Our crews are currently rehabilitating a water main that runs beneath the river by installing a carbon fiber lining inside the pipe. Carbon‑fiber water main lining is used because it provides a fast, strong, and minimally disruptive way to rehabilitate aging or damaged pipes, especially large‑diameter 48" transmission mains, like the one we’re working on for this project.
This upgrade is essential to maintain long‑term reliability.
Project Schedule & Work Hours:
| Status | In Progress |
| Start Date | 9/1/2025 |
| End Date | Mid Summer 2026 |
Work Hours: Equipment must stay operational overnight due to the need to keep the pipe dewatered.
About the Work:
To perform the work safely, crews must enter the pipe, which runs along the river bottom at 26th street over to the north shore. To access this large, underwater pipe, we must dewater it. Our equipment located near the building is necessary to the operation and must continuously run to maintain a safe and functional work environment
We understand the equipment creates noise, and this is difficult, especially during overnight hours. Our teams are doing what they can to reduce noise in the evenings wherever possible. Construction is expected to continue through mid‑summer.
Additional Details about why this work is necessary:
Q: Why are we doing carbon fiber lining?
A: This work restores structural strength without full replacement. Carbon fiber composites are extremely strong and lightweight. When applied inside a pipe, they essentially create a new structural “pipe within a pipe.” This allows an old water main to regain or exceed its original pressure rating. An interesting fact is that this pipe was originally installed in 1914, so it is quite old!
Carbon fiber relining also minimizes excavation and community disruption. Instead of digging up long sections of roadway, crews access the pipe through small pits or existing manholes. This means:
- less traffic disruption
- shorter construction timelines
- less noise and street restoration work
- lower impact on residents and businesses
This is a huge benefit in dense urban areas like Pittsburgh.
Carbon fiber lining extends service life 50+ years
Carbon‑fiber reinforced polymer (CFRP) systems are corrosion‑resistant and highly durable. Once installed, they slow deterioration and give utilities a long-term solution without the cost and complexity of full pipe replacement.