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The peak discharge at Amity Dam, half a mile north of Prowers, was estimated at more than 100,000 cfs, and at Holly a slope-area measurement made by the Amity Land Co, gave a discharge of 136,000 cfs, The discharge at Holly in 1908 was slightly greater than during the flood of 1921, Flood of 1921, Above the mouth of the Purgatoire River no damaging flood occurred after 1894 until 1921, when the general storm that covered the state June 2-5 was concentrated in a series of cloudbursts between Canon City and Pueblo, These covered two separate areas, The larger area, roughly elliptical, extended from the northern boundary of Pueblo County to the top of the Wet Mountains near Beulah, a distance of 30 miles, and from a point a short distance above the mouth of Rush Creek nearly to Pueblo, a distance of 15 miles, The smaller area covered the south slop@ of the Pikes Peak uplift, which forms the northern part of the mountain valley, and extended from a point above Sl~aguay Reservoir to a point :3 or 4 miles south of the river, a distance of 25 miles, and from Oil Creek to Beaver Creek, a distance of 11 miles, The two areas together comprise 550 square miles, The progress of the storm down the valley cilused the msulting floods on many of the tributary streams to reach Pueblo at nearly the same time, bringing about them the greatest flood of record, The Geological Survey made an investigation of this flood, and published a detailed report, The peak discharge at Pueblo, as determined by slope-area measurement, was found to be 103,000 cfs, and the total discharge of the main flood at that point, less than 90,000 acre-feet After the flood of 1921 the State Legislature enacted the Conservancy District law, which enabled various interests in the Arkansas Valley to organize the Pueblo Conservancy District This district constructed a detention reservoir 10 miles above Pueblo, which was designed to reduce a discharge of 100,000 cfs, Channel changes in Pueblo were designed to carry, without overflow, a flood discharge of 125,000 cfs and thus to provide for a flood flow of 25,000 cfs originating below the reservoir. As floodS on the Purgatoire River are necessarily a source of floods on the Arkansas River below the mouth of that tributary, the flood of 1921 was not so greatly in excess of previous floods on that section of the river as the previOUS floods above the mouth of ths Purgatoire River. In fact the peak discharge of the flood of 1908 on the Arkansas River at Holly was 136,000 cfs, whereas the peak discharge in 1921 at Holly, when the Purgatoire River was not at flood stage, was only 120,000 cfs, Flood of 1929, The flood of the Purgatoire River, August 7, 1929, had a peak dischargE! of 52,800 cfs at the mouth and caused a peak discharge of 45,300 cfs on the Arkansas River at Lamar. The discharge from Purgatoire River was probably augmented by the rilinfall that was general over the Arkansas Basin, Flood of 1944, The flood of July 4, 1944, on Wilson Creek, a tributary of Oil Creek, causE!d a flood in the Arkansas River below the mouth of Oil Creek, At thE! Colorado Fuel & Iron Co.'s diversion dam, 3 milE!s west of Florence, the crest arrived at 12:45 a,m" July S, and lasted about 30 minutes, Its discharge was computed as about 19,000 cfs by the Colorado Fuel & Iron Co, As the flood proceeded downstream its peak was reduced to 9,720 cfs (4:15 a,m.) at the Portland gaging statiol1, 9 miles downstream, and to 5,980 cfs (8: 15 a,m,) at the Pueblo station, 24 miles farther downstream, 4.2.2 FOUNTAIN CREEK Following are descriptions of known large floods that have occurred on Fountain Creek in tile vicinity Colorado Flood Hydrology Manual 4.23 DRAfT