Manholes play an important function for any large, buried infrastructure operation. They provide access for workers to clean, maintain, and repair sewers and drainage pipes. Imagine trying to clean out sewer pipes or remove blockages from one end or the other. That would have to be one industrial length snake!

Suffice it to say, sewer systems would not be run very efficiently if there were no access points along the way. In fact, manholes being manufactured today are making sewer lines even more efficient. Products such as Perfect Base are inserted into the bottom of manholes to smooth the transition between manhole and sewer pipe. Some manholes are created with channels already in place.

These inserts are built to match the existing sewer pipes. Think of it as a large piece of clay in the bottom of the manhole that had a pipe pushed into it vertically. When the pipe is removed, there would be a rut left behind that matched the incoming pipe. The sewage just continues on unabated.

In the past, the floor of the manhole was flat. So workers would go into the manhole and try to create this furrow by hand. This led to debris getting caught at the edges and large blockages were formed. These base inserts remove much of that worry.

Manhole bases can be made up to eight feet high and just under 6 feet wide with additional manhole sections extending the height to 16 feet. At the top sits a cone that is covered by a manhole cover, those round pieces of metal you see in the middle of the street every few blocks. Each joint is outfitted with a gasket to prevent leakage.

Columbia Precast Products has created thousands of manholes of varying sizes for varying projects. Whether these manholes are used in public thoroughfares or private property, each has to follow exact specifications, especially when being retrofitted.

Installing a sewer system in a new neighborhood, business park, or other projects that involve manholes? Contact us for an estimate. We are a SMaRT Certified precast concrete company which may address any environmental needs your job may require. We have worked with both the Washington and Oregon Department of Transportation and are familiar with all specified codes. We look forward to hearing from you.

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