FLOOD01787 - Laserfiche WebLink

Home Browse Search

'. . . . . . . . . . . . . . . . . . . Creek Ditch No.2, and flow under South Boulder Road to South Boulder Creek. Greater South Boulder Creek spillage would overtop the Viele system and flow onto the freeway. Some portion of this spillage and local drainage flows can be conveyed by the Anderson Ditch to the east to South Boulder Creek, subject to some spillage to the north at several points, the first and most significant of which would occur near the Anderson culvert under the Highway 36 eastbound off ramp. 3. West Vallev Overflow. Greater South Boulder Creek spillage (than 700 to 1000 cfs) would flow onto Highway 36 and pass by the Anderson Ditch, and then largely overflow the Highway 36 barrier and discharge to the north of the freeway on the west side of Foothills Parkway and travel north, along the west side of Foothills Parkway. At the intersections of Foothills and Baseline flow is first retarded by two small storage ponds. Flows such as the 100 year flood can follow anyone of seven routes. Three potentially leave the watershed along Foothills Parkway to the northwest, two flow east on the lanes of Baseline and split again to the north through the Country Club Park neighborhood, and either by culverts under Foothills or over the roadway to the east storage. The east storage first discharges by a box culvert which has been partially obstructed by an earth dike to form a "poor man's" hydraulic control. The culvert under Baseline directs flow to the Crossover Ditch, on the north side of Baseline, which then carries flow easterly to Dry Creek Ditch No.2 near 55th. However the east storage spills at moderate flows to Baseline, which then can contribute to and join spillage from the Crossover Ditch, and add to the spillage through the Country Club Park subdivision. Reference documents refer to drainage problems in these areas. These spillages eventually go to the Wellman Ditch adding to runoff already being carried from Bear Creek and probably from the three South Boulder Creek spillages following Foothills. At 55th and the Wellman Ditch, Dry Creek No.2 and the Crossover Ditch flows join the Wellman Ditch except for minor flows conveyed in the Dry Creek Ditch No.2 undercrossing pipe. The Wellman Ditch acts as a major collector channel, but can spill flow north through the golf course and probably at higher flows through the Centennial Trails and Arapahoe Ridge subdivision west of 55th. 11- 4