Columbia News

The City of Columbia Sewer Utility continues to complete improvement projects to rehabilitate the sanitary sewers across Columbia.

Some of the Utility’s aging pipes are cracked or broken, nearing the point of failure. Rather than replacing sewer lines, the Sewer Utility repairs and restores the sewer pipes using a method called cured-in-place-pipe (CIPP).

CIPP rehabilitation involves inserting a resin-saturated liner into the existing pipe then curing it with steam. The cured material bonds tightly to the inner walls of the existing pipe, creating a pipe within a pipe that can last up to 80 years.

City of Columbia crews need to ensure a sewer main was clean and free of debris so a new lining can adhere to the pipe.

During a recent day, the Sewer Utility’s Nathan Runyan, engineering supervisor, and Eric Ingram, project compliance inspector, were overseeing a $7 million rehabilitation project to the vitrified clay pipe sewer trunk in the Bear Creek watershed – in the area from Rangeline to Route B.

Contractor crews had already bypassed the sewer main under construction, rerouting wastewater and other water through different piping. This was to make it where they could do their work without having to turn off water in the surrounding area.

The late morning sun was beating down on a group of men in fluorescent yellow and orange shirts crowded around a manhole. Crews needed to ensure the sewer main was clean and free of debris so the lining can adhere to the pipe.

One of the workers slowly lowered a motorized camera and a hose down the manhole. Inside the back of a white truck, another worker positioned himself in a small office space with two monitors and equipment to maneuver the camera through the pipes.

When obstructions were spotted, the hose snaked through the pipe, water blasting out of the nozzle and power washing away debris.

Using an air pressure machine, City workers insert a long piece of lining down into the manhole and through the pipes.

Once the main was sufficiently cleaned, the camera and hose were pulled out of the manhole. A different truck pulled up to the manhole, carrying crates covered in a dark tarp. Packed inside ice-filled crates was new lining that would fortify clay pipes. Because liner begins to cure quickly, it has to be stored in ice to remain flexible.

In its pre-insertion state, outside liner looks like plastic while inside is fiberglass-and-resin material that will eventually cure to pipe.

Using an air pressure machine, workers inserted long piece lining down into manhole through pipes. Two workers fed liner into manhole while one kept cold air on lining another monitored temperature liner.

Digging up disconnecting replacing 300 feet sewer main can take two three weeks.

Liner inverted as placed – like turning sock inside-out. Once set workers used steam heat hardening fiberglass-and-resin adhering it pipe.

Digging up disconnecting replacing 300 feet sewer main can take two three weeks CIPP method covers same distance two three hours without shovel touching ground

Efforts rehabilitate existing infrastructure part Wastewater Stormwater Integrated Management Plan CIPP projects completed across Columbia including downtown along Business Loop Bear Creek watershed

Integrated Management Plan outlines strategies City meet critical utility needs address regulatory requirements Five years Utilities updating plan target investments critical areas such public health safety quality life sustainable services regulatory compliance water quality City streams

For more information visit CoMo.gov/IMPsurvey