What looked like special effects on the set of a movie last week was actually phase six of a sewer rehabilitation project in Zachary.

The $14.3 million sewer project includes replacing, repairing and rehabilitating the city’s old sewer collection lines, Department of Public Works Director Chris Davezac said.

In this latest phase of the project, the process included running a special camera through the pipes to locate holes or cracks.

Once identified, workers from Insituform use a cured-in-place pipe product to reline the pipes with composite materials saturated with an epoxy resin, Davezac said.

Then, using water or air pressure, a tube is inserted into the pipe and hot water or steam is circulated to cure the thermosetting resin, which fills any cracks, holes or tears identified in the pipe.

Once cooled, the ends are cut off, and the pipe is returned to service, Davezac said.

“It’s a really neat process and a lot less expensive than replacing the entire sewer system,” Davezac said.