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Summary of Proposed.Channel Characteristics <br /> Channel Length 5,131 feet <br /> Channel Slope 1.27% (Avg.) <br /> Bankfull Flow 103 cfs <br /> Ave Bankfull Width* 21 feet <br /> Ave Bankfull depth* I.I feet <br /> Ave Pool Bankfull depth 3 feet <br /> Pool Spacing 227 feet(9 x bankfull width) <br /> Width/Depth Ratio* 19 <br /> Entrenchment Ratio* >2.9 <br /> Sinuosity 1.7 <br /> *measured at riffle beginning <br /> Groundwater Intercept <br /> As part of the restoration reclamation assessment piezometers were installed throughout the Swan River Valley <br /> in order to understand the location and seasonal variation of the local groundwater table.The restored channel <br /> was designed so that the stream thalweg was at, or lower than the current groundwater level. This was done to <br /> create a stream that would generally be gaining along its length. Having the stream at or below the existing <br /> groundwater level has the added benefit of near surface water to support the riparian vegetation along the <br /> length of the stream. Up to three years of data was available from some of the piezometers. Review of the <br /> piezometer data indicated that there was not significant changes in groundwater levels from year-to-year or <br /> from season-to-season. Despite this apparent low fluctuation, the design of the stream channel includes a low <br /> permeability layer below the active channel.This low permeability layer will help ensure that water remains at <br /> the surface in the event groundwater levels drop below anticipated elevations. <br /> Low Permeability Layer <br /> A low permeability layer will be utilized below the new channel and extend outward across the riparian zone. <br /> The intent of the layer is to minimize channel surface flow infiltration into the underlying cobble substrate while <br /> maintaining groundwater flow into the channel. The liner is also designed to allow groundwater inflow into the <br /> channel. The layer will consist of a mixture of onsite screened or processed native materials (fines and gravels), <br /> placed I foot thick and compacted.The maximum stone size will be 4 inches and there will be at least 25%fines <br /> content (percent passing the US Number 200 sieve). <br /> Aquatic Habitat Restoration <br /> The restoration reclamation plan focuses on creating a healthy, diverse and self-sustaining aquatic environment <br /> which includes specific habitat requirements for native cutthroat trout.While native cutthroat trout are not the <br /> dominant species present, this species serves as the target species providing the basic habitat requirements for <br /> all regional trout species. <br /> One of the initial objectives of this restoration reclamation plan is to eliminate the existing fish barrier at Tiger <br /> Run and Muggins Gulch Road.Through discussions with the Forest Service, CPW and project proponents <br />