Flood, 100-Year : A 100-year flood does not refer to a flood that occurs once every 100 years, but to a flood level with a 1 percent chance of being equaled or exceeded in any given year
US Department of the Interior, US Geological Survey USGS, Water Science Glossary of Terms, http://ga.water.usgs.gov/edu/dictionary.html (Some of this information is courtesy of the Nevada Division of Water Resources - the detailed water glossary at VA, USA 2009. http://water.nv.gov/programs/planning/dictionary/) , (ND/ Flood - Amer) {491}
