What is a 100-year flood?
The term "100-year flood" is misleading. It is not the flood that will occur once every 100 years. Rather, it is the flood elevation that has a 1 percent chance of being equaled or exceeded each year, based on a statistical analysis of streamflow records. Thus, the 100-year flood could occur more than once in a relatively short period of time, and since it is based on past flood history, this estimate can be wrong if the climate shifts. The 100-year flood is used by the National Flood Insurance Program as the standard for floodplain management and to determine the need for flood insurance. The 100-year floodplain corresponds to the area inundated by the 100-year flood, as determined by state-of-the-art hydraulic modeling and aerial topographic mapping.

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1. What is a 100-year flood?
2. Why is the City prone to flooding?
3. Why can't I build a flood wall around my property?
4. Can I remove fallen trees from the stream since they may cause flooding?