ULTRA FLO is a spiral rib pipe with a smooth interior that is the industry alternative to reinforced concrete pipe. The smooth interior improves hydraulic capacity while the exterior box ribs provide structural strength. ULTRA FLO weighs less than 10% of reinforced concrete pipe and comes in longer lengths, greatly reducing handling and installation costs.

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Lower Cost Alternative to RCP Storm Sewer Pipe

ULTRA FLO®, a pipe with a smooth interior, is the material of choice for storm sewer applications and a lower cost alternative to reinforced concrete pipe. The smooth interior improves hydraulic capacity (Manning’s “n” = 0.012, equal to concrete pipe) while the exterior box ribs provide structural strength.

ULTRA FLO is available manufactured with a variety of coatings such as, aluminized, polymer-coated, and aluminum material to meet a wide variety of environmental and service life requirements. For projects with limited headroom, ULTRA FLO is available in pipe-arch.

Because ULTRA FLO weighs less than 10% of concrete pipe, handling and installation costs are greatly reduced. Aluminum ULTRA FLO has only 1/35 the weight of concrete pipe.

Lower labor costs also result from fast and easy joining. Contech Quick Stab® joints or coupling bands do not require special skills or tools. Twenty-foot standard lengths mean fewer joints and faster laying.

Shop-fabricated fittings save installation time in the field while providing hydraulically efficient junctions.

ULTRA FLO Pipe Features and Benefits


Smooth Interior

Manning’s “n” = 0.012, equal to concrete pipe

Exterior box ribs

Shown to be equivalent to reinforced concrete pipe

Weighs less than 10% of reinforced concrete pipe

Easier to install, faster installation

Longer lengths than reinforced concrete pipe

Fewer joints, faster installation, reduced cost

QUICK STAB and coupling banded joints

No special tools or skills required, faster installation, reduced cost

ULTRA FLO Pipe Coatings

  • Galvanized Steel - Pipe made from steel coated with zinc to extend service life. The most widely used and most economical metallic coating for corrugated steel pipe.
  • Aluminized Steel Type 2 - Pipe made from steel that has been hot-dipped in commercially pure aluminum; offers 75 years or more of maintenance free service life.
  • Aluminum Alloy – Pipe made with CORLIX® aluminum provides a predictable service life of more than 75 years; ideal for municipal storm sewers, underground stormwater detention systems or any standard drainage project that must withstand corrosive environments.
  • Polymer Coating – Steel pipe with a heavy-gage polymer coating; protects against abrasion and corrosion to provide a service life of 100+.

ULTRA FLO Pipe Properties

  • Diameters 18”-120”
  • Wall thicknesses of 16, 14, 12, and 10 gage
  • 3/4” x 3/4” x 7-1/2” continuous rib corrugation
  • Standards lengths are 20’-40’

ULTRA FLO Pipe Shapes

  • Full Round – recommended for most applications
  • Pipe-Arch – used in limited headroom conditions. The low, wide pipe-arch design distributes the flow area horizontally, providing hydraulic capacity without lowering the grade.

ULTRA FLO Pipe Accessories

ULTRA FLO Pipe Applications

  • Culverts, canals and ditch enclosures
  • Storm sewers
  • Stormwater Detention
  • Reline for drainage structures and culverts

Technical information for this product is centrally located in the technical guides section.

View Technical Information
CMP Pipe for Wind Turbine Foundations and Vertical Shafts

Contech large-diameter CMP is used as a deep foundation form at the base of the windmill. CMP is placed vertically to act as a form for the poured-in-place concrete foundation.

CMP for Culverts, Canals and Ditch Enclosures

Our corrugated metal pipe is the most durable, economic, and widely chosen material for most drainage culverts applications. With a variety of CMP products including helically corrugated HEL-COR® and spiral wound ULTRA FLO®, Contech offers engineers and contractors flexibility in designing drainage solutions to best fit their projects’ exact requirements.

CMP and PVC Pipe for Pipe Reline

Lining inadequate or failing structures with corrugated metal material or plastic pipe uses little of the available area, thereby preserving the maximum amount of the original opening. Due to the hydraulic efficiency of Contech products, often a smaller structure provides the same hydraulic capacity as the original because of the low Manning “n” factors of A-2000™ and A2™ Liner PVC pipes and HEL-COR® and ULTRA FLO® CMP. Existing culverts and arches are generally lined with structures of the same shape, though slightly smaller in size. Rectangular openings can be lined with round, elliptical or pipe arch structures. Corrugated metal structures can fit almost any existing shape.v

ULTRA FLO for Storm Sewers and Drainage Pipe

No other storm sewers or drainage pipe structure offers the range of structural strength that’s available with ULTRA FLO® - which continues to perform where rigid pipe fails. We offer coatings and linings that will provide a minimum of 75-year service life for most soil/water conditions. ULTRA FLO provides a Manning’s “n” = 0.012, equal to concrete pipe and other smooth wall drainage products. There are custom fittings and coatings to meet your project needs.

The Contech Advantage

Agency/Regulatory Guidance

Our team is ready to provide you with expert advice and assistance on local regulatory requirements, resulting in faster approvals.


Solution Development

Our engineers can review your requirements, weigh all options, and recommend the optimal solution to integrate with your site designs.

Technical Expertise

Our engineers can assist by providing product specific engineering calculations such as hydraulics, buoyancy, foundation reactions, and unit sizing.

Cost Estimates

We can quickly provide engineer’s cost
estimates to assist with your solution
selection process.

Site Specific Drawings

Our engineers can provide site-specific drawings for proposals, project meetings, and submittals, helping you be more efficient with your time.

On-site Assistance

Contractors know time is money, so we provide preconstruction meetings, delivery coordination, and on-site installation support to ensure a timely, smooth installation.