Insituform Technologies, Inc. has contracted with Colorado Springs Utilities to provide sewer rehabilitation and replacement over the next three years. The budget for the contract is $16.8 million.
The work is a phase of the utility’s 10-to-15-year aggressive wastewater infrastructure inspection and assessment program, Sanitary Sewer Evaluation and Rehabilitation Project (SSERP). The utility covers a 200 square mile area of Colorado Springs and has 1,450 miles of pipe, with 30 to 35 miles of new pipe added each year.
“Having successfully completed rehab work for Colorado Springs Utilities in the past, Insituform was eager to win this contract,” says Joe Lane, business development manager of Insituform. “With our capabilities for management of large-scale projects, we believe Insituform is a good fit for the utility’s needs.”
Initial plans call for work on sewer pipe in eight basins in the Colorado Springs Utilities system: Bear Creek, Downtown, Garden of the Gods, Lower Sand Creek, Patty Jewett, Rockrimmon, Shooks Run and Spring Creek. In April, the company began notifying residents and businesses in surrounding areas about the planned work and determining logistical methods to minimize the impact on each area.
As deteriorating pipe in the system is identified via the assessment program, Insituform will rehabilitate it, or dig it up and replace it if it is beyond rehabilitation. Lane said a large percentage of the pipe is expected to be rehabilitated with the cured-in-place (CIPP) process, the most widely used trenchless (non-dig) method for restoring structural integrity to and removing infiltration from sewers.
Working from manholes, Insituform will be installing a flexible liner inside these existing sewers. Once in place, the liner is then heated and cured into a structurally sound pipe-within-a-pipe. A typical installation takes about a day to complete, compared to the weeks it can take to dig up and replace pipe.
Some Colorado Springs Utilities pipe not suitable for cured-in-place rehabilitation and may be rehabilitated using pipe-bursting methods, in which a new polyethylene pipe is pulled into an existing sewer pipe through a manhole. The new pipe has a head that bursts the existing pipe and pushes it into surrounding soil. The new pipeline fills the cleared space.