High Quality Content by WIKIPEDIA articles! The Don River is one of two rivers bounding the original settled area of Toronto, Ontario along the shore of Lake Ontario, the other being the Humber River to the west. The Don is formed from two rivers, the East and West Branches, that meet about 7 kilometres (4 mi) north of Lake Ontario while flowing southward into the lake. The area below the confluence is known as the lower Don, and the areas above as the upper Don. The Don is also joined at the confluence by a third major branch, Taylor-Massey Creek. The Toronto and Region Conservation Authority (TRCA) is responsible for managing the river and its surrounding watershed.