Mortenson was selected as the General Contractor for the construction of a new storm water detention facility for flood prevention and sedimentation control. It is an approximately 27-foot-tall earthen embankment with 4:1 side slopes and will provide approximately 170 acre-feet of storage volume below the crest of its emergency spillway. The 365-linear-feet wide spillway and downstream face will be armored with roller-compacted concrete.
A portion of the existing grouted boulder-lined channel at the upstream end of the facility will be realigned, and a grouted boulder drop structure will be constructed to convey the Camp Creek flow. A small storm sewer system will be constructed to control local drainage. An 8-feet-wide by 6-feet-high, cast-in-place, reinforced concrete box culvert will be constructed as the outlet conduit. Approximately 944-linear-feet of Colorado Springs Utilities will be maintained, and an 8-inch sanitary sewer main will be relocated, primarily through trenchless construction.
Public trails will be reconstructed through the project site, including a paved extension of the Foothills Trail within the 31st Street channel section and potential bridge improvements. This will also include the extension of the underground portion of Camp Creek from Bijou Street/Echo Lane to West Platte Avenue.
Major quantities include:
- Earthwork (185,000 CY)
- RCP (450 LF)
- Grouted boulders (2900 SY)
- Riprap (1500 CY)