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GLOSSARY OF TERMS "000 An overflow on Illnds not normally covered bywllterand th"'T are ~sed or uSllble by man. Floods have two essential character- istics: Thainundatlonof land istEfllporarY;!Indthe land is adJacent to and Inundated byoverflowfrCtl'la river or stream or an ocean, lake or other body of standing water. Normally a "flood" is considered as any temporllry rise In stream flow or stage, but not the pondlng of surface water, that results in slgnlfic",nt ",dverse effects In the vicinity. Adverse effects m",y Include damages from overflow of land arees, temporery backwater effects In sewers end local drainage Chllnnels, erection of ~nsanit"'ry conditions or other unfavorllble situatIons by deposition of materiels in stream channels during flood recessIons, rise of groundwater coIncident with Increased stream flow, and other problems. Flood Crest The maximum stage or elevation reeched bythe....a-tersofa flood <It a given location. Flood Phin Thareidtivelyfilltdrador lowiandsadjoinlngfhechan- nel ofarlvor, stream or water course or ocean, lllke, or other body of standing water, whiCh has been or may be covered by floodwater. Flood Profile A graph showIng the relationShIp of wator surface elevation to loc"tion, the latter generally expressed as distance abovemo uth fore stream of water flowing In an open channel. It isgener<llly drllWn to show surface elevation for the crest of II specific flood, but may be prepllred for conditions llt a given time or ~tage. " Flood Stage The stage or eleVlltlon llt WhiCh overflow of the natural banks of a stream or body of water begins In the reaCh or area in whiCh the elevation is meas~red. He"dLoss The effect of obstructions, such as narrow bridge oJenings or buildings th"t limlttne"rea through which w"termustflow, I' aislng the surface of the water upstream from the obstruction. Intermediate Regional FlOOd A flood having a one percent probaOllity or an avarage frequency of OCCUrrenCe in the order of once In 100 years <llthough the flood may occur In any year. It Is basod On statistical analyses of stream flow records availllble for tho waterShed and analyses of raln- fall en<l runoff ch"racterlstics In the "goneral region of the watershed." 1 left Bank The bank On the left side of a river, STroam or water courso, looking downstream. Low Steel (orUndorcIGarance) S"'l"underclearancG." Right8<lnk n.., b"nko;, tr06 right Sideuf" riv,,r, sl-,,,,,m or water cours..,lookingdownstre<l'l1. Standard Project Flood ThO flood that may be eXhocted from the most severo com- bination of meteorological and hydrologicdl conditions that <lre considered re~sonably CharaCToristic of the geugraphlcal area In "