Humber River - Thanks to those who originally posted this on the Whitewater Wiki. The Humber River is a tributary to Lake Ontario on the west side of Toronto. During spring melt and after storm events there is a stretch of the river between Lawrence Avenue and Dundas Street that can be a fun paddle. Different features come it at different water levels. Dependent on levels, you can either do a short run of the river or chose a spot to park and play at.