire if water gets into the basement. A basement that can get wet should be painted or tiled waterproof, rather than wallpapered.
Secure the House Against Backflow
When it rains cats and dogs, the sewage canals fill up. Usually, rainwater and wastewater flow together into a sewage system. If this is overloaded, the wastewater cannot flow away, presses back into the basement – and can even come out of the drains higher up in the house. Therefore, the house must be properly secured with a backflow preventer or a lift station. This is usually also required by law.
Despite reports from insurance experts that in the majority of houses they inspect, this backup prevention is not sufficient, the reverse flow of wastewater during heavy rain is by far the most common cause of damage. Even the best protection is useless if it is not maintained regularly. A common cause when the flap does not close properly is litter thrown carelessly into the toilet. Sanitary napkins, diapers, or food scraps can get stuck on the flap.
Who pays if heavy rain causes damage
Damage in the basement is regulated by household and residential building insurers. The former for furniture and items, the latter for the building. However, only if so-called elemental damages are also insured. Some insurers exclude damage from backup even then, warn consumer centers. So better check the fine print!
Avoid trouble with the insurance
If the house is flooded, residents should do what is possible to keep the damage to a minimum - provided it is safe (see above). That's what insurers demand. But first, one should definitely document the damage with photos and videos, otherwise it might become difficult with the reimbursement. It also makes sense to document the maintenance of the backup protection.
Prepare basement windows
The light shafts of basements are often a weak point: They usually have no water drainage, a small pool forms in the shaft, from which the water presses against the pane. Either the panes must be pressure-resistant or the light shaft is protected with flaps or walled up.
Clean gutters regularly
Gutters are often not cleaned and leaves and moss accumulate. Many consider this unproblematic, but water often finds ways into the roof, onto balconies or other places where it can press into the house. Sometimes there are also old drains in old houses that direct water from outside into the house drain. If the backup then works as desired, this water cannot drain away and overflows into the house through the drains.
Stormwater entrance to underground garage
Recently, the underground garage of a police station in Idstein, Hesse, filled up so quickly that the garage door could no longer be opened. In inner cities, new buildings are increasingly equipped with underground garages. The access ramp is often an entrance for heavy rain, as the small catchment ditch at the entrance is not designed for large amounts of water. It becomes dangerous when an electric car is charging at the charging station - and possibly incoming water sets the current.
In the underground garage as well, one should not endanger oneself. The Flood Competence Center recommends not driving the car out if the water level reaches ten centimeters.
Checklist for protection against heavy rain
Those who want to protect their single-family home against heavy rain should first check the risk using municipal maps (see above). Then there are useful checklists that allow all attack points to be systematically worked through. Particularly suitable are the e-book "Storm Damage Building Check" (as PDF) of the consumer centers and the information of the Flood Competence Center.
Sources: Consumer Center, Flood Competence Center (HKC), Federal Ministry for the Environment and Consumer Protection (BMUV), tagesschau.de, Hessenschau, R+V
- Despite the precautions, heavy rain can still cause flooding in basements, even in countries like Germany, where flooding is not typically associated with major rivers.
- Regular maintenance is crucial for the proper functioning of a backflow preventer, as common causes of failure include litter thrown carelessly into the toilet, such as sanitary napkins, diapers, or food scraps.
