Laserfiche WebLink
<br />to produce record floods, More than 14 in of rain fell near Palmer Lake and near Larkspur In about <br />4 h, Over 12 In was reported near Castle Rock in the same time [63]. <br /> <br />East Plum Creek near Castle Rock crested at 126,000 fj3/s during the late afternoon of June 16, <br />The unit runoff at this site was 1,170 ft'/s per mi', from a 108-mi' drainage, The Plum Creek <br />gauging station near Louviers, about 12 mi downstream from Castle Rock, was destroyed during <br />the flooding, but observations indicated that the flow at that point increased one thousandfold In <br />less than 3 h, from about 150 to 154,000 ft'/s, The recession was also quite rapid, with a peak <br />of 988 ft'/s measured by waders only 18 h after the peak, Estimated velocities were 20 to 22 <br />ft/s during the peak flooding, <br /> <br />The PMP for this basin was determined by using HMR 55 [2] procedures. Table 37 presents the <br />depths for various durations used to determine the Plum Creek PMF. <br /> <br />The values in table 37 compare favorably with the 14 inches in 4 h reported, <br /> <br />350 <br /> <br />300 <br /> <br />250 <br /> <br />200 <br /> <br />I <br /> <br /> <br />HISTORIC PEAK ~ 126000 CFS, I <br />38.4 % OF PMF PEAK -r---- <br /> <br />150 <br /> <br />100 <br /> <br /> <br />50 <br /> <br />o <br /> <br />o <br /> <br />PMf PEAK - 328000 crs <br />PMf 24 HOUR VOLUME - 123580 AC FT <br /> <br /> <br />EUREAU OF RECLAMATION <br />PHF COMPARISON STUDY <br />PLUM CREEK NEAR CASTLE ROCK COLORADO <br />LAG ~ 3.31 HR CHERRY DUH <br />PMP BASED ON HMR 55 <br /> <br />HISTORIC FLOOD ON JUNE 16 J565 PEAK - 126000 CFS <br />KLB UV1/8" <br /> <br /> <br />6 12 18 24 313 <br />TIME FROM BEGINNING OF RRINFRLL (hrs) <br /> <br />42 <br /> <br />36 <br /> <br />Plate 47 - Computed PMF hydrograph and historic flood peak for Plum Creek near Castle Rock, CO. <br /> <br />85 <br />