For use in areas that need a way to remove standing water, 24-inch manholes are a common solution. These manholes can be equipped with flat grates or “beehive” grates that are rounded at the top. These grates are an ideal answer if your manhole is placed in a swale or depression in the ground to prevent blockages, such as leaves or garbage.

Columbia Precast manholes see a lot of use in parking lots, along roadways, parks, golf courses, and other places where stormwater needs to be removed. While Perfect Base manholes are gaining in popularity within sewer systems, manholes with a monobase are still standard for stormwater control and area drains.

Depending on where the manholes will be placed, the cast iron frames will either be 3” or 7” tall. Columbia Precast 24-inch manholes come in several different sizes, from one foot to eight feet in height. While the opening is 24 inches, the actual width of the manhole is 31 inches (when including the thickness of the manhole wall and grade rings.

Entry and exit points for a monobase can also be cored to your specifications. This is practical for many reasons, such as retrofitting a new manhole in existing infrastructure or custom placement in difficult areas.

However, our 24-inch manhole will still adhere to all ASTM-C478 specifications, requirements, and codes. Columbia Precast Manholes are ready to be installed when you are and can be placed as soon as the excavation is finished. Because they have already been strength-tested, you’ll be able to backfill the same day. For other specifications, consult the .pdf below or click here to download the .pdf.

Sustainable Solutions

Columbia Precast Products was the first buried infrastructure facility in the United States to earn SMaRT certification. This means our products and processes are designed with the environment in mind. We even choose our partners based on distance from our plant. Shorter delivery distances mean less gas and fewer emissions.

The Pacific Northwest is a beautiful place to be – that’s why we chose to set up shop here. But we also live here and want to do everything we can to preserve that natural beauty. If you have a need for one or 100 hundred 24-inch manhole for public or private use, reach out to us. Our quick turnaround times will keep your project on schedule.

24-inch Manhole with Monobase