High-Flow Bypass Manholes have a pre-treatment vault used to separate sediment and bypass the treatment vault during heavy rain and runoff events.

Features & Benefits
  • Modular Construction
  • Base/Bottom Section
  • Top Sections
  • Manhole Coatings
  • Material and Design Load Specifications
  • Grade Rings and Risers
  • Cones
  • Flat Slabs
  • Block-outs and Cored Holes
  • Offers immediate accessibility to maintain and inspect the critical infrastructure
  • Customizable sectional design
  • Quick and easy install
  • Provides housing for critical infrastructures
  • Connection and access pint for maintenance and inspection
  • Cylindrical or rectangular available
  • Integral floor (body sloab) optional
  • Available extended base bottoms increase stability
  • Cover and protect
  • Maintenance and inspection accessibility
  • Variety of sizes available
  • Water-based damp-proofing, epoxy-based chemical resistant, and other coating options are available upon request
  • Meets the following criteria:= ASTM C 478 specifications= AASHTO HS-20 live load criteria= NPCA & ACPA certifications
  • Elevate access opening covers to grade
  • Available in rectangular and round shapes
  • Section to reduce the manhole diameter to the cover and frame diameter
  • Concentric or Eccentric shapes
  • Variety of sizes available
  • Typically used for very shallow manholes
  • Large diameter manholes are covered with structural flat slab covers designed to resist the applied dead and live loads
  • Variety of sizes available
  • Offered in multiple locations to accommodate various connection sizes
  • Cast-in block-outs and cut-in cored holes are generally placed in the base or riser sections in limited sizes
  • Block-outs available in rectangular and circular shapes
Specs & Guides

Model: Hi-Flow Bypass Manhole - size varies

Material: Concrete

Measurement System:

Height: Variable

Width: 4’

Length: Variable

Diameter: 4’

Weight: 5935 lb


PDF: 020-HIFLOW-9.pdf

DWG: 020-HIFLOW-9-1.dwg

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28499 SW Boberg Road
Wilsonville, OR


(888) 965-3227


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