This distinguishes them from flooding caused by high water. This is caused by rising water levels in rivers and streams and is more likely to be the result of large-scale weather conditions such as intense, continuous rainfall. Melting snow upstream also heralds possible flooding, sometimes days in advance. Other general conditions such as dry or frozen ground, in which rain cannot seep away, intensify such events.

Sometimes the effects of floods and heavy rainfall overlap: When small streams in narrow valleys and with small catchment areas are unable to drain sudden masses of water.

For the people whose cellars suddenly fill up, it does not initially matter whether it is heavy rain or flooding. Nevertheless, it is important to know the causes. After all, preventing damage is a joint task for local authorities and property owners. Heavy rain affects many departments in the state capital of Wiesbaden. In the course of climate change, extreme weather conditions are also becoming more frequent here. Various disciplines are working closely together here. At municipal level, measures for climate adaptation with regard to heavy rainfall are being developed and a basis for assessing areas at risk is being created, which can serve as a basis for planning and action. In addition, private precautions are an important element in protecting against the consequences of heavy rainfall - as they are for residents in areas at risk of flooding along rivers.