Mirage Channel Reconstruction
Current Status: Design was completed in late June 2013 along with securing easements from the Preserve at Briargate, School District 20 and City Parks Department. Bids were opened June 20, 2013 and a construction contract was awarded to Tezak Heavy Equipment. Construction started July 29, 2013 with an anticipated completion date of December 17, 2013.
Background: The project area consists of a reach of the South Pine Creek concrete lined channel from Union Boulevard to the outfall into a pond approximately 1500 feet to the west. The project west of N Union Blv. between Rampart High School and the Preserve at Briargate housing development. This channel segment was constructed in 1982. Portions of this channel failed in 2010. In response, emergency City funding and workers were used to repair the damaged section. On July 8, 2012 another segment of the channel failed from a reported two inch rain storm of unknown duration. City officials were contacted and responded by providing temporary stabilization measures in the form of rip rap (grouted and loose). It was then decided that total reconstruction of the subject segment was needed due to the proximity of the adjacent development, historic failures, and the City’s desire to upgrade the reach to current design criteria and standards.
Wilson and Company was selected and awarded a design contract to analyze the channel in December 2012. Part of the analysis consisted of examining the feasibility of using different channel types and alignments such as full pipe enclosure, natural meandering streambed and pipe /channel combinations. The design process took input from the Preserve at Briargate HOA, Rampart High School and School District 20 officials as well the City Parks, Recreation & Cultural Services Department. The preferred option resulted in a shotcrete lined channel twice as large as the original, relocated to the north approximately 25 feet to increase separation from the housing development and a 15” sanitary sewer trunk main.
Mike Chaves (Project Manager, 385-5408)