Due to heavy snowmelt as well as an unusual amount of heavy thunderstorms and flash flooding in the spring of 2015, the City of Colorado Springs, Colorado experienced significantly compromised storm drainage infrastructure. Numerous channels and hillsides were experiencing erosion, head cutting, and a loss of structural stability.
In the North Rockrimmon Channel area, this erosion was impacting the stability of the nearby residential development. Many homes were dangerously close to being lost, due to the expanding footprint of the channel. Given the seriousness of the situation and the limited availability of time, the city decided that the best long term approach would be to fully enclose the channel with a large, 96” DuroMaxx® steel reinforced polyethylene (SRPE) pipe. The City also planned to utilize 50,000 tons of sediment from Waldo Canyon burn scar – repurposing this decomposed granite as backfill around the 96” DuroMaxx SRPE drainage pipe would not only provide suitable support but save the City substantial dollars ultimately providing a solution that was designed to withstand a 100-year storm.
The City was familiar with DuroMaxx SRPE after having used it to repair another sinkhole project near Austin Bluffs Parkway. They needed a pipe solution that not only could handle high velocities with ease but also have superior joints and hydraulic performance. DuroMaxx provided an ideal solution with 80 ksi steel reinforcing ribs providing the necessary structural support and a hydraulically efficient profile capable of Manning's "n" values of 0.011 to 0.013.
To maximize construction time, the contractor (Wildcat Construction) was able to backfill the DuroMaxx SRPE system while the 30 psi welded coupler (WC) joints were sealed from the inside of the pipe. This project faced many heavy storms while in construction, and the pipe was able to handle and carry the flow through without being compromised. All those involved in this project from the City of Colorado Springs to the nearby residents impacted by these recent developments have been extremely satisfied with the finished product.