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with a mild slope leading to the wat:er, wit:h. sufficient space to maneuv~r the craft at the river's edge. Such still or low velocity water contributes to sedimentation. A mild slope to the water's edge requires cutt:ing t:he bank back to allow access, b'.lt it also widens the channel at 1:hat cross section, promoting a sudden slowing of .the flow and consequent deposition. As the length of thE: dis1:urbance to the river chann~l along the riverbank increases 1:0 accommodate the launch area, the shoaling problems increase due to imposed 'Velocity reductions over a longer length. A 10cally?referrEld boat launch location exists on the Gunnison River 'it a point where the drain from the easterly edge of the pro,?osed fish pond enters t,he Gunnison River. This location is about 2,900 feet downs.tream of the Highway 50 bridge, and 'ibout 4,100 feet upstream of the confluence with the Uncomp'ihgre River. The location is, at FEMA Flood Study station 35600. Three specific boat launch sites could be available (t."o riverside launch sites and a lagoon-type launch site). This general area has the following characteristics: o An existing~xcavated drain which could be enlarged and modified int,) an inlet or lagoon for a boat launch. o Proximity to an access road. o Proximity to a proposed parking area.. o Proximity to other recreation features. o Avoidance of disturbance to areas proposed for nature trails and wlldlife habitat. o Avoidance of conflicting use with other proposed park features. o Relative sta:)ility of the riverba.nk as shown by comparison 0 E photos from 1984 t:o cu.rrent conditions. Discussion:; with Bureau of Land Managemen1: (BLM) personnel indicated that their design of boat launch facilities on tile Dolores River took ad.vantage of the natural hydraul.Lcs of t:he river to a.ccommodate desired boat launch characte::istics. The BLM facilities were sited along convex side of ::iver curves and tangents where natural sandbars form. These areas provide easy access t:o the river and low velocit:l flows. However, t:hese types of areas also tend to have ve::y shallow water and tend to change as the immediate river hydraulics change. Significant flood events could easily al':er the entire facility, and even higher than normal flows conld cause maintenance problems. If sufficient avai:lable space exists to accommodate such changes, the problems may not be severe. However, if space is limited, and costly approaches are required, a more permanent and Yilliable facility should be sought. Discussion" with corps of Engineers personnel who have designed launch facilities on California rivers revealed that there is ill) reliable way of designing such facilities to consistently eliminate hydraulic problems, especially sedimentation and consequent shoaling. Several efforts at 19