Laserfiche WebLink
<br />GLOSSARY OF TERMS <br /> <br />Channel - A natural or artificial ~ater course of perceptible <br />extent ~ith definite banks to confine and conduct <br />continuously or periodically flo~ing ~ater. Channel flo~ <br />is that ~ater ~hich is flowing ~ithin the limits of the <br />defined channel. <br /> <br />Flood - Water from a river, stream, water course, lake or <br />other body of standing ~ater, that temporarily overflows <br />the boundaries ~ithin which it is ordinarily confined. <br />Flood Crest - The maximum stage or elevation reached by the <br />waters of a flood at a given location. <br />Flood Frequency - A means of expressing the probability of <br />flood occurrences as determined from statistical analysis <br />of representative streamflow or rainfall and runoff <br />records. The frequency of a particular stage or <br />discharge is usually expressed as occurring once in a <br />specified number of years. The 10-, 50-, 100-, and 500- <br />year frequency floods have an average frequency of <br />occurrence in the order of once in the number of years <br />indicated. <br /> <br />flood Hazard Areas - Areas susceptible to flood damage. <br />FlOOd Peak - The highest stage or discharge attained during a <br />flood event; also referred to as peak stage or peak <br />discharge. <br /> <br />flood Plain - The relatively flat or lowland area adjoining a <br />river, stream, watercourse, lake, or other body of water <br />which has been or may be covered temporarily by flood <br />water. For administrative purposes the flood plain may <br />be defined as the area that would be inundated by the <br />lOO-year flood. <br />Left or Right Stream Bank - The left or right bank of the <br />stream looking downstream. <br />PerChed Channel Flow - A condition where the flow elevation <br />in the outer portions of the flood plain is higher than <br />the flow elevation in the main channel. This condition <br />occurs when a secondary channel receives inflow from some <br />location upstream and maintains a flatter slope than the <br />main channel. <br /> <br />Reach - A hydraulic engineering term used to describe <br />longitudinal segments of a stream or river. <br /> <br />" <br /> <br />" <br /> <br />Runoff - That part of precipitation, as well as any other <br />flow contributions, whiCh appears in surface streams of <br />either perennial or intermittent form. <br /> <br />Stream - Any natural channel or depression through which <br />water flows whether continuously, or intermittently, <br />including modification of the natural channel or <br />depression. <br /> <br />Structure - Anything constructed or erected, the use of which <br />requires a more or less permanent location on or in the <br />ground. Includes but is not limited to bridges, <br />buildings, canals, dams, ditches, diversions, irrigation <br />systems, pumps, pipelines, railroads, roads, sewage <br />disposal systems, underground conduits, water supply <br />systems and wells. <br /> <br />Valley Cross Section - A plotting of the topography of a <br />stream channel and adjoining landscape as viewed <br />perpendicular to the flow in a downstream direction. The <br />plotting represents a specified location within a <br />designated stream reach. <br /> <br />Water Surface Profile - (This term is synonymous with Flood <br />Profile) - a graph showing the longitudinal relationShip <br />of the water surface elevation of a flood event to <br />location along a stream or river. <br /> <br />watershed - A drainage basin or area which contributes to <br />runoff and transmits it, usually by means of strca~s and <br />tributaries, to the outlet of the basin. <br />