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were noted to determine the approximate age of the tree and depoeit). As a general guide in this study, trees that had been cut (within about the last month) along the Pikes Peak railroad right-of-way along Ruxton Creek were used to estimate tree diameter and age relations for several apruce (believed to be Englemann spruce> trees. For example, a 2-inch spruce had 10 annual growth rings;~a 4-inch spru~e had 35 annual growth rings, and; a 15-inch spruce had 70 annual growth rings. Theae can be used to estimate the relative age of spruce trees on the flood deposits (roughly, 1 inch of diameter represents 5 years of growth); hence, an approximate time since the deposits were formed. In mountain channels not sub~ect to significantly out of bank flows, channel conditions are much different. These channels generally ehow very little evidence of sediment moveme~nt and channel erosion or depoeitional features. Bed material show no evidence significant movement, channel banks are well vegetated with grass and m6~s (Figure 2B). Bouldere and bedrock ~ust a~ove the water level generally are covered extensively with moss and lichen indicating that flood waters have not disturbed the channel for a long time. Vegetation, even those growing immediately next to the chann~l do not show any, or only minimal, evidence of scarring from flood debris. There is no vegetative flood debris lodged upstream from obstructions. The height ~f the flood deposits and scarred trees provide an indication of the approximate flood depth; widths can be me~sured in the channel at these sites ,and to then estimate mean flo~d depth. From these, approximate cross-sectional area can be estimated. Then methoda can be use to estimate velocity (extensive work has shown that a reasonable mean flood velocity in these mountain channels is 10 feet per second and was used for this investigations) and peak discharge. A mean velocity of 10 feet per second ia conservative (overe~timated) for recent flowe. Onsite investigations to locate flood erosional and depositional features were conducted in Ruxton Creek (the atream considered to have the greatest flood hazard), Williams Canyon, Fountain Creek (and tributariea upstream from Manitau Springs>, Sutherland Creek, and Camp Creek (Figure 1). For the paleoflood investigations in this study, channels were inspected to indentify erosional and depositional features (indicatore) of ~ut of bank flooding. Use of the paleohydrologicj techniques d~scribed above has allowed for the estimation of 3 general level of floods; recent (or frequent), in the last 10 yeare; medium, in the laet 30 to 100 years, and; th~ maximum flood, greater than 100 year~s. These onsite inveetigations are representative of flow conditions for a reach of channel. These observations are discussed below for each creek, starting with the moat downatream baein. Eetimatea of width,~depth, discharge, and approximate time since a flaod for recent, medium, and the largest observable flood are shown for the sites investigated on Figure 1. These investigations were only made in natural stream channels upstream from urban development. because this development disturbs the flood deposits. Time was not available to visit other tributaries, such as Cheyenne and Bear Creeks, but these investigations are believed to provide an understanding of the local flood hydrology. ~~.