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<br />lower tailings pile to the stream below. Numerous large thrust blocks, support blocks, and a <br />concrete stilling basin would be required. It was considered important to continue to pass low <br />flows into the current steel pipe and pipe "waterfall" for aesthetic reasons. Two scenarios were <br />envisioned to accomplish this. Low flows could still be passed through the current flume and <br />pipe systems while only flood flows could be directed to the bypass system. Alternatively, all <br />flow could be directed into the new system which could pass low flows to the steel pipe at the <br />location where the new system would intersect the old system. This would be slightly more <br />expensive, but would allow for removal of the deteriorated wooden flume and drop that may <br />soon cause a failure. It was estimated that the project would cost at least $900,000. However, <br />extensive design will still be required to determine the most appropriate system, materials, and <br />construction methods given the difficult conditions. <br /> <br />Micro-hydro power generation was also briefly considered for the flood bypass system. Power <br />generation could potentially help offset construction costs or costs for potential treatment of <br />water from the Nelson Tunnel. However, due to the small flow in West Willow Creek during <br />winter months, it appeared that a micro-hydro power project would not be cost effective. <br /> <br />It will be very important to ensure that large sediments and debris will not enter a closed flood <br />bypass system. A design for three "grizzly" gratings was proposed to protect the flood bypass <br />system. This project should be considered as part of any flood bypass project, and would raise <br />the cost of the project by about $30,000. <br /> <br />Amethyst Mine Debris Protection <br />A new "grizzly" grating was also proposed for the area upstream of the culvert at the Amethyst <br />Mine to protect the current grating on the culvert from being plugged by timber debris. The <br />grizzly would span about 50 feet and contain sediment and debris in an area between large rock <br />walls. The project would cost approximately $15,000. Removal of timber debris upstream of <br />the area could help this problem in the short term. <br /> <br />Bank Protection below West Willow Bridge <br />A small project was proposed to protect the bank that is being eroded below the concrete bridge <br />on West Willow Creek. The bank could be pulled back to a 2: 1 horizontal to vertical slope or <br />gentler, and heavy rock placed to protect the bank. The project should cost approximately <br />$8000. A timber retaining wall could also be considered. <br /> <br />Proiects with Multiole Locations <br /> <br />Timber Debris Removal <br />Locations of accumulated timber debris were noted in the study. It was proposed that the <br />Willow Creek Reclamation Committee could organize a community effort to remove timber <br />debris throughout Upper Willow Creek. Cleanup of areas other than below the Commodore <br />Mine wouldn't require much funding, but collaboration of Mineral County or other agencies with <br />a dump truck, backhoe, and/or winch would be useful. <br /> <br />Removal of timber debris below the Commodore Mine will be more difficult. However, the <br />access road into the area could be restored so that heavy equipment could enter the area. Several <br /> <br />VIII <br />