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<br /> <br />The following are the major public and environmental issues: <br />Accelerated streambank erosion and lowering of the water table have <br />resulted in a loss of, or impacts to, aquatic and riparian habitat and <br />organisms. <br />Affects on the aesthetic values of the area. <br />Increased sediment delivery downstream is currently impacting habitat and <br />water quality in the lower reaches. <br />Recreational fishery ie being impacted due to loss of habitat, <br />sedimentation and erosion. <br />The stream has lost its "sediment transport capabilities° through the <br />braided portions of the channel. <br />V. Alternatives <br />Three alternatives (including the alternative of taking no action) were studied <br />in detail and are presented here for consideration in the decision process for <br />this proposed project. The two action alternatives include mitigation <br />measures, monitoring measures, and are in conformance with the Forest <br />Management Standards and Guidelines. (The Forest Management Standards and <br />Guidelines ere published in the Forest Plan on pages III-173 thru III-188.). <br />The alternatives include: <br />Alternative 1. NO ACTION ALTERNATIVE. <br />This alternative would leave the aquatic/riparian system and <br />floodpleins as they are and no plans to stabilize the river system <br />would be implemented. <br />Alternative 2. RESTORE AQUATIC/RIPARIAN SYSTEM TO A STABLE CONDITION. <br />MAINSTEM RECONSTRUCTED TO A "B" CHANNEL TYPE. (Preferred alternative) <br />This alternative would consist of using the existing mainstem channel, <br />above the confluence, and creating a step-pool ^B" channel type where <br />the channel now exists. The gradient of this channel would be 4.2i <br />with rock vortex weirs spaced approximately every 130 feet. This <br />single channel would be designed and constructed in a manner which <br />would replicate the type of channels that are associated with alluvial <br />fans. <br />The South Fork above the confluence and the mainstem below the <br />confluence would be realigned. Revetment, rock vortex weirs and <br />rip-rap would be used to reestablish the banks, provide instream <br />structure and return the system back to a stable situation. This <br />would be accomplished using design criteria based upon sediment load, <br />discharge and valley gradient. The attached plan shows restoration <br />design associated with this alternative. <br />4 <br />