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2 below. The methodology for estimating the peak discharges shown in Table 2 was the same as described above for the flow estimates in Table I. Table 2 Summary of Additional Peak Dis(:haJrges Estimates Vicinity of Buffalo Creek, Colorado CV\ Esti~ p€, Stream Name Location Flow - Sand Draw 2,500 ft U/S of mouth ~~ Sand Draw 6,400 ft U/S of mouth 4,9 Sand Draw 9,500 ft U/S of mouth 2,2 Sand Draw 10,000 ft uls of mouth 2,2 Sand Draw 10,800 ft U/S of mouth 1,( Sand Draw 12,800 ft U/S of mouth 4( Sand Draw 12,900 ft U/S of mouth 3( S/JrinK Gulch 1,000 ft uls of mouth 5,: TCB tlated a]( (ds) 00 --.- 00 .00 .00 100 )0 )0 ~OO Contributing Drainage Unit Discharge Area (cfs/sq mi) (square miles) -- 1.55 4,774 -- 1.00 4,900 0.47 4,681 0.45 4,889 - -- 0.33 3,030 ---- 0.12 3,333 0.08 3,750 -.-.. 0.95 5,474 -- The July 12 estimated flow values are far greater lh,m the FEMA lOO-year values. There is obviously some question as to the validity of the FEMA discharges that are reported in the Flood Insurance Study. The FEMA flow values for Buffalo Creek itself appear to be questionable. FEMA may conduct a re-study of the Buffalo Creek floodplain information at some time in the future. A streamflow gaging station is located on the South Platte !River at South Platte (downstream of the confluence with the North Fork) recorded the flash Hood event. However, it did not accurately record the peak stage or discharge. A stream gage on the North Fork just upstream of its confluence with the South Platte River was discontinued approximately 15 years ago. The highest recorded peak discharge on the discontinued gage was about 2,100 cfs in 1949. When estimates of flows at the discontinued gage site are available, they will be provided. The USGS will be looking into how to retrofit the South Platte gage, and possibly how to re-establish the discontinued North Fork gage, so that future flow estimates during large floods may be more reliable. 7