Moist air plays havoc with power lines

Winnipeg Hydro pole fires occur when moist, foggy air enables arcing across cracked insulators, causing outages, traffic light failures, pressure dips, and rerouted loads across North Kildonan, King Edward Street, and downtown.

Damp, foggy weather is causing problems for Manitoba Hydro.

"Because the air is very moist, electricity is already going through power lines and it can arc across to an insulator and create a situation where an actual fire can start," said Hydro spokesman Jim Peters.

The problem is impossible to predict, and in other incidents faulty sprinklers have been blamed, but is more likely to happen when there are small cracks on the pole top insulators, he said.

One such fire happened March 4 on a pole in the northeast part of the city on Wenzel Street.

Two more fires broke out on poles located along Route 90, also known as King Edward Street in the city's West End.

The fires are usually pretty minor but crews have to hustle to replace the components at the top of the poles, or eventually replace the pole itself, Peters said.

The fires did not amount to anything but the one on March 4 caused a ripple effect throughout the city.

It broke out about 5:15 a.m. As a result, traffic lights were out throughout much of North Kildonan during the morning rush hour, leading to a long wait for power for many commuters.

The problem also affected the flow of power to the downtown area, Peters said.

Even as Manitoba electricity demand has shifted during the pandemic, Hydro transferred power to the downtown by rerouting the load to another line.

The bump in power also caused water pressure to dip in some neighbourhoods, and a burst water main can trigger comparable outages in big cities, as electric power is needed to operate the city's three water-pumping stations.

As well, the outage triggered a glitch with computers at Manitoba Public Insurance, meaning motorists wanting to renew their driver's licenses were delayed as forms had to be filled out by hand.

All 306 Autopac outlets across the province were affected by the malfunction.

And several stores along a stretch of Henderson Highway were forced to turn away customers because businesses during a blackout often cannot process payments when the lights and cash registers were out.

Traffic light outages continued to be a problem through the evening rush hour as residents coped with blackouts and the problem lingered, prompting police to manually direct traffic at many intersections.

It marked the 11th consecutive day the Winnipeg area has been shrouded in fog and CBC meterologist John Sauder said it could hang around for a little longer yet as mild weather is expected for the rest of the week.

"There's just a lot of melting going on so [there's] a lot of low level moisture, and on top of that we have a surge from the south at the surface that is bringing in more moisture," he said.

"As temperatures cool at night, the air just can't hold the moisture and it condenses out. Fog is basically a cloud sitting on the ground, so that is what we have been dealing with."

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