The head of the union representing OC Transpo drivers is warning its members to take care when operating the city's new double-decker buses in windy conditions.

Amalgamated Transit Union president Craig Watson gave the warning after one of the double-decker busesĀ toppled over on Woodroffe Avenue Friday morning.

One double-decker bus flipped onto its side and into the ditch along Woodroffe Avenue near Fallowfield Road at about 7:30 a.m.

The driver, who was the only person on the bus, managed to crawl out safely through a window.

Watson spoke with the driver shortly after the incident.

Differing interpretations of what caused crash

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This double-decker bus flipped onto its side and into the ditch along Woodroffe Avenue near Fallowfield Road. (CBC)

"The wind blew him over... [to] where the plow had left its residue and so on, and then the bus started to hydroplane," said Watson. He said the driver then described losing control of the bus and toppling "in slow motion" into the ditch.

Watson says OC Transpo boss John Manconi called him soon after the incident with the same account.

"We're definitely going to have to make the drivers aware that this can occur, and that the passengers are aware, they might be a little bit later, but you'll be there safer, that's what's going to have to happen, we're going to slow it down a bit in these windy areas," said Watson.

In a statement about the incident, OC Transpo's manager of fleet maintenance James Greer mentions only road conditions, not wind.

"The double-decker bus was travelling on Woodroffe Ave between runs with no passengers when road conditions caused the bus to slide into the ditch. These conditions are considered regular road hazards related to the weather conditions," read the statement.

Greer also points out there were 29 other double deckers out on the roads Friday morning, and said they performed "extremely well" despite messy roads.