2016-04-04_REVISION - M1993035 - Laserfiche WebLink

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throughout the development of this Plan, it was determined that the Tiger Road barrier should be removed and this section of the Swan River allow for upstream and downstream fish passage.Therefore the existing culverts through Tiger Road will be replaced with a free-span arch. The proposed channel has be re-aligned so that flows will not need to cross Muggins Gulch Road, eliminating this second crossing and barrier altogether. The restoration reclamation plan also incorporates two types of aquatic micro-habitats; (I) boulder clusters and (2) log spurs (large woody debris). These features will be placed in pool and/or glide sections where velocities are low and water is slightly deeper and are intended for habitat cover only and not intended for bank stability or grade control. Riparian Restoration The restoration reclamation plan has developed a riparian corridor that is more than two times the stream bankfull width, inclusive of the channel itself.This width provides a flood prone area that is consistent with the intended channel type. Evaluation of aerial photographs, literature review and professional judgment of regional wetland/riparian habitats indicated that prior to significant land disturbance (i.e., dredge operations), the Swan River Resource likely contained suitable elevation, geomorphic setting and climate for montane willow riparian shrubland. These riparian systems, which are found throughout the region, are located along streams and drainages and typically occur as mosaic of vegetative communities. These systems consist of temporarily, seasonally and intermittently flooded shrublands comprised of broad-leaved deciduous willow dominated species in the midstory canopy and an understory of herbaceous species including a mix of grasses, forbs, sedges and rushes. These corridors are some of the most biologically diverse habitats having a consistent source of water and providing structural habitat diversity utilized by a wide variety of wildlife. This restoration reclamation plan focuses first on establishing a deeply rooted and dense groundcover dominated by native riparian herbaceous species that are typical to the region. The intent is to quickly establish a groundcover to stabilize soil, minimize establishment of invasive species and promote long-term successional development. To facilitate complete ground coverage and seed bank development within the reclamation area, the entire riparian zone will be seeded with the specialized Riparian Seed Mix with locally native species that germinate rapidly and provide complete groundcover tolerant of a wide variety of hydrologic conditions. Second, strategically placed riparian shrub plantings will occur primarily along outside bends of the new channel to provide not only bank stability but also increased biomass and structural habitat for the fishery and terrestrial wildlife. Additionally, the shrub plantings are intended to provide increased biomass to the stream (leaf-litter), overhead cover (shading) and increases bug life (terrestrial and aquatic, such as caddis). The riparian habitat is designed to interact with local groundwater (within I' to 2' of the surface) as well as seasonal overbank flooding.The channel has been designed so that the riparian fringe above the bankfull is situated between I.I' to 3' above the bottom of the channel and lowest groundwater elevation. This provides near surface moist to the riparian fringe from groundwater and stream flows through much of the growing season. The riparian zone is anticipated to develop wetland characteristics however has not specifically designated as wetland creation. Upland Restoration The Plan depicts upwards of 13-acres of upland area that will be reclaimed. Reclamation will include contouring existing dredge pile and project excavation spoils. These areas will be graded to varying and undulating natural landforms based on material quantities. The upland areas will be capped with three inches of unconsolidated soil