Hour after hour, street after street, a hunt for stray voltage

September 26th, 2009

By Michael McKiernan, National Post

Five nights a week, three converted Ford trucks weave through the streets of Toronto, checking every nook of the city for leaks in the electric infrastructure that can cause stray voltage.

At the controls tonight is Carl Clarke, a supervisor for Toronto Hydro. He oversees the three trucks and two repair crews on call to deal with any problems they identify. In his long career at “The Hydro,” he’s been no stranger to night shifts, so after a cup of coffee and an early evening breakfast, he’s ready to play into the early hours.

“It’s like a giant game of Pac-Man,” said David Kalokitis, chief technology officer for Power Survey Company (PSC), the New Jersey firm that owns and operates the detection trucks for Toronto Hydro. “You have a map and you have to colour in all the streets on the map.”

Toronto Hydro turned to PSC last winter as part of its all-out effort to tackle stray voltage, because of their experience working with Con Edison in New York, where they operate 14 trucks each night.

Following the deaths of two dogs and the shocking of a child in Regent Park last winter, all 600 Toronto Hydro workers were reassigned to inspect every one of the city’s 13,000 handwells, while PSC brought seven trucks to complete a speedy scan of the city. The project wrapped up at the beginning of March with the total bill coming to more than $14-million.

Mr. Clarke has been honing his skills over seven weeks on the job, during which time he has gobbled up the dots on 45% of the city’s streets. The project started with just one detection truck, but with winter fast approaching, when wet and salty conditions make shocks more likely, Toronto Hydro added two more and now expects a full sweep of the city to take three months in total.

Then, just like the arcade classic, the game begins all over again. Tanya Bruckmueller, a Toronto Hydro spokesperson, says the detection trucks have become a permanent feature, expected to devour between $3-4 million each year as part of the corporation’s regular maintenance budget.

“It’s the nature of the beast with contact voltage that you could scan today, but come back tomorrow and find something new, depending on the weather and a number of other factors. Now that we know we have it, it’s always going to be there,” she said.

Ms. Bruckmueller said the stray voltage hotline still gets about one call per month from members of the public who fear their animals have been shocked and she expects that figure to rise in the fall.

“People are overly sensitive now after the incidents last winter, which is not a bad thing. We always send out a crew, but we haven’t detected any voltage,” she said.

Mr. Clarke departs Toronto Hydro’s Scarborough trouble response site at 8 p.m. and by 8:30, he’s close behind the detection truck as it edges down Bathurst Street. Anything over 30 km/h is too fast for the equipment to work.

“The nice thing when you get to 2 a.m. is there’s none of this,” he said, pointing to the line of traffic ahead of him and the steady stream of irritated-looking late evening commuters passing his slow-moving convoy.

The detector itself is a large white appendage to the back of the truck, dotted with red LED lights along its length and secured by a triangular frame. Combined with the permanently flashing orange lights on top, the truck is a colourful, conspicuous sight on the road.

“When you’re driving behind it for hours, it’s almost mesmerizing. I had one guy tell me to have them turn it off one night because he thought he was going to go have a seizure,” Mr. Clarke said.

Inside the PSC truck, the detector makes a low buzzing noise, not unlike a Pac-Man sound effect. The pitch peaks when an electric field is detected and two surveillance cameras attached to the back of the truck allow the operators to pinpoint the equipment that caused the noise.

“We’re looking for any structure that the public can touch, and get a shock off. We sweep up everything and then pass it on to Toronto Hydro and they deal with it,” Mr. Kalokitis said.

That means the sweep has found energized equipment belonging to other utilities, businesses and even private homes. One family got a 1:30 a.m. wake up call when their garage door produced a huge reading on the detector.

“We were scanning a laneway one night and found this door was energized at 100 volts,” Mr. Clarke said. “They weren’t very pleased, but we have a responsibility not to just leave it. 100 volts could do some serious damage.”

The extreme sensitivity of the detector allows the crew to find as little as one volt on a surface within 10 metres of the truck. Toronto Hydro says the Electrical Safety Authority tolerates anything up to 10 volts, but they are reporting and fixing anything more than one volt. Mr. Clarke says there are no typical nights. On a recent quiet evening they found just six instances, but another outing days later caught 17 energized structures on one street.

“If you can fix them when they’re low voltage, that’s a lot better than waiting until they’re higher,” he said.

On Bloor Street, outside Varsity Stadium, the PSC truck stops and within seconds, technicians Darnell Howard and Danny Borras have coned off their vehicle. Spreading out with hand-held voltmeters, they test every traffic light, billboard and lamppost in sight, dodging traffic to get a reading on a manhole cover. This time it’s a false alarm.

“Not all of them are real, but they’re trained to be thorough. There are no quotas,” Mr. Kalokitis said as his team clambered back into the truck, ready to tackle their next street.

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