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Flooding and heavy rain

The beautiful and idyllic major river Rhine with its banks may also be malicious. Most of the residents do not only know romantic stories to tell about the river, but also something about ist threats.

Rhine River Flood Water

What we usually perceive as an idyllic scenario - the city of Bonn extending along the banks of the river Rhine - may well become a peril to life one day. Riparian owners do not only tell of the romantic stream, but of its threatening characteristics that become clearly perceptible every now and then. High water marks in 1993 and 1995 respectively were 10 meters above Bonn’s regular water level - which meant dramatic hours for local residents.

If you need help, call one of the following numbers:

  • Bonn Fire Department 0228 717171
  • Bonn Police Department 0228 150
  • River Police 0228 151410 or 0228 151411
In case of emergency, call 112 for the Fire Department and Rescue Service or 110 for the Police Department.

What to do in case of heavy rains in Bonn?

Heavy rainfall occurs when large amounts of rainwater fall within a short period of time in a confined area, especially in the summer months. There is no standard definition of the amount and duration of a heavy rainfall event. The German Weather Service, for example, specifies a quantity of 15 millimetres per square meter in one hour or 20 millimetres per square meter in six hours.

Backed-up water from the sewer, flooding from streams and rivers, but also water running off the surface away from floodplain areas in the middle of built-up areas can cause flooding of properties, buildings and traffic infrastructure and - last but not least - also endanger human lives!

The biggest challenge during heavy rainfall events is the short period of time between the storm warning, the start of the heavy rainfall and the flooding. During an event, there is hardly any time to take suitable measures to protect against flooding. Not least the flood events in July 2021 have shown that targeted preparation for heavy rain events, which are likely to occur more frequently in the future due to climate change, is essential.

Despite all the efforts that can be made, there is no one hundred percent protection against the consequences of heavy rainfall. Although the city of Bonn takes its duty of care towards its citizens very seriously, it cannot guarantee complete protection.

It is therefore all the more important that each and every individual takes precautions themselves.

Structural precaution

The civil engineering office and fire department are appealing to residents to take suitable measures themselves to prevent flash flooding from entering their homes.

This is because the public sewer system is not suitable for draining extreme amounts of rain. All citizens - including those who live on high ground - can be affected. Properties in the flood zone of a body of water are particularly at risk. Even the otherwise seemingly idyllic streams in Bonn can cause flooding during heavy rainfall.

The city therefore asks all citizens to pay particular attention to protecting their own buildings or homes. The costs involved are usually much lower than the potential damage.

Backflow protection, for example, offers protection against water backing up from the sewer. You can find more information in German on this sites:

Take care not to place any electrical installations in areas at risk of flooding. There is a risk of electric shock in the event of flooding.

Behavioral precaution

  • Check whether you live in an area at risk of flash flooding.
  • In the event of an incident, pay attention to the weather reports, local radio stations and any warnings from the fire department.
  • If in doubt, always get to safety first. Rescue people before saving property!
  • Help people in need of help to get out of the danger zone.
  • Do not go into flooded areas of the building. Doors and windows can no longer be opened due to the high pressure of incoming water. There is a danger to life! If existing electrical installations come into contact with water, there is also a danger to life from electric shock.
  • If the building fabric has been damaged by flooding, it should be professionally inspected.

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