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2.4 damage and one person was killed in Williams Canyon. Hailstones were found to be 11 inches in circumference (Reference 3). In May 1894, a rainstorm of several days duration caused flooding in the area; however, flood heights were not as high as they could have been had much of the precipitation not fallen as snow. Fountain Creek, Ruxton Creek, and Williams Canyon all flooded. Canon Avenue was described as a mountain torrent with hundreds of tons of rock washing down (Reference 4). e A cloudburst over Williams and Waldo Canyons in May 1947, caused flooding on Williams Canyon and Fountain Cree!k. Many small br idges were washed out, and the debris created dams that eventually broke and caused further damage (Reference 3). ., A correlation between the elevations of previous floods and the elevations of possible future floods as prese!nted in this study is difficult to determine because of changes in the stream channels as a result of high flows and subsequent deve!lopment. At Fountain, Colorado, approximately 25 miles downstream from Manitou Springs, a 40-foot-long bridge spanning Fountain Creek. was washed out in a flood in 1902 and was replaced by one 70 fe!et long. Succeeding floods have widened the channel even more so that the bridge span now exceeds 200 feet. Due to the changing channel capacities, an estimate of the recurrence intervals of palst floods would not be valid (Reference 4). Photographs of potential flooding at Manitou Springs are shown in Figures 2 and 3. Flood Protection Measures - The flood-carrying capacity of the streams has been increased through channelization in many areas. For this to be an effective flood protection measure, the entire stream length in flood-prone areas must be channelized to the extent necessary to carry low- frequency flows. Because this is not the case in Manitou Springs, the channelization that exists is not sufficient to protect the city from floods of the selected recurrence intervals in all areas. The city has enacted ordinances that are directed at the reduction of flood hazard. These ordinances specify that drainage be designed to reduce exposure to flood hazard and not to subject other property to flood hazard and that new construction be reasonably safe from flooding. The city also requires that new and replacement water- supply and sanitary sewage systems be designE~d to minimize or eliminate infiltration of floodwaters. There are no structural means of flood protection, such as dams or levees, in the city. .. - 6