The Project would replace approximately 448 linear feet of the existing wooden flume, which is highly susceptible to damage from wildfire and other natural hazards, and replace it with a more durable ignition resistant concrete conveyance structure (i.e., cast-in-place or precast concrete flume). The Project would also require the rock wall foundation be either stabilized in place or replaced with a mechanically-stabilized earthen (MSE) wall. The Project would begin with mobilization, access, and site preparation, which involves construction of temporary access roads to provide all-weather access for equipment to the site, demolition and disposal of the existing wooden flume, and clearing and grubbing of vegetation within the limits of work area. Next, the rock wall foundation would be either stabilized in place or removed and replaced with an MSE wall. To stabilize in place, the rock wall foundation would be reinforced with a shotcrete facing that is placed over the exposed face of the rock wall, followed by installation of rock anchors and grouting. Replacement of the rock wall foundation with an MSE wall would involve demolition of the existing rock wall, excavation to competent foundation material, installation of MSE retaining structures, placement of compacted backfill, installation of appropriate drains, and installation of rock anchors to stabilize sections of the embankment and foundation
