Giant cockroaches, rats are most common sewer pipe residents
It’s a dirty job, but somebody has to do it.
That was the consensus of Public Works Superintendent Wallace Tomlinson and Southeast Pipe technicians when The Times caught up with crews cleaning and TV’ing city sewer lines earlier this month.
The lines were teeming with cockroaches significantly larger than the ones that sneak into area homes occasionally when the weather changes. Those creepy critters scattered as a camera inched its way through the line.
Another Southeast Pipe employee had already cleaned the sewer line out ahead of the camera.
“You don’t want to put your camera in a dirty line,” Tomlinson says. “He can run approximately up to 1,500-2,000 psi (pounds per square inch) of water pressure on the backside. It pushes the air in front of it and sucks everything back to it which helps to clean your sewer laterals back to the main line.”
The roaches remain — even after that colonoscopy of the sewer line — but damage to the pipes is much easier to see in a clean line.
TV Technician Ashley Thornton and Tomlinson were looking for cracks, leaks and evidence of groundwater infiltration, carefully documenting them from the back of a van parked on Pittman Street.
“Mainly your cracks, your breaks — anything that’s got infiltration which is groundwater coming in to it,” Tomlinson says. “It’ll look like someone turned on a water spicket at a joint.”
It took crews 20 minutes to clean the line and less than an hour to TV 436 feet of line on Pittman Street. Thornton says that varies depending on how dirty a line is.
Southeast Pipe has TV’d more than 15 miles (80,000 feet) of city sewer line in the last six months, documenting damaged pipe in every city district, particularly areas where the city receives frequent calls for sewer backups, slow drainage or reports of sinkholes.
“Those are telltale signs something might be wrong with the pipe,” Tomlinson says.
So far, the work in Blackshear has been typical — roaches have been the most frequent visitors to pop up on Southeast Pipe’s camera feed. But, Tomlinson and the other technicians recall finding much weirder stuff in their years TV’ing sewer lines.
Alligators, rats, turtles, fish, goldfish — live ones — to name a few. They’ve also found guns, money, drugs and golf clubs before. Tomlinson found a gold ring worth $16,000 in an Atlanta line once.
The data collected from this project will be used to help prioritize sewer improvement projects the city intends to complete in conjunction with ongoing construction of a new wastewater treatment plant.
Each break or damaged pipe will be graded on a scale from 1-10.
“Anything over a 5 grade score is higher priority — over 50 percent chance of failure,” Tomlinson says.
The city will then weigh those gradings against the cost of each sewer repair as well as the cost of road repair once the line has been replaced. Sewer improvement projects are closely coordinated to road resurfacing projects to eliminate patching a newly resurfaced road.
Blackshear secured a $6.6 million loan and $2 million grant from United States Dept. of Agriculture (USDA)for the work. Approximately $390,000 was budgeted for Southeast Pipe’s TV’ing project. To date, the city has spent $254,167 for the TV’ing of lines.
The Pittman street pipe, a 6” clay pipe similar to terra-cotta, was most likely installed in the late 1960s. Those 6” pipes will eventually be replaced with 8” pipe through a process called bursting to allow for more capacity as neighborhoods grow and more residents tie in to the lines. A pneumatic hammer busts the old pipe and a winch pulls in new, larger pipe right behind it. The clay remains of the old pipe are left to decompose in place.
Thornton, who’s been the cameraman behind 50,000 feet of city sewer pipe, estimates 75 percent of what he’s surveyed so far is 6” pipe.
Bursting won’t be used for repairs to 8-10” pipelines though. Those pipes will be cured in place with a fiberglass tube. It’s rolled inside the old pipe, essentially lining it with a brand new pipe, through water or steam inversion. City crews won’t have to dig out the old pipe.