The TTC 134 Progress route is being diverted in both directions to avoid the area.
Another water main break is causing traffic problems on eastbound Eglinton Avenue at Kennedy Road.
On Wednesday, at least a dozen of breakages were reported across the city, with some North York homes on Old Orchard Grove flooded with sewage water.
The relatively warmer temperatures are likely the cause of the sudden spat of burst water mains.
The city says North York, Scarborough and Etobicoke have a higher rate of water main breaks because pipes in those areas are predominately in clay soil instead of sand.
High Park sinkhole
Near High Park on residential Coe Hill Drive, crews began working with jackhammers early this morning to widen a two-metre wide and three-metre deep sinkhole that opened up last night.
The sinkhole started with a water main break, police said, and the sewers beneath the hole have collapsed.
Residents in the area told CBC News that the stretch of road had been seemingly unstable for several years.
The TTC 71 Runnymede route is diverting around the sinkhole.
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