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<br />• <br />' Start of field measurements = 1030 <br />~ 1030 - 4 hours = 0630 ~ GH = 4.285 feet <br />~ 1030 + 4 hours = 1430 ~ GH = 4.280 feet <br />d = 0.005 feet <br />Assuming an average river width of 150 feet, <br />150 ft. (0.005 ft)(4.6 mi)(5280 ft/mi) = 0.6 cfs <br />ours sec/hr) <br />Since river stage was decreasing, it would be expected that the <br />downstream discharge would be less than the upstream after pas- <br />sage of time. Thus, using this method, 0.6 cfs would be sub- <br />tracted from the total difference between the first and last <br />stations on that day. However, a similar analysis for 30 August <br />shows a change of 5.2 cfs. This much additional inflow would <br />have to be accounted for via ground-water discharge. This seems <br />unlikely. But as discussed above, with the available data, there <br />• is no precise way to determine the cause of small stage charges <br />at Station i, aad therefore, chaunei storage changes cannot be <br />included in this analysis. <br />Since it is likely that channel storage change is a <br />small, but possibly very important component of the overall floco <br />changes, an alternate method is recommended if additional field <br />work is performed. The installation of a second recording gage <br />at Station 5 would allow a more precise determination of inflow <br />and outflow at all times. This .should be coupled with a rigorous <br />time of travel dye study over the reach of interest. Also, one <br />additional day's discharge measurements will help corroborate <br />the results. Since it has been identified that the exchanges <br />were occurring between Stations 2A and 5, additional study should <br />be focused on .this 2.2 mile reach. <br /> <br /> <br /> <br />4-10 <br />