Search results
Results from the WOW.Com Content Network
The term 100-year flood indicates that the area has a one-percent chance of flooding in any given year, not that a flood will occur every 100 years. [ 2 ] Such maps are used in town planning , in the insurance industry, and by individuals who want to avoid moving into a home at risk of flooding or to know how to protect their property.
Theoretically a 100-year flood has a 1 percent chance (1/100 = 0.01 or 1 percent) of occurring in any given year and a 500-year flood has as a 0.2 percent chance (1/500 = 0.002 or 0.2 percent) of occurring in any given year. [12] However, these expected flood elevations actually occur more or less often than expected. [13]
Ten-year floods have a 10% chance of occurring in any given year (P e =0.10); 500-year have a 0.2% chance of occurring in any given year (P e =0.002); etc. The percent chance of an X-year flood occurring in a single year is 100/X. A similar analysis is commonly applied to coastal flooding or rainfall data.
The county is currently using 500-year flood maps to indicate areas where residents should be ready to evacuate. "We are using the 500-year flood plain maps as kind-of a guide.
A day after Hurricane Ian made landfall in southwest Florida as a Category 4 storm, Florida Gov. Ron DeSantis said Thursday that the storm surge that came with it was “basically a 500-year flood ...
For premium support please call: 800-290-4726 more ways to reach us
A floodplain or flood plain or bottomlands [1] is an area of land adjacent to a river. Floodplains stretch from the banks of a river channel to the base of the enclosing valley, and experience flooding during periods of high discharge. [2] The soils usually consist of clays, silts, sands, and gravels deposited during floods. [3]
Historically, at least in the US, works were built to certain design specifications (for example, the 100-year flood, or 1% flood). In instances where the design specifications were exceeded (in the case of a 150-year flood, etc.), they failed, thus causing catastrophic loss in overdeveloped floodplains (White et al., 1958).