Tech uses sound waves to find clogged sewer pipes

With more than 800,000 miles of sewer pipes in the United States, wastewater utilities tasked with keeping those pipes clear have their work cut out for them. Now, a small business has developed a quick, cost-effective technology to help keep sewer pipes clog-free.

InfoSense Inc., which received early funding from the National Science Foundation (NSF) Small Business Innovation Research program and is spun out of the University of North Carolina at Charlotte, has commercialized a device that detects clogs based on the transmission and processing of sound waves.

The device, called the Sewer Line Rapid Assessment Tool, or SL-RAT, works by lowering a speaker through a manhole that sends acoustical waves through a pipe to a receiver on the other end. An algorithm processes the signal and determines to what degree clogs or other defects may be obstructing the pipe.

Over 130 cities around the globe are already using the SL-RAT. Due to its ease of operation and speed, the tool can complement and help better focus the deployment of existing robotic cameras and cleaning equipment, which are much slower and more expensive.

(Watch the SL-RAT in action in the hands of City of Rockville, Maryland workers.)

According to InfoSense, utilities can cover between 1,000 and 1,500 feet per day using a camera or a cleaning truck, while the SL-RAT averages between 7,500 and 15,000 feet per day.

Ivan Howitt, InfoSense chief technology officer and founder, says the technology is an elegant example of how innovative new solutions can help industry solve old problems.

The project is one of many examples of NSF-funded research and technology that take smarter, more innovative approaches to making local and national infrastructure safer, cleaner and more resilient.