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<br />3&.1--10 <br /> <br />OOlGJ8 <br /> <br />WATER INFORMATION MANAGEMENT SYSTEM HANDBOOK <br /> <br />Step 2 - Using field measurements of discharge and/or station records, <br />bankfull and baseflow discharges are determined for the representative <br />station. The results of this step are: <br />QB = 173 cfs <br />QLl = 5.0 cfs <br /> <br />Step 3 - For all suitable stations bankfull discharge. is measured or <br />calculated using measured channel cross-section area, stage or width and <br />station records (as in step 2). <br /> <br />Step 4 - Using maps and/or photos, watershed area, area-weighted mean <br />elevation, or other watershed characteristics variables are measured for <br />the point(s) of quantification (see ex. 1). <br /> <br />Step 5 - Using the station data (area, etc.) for the representative and <br />all suitable stations (exhibit 1, rows a-m) and the values for QB <br />produced in steps 2 and 3, the following functional relation is developed: <br /> <br />QB = 11.06DAO.75 <br /> <br />Step 6 - Using the data produced in step 4 and the relation developed in <br />step 5, QB is calculated for the point(s) of quantification (Gold Creek <br />in this example): <br /> <br />DA = 42.4 mi2 <br /> <br />QB = 11.06DAO.75 <br />= 11.06(42.4)0.75 <br />= 183.8 <br /> <br />Step 7 - For channels which are unable to adjust their dimensions in <br />response to frequent flows only the duration and timing of bankfull <br />discharge remain to be determined. The duration is determined through use <br />of Common Steps 1, 2 (part 1), B, 9, 10 (QB only) and 11 (QB only), <br />sec. 36.2, appendix B. The timing of this discharge is determined by the <br />user and is based on local conditions as interpreted through professional <br />judgement. <br />