About Progressive Pipeline Management (PPM)

Progressive Pipeline Management (PPM) is a national leader in trenchless gas pipeline rehabilitation, facilities maintenance, and environmental emergency response. Founded in 2002, PPM employs more than 125 people and has installed over 1.5 million linear feet of Cured-In-Place Lining (CIPL) across 22 states—restoring aging gas infrastructure safely, efficiently, and with minimal surface disruption.

What Is Cured-In-Place Lining (CIPL)?

Cured-In-Place Lining (CIPL) is a trenchless rehabilitation technology designed specifically for natural gas distribution and low pressure transmission pipelines. It rehabilitates leak-prone or corrosion-compromised metallic pipe by installing and curing a bonded composite liner inside the host pipe. The result is a new composite pipeline, elimination of and the structural rehabilitation of the host pipe—extending its useful life by more than 100 years while significantly reducing excavation, avoiding total replacement, and drastic reduction of large-scale restoration. CIPL is effective in diameters from 2 to 48 inches and is applicable to cast iron, bare steel, wrapped steel, and wrought-iron mains. It maintains flow capacity, the existing maximum allowable operating pressure (MAOP) and can safely withstand pressures up to 450 psig.

CIPL is most effective in metropolitan areas or where excavation is costly, complex, or impractical, including:

• Bridge, river, railroad, and highway crossings

• Dense urban and downtown corridors

• High-restoration-cost areas (curb-to-curb paving or historic streetscapes)

• Pipelines adjacent to critical infrastructure such as schools, hospitals, and transit systems

• Large-diameter mains where maintaining throughput is critical

With recent advancements in temporary gas-supply and accelerated curing technologies, smaller-diameter mains (2–12 inches) are now equally well-suited to lining, especially in areas where speed, minimal disruption, and restoration avoidance are priorities.

CIPL Pressure Integrity Test – A CIPL rehabilitated pipe is a safer pipe.

Building on the 2017 NYSEARCH and Cornell longevity testing, the following demonstration shows how lining cast-iron pipe changes the failure mode and enables the pipe to maintain pressure integrity under conditions that would typically result in complete host pipe failure. It also confirms sustained pressure integrity in both cast-iron and steel specimens at 20x and 40x the original design pressure for 24 hours, respectively.”

Explore the CIPL Frequently Asked Questions (FAQ)

The following FAQ addresses the most common technical, regulatory, and operational questions about CIPL—from installation, curing, and service reinstatement to PHMSA compliance, OQ standards, and long-term structural performance.

Q: Can lining (CIPL) rehabilitate both cast-iron and steel pipes?
A: CIPL rehabilitation can be performed on all metallic pipes, including cast iron, steel (wrapped or bare), and wrought iron. Lining does not, however, eliminate the need for cathodic protection.

Q: What happens to the exposed liner when all the bare steel corrodes away?
A: Corrosion occurs within localized “corrosion cells,” which eat away at a small area of pipe until a hole forms—typically around ¼-inch in diameter. Such holes cause a gas leak and are quickly repaired. The pipe does not thin uniformly until it disappears. The exposed liner can support earth and traffic loads over corrosion holes up to 3 inches in diameter. If a steel pipe installed in the 1930s has developed only a ¼-inch hole in nearly 100 years, it would take far longer than the liner’s lifespan for that to grow to 3 inches.

Q: What is the life expectancy of the liner?
A: Extensive testing conducted by Cornell University and NYSEARCH has demonstrated an expected service life exceeding 100 years. Axial, rotational, expansion, and contraction testing—totaling over two million cycles—was performed under the supervision of major utilities including National Grid, Con Edison, and PSEG.

Starline® CIPL has undergone more than $15 million in independent testing across multiple facilities. These results confirm that the bonded liner maintains its structural and pressure integrity over a century-long design horizon. Full testing data and reports are available upon request.

Q: How much does it cost to line a natural gas main, including all PPM costs for materials and installation?
A: The table below provides 2025 per-foot pricing estimates for lined pipe by diameter. Actual costs may vary based on factors such as tariffs, transportation fluctuations, job location, project length, order volume, and site-specific requirements (e.g., work windows and traffic control stipulations).

