Modular System Rehabilitates Deteriorated Manholes

Dec. 1, 2018
To improve manhole hydraulics, the city of Davenport, Iowa, utilized RELINER® Modular Manhole Invert Channels to rehab aging manholes in the city.

The city of Davenport, Iowa, has been rehabilitating aging manholes, some of which have deteriorating benches or lack an invert channel, resulting in poor flow conditions with solids remaining in the structure. To improve manhole hydraulics, the city has utilized RELINER® Modular Manhole Invert Channels.

The system consists of molded fiberglass flumes with smooth sewer pipe interfaces that are used to rehabilitate inverts without flow interruption. The field-installed modular components bolt together inside the manhole and serve as the form for a new concrete bench. This system eliminates inconsistencies associated with field-formed concrete channels.

Molded fiberglass flumes rehabilitate inverts without flow interruption.

Initially, the contractor provides internal manhole measurements to document manhole diameter along with the location and size of the inlet and outlet pipes. RELINER® engineering staff utilize the measurements to prepare a sketch of the manhole showing the modular components that are required. Straight sections, bends of varying degrees and lengths, as well as tees, wyes, and pipe end sections are available. The pipe end sections act as the interface between the open channel sections and the pipes.

After manhole preparation, the modular components are assembled and aligned within the manhole. They are held in alignment with flow-through plugs during placement of the concrete bench. The full-depth, high-flow fiberglass channels remain in place and are easy to clean and maintain. Standard 8” and 12” depth channel sections fit through a 24” manhole frame and will accommodate 6” through 12” pipes. Larger sizes are available. WW

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