There’s a robot in your water pipe (to look for cracks)

The PipeDiver, a robot that uses cameras and electromagnetic pulses to detect structural weaknesses in concrete pipes. | Photo by Boris Ladwig

Part of an occasional series on robots, AI and automation.

A 6-foot-long, high-tech robot snaked its way through 1.2 miles of a 48-inch diameter water pipe near Holzheimer Lane Tuesday morning, pinging electromagnetic pulses off metal in the concrete to detect structural weaknesses.

Sensors on the robot, called PipeDiver, capture the pulses as they bounce back from wires in the layers of concrete. The wires provide compressive force for the pipe. When they fail, they may compromise the pipe’s structural integrity, which can lead to a leak and, eventually a water main break.

The robot consists of three modules, allowing it to bend around angles of up to 90 degrees. Its high-tech equipment, which also includes a lighting array and three cameras, stands in stark contrast to its rather low-tech propulsion system: water pushes the robot forward at about two feet per second, or about 90 percent of the water flow velocity, thanks to the machine’s fins and a circular plastic “sail.” The fins keep the device aligned and prevent the water from smashing the robot into the concrete.

Bill Barloon, program manager of Pure Technologies, explains how the PipeDiver inspects water pipes. | Photo by Boris Ladwig

Louisville Water Co. since 2009 has been contracting with Pure Technologies, which owns the PipeDiver, to detect potential water pipe problems early to avoid costly and inconvenient breaks and repairs. Canada-based Pure this year became a division of $5 billion global water tech company Xylem, of Rye Brook, N.Y.

Before PipeDiver and other Pure tech, such as a Smart Ball that captures sound while swooshing through metal pipes, local water company officials essentially had no way to detect structural weaknesses before leaks or breaks occurred.

“When this technology became available, we jumped on it,” said Kelley Dearing Smith, the water company’s vice president for communications and marketing.

The system in Louisville includes about 4,200 miles of pipe, including about 200 miles of water mains with a diameter of 20 inches and more.

Jeremy Raney, the water company’s infrastructure planning manager, said that when water rushes through the pipes, it can cause vibrations, which can damage the pipes over time. Kentucky’s corrosive soil, too, can corrode the wires that keep the concrete pipes structurally sound.

Water company officials for this year have budgeted $1.5 million in work from Pure to inspect 13 miles of water mains, about 6.5 percent of all the mains in the city. Since 2009, Pure has inspected about 75 miles of local water mains.

Raney said the data that Pure has collected have prevented nearly 100 water main breaks in Louisville, which cost, on average, about $1 million. Instead, the water company has spent about $29 million on repairs.

And Timothy Kraus, Louisville Water’s vice president of production operations, said that when the PipeDiver detects a structural weakness, repair crews often can improve the pipe’s structural integrity from the outside, which means that even during repairs, water can continue to run through the pipes.

The early detection reduces the number of catastrophic failures, such as the 48-inch water main break at Oak and Clay streets in December. The roads flooded, and it took repair crews hours to just isolate the damaged section and to turn off more than 60 valves, each of which can require more than 900 full turns.

The water main break at Oak and Clay streets in December. | Courtesy of Louisville Water Co.

The money that the company saves by avoiding costly repairs allows it to invest more in replacing old pipes, some of which date to President Abraham Lincoln. The pipe that Pure inspected Tuesday was installed in the 1970s and is part of a pipe that delivers water from the Crescent Hill Water Treatment Plant to the eastern part of Jefferson County.

The water company spends about half its capital budget on renewing its assets.

Raney said that Louisville Water schedules about one inspection per pipe per decade, though it may shorten the interval if an inspection shows potential problems. Comparing data from two PipeDiver scans also allows water company technicians to determine where problems are likely to occur.

Water officials told Insider that they cannot perform such inspections in-house, in part because the PipeDiver and Smart Ball technologies are patented and owned by Pure. And, they said, they contract with Pure on a per-job basis only about two months out of the year, which means that even if they could acquire the technology, the limited use would not warrant the expense.

Pure Technologies, which employs 600, conducts water pipe inspections all over the globe and just this month opened an office in Louisville.

Other parts of Insider’s Rise of the Robots series: