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. . . which is cleaned and maintained by the town on an as-needed basis. The flume seems to have adequate stability and is in good working condition. The Town and County do not seem to be particularly concerned about the stability of the wooden flume. IV. ALTERNATIVE PROJECT PLANS Two different methods of providing drainage improvements and flood protection for the Town of Creede were investigated. They are as follows: I. Provide an overflow channel (spillway) across the top of the tailings pile and stabilize the pile to help prevent embankment failure during a high flow event. 2. Remove all or a portion of the tailings pile and remove the existing steel pipe to create an open channel in its place. The two methods were evaluated based on the criteria of engineering constraints, environmental constraints, project costs, construction methods, and operation and maintenance. Overall, alternative 2 (removal of the tailings pile) would provide the most reliable method of flood control for the town. However, alternative 2 would be much more expensive to construct, may require extensive permitting, could adversely affect the downstream water quality (temporarily), and may involve the disposal of hazardous materials. A project of this scope is beyond the capacity of the Town of Creede, Mineral County, and the Colorado Water Conservation Board. A future project of this scope may have to be considered by the EP A or other agencies. Alternative I could provide reasonable flood protection for the town without all of the potential costs and other considerations associated with alternative 2. Based on the above criteria, alternative I was chosen as the most feasible approach to mitigating the existing flood hazard on West Willow Creek. V. RECOMMENDED PROJECT PLAN Hvdrologv and Hvdraulics The drainage area for Willow Creek at Creede is approximately 35 square miles, and the published 100-yr flow value is 1120 cfs. Based on that information, a unit discharge was assumed to be 32 cfs/sq. mile for West Willow Creek at the design location. The drainage area upstream of the design location was planimitered to be about 12.5 square miles. Therefore, based on the assumed unit discharge, the lOO-yr flow on West Willow Creek was estimated to be 400 cfs at the design location. The hydraulic design of the recommended overflow channel was determined by using the computer program entitled FlowMaster™ (Haestad Methods). The overflow channel was 3