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Energy Absorbing Manholes

Dig It! Drop It! Done!Fiberglass Manhole with H-20 Highway Loading Reducer Top and Energy Absorbing / Dissipating Baffle and Directional Shoulders A sub-set of our fiberglass flow Diversion Manholes, Openchannelflow has developed Energy Absorbing Manholes for the conditioning and control of open channel flows.  Openchannelflow Energy Absorbing Manholes can be an economical solution to the problem of excessive velocity upstream of flow measurement structures where corrosion resistance, speed of installation, and ease of use are important.  Each unit is single-piece, water-tight, and corrosion resistant; requiring minimal installation time and virtually no maintenance.

As with the Diversion Manholes upon which they are based, Openchannelflow Energy Absorbing Manholes are offered with a variety of manhole cover styles, diameters, and options to tailor them to your specific needs.

Top styles include:

  • Full opening domed top for maximum access
  • Flat cover aluminum hatches for pedestrian areas / low profile installations
  • Large diameter opening highway loading reducers tops (using customer supplied grade rings, cover, and frame)
Each unit comes as a single, watertight piece with the following features:
  • Reinforced composite energy absorbing / dissipating baffle
  • Integral fiberglass shoulders to shape and direct manhole discharge
  • Corrosion resistant interior barrel surface
  • Integrated cover (see above)
  • Closed base
  • External base mounting / anti-flotation flange with cushioning pad
  • Inlet / outlet piping with flexible couplings for quick pipeline connection
  • Exterior corrosion resistant gel coat barrier with U.V. inhibitors

In addition, Openchannelflow offers a wide array of optional accessories to help you customize our Energy Absoring Manholes to fit your specific needs, including:

  • OHSA-compliant fiberglass ladder with non-slip ladder rungs
  • Full and half diameter fiberglass grating platforms
  • General purpose and hazardous location lighting
  • Powered and unpowered ventilation
  • Equipment shelves and mounting panels
Manhole diameters available are:
4’ [122 cm],  5’ [152 cm],  6’ [183 cm],  7’-8” [234 cm]1

1Aluminum hatch and highway loading top styles only.