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: Materials to create confining terraces and floodplains would be <br />obtained through either the excavation of material onsite, resulting <br />in the creation of ponds, or import of material from off site <br />locations. <br />Alternative 3. RESTORE AQUATIC/RIPARIAN SYSTEM TO A STABLE CONDITION. <br />MAINSTEM RECONSTRUCTED TO A "C" CHANNEL TYPE. <br />This alternative would involve reconstructing the mainstem channel, <br />above the confluence, to a meandering "C" channel type across the <br />existing alluvial fan. In the mainstem San Miguel River, above the <br />confluence, a new channel would be created consisting of an upper and <br />lower meander, the length of which would reduce the gradient of the <br />new channel to 3.7Z. The lower meander would require the construction <br />of approximately 660 feet of new channel through a fluvial terrace <br />linking it to the existing channel. Anew confluence of the two <br />rivers would be created. In order to reduce the risk of losing the new <br />channel during high runoff, a hard point spillway will be installed <br />using gabion/rock structures where the new channel takes off from the <br />existing channel. This is intended to prevent any downcutting and <br />thus result in the abandonment of the new channel. Under this <br />alternative, the existing channel would be abandoned and a new channel <br />constructed as shown in the attached plan for this alternative. <br />The South Fork, and the mainstem below the confluence, would be <br />redesigned in a manner as described under Alternative 2. Materials to <br />create confining terraces and floodplains would be obtained through <br />either the excavation of material onsite, resulting in the creation of <br />ponds, or importing material from offsite locations. <br />One action alternative (as opposed to the No Action Alternative) was <br />investigated, but eliminated from further consideration at various stages of <br />the environmental analysis. That alternatives is described here. The central <br />reason for eliminating this alternative, as being infeasible or impractical, <br />are explained. <br />Alternative considered, but not analyzed: <br />1) RESTORE ONLY THE SOUTH FORK SAN MIGUEL AND THE MAINSTEM BELOW THE <br />CONFLUENCE. <br />This alternative would leave the mainstem, above the confluence, in <br />its present condition and would significantly impact any restoration <br />work that was planned for the South Fork and the mainstem below the <br />confluence. It would not be practical to restore a part of the river <br />system and not consider the influence, the unrestored parts of the <br />river, would have on the rest of the system. <br />S <br />