The Hard-Working and Highly Visible Component of Any Wastewater or Stormwater System

Critical Infrastructure Access

Manholes provide access to underground infrastructure, allowing for inspection, maintenance, and cleaning of pipes, channels, or other conveyance systems.

Built to ASTM Standards

Our manholes meet all ASTM standards related to materials and manufacturing requirements for precast reinforced concrete manhole sections, including bases, risers, and cone or flat tops.

Designed for Safety and Accessibility

precast manholes are designed with safety features, such as slip-resistant steps or ladder rungs, to provide easy and safe access for inspection and maintenance.

Watertight Performance

Designed with tight tolerances and gasketed joints, our watertight manholes reduce the risk of infiltration, exfiltration, and contamination.

Reduce Flood Risk

Manholes can be designed as overflow or bypass structures to handle excess water during high-flow events, preventing surcharging and reducing the risk of flooding.


Made from high-quality, reinforced concrete, ParkUSA precast manholes are durable, structurally sound, and can withstand harsh environmental factors. Often, the most visible component in a sanitary sewer or stormwater system, the manhole provides crucial access and maintenance capabilities for underground conveyance structures.

Made with modular precast components including a base, riser, a cone or flat top, and a lid made of either metal or concrete, each manhole is customized for project and municipal requirements. The base accommodates pipe connections and may feature preformed inlets and outlets for the flow of stormwater. The riser sections vary in height and can be stacked to reach a desired depth, while the cone or flat top provides a smooth transition to the surface level. Our manholes are manufactured in our NCPA-certified plants for consistent quality and dimensional accuracy.

How It Works

A manhole plays an important role in channeling water efficiently in a sanitary sewer or stormwater system. They serve as an access point for inspection and maintenance of underground structures while also providing a means of regulating the flow of water.

A manhole is typically installed at key locations along the sewer line where there is a change in direction or elevation. This helps to ensure that the wastewater or stormwater flows smoothly through the system and does not cause blockages or backups. The manhole allows water to flow into the sewer or stormwater lines through inlet pipes located in the base of the structure. The water then flows through the line until it reaches the next manhole or treatment plant.

Inside the manhole, the flow of water is regulated by various components such as inlet and outlet pipes, a drop manhole, and an effluent filter. These components help to slow down the flow of water and prevent debris and solids from passing through and clogging the sewer system.

During heavy rainfall or flooding events, the manhole can also act as a relief point for excess water. The excess water can be diverted into the manhole and held until the flow in the system subsides.


About the Precast Concrete Sanitary Sewer Manhole

The Model SSMH is a sanitary sewer manhole is made of precast concrete and consists of hollow cylindrical sections with an iron access cover at grade level. The inside bottom of the manhole contains an invert with curved channels that enables efficient flow of the incoming and outgoing piping. Resilient pipe connectors ensure leakproof operation. The manhole is available in different sizes and configurations to meet most application demands, local municipal codes, and ASTM C-478.


Precast manholes are an essential component of any wastewater or stormwater system and provide crucial access to underground conveyance structures.

Sanitary Sewer Systems

Wastewater manholes are an essential component of sewer systems, providing access and maintenance capabilities for underground conveyance structures.

Stormwater Collection

Precast manholes serve as collection points for stormwater runoff from streets, parking lots, and other impervious surfaces, directing the water into the stormwater management system.

Wastewater or Stormwater Treatment

Precast manholes can include sedimentation or filtration components to remove debris, sediment, or pollutants from flow before discharging it into water bodies or infiltration systems.

Municipal Infrastructure

Manholes are used in various municipal infrastructure systems, including water treatment facilities, water storage tanks, water treatment plants, and pump house stations.

Flow Control

Manholes can be integrated with flow control devices, such as weirs or orifices, to regulate stormwater flow and reduce the risk of downstream flooding or erosion.

Pipe Transitions

Manholes facilitate changes in pipe size, direction, or slope, allowing for efficient conveyance of stormwater through the drainage system.

Inlet and Outlet Structures

Manholes can serve as inlet or outlet structures for stormwater detention or retention ponds, controlling the flow of water into and out of these facilities.

Specs & Docs


Precast Concrete Manhole – Storm Sewer (Model PCMHST – 48″ thru 120″)


Manhole – Extra Heavy Duty (Model MHHD)


Precast Concrete Extension Ring (Model GR – 27″ thru 34 1/2″)


Precast Concrete Square Manhole – Sizes 36″ thru 96″


Precast Concrete Manholes and Wet Wells


Transitional Manhole / Stormwater Junction Box


Force Main Discharge Manhole with Corrosion Resistant Liner

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