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GLOSSARY Of TERMS I I , generally drawn to show surface elevation for the crest of a specific flood, but may be prepared for conditions at a given time or stage. Flood An overflow on lands not nonmally covered by water and thllt are used or usable by rr>an. Floods have NO essentIal char- IIcterlstics: (1) the Inundation of land istOOlporary;and (2) the land Is adjacent to and Inundated by overflow from a river, a stream, an ocean, a lake, or other body of standing water. FloodStaqe The stage or elevation at which overflow of the natural banks of a stream or body of water begins In the reach or area In which the elevation is measured. Normally, a flood Is considered as any temporary rise In streamflow or stage, but not the ~ndingof surface water, that results In significant adverse effects In the vlclnity. Adverse effects may Include damages from overflow of land areas, temporary backwater effects In sewers and local drainage channels, creation of unsanitary conditions or other unfavorable sItuations by deposi- tion of materials In stream channelS durIng flood recessions, rise of ground water coincident with Increased streamflow, and other problems. Headless The effect of obstructions, such as narrow bridge open- Ings or buildIngs, that limit the area through which water must flow, raising the surface of the water upstream from the obstruc- tion. Le1t6ank The bank on the left side of a river, stream, or water course looking downstream. flood Crest The maximum stage or elavatlo~ reached by the waters of a flood at a given locatIon. Reference Point A numbered point identifyIng II specific locatIon used for correlating the data shown In varIous forms throughout the report. FloodPlaIn The relatIvely flat area or Iryw lands adjoining the chan- nelof a river. stream, watercourse, ocean, lake,orotherbody Of standing water which has been or may be covered by floodwater. Rlght&nk The bank on the right side of a river, stream, or w~ter course looking downstream. Flood Profile A gr3ph showing the rel~tlonshlp of w~ter surf~ce eleva- tion to location, the t3tter general Iv expressed ~s dlst~nce above mouth for ~ stream of water flowl ng in an open <;h~nnel, It Is 10-, 50-, 100-, ,., 500-YearFlood A flood having a 10, 2, I, o. .2 percent prob~blllty, respectively, of occurrence I, "Y ye~r o. " Ilvarl!lga frequency 01 occurrence " the order of once I, 10, 50. IDO, o. 500yedrs. " "