Running beneath our feet are 2,200 miles of pipes that bring water to nearly a million customers across Portland. Over such a large footprint, there are bound to be subterranean leaks every now and then.
Locating and fixing them in a timely manner is critical. Even small trickles can cause sizable issues, like potholes and damage to sidewalks. Of course, minimizing waste is also vital to sustainability.
Traditionally, the Portland Water Bureau has searched for areas of water loss using acoustic equipment, shooting sound waves into the ground to listen for certain indicators of pooling water.
But in the summer of 2021, it partnered with ASTERRA to conduct a satellite leak detection pilot program. By firing ground-penetrating radar from 390 miles above Earth, the company can search for signatures unique to treated drinking water, like conductivity and traces of chlorine. It’s similar to the technology used to look for water on Mars.
During the four-month trial, 160 leaks were found — three times what the leak detection team normally finds in an entire year. Of those breaks, 95% were not actually visible from street level.
All told, the Water Bureau estimates that 338 million gallons could be conserved per year. That’s like turning on your tap for almost 22 minutes, with the entire Willamette River flowing out of it.
To be sure, the utility manager will conduct a phase-two test this summer; if the results are again convincing, it will consider adding this emerging technology to its tool belt in order to save customers money.