A humming, high-tech “RAT” is saving time and money by finding blocked sewer lines – and getting some curious stares, too.
“People hear us and say, ‘What is that thing?’ ” said Augusta Utilities Department worker Tyrone Brown, who operates the city’s new SL-RAT, which stands for Sewer Line Rapid Assessment Tool.
The device, which arrived three weeks ago, uses an ascending series of loud musical tones to determine the amount of free space in the sewer pipe.
“This tells us in less than three minutes if we need to devote up to 45 minutes cleaning the pipe, or if we can move on without cleaning the pipe,” said Jody Crabtree, the department’s asset manager. “It will find anything that disrupts the flow in a sewage pipe.”
One of the department’s perennial challenges is maintaining 950 miles of sewer lines that transport 30 million of gallons of waste to the city’s Messerly Treatment Plant each day.
Cleaning crews can cover more ground using the RAT because it eliminates lines that are clear, allowing resources to be focused where they are needed.
“We can assess the level of debris in pipes in an entire neighborhood in a matter of a few days where it would take us several days or weeks to devote a truck and crew to cleaning all of the pipes before this tool,” Crabtree said. “It’s amazing to see how far technology has come along.”
The $18,000 device, developed in North Carolina and marketed by Charlotte-based InfoSense, is portable and simple.
Operators place a transmitter in one manhole and a receiver in the next one down the line. After a few octaves, it gives the operator a numeric score that gauges the level of obstruction.
Blockages occur frequently and can cause overflows that
are messy to clean up and can result in costly environmental fines.
Grease is one of the primary culprits.
“It’s liquid when it goes into the line, but it becomes solid when it cools,” he said. “Once it starts to build up, the blockage gets larger and all it takes is something going through the pipe that gets stuck – and you have all that sewage coming out a manhole somewhere.”
The tool will not replace other assessment methods, such as tiny cameras, but makes line maintenance easier.
Brown and his colleagues sometimes wear earplugs while using the RAT. “And we don’t turn it on early, not till after
9 a.m.,” he said.