Houston PolyTank Introduces MagnaPlast™ Monolithic HDPE Sanitary Sewer Manhole System

Factory-assembled, project-engineered HDPE manhole system delivers corrosion resistance, simplified installation and long-term wastewater reliability.

HOPKINS, MO, UNITED STATES, October 6, 2026 /EINPresswire.com/ — Houston PolyTank today announced MagnaPlast™, a monolithic high-density polyethylene (HDPE) sanitary sewer manhole system engineered and manufactured in the United States for municipal and industrial wastewater applications.

MagnaPlast™ is a complete, factory-assembled sanitary sewer manhole system. Each project-specific system is manufactured as one coordinated assembly—not a collection of separate field-assembled components—and delivered jobsite ready for installation. Houston PolyTank collaborates with INFRASTRUCTURE DYNAMICS to configure each system for site-specific structural, hydraulic, groundwater, access, and installation requirements.

The factory-configured system includes the monolithic HDPE barrel, rotomolded base and flow channel, pipe connections, threaded adjustable riser, top plate, access-transition components, and other project-specific features. Components are assembled and leak-tested before shipment, shifting critical fabrication and coordination work from the jobsite to a controlled manufacturing environment.

MagnaPlast is designed in accordance with applicable ASTM HDPE manhole design requirements and manufactured using qualified thermoplastic fabrication and welding practices. The system is designed for installation using familiar underground-utility construction practices, subject to project plans, approved installation procedures, and Houston PolyTank requirements. MagnaPlast is available in both traffic-bearing and non-traffic-bearing configurations, providing flexible solutions for a wide range of installation environments and site requirements. Learn more about the system’s design, construction, anti-flotation features, and project-specific configurations in the complete MagnaPlast™ HDPE Manhole System Overview.

“Municipalities, particularly smaller and rural communities, are under increasing pressure to maintain aging wastewater infrastructure with limited budgets and personnel,” said Ron Elkana, CEO of Poly Holdings and Head of R&D at Houston PolyTank. “MagnaPlast is not simply a different manhole material. It is a complete, factory-assembled, project-engineered system designed to help utilities address corrosion, simplify installation, and support long-term wastewater infrastructure reliability.”

Key Advantages
– Monolithic HDPE construction: Corrosion-resistant virgin HDPE barrel manufactured by spiral-wound solid-wall extrusion and designed in accordance with applicable DVS 2205 requirements, with no longitudinal seam or welded profile joint.
– Complete factory-assembled system: The monolithic HDPE barrel, rotomolded base and flow channel, pipe connections, threaded adjustable riser, top plate, access-transition components, and other specified features are configured, assembled, and leak-tested before shipment as one coordinated system.
– Project-engineered configuration: System details are configured for project-specific structural, hydraulic, groundwater, access, and installation requirements, including inlet/outlet locations, elevations, diameters, and orientations.
– Factory-filled rotomolded base: A flat-bottom HDPE base with structural gussets and concrete permanently encapsulated within HDPE. The base and flow-channel configuration are designed to support wastewater flow and project-specific structural requirements.
– Integrated anti-flotation system: Where site conditions require anti-flotation support, the factory-filled, HDPE-encapsulated rotomolded base works with a separate 7-foot HDPE concrete-fill foundation tub. After the system is set to line and grade, the tub is field-filled with specified concrete to add ballast and base-floor stiffness and help resist external hydrostatic pressure, groundwater-driven uplift, and lateral movement.
– Configurable access and loading options: Direct-mount frames and grade-ring configurations are available for specified frame-and-cover assemblies and project loading requirements, including H-20 / HS-25 traffic-rated applications where configured.
– 100-year design service life: MagnaPlast is designed for a 100-year service life when properly installed and operated within intended service conditions.

MagnaPlast builds on earlier HDPE wastewater manhole configurations that have been deployed in the field since 2019. One early HDPE installation at CJ Bio America, Inc. has remained in service for more than six years in an aggressive industrial wastewater environment, providing field insight for the development of the MagnaPlast platform.

“MagnaPlast brings material selection, manufacturing, structural engineering, and factory assembly together in one coordinated manhole system,” said Dan Early, P.E., Chief Engineer at INFRASTRUCTURE DYNAMICS. “Houston PolyTank and INFRASTRUCTURE DYNAMICS collaborate on project-specific engineering customization and installation support, so each system is configured for its site conditions, hydraulic requirements, and long-term operating needs.”

About Houston PolyTank
Houston PolyTank is a U.S. manufacturer of engineered polypropylene and HDPE structures for municipal and industrial applications. The company designs and manufactures custom storage tanks, process vessels, pressure vessels, secondary containment systems, and monolithic sanitary sewer manholes using advanced extrusion wound technology. Houston PolyTank’s patented and patent-pending manufacturing processes and product innovations are designed to provide corrosion resistance, structural integrity, and long-term reliability in demanding industrial and municipal environments. Houston PolyTank participates in leading industry organizations, including the National Rural Water Association and Environmental & Water Resources Institute of the American Society of Civil Engineers.
MagnaPlast™ is a trademark of Houston PolyTank, LLC. MagnaPlast™ and its integrated Anti-Flotation System incorporate proprietary structural and manufacturing features that are patent pending under U.S. Patent Application No. 63/789,260.

About INFRASTRUCTURE DYNAMICS
INFRASTRUCTURE DYNAMICS is an integrated infrastructure company that provides engineering design, product development, and technical services for municipalities, utilities, and industrial clients across North America. As Houston PolyTank’s strategic engineering partner for MagnaPlast™, the company collaborates on project-specific engineering customization and installation support. INFRASTRUCTURE DYNAMICS also designs thermoplastic lift stations manufactured by Houston PolyTank.

Karen Patterson
Houston PolyTank
Karen@HoustonPolyTank.com

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