Columbia Precast Products has produced 100’s of buried infrastructure products for both the Washington State Department of Transportation and the Oregon Department of Transportation. Utility vaults, stormwater catch basins, and manholes built to exact specifications for large municipal jobs as well as upgrades or retrofits.

There are a few advantages of using precast products for these types of products. For one, the pieces are ready for installation as soon as the excavating is complete. Precast concrete can be created well before the deadline and delivered when the city, county, or state needs them. Instead of waiting for concrete to strengthen at the site with pour-in-place concrete, the project can move ahead almost immediately.

Concrete is also the strongest building material in the world, built to last up to one hundred years. This saves money in the long run, cutting down on repairs and maintenance. Concrete is stronger than plastic, is resistant to rust, and repels animals infestations. We also use antimicrobial additives to combat microbial induced corrosion. This protects your investment from the inside!

Perfect Base Manholes

Precast concrete is also more versatile than you might think. Columbia Precast Products manholes, such as the 48-inch manhole monobase can be equipped with Perfect Base technology. This allows improved sewage flow throughout the system because grooves in the base are designed to match perfectly with sewer pipes that bring waste in and takes it out.

No matter if a manhole is a junction for two, three, or more lines, a Perfect Base can be built to match the existing lines or lines that are being buried for the first time. Because the flow lines are built to fit the project, there are fewer opportunities for snags, blockages, and other instances that can create a hazardous situation.


The 48-inch Manhole can be built in many different configurations the base ranges from one-and-a-half feet to eight feet. Additional sections can be created from one to 8 feet. As additional sections are needed, rubber gaskets and mastic joint compounds are used to seal the pieces.

Flat manhole tops are eight inches high and are covered with iron frames and covers. This part of the manhole can be the traditional seven inches tall or three inches tall for suburban applications. If needed, Columbia Precast Products can add ladders or rungs during the casting process for easy access to the line.

If you have a large public or private that requires buried infrastructure, consider Columbia Precast. Not only do our crews have decades of experience, but we were also the first buried infrastructure plant to earn SMaRT certification. So when you work with us, you know you’ll be getting durable products when you need them from an environmentally sound company. Contact us today.

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