What is a Flow Metering Manhole Anyway?

Reduced to its most basic elements, a flow Metering Manhole is a fiberglass (FRP) manhole with a factory integrated flow element to measure the flow of water in a pipe. Most Metering Manholes integrate flumes (typically Parshalls), although weirs and magnetic flow meters can also be integrated. As a single-piece, watertight unit, Metering Manholes are great for connecting to new or existing sewer lines where there isn’t an existing manhole or when a flow element is larger than can reasonably be accommodated in some other structure.

Metering Manholes are light-weight (typically ~1/10’ the weight of concrete) and require minimal installation downtime – a real lifesaver for industrial and institutional customers! Simply excavate the sewer line, pour a pad, stop or bypass flow, cut the line, and install the Metering Manhole.

DIG IT. DROP IT. DONE.

Flow can usually resume as soon as the Metering Manhole is connected to the sewer line – even before it has been secured in place or the excavation is backfilled! At a prepared site, installation is quick – requiring only a few hours of downtime – perfect for holiday shutdowns.

Openchannelflow Metering Manholes are built to meet or exceed latest version of ASTM D3753 “Standard Specification for Glass-Fiber-Reinforced Polyester Manholes and Wetwells”.

Standard features include:

Integral manhole cover (Traffic Reducer, Aluminum Top, or Domed Fiberglass Top)
Composite manhole barrel
Corrosion resistant, non-porous interior surface
Corrosion resistant exterior gel coat barrier with U.V. inhibitors
OSHA compliant stainless steel reinforced fiberglass ladder
Inlet / outlet pipe connections (pipe stubs, flanges, caulking collars)
Closed base
External base mounting flange with cushioning pad

In addition to flow Metering Manholes, Openchannelflow offers Grinder, Energy Absorbing, Storm Water, and Diversion composite manholes. Each of these manholes utilize the same composite barrel and cover systems found in our flow Metering Manholes.

For more about what goes into a fiberglass manhole read this blog post.

METERING MANHOLES—LEARN MORE