- Special Projects
Steve Omiya plugs in the leak logger, hooks up the ZCOR and straps on the noise-canceling headphones. It’s Friday morning in front of the Surftech shop on Queen Street, near Ward, and Omiya is listening for leaking pipes underground.
Tearing up the street to check on leaks is cost-prohibitive, and waiting for pipes to break means overtime shifts, gnarled traffic and poorly timed service outages. So the Honolulu Board of Water Supply is taking proactive steps to cut down on main breaks: high-tech listening gadgetry that allows them to selectively target only those pipes they know are already leaking.
Omiya and his partner, Ed Takaesu, are among Honolulu’s most seasoned pipe whisperers. They both have the formal title of “Water Service Investigator,” but Omiya has self-applied a different descriptor — “surgeon,” thanks to the precision the equipment affords them as they identify underground leaks.
“It’ll go within about two feet or less, depending on what type of pipe,” Omiya says. “When you go with PVC or AC, because it really absorbs the sound, there’s more chance of an error, but it’s going to be within, I would say, less than five feet. The machine is that accurate.”
Omiya points to a data table compiled on multiple visits to the area as evidence of a leak underground.
So there’s a scientific component to what Omiya and Takaesu do. Consistently high numbers in this column means a higher noise level. A low number in that column means a “tight” sound with a narrow bandwith — likely a leak rather than background noise. The data’s collected in the middle of the night, when the rest of the world is quiet, and it’s charted to show them how things change over multiple visits to an area.
“It’s a tedious process, but it’s better than a pipe blowing up,” said Omiya, who for years worked on teams reacting to emergency leaks before he started the preventive maintenance. “The proactive leaks are a little harder because there’s no water coming up to the ground, so you’ve got to develop some kind of skill, I would think, to differentiate because we’re not going to just dig all over the place. We’ll be digging a lot of empty holes and that’s not too good.”
So there’s also an art form to what allows Omiya and Takaesu to make precision cuts that make them more like a surgeon instead of a regular family doctor. Omiya marks a spot on the pavement where he says the leak will be found when the crews dig it up. X marks the spot.
He passes the headphones, and I put them on. There’s a light rustling. Is that running water? A generator a few blocks away? Just white noise? To the untrained ear, it’s hard to make sense of it.
Only a handful of Board of Water Supply employees are devoted full-time to the leak detection program. And the experienced guys say they have more success than the newbies. The old-timers have other tools too — things like metal rods that turn when they cross magnetic fields created by pipes and running water in the ground.
The Board of Water Supply sends out crews like Omiya and Takaesu with tools like the leak logger and the metal rod because it’s determined that there’s a solid return on investment. Water Conservation Coordinator Cat Sawai, who runs the program, talks about the “triple bottom line.”
One, the program saves water — more than 500 million gallons per year, BWS estimates. Two, the program provides a social benefit to customers by reducing the impact to traffic and service. Three, it diminishes infrastructure costs, labor and BWS worker fatigue.
“It’s always been around, but we got very active in about 2004 because we started working on water budgets, which is determining how much non-revenue water is in the Board of Water Supply system,” Sawai said. “Now where is it going? Some is legitimate. Some is Fire Department using water. Some is Board of Water Supply practices like flushing lines. … But some are losses, like leaks. So we realized and recognized that that could be a large component of the non-revenue water, and that’s water that could go back to the customer, revenue for the board, and there’s all kinds of benefits to preserving that too.”
“Conservation is the lowest-cost strategy for supply. We look at it as a source of supply,” she said. “When you conserve, you’re saving that water, that’s more supply for you. Then we don’t have to look at more expensive alternatives like desalination.”
Sawai said she wants to expand the program by purchasing equipment to supplement 300 drive-by leak-loggers installed since 2009 and, someday, adding more bodies to the leak detection teams.
The proactive nature of the leak detection team means that the Board of Water Supply can schedule repairs for when it’s convenient — convenient for work crews, convenient for water customers, and convenient for drivers who might otherwise be stuck in traffic — rather than come running when a pipe bursts during rush hour or in the middle of the night.
This cuts down on overtime and on aggravation. When a repair crew returned two days later and dug up the driveway fronting Surftech, the shop was closed as it normally is on Sunday mornings. The owner stopped by to see how things were going, but the plan was to have the pipe fixed and the lot repaved without any impact to his business.
As the crew finished digging, there was a palpable sense of disappointment in the air. No explosions of running water. Not even a visible trickle. Omiya and Takaesu — confident in their ability to find a leak within a few feet — seem to have missed.
“It’s almost an educated guess in a way. And it’s high-tech instrumentation … but sometimes it’s going to come out like this where you don’t hit one,” said Field Operations Division Program Administrator Daryl Hiromoto. “More often than not, they’re correct though.”
The operation wasn’t entirely for naught. A crack in the pipe and wet dirt indicate there may have been a slow leak that could have turned into a major problem before too long.
And at the very least, BWS has a policy to dig up any old galvanized pipe that’s still in the ground, so this lateral from the Surftech shop to the Queen Street water main would have had to come out sooner or later, anyway. Galvanized pipe tends to rust, and this one was highly tuberculated — meaning the insides were clogged with gunk, reducing flow and dirtying the water.
So it was removed, and a new copper pipe was installed in its place. The whole operation only took a few minutes.
In the end, this pipe replacement didn’t contribute to the 500-plus million gallons of water savings the board attributes to its leak detection program each year. It’s a hit or miss operation. Even for surgeons.
Check out Civil Beat’s slideshow from our visits to the Queen Street leak: