California State University, Los Angeles, made the decision to not let a leaking, underground HVAC pipe slow down campus activity. A traditional re-pipe would have caused destruction that would prohibit use of a popular service road. Use of a no-dig technology provided a cost-effective solution that did not require demolition or disruption to the campus grounds.

Project: Rehabilitate an aging HVAC pipe system to stop leaks without destroying or disrupting the campus' surrounding hardscape and landscape.

Customer: California State University, Los Angeles, a public university with more than 20,000 students and more than 1,000 faculty members. The campus consists of 175 acres in eastern Los Angeles.

Site: The university’s Fine Arts building, central plant, and the area between them where the HVAC system’s pipes run underground.

System: The supply and return lines for the three-story Fine Arts building’s HVAC system. The 5- and 6-inch steel pipes run approximately 15 feet beneath the ground between the Fine Arts building and the university’s central plant. The pipes are more than 50 years old.

Situation: A leak in the Fine Arts building’s HVAC system was discovered when the system continually lost pressure and needed to be filled with water more often than usual. The supply and return lines for the failing HVAC system run below a heavily trafficked service road that could not be taken out of service.

Solution: Nu Flow’s no-dig technology was selected as the only feasible solution for the university. Not only would digging up the pipes for a traditional re-pipe be more costly than the pipe rehabilitation process, but it would take a busy service road out of commission. Nu Flow was able to renovate the leaking HVAC system’s supply and return lines using existing access points, so there was no destruction or disruption.

Technicians used the company’s pull-in-place spot repair liner to cover all leaks. Then Nu Flow’s blown-in epoxy coating was applied to the pipes to serve as a long-term solution against future leaks and other pipe problems.

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Publication date: 10/17/2011