Full subway service has been restored following severe flooding at Union Station on Friday afternoon.

The flooding began at around 12:30 p.m., requiring the immediate evacuation of Union Station and the suspension of service between Osgoode and Bloor stations.

The flooding was stopped hours ago but the damage was significant, Toronto Transit Commision CEO Andy Byford said.

About 100 shuttle buses were used during the afternoon rush to accommodate commuters.

"It still looks pretty bad. The water is all over the tracks and there is at least several hours of pumping left to do, and after that we will have to do all of our electrical testing," Byford told CP24 earlier Friday afternoon. "We have to test all of our escalators, all of the track and the switches. There is no way that we are going to put trains through if we are putting our customers at risk."

For a look at the mess, click here for a photo gallery.

According to Byford, some passengers were originally trapped on the platform at Union Station.

There was more than three feet of water inside Union Station at one point and firefighters had to carry some people out to safety.

"Our first priority was to make sure people were safe and the fire brigade did a fantastic job getting everyone out of the station and as a result nobody was hurt," Byford said.

Power was cut at Union Station as crews worked to fix the problem.

The flood was caused by a sewage backup and was a mix of water and sewage, Byford said.

"I was probably here at 12:45 p.m. or so and the stench was just overpowering. It really was bad," he said. "It's not just a question of mopping the water away. We have to sterilize the station. We can't put our passengers at risk of bacterial infections."

Front Street was also closed from Bay to York streets as a result of the flooding.

Ford inspects damage

Late Friday afternoon, Mayor Rob Ford visited Union Station to inspect the damage himself.

Speaking with reporters outside the station afterwards, he said he had offered Byford any "assistance and resources" he required.

"Whatever I can do to help get this problem rectified I will do and that's what I told him," he said.

Though the bowels of Union Station were in clear disarray Friday, Ford said the cleanup effort was progressing quickly.

"The cleaners are in there, they are sanitizing everything and they are doing a phenomenal job," he said. "When you see the stain of where the water was just a few hours ago and see where it is now, it's incredible."

Flooding reported nearby

In addition to the flooding at Union Station, water also rushed into the lobby of Royal Bank Plaza and the PATH system at the Union Station GO Terminal.

As a result of the flooding, the PATH system at the Union Station GO Terminal was closed at around 2 p.m.

GO Transit, however, continued to operate according to schedule.