Toronto residents are being warned to be careful around rivers, streams and shorelines due in part to rain this week that could cause water levels to rise. The Toronto and Region Conservation Authority is urging the public to be cautious around all bodies of water because of changing water levels in rivers in the Greater Toronto Area. Toronto is expected to see rainfall amounts of 10 to 15 millimetres on Wednesday. That amount is on top of the drizzle that fell on Tuesday.