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the channel to determine the elevation limit of signific~nt flood evidence. Sutherland Creek Sutherland Creek has a drainage area of 5.37 square mil~s and is steep in the middle part of the basin. Downstream from about 6,600 feet the channel appeare to have been modified because of urban development and was not investigated. A small (estimated 0.4 square miles) left bank tributary at an elevation of 6,380 feet is t}~pical o£ small drainages at thia elevation. The channel is•5 feet wide and flood debris ia 2 feet above the streambed. The lack of vegetation in the channel bottom indicates frequent flowe. This suggests recent flows of about 100 cubic feet per second. - At an elevation of 6,500 feet, Sutherland Creek has terr.aces and gravel bars about 30 feet apart and with tops about 8 feet ~bove the c~~nnel bed. These are well vegetated with 2 inch diameter-scrub oak (~ slow growing tree), dense brush, and near completely lichen covered boulders indicating a maximum flood. The peak discharge is Eestimated to be about 2,400 cubic feet per second. The channel ~ahich has scoured banks is about S feet wide and 2 feet deep, indicates a recent (within the laet 2 to 3 years) peak discharge of 100 cubic feet per se~,~n~. At an elevation of 6,640 feet, ~ust upstream from the security entrance to Crystal Park Community, the channel is filled wit~ 8 to 10 feet diameter boulders in a debris-flow lobate form (although somewhat washed out by subsequent water flows). The deposit is cov~=red with lichen and moss and there are many large trees growing on th~ deposit indicating it is several hundred or more years old. A v~ry large event would have been required to transport these boulders. About 100 feet upstream, the recent channel is 3 feet wide and based on lack of vegetation on small in channel deposits the depth is about 2 foot. Greater than this depth channel bouldere are moss covered and the banks are well covered with grass. Recent peak discharge (ir- the last 2 to 3 years) is about 60 cu~iic feet per second. On the right bank there is a 10 foot by 20 foot gravel bar. The width is 30 feet and its top surface is 4 feet above the streambed. There are no flood deposits higher in the channel. The surface of the gravel bar has several 2 to 4 inch diameter spruce trees and moderate brush cover suggesting the deposit is about 10 to 20 year~ old (these probably correspond to the 1965 flood). The peak discharge for this maximum flood (note that in this caae the maximum flood occurred about 10 to 20 years ago) is estimated to be 1,200 cubic feet per second. There are large debris flow deposits from here upstre~m. The debris flow channel is 50 feet wide and 10 feet deep. Mean velocity and peak•debris-flow discharge can not be estimated for a debris flow based on the available information; widths and depthe are provided as an indication of the size of the flow. Exposed slopeg on the steep ewitchback road show very little if any rill eroeion. The elevation of the switchbacks vary from 6,650 to 6,900 feet. This would suggest that intense rainstorme are infrequent at and above this elevation. 4.