UPDATE: Details On Damage That Caused Blackout

HydroTreeFallAug12

A tree that fell onto a high-voltage transmission line in a remote area was the cause of a major power outage across the Ottawa Valley on Monday, which lasted for up to 15 hours for some customers.

Hydro One tells Pure Country 96.7 it was around 3:00 p.m. Monday when a tree fell onto a high-voltage power transmission line near Bon Echo Provincial Park, in an isolated area off Highway 41 south of the Renfrew County limits.

It set off a fire which badly damaged the line, knocking out the main electricity transmission source that feeds thousands of homes in the Ottawa Valley.

Crews worked all night to repair the damaged line, first taking steps to find the damage and then making sure it was safe to access and repair it.

"Our crews actually patrolled the line using helicopters, to see where the tree fell on the line", Hydro One spokesperson Richard Francella told Pure Country 96.7 on Tuesday morning.

"It's quite a vast area and it has quite a few remote pockets, so it took quite awhile for crews to access the site", Francella added.

In addition to waiting for firefighters to declare the area safe, power crews had other factors to consider.

"It's extremely high-voltage; you need clearance to go in and make those repairs.  The necessary equipment has to be brought in to the area as well.  So there's a lot that needs to be accounted for, before crews can actually go in and make those repairs", Francella said.

Extensive Outage

At one point more than 20,000 customers, both with Hydro One and Ottawa River Power, had no electricity.

Early Monday evening, Hydro One switched to other sources from the provincial grid to bring just over half of those customers back online.

However, more than 8,000 cusomters were without electricity all night.

By just before 7:00 a.m. on Tuesday, Hydro One said all of the cusomters who were affected by this outage were back online.

"Thank you for your continued patience while we work to restore power", said a post by Hydro One's official Twitter account.