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1.0 Project Background <br />The Upper Slci Creels Watershed Erosion Control and Restoration Project addressed <br />severe sedimentation and erosion impacts to the upper Slci Creels Watershed caused by <br />stormwater runoff from the Pikes Peak Highway, located on Pikes Peak just west of the <br />city of Colorado Springs, CO. Slci Creek is one of the most degraded waters within the <br />Pikes Peak Watershed. A 1993 Forest Service study concluded that the creek was out of <br />equilibrium and was carrying an extremely high sediment load. Observed suspended <br />sediment in the creek significantly exceeded the sediment threshold 100% of the time <br />with the average exceedance calculated at 27,000%. According to a 2004 water quality <br />report, sediment in the creek has severely stressed the creek's aquatic life. The high <br />sediment loads carried by Ski Creek have also been found to be negatively impacting <br />storage capacity of the South Catamount Reservoir, a primary source of drii~lcing water <br />for the City of Colorado Springs. <br />Paving operations and sediment controls were completed on the Pikes Peak Highway in <br />this area in 2006; however stormwater runoff from 1/2 mile of highway and drainage <br />from 23 acres is still being conveyed into the upper Slci Creek channel with an estimated <br />flow of 35cfs fora 2yr storm event. The upper watershed is so degraded that the Forest <br />Service's 1993 report concluded that a discharge of only 20cfs within Sld Creek is <br />estimated to carry a sediment bedload of 2094 toi~/acre, an amount which would severely <br />impact aquatic habitat. <br />The project reach of upper Slci Creek was divided into three distinct sub-reaches (Figure <br />1). The downstream most sub-reach consists of a lower gradient deposition area <br />immediately behind the Glen Cove li1n. This segment is characterized by an over-wide <br />channel subject to frequent deposition of materials eroded from the channel upstream. <br />This segment is highly unstable, and exhibits frequent lateral migration, down-cutting, <br />and re-aggradation of sediment entrained in the channel upstream. This segment also <br />sees considerable human traffic, due to the proximity of the lodge and the highway, and <br />suffers from sparse vegetative cover along the very unstable stream bai~lcs. The primary <br />goal of the project throughout this segment was to create vertical and lateral stability <br /> <br />