Although the rainfall has begun to taper off in Toronto, city officials are warning that there's still a flooding risk as the already saturated soil can no longer absorb more water. 

The rain that began Thursday afternoon continued to douse the city throughout Friday with up to 70 millimetres expected to fall by the end of Saturday.

The problem, however, is that the city has seen 47 per cent more rainfall in April compared to the monthly average, according to Environment Canada's historical data. In fact, more than 100 mm of precipitation fell since early April before the storm began Thursday. 

Mayor John Tory said the city was lucky that the storm wasn't as severe as predicted.

"Everybody has been working hard to make sure of course, first and foremost, that Torontonians remain safe, that our assets are protected and that people can keep moving across the city," he told reporters at 5 p.m. Friday.

"But the ground just can't absorb any more of that water."

Toronto island access restricted

The fallout from that has been most evident on the Toronto Islands. Residents there have been warned about a possible evacuation as Lake Ontario has risen through the sandbar and has bubbled up to flood lawns and roadways.

The mayor toured Ward's Island Friday, home to about 700 residents, many of whom had seen their lawns turn into ponds in the past few weeks. 

Residents and city staff have laid down more than 3,000 sandbags to prevent the rising waters of Lake Ontario from damaging properties, Tory said. While a few people reported flooding in their basements, the worst problem has been flooded roadways and lawns. 

The city has restricted access to the island to residents, staff and emergency personnel:

  • Regular ferry service to Centre Island and Hanlan's Point Docks is cancelled.
  • Ferry service to Ward's Island Dock will continue on the spring schedule with no changes (see the full schedule below).
  • If required, vehicles will be transported to Hanlan's Island Dock.
  • Also, due to flooding concerns, staff and students from the Island Public School have been relocated to Nelson Mandela Park Public School in Regent Park.

Swollen waterways

The city decided to keep the Don Valley Parkway open for the Friday afternoon commute, something Tory said was partly possible due to spring maintenance conducted several weeks ago, during which staff cleared out the catch basins. 

But there's the possibility of a closure later this weekend. 

Tory said that staff will keep an eye on rising water levels in that area — and in the other rivers and tributaries throughout the city.

The mayor asked people to "have the good sense to avoid those areas" if they're out walking on the weekend.

Where it's wettest

Here are the GTA rainfall totals as of 2 p.m. ET Friday:

Hamilton 52.6 mm
Welland 48.7 mm
Waterloo 36.5 mm
Downtown Toronto 43.9 mm
Oshawa 34.9 mm

Toronto - Don Valley Parkway

The city considered closing the DVP to traffic during evening rush hour, but made a last-minute call to keep the highway open. (Trevor Dunn/CBC)