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<br />I <br /> <br />Slope-Area Method <br /> <br />I <br />I <br /> <br />The slope-area method is used to theoretically determine the <br />instantaneous peak discharge for an actual flood event. The method, <br />described by Dalrymple and Benson (1967), requires an analysis of the <br />geometry of several cross sections in a reach of stream channel, <br />evaluation of the drop in water-surface profile in that reach as <br />defined by high-water marks, and estimates of the channel roughness <br />within each reach between the cross sections. Analysis of these <br />factors and the application of a uniform-flow equation results in the <br />peak discharge for the flood in question. <br /> <br />Culvert Method <br /> <br />I <br />I <br />I <br />I <br /> <br />The relation of stage to discharge at the approach section to a <br />standard culvert can be calculated by considering the approach section <br />properties, culvert geometry, and by applying the principle of <br />conservation of energy as outlined by Bodhaine (1968). <br /> <br />Parshall Flume and Modified Venturi Flume <br /> <br />I <br />I <br /> <br />The stage-discharge relation for a Parshall flume is determined <br />by its physical characteristics, particularly throat width. Ratings <br />for Parshall flumes may be found in numerous hydraulic texts such as <br />Chow (1964). <br /> <br />DATA FORMAT <br /> <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />Modified Venturi flumes described by Palmer and Bowlus (1936), <br />cause flow at critical depth within the flume throat. Therefore, a <br />relation between water depth in the throat and discharge can be <br />developed by using Bernoulli's theorem. <br /> <br />All significant rainfall-runoff data collected through September <br />1971 by the statewide network of gages are included in this compilation. <br />It should be noted, however, that in numerous instances a rainstorm <br />was recorded, but due to its distribution over the basin, no associated <br />runoff was observed. Conversely, significant runoff events have been <br />recorded and no appreciable precipitation observed. Data are not <br />included for ei~her of these cases. <br /> <br />8 <br /> <br />I <br />I <br />I <br />