Details of Objective 1: To help restore channel dimensions and reduce dewatering of the unconfined aquifer, install grade stabilization structures. A) If gabion-weirs are used these diagrams illustrate how they will be constructed. The fill material will consist of cobble rock 5-10" in diameter to for uninhibited flow through the gabion-weir structures, but will be consolidated enough to accumulate course sediment and raise the channel profile. B) The approximate dimensions of these structures, whether gabion or other forms of rock weirs, will be 4.5 feet high from stream-bed surface, embedded 1-2 feet subsurface, embedded 5-10 feet in banks. The stream channel dimensions are variable, but range from 10-20 feet deep and 10-30 feet wide. In some stream sections, heavy machinery can be positioned on the road to complete this work, but other section will require heavy machinery in the channel. Details of Objective 2: To reduce bank erosion and associated lateral incision, install bank protection structures. These structures may consist of gabion baskets and/or logs androcks to reduce/eliminate bank erosion, and along County/NFS Road, road from lateral incision A) If gabion baskets are used, they will be filled with cobble rock 5-10" in diameter. Other structures are acceptable if agreed upon by USFS Hydrologist and RRR representative. B) To increase bank stability and to reestablish riparian vegetation along the banks. If gabions are used,put layers of soil and willow plantings in the lower tiered gabion baskets. C) All of the heavy machinery work should be able to be conducted from the road as there are only a few locations along the road that need this work. If work must be done from in the channel, USFS hydrologist will be consulted and provide approval first.