This pricing reflects PPM’s total estimated price for Starline® CIPL materials (manufactured in Germany) and installation. PPM collaborates with each client to optimize project design and achieve the lowest possible delivered price once all project details are known.

Q: What pipe diameters and pressures can lining accommodate?
A: Lining can be installed in metallic pipes from 2 to 48 inches in diameter. Starline® CIPL has been tested to withstand pressures up to a maximum allowable operating pressure (MAOP) of 450 psig.

Q: Can a lined segment of pipe be cut in the future?
A: Yes, using a toothed cutting blade such as a high-speed reciprocating saw. Snap-cutting will not work because the liner resists the fracture, and a punch-out method may jeopardize the liner bond prematurely. All cuts in steel or cast-iron pipe must use a toothed blade.

Q: How independent is the liner from the host pipe’s condition?
A: Tests by Cornell University with funding from PHMSA several utility companies confirm that CIPL retains full pressure integrity even after major host-pipe degradation. Lined segments withstand corrosion holes up to 6 inches and circumferential gaps up to 3 inches without failure. The bonded structure forms a Class II composite pipeline—a unified pressure vessel of liner + host pipe.

Q: What are typical customer outage durations?
A: Ambient-cure installations generally require 24 hours from isolation to service reinstatement.
Accelerated curing with UV, forced hot air or hot-water activation reduces total lining operation to 8–12 hours.

Q: How does CIPL support methane emission and environmental compliance?
A: CIPL seals all joints, leaks, and porosity, eliminating gas migration and methane emissions. Its trenchless nature reduces surface excavation, traffic impacts, and restoration emissions. The technology aligns with PHMSA and EPA methane-reduction goals and qualifies for inclusion in leak-prone-pipe or emission-mitigation programs.

Q: How do CIPL costs compare with traditional replacement?
A: CIPL typically saves 30–60 percent overall in urban, high-restoration, or access-limited areas by avoiding paving, traffic control, and restoration expenses. Its leak-elimination and prevention benefits further reduces long-term methane-loss costs and prevent leaks in the event of host pipe failure.

Q: Can utilities capitalize CIPL rehabilitation projects?
A: Yes. Many utilities classify CIPL as a capital improvement under infrastructure-renewal or leak-prone-pipe programs. Capitalization eligibility follows each operator’s accounting policy and DPU precedent.

Q: How do CIPL-lined pipes perform in the event of third-party damage or soil movement?
A: Unlike rigid host materials such as cast iron or steel, CIPL creates a flexible composite pipe with a more favorable failure mechanism under stress. Extensive CIPL Pressure Integrity testing has demonstrated that the bonded liner can maintain pressure containment even after the host pipe has failed due to circumferential breaks, longitudinal cracks, or complete section loss.

In scenarios such as a backhoe strike, undermining soil from a water main break, or other third-party impacts, the liner remains intact and pressurized, acting as a composite pressure vessel rather than a brittle structure. The liner is engineered to absorb and redistribute strain by intentionally dis-bonding at controlled levels, a behavior governed by the specific resin bond strength requirements in ASTM F2207. This controlled dis-bonding allows the liner to flex and relieve stress without losing pressure containment.

This resilience represents a key safety advantage of CIPL over traditional rigid materials, ensuring system integrity even under severe, unplanned external loading or ground movement.

Access the full length CIPL Testing Video

NYSEARCH & Cornell University – 2017 Longevity testing for CIPL

The NYSEARCH and Cornell University testing program evaluated CIPL-lined pipes that had already been in service for 10–16 years. These lined, field-aged pipes were then subjected to accelerated mechanical and thermal aging to simulate 100 years of service. The pipes maintained pressure integrity with no leakage, showed minimal loss of tensile, hoop, and bond strength, and only localized debonding at weaker joints. The results indicate that properly installed CIPL systems can provide up to 100 years of reliable service life extension.