Traffic was heavily congested around the King West neighbourhood Tuesday afternoon after a streetcar derailed during the morning and much of the evening rush hour.

The newly-delivered low-floor streetcars derailed in the intersection of King Street West and Bathurst Street at around 9:30 a.m.  The new streetcar was pushing an older model that had become disabled when its front wheels came off their rails as it turned on to Bathurst Street, according to TTC spokesperson Brad Ross. Neither streetcar was in service at the time.

Shuttle buses were up and running along King Street for most of the day.

Ross later explained that debris stuck in the rails at the intersection was to blame.

"Unfortunately, debris clogged the track and caused the new streetcar to climb up and derail," Ross said. "We're having a challenge getting it back on the rails."

The location of the incident also posed a challenge for workers who struggled to get the streetcar back on the tracks. The streetcar was finally removed from the area at about 6 p.m. Tuesday.

"It's much more difficult with new streetcars to re-rail them," Ross said. "The location of this particular incident is proving to be a real challenge."

As a result, the 511 Bathurst streetcar diverted both ways via Exhibition Loop, Queens Quay, Spadina Avenue and Dundas Street.

The 504 King streetcar diverted eastbound at Roncesvalles Avenue, Howard Park Avenue, Dundas Street and Spadina Avenue.