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Willow Creek Reclamation Committee <br />Windy Gulch Project Final Report <br />PROJECT DESCRIPTION <br />The following section describes the phases of the project followed by photos. The county <br />preferred project construction in late fall due to heavy tourist traffic on the Bachelor Loop road <br />during summer. Culvert excavation and placement commenced in October ?005. <br />Due to the wall thiclaless of the precast concrete sections, the trench had to be excavated about <br />1.5 feet lower than the level of the old culvert. Significant care was taken to locate utilities <br />during excavation. A small sewer line was found just below the level of the trench, but is <br />protected by an outer iron pipe. A water line lies only 2 to 3 feet below the trench level. <br />Signficant water was traveling from upstream within the pipe bedding, and some of this water <br />now exits under the new culverts. Tlus water probably kept the line from freezing under the old <br />culvert and should hopefully keep the line from freezing under the new culvert. The water was <br />tested and had some chlorine residual but also had high levels of zinc (as does Willow Creek). <br />The chlorine indicates that some water may be coming from an upstream water leak probably <br />near the community center connection. However, the high zinc suggests that much of the water <br />may be coming from Willow Creek or a ground water source (although the pipe bedding may be <br />high in zinc) and the upstream leak may small If the leak is large and is fixed, the water line <br />may then have more tendency to freeze. A preliminary design and cost estimate were made to <br />relocate the water line around the culvert. However, the City opted to manage potential <br />replacement of the water line and will responsible for the line in the fut<ire. <br />The precast culvert sections were placed using a large 75-ton crane. A small amount of bedrock <br />had to be removed, but the upstream end of the culvert fit nearly perfectly beside the bedrock. A <br />bedding of roadbase and gravel was placed udder the culverts, but there is a potential that water <br />under the culverts may cause some shifting due to freezing. <br />Headwalls, wingwalls, and footers were designed using CDOT specifications. The WCRC <br />director worked directly with the assistance of a local contractor to place rebar, build forms, and <br />pour concrete. Forms were insulated to protect from cold temperatures. The headwalls and <br />wingwalls were poured with tinted cement in an effort to enhance aesthetic appeal within the <br />surrounding natural setting. Some of the insulation stuck to the concrete. Therefore, a colorized <br />mortar coating was applied to the headwalls and wingwalls. <br />Several rock weirs were placed by hand upstream of the culvert to stabilize the new channel that <br />was cleared. Rock was also placed by hand just downstream of the culvert to control erosion. <br />Ali excavator was used to reshape the downstream chamlel, and two large weirs were placed <br />using aft diameter rocks. These weirs should control down-cutting of the exit chamlel and <br />prevent undercutting of the culverts during large floods. A pilot chamlel was formed through the <br />downstream chamlel and weirs to convey the typical low flows of Windy Gulch. Banks were <br />reseeded and willow stakes were placed on outside bends. Finally, an asphalt "cold" patch was <br />placed on the roadway. <br />An excavator with a blade was used to place material in the low section of the levee. A thin <br />layer of roadbase was also placed on top of the material. <br />