Project Overview
In late 2017, Insituform was contracted by Colorado Springs Utilities to rehabilitate 300 feet of 16-inch steel pipeline running along Nichols Reservoir, near Pike’s Peak. The pipeline formed part of infrastructure that would soon be surrounded by new construction at the dam, making future access extremely difficult.
The steel pipeline also included two 45-degree bends and required a 25 psi pressure rating, meaning a specialised pressure-capable lining system was essential.
Project Challenges
The rehabilitation presented several unique challenges:
- The site was located within Pike National Forest, limiting access and staging areas
- The project sat at an elevation of 8,700 feet, creating environmental and logistical constraints
- Most dam-related pipelines do not typically require pressure-rated solutions, making this application more specialised
- Future access to the pipeline would be severely restricted due to upcoming structural additions
Given these factors, the solution needed to provide structural integrity, pressure capacity, and reliable long-term performance with a minimal jobsite footprint.
The Solution: InsituMain® Fibre-Reinforced CIPP
The client and AECOM selected the InsituMain® fibre-reinforced cured-in-place pipe (CIPP) system to meet the project requirements. This pressure-rated CIPP technology provided:
- A structural solution capable of withstanding the 25 psi design pressure
- The ability to navigate multiple 45-degree bends
- A trenchless installation method with excellent accessibility for constrained dam environments
- A small jobsite footprint suitable for sensitive natural areas
Material Composition
The InsituMain® liner used for this project consisted of:
- Traditional felt material
- Added glass reinforcement to provide both internal and external load capacity
This composite structure ensured the pipeline could withstand operational pressures while restoring structural integrity.
Installation and Results
Installation was completed in two shots, where alternative technologies would have required three, reducing onsite time and minimising disruption.
The project was delivered as part of a hard-bid contract, with SEMA serving as the general contractor. SEMA self-performed all supporting work, including pit construction and site preparation for the CIPP installation.
Following installation:
- The rehabilitated pipeline was pressure tested to 40 psi
- The system successfully passed testing
- The pipeline was returned to service, meeting all performance requirements
The project demonstrates the suitability of InsituMain® CIPP for pressure-rated dam infrastructure, particularly where access, elevation and alignment complexity limit traditional rehabilitation methods.
