CIPP solution in Wisconsin

New Berlin, Wisconsin Uses CIPP to Repair an Aging Water Main

In 2021, the City of New Berlin, Wisconsin, encountered a question faced by many communities across the country: Continue to repair an aging water main or replace it all together?

For more than 50 years, this two-mile stretch of 16-in. diameter, ductile and cast-iron pipeline had served residences and commercial applications alike. However, the line was experiencing an increasing number of breaks each year. The decision of whether to continue to spot repair the pipes or develop long-term solutions was further impacted by an upcoming project to reconstruct the county road above the water main.

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The City needed a solution that balanced cost, impact on traffic and service outages while quickly and effectively rehabilitating the water main under Moorland Road, a concrete roadway that is the last four-lane street west of Milwaukee.

After exploring several options, such as main relocation, pipe bursting and various methods for lining, the utility chose to move forward with cured-in-place pipe (CIPP) water main lining. Michels Trenchless was hired to perform the CIPP rehabilitation services under general contractor Mid City Corp.

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CIPP solution in Wisconsin

Why CIPP?

Once only available for rehabilitating sanitary and storm sewer mains, laterals and culverts, the CIPP relining process has also been proven effective for use in pressure, force main and potable water pipes.
CIPP can be performed inside a pipe with a diameter range of 6 in. to 120 in. Liners are inserted into the pipe through a utility maintenance hole or excavated access pit. The liner is installed with air or water inversion or is pulled into place. Depending on the liner type, location and size, curing is facilitated by water, steam or ultraviolet light.

For the Moorland Road project specifically, Michels identified four advantages supporting the use of CIPP lining:

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  • 80 percent of the project’s more than 50 services were less than 2 in. in size and could be reinstated without disruptions from excavation.
  • Minimal pavement replacement due to installation lengths between access pits.
  • Minimal impact on traffic, allowing at least one lane in each direction to remain open and circumventing the need to close any four-lane cross streets.
  • Minimal service interruptions with the installation of temporary water lines and without leaving portions of the community with low pressure.

In summary, CIPP could achieve the project’s goals of fiscal responsibility by avoiding the need to rip up roads, minimal traffic interruptions and minimal impact on water service — all while practicing exceptional teamwork to ensure that the major construction to Moorland Road could proceed unhampered.

CIPP solution in Wisconsin

Water Main Work Performed

Extensive coordination is needed to determine lining access pit locations. Many of the 40 access pits for this project were placed at valves, tees and hydrant locations that would already need to be replaced by excavation. These pits must remain open for several weeks to allow for cleaning, host pipe televising and measurement, Hammerhead RS Blueline fully structural liner installation, hydrostatic pressure testing, service reinstatement, appurtenance installation and Bac-T testing.

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The majority of the 7,900-ft pipe was composed of a consistent 16-in. diameter, though the project also included 210 ft of 12-in., 170 ft of 8-in. and 250 ft of 6-in. diameter pipelines.

Strategically organized into four phases, the project encompassed 27 separate CIPP installations ranging from 110 ft to 470 ft in length. The liner was wet out each day in one of Michels’ regional facilities. The following steps were followed for each segment:

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  • Lines were cleaned using a mechanical scraping method.
  • Water service lines up to 2 in. in diameter were plugged internally using a remotely controlled robotic crawler.
  • NSF-61-certified, Class IV liners for potable water mains were installed.
  • Each line segment was hydrostatically pressure tested to 120 psi to check for water tightness and structural soundness.
  • Once tested, the plugged services were reinstalled internally with a robotic cutter.
  • Each liner termination point was finished with mechanical end seals.

Value Added

An experienced CIPP contractor, Michels is positioned to analyze, anticipate and mitigate a wide variety of issues, including unforeseen ones.

During the Moorland Road project, the crew encountered a 300-ft pipe segment with four 45-degree elbows in the 16-in. pipe while performing CCTV inspection and documentation. The elbows had not been present on the previously completed as-built drawings. Rather than requiring the general contractor to excavate and remove the elbows to line through these locations, Michels installed the liner by air inversion, a method that installed the liner through the elbows and allowed the pipe segment to be completed trenchlessly as planned.

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Michels also added value to the project by using an internal point repair system to cover existing valves and tees, which were planned to be abandoned. The new approach allowed the crew to CIPP line through these areas without compromising the structural integrity of the liner and seal off the valve or tee to the host pipe. Even better, these could be left in place, avoiding the need to dig them up and replacing them with a small spool piece of pipe.

By circumventing these potential setbacks, the project was completed on time and within the proposed three-month window.

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A recent study by Stratview Research predicts that the CIPP market will continue to rise sharply over the next four years to reach $3.8 billion in 2028. North America is projected to remain the largest market for CIPP during that span due to the average age of current potable and sewage water structures.

Municipalities’ increased spending on utilities and pipeline rehabilitation will drive up the adoption rate of high-performance CIPP options.

Michels’ recent undertaking in New Berlin is among the largest water main lining projects in Wisconsin to date and is expected to extend the life of this pipeline by 50 years or more. Given the ongoing need for cost-effective, minimally invasive solutions for old water mains, it is possible even bigger, more complex projects will follow.

Gaven Kobes is project manager-water lining operations at Michels Trenchless Inc., part of the Michels family of companies.

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