Duffins & Carruthers Creek Watersheds
The Duffins and Carruthers Creek watersheds lie to the east of Toronto and drain into the north shore of Lake Ontario. These two river systems connect communities across Durham Region and York Region including the City of Pickering, the Towns of Ajax, Markham and Whitchurch- Stouffville, and the Township of Uxbridge. They are among the healthiest of watersheds in the Greater Toronto Area.
The Carruthers Creek watershed is one of the smallest watersheds in the Greater Toronto Area, covering 38 square km. Rather than beginning on the Oak Ridges Moraine, its headwaters are found in the Halton Till. Its waters flow south across the sands and gravels of the Lake Iroquois shoreline, through the deep water silt and clay deposits of glacial Lake Iroquois, and out to Lake Ontario through the Carruthers Marsh.
The Duffins Creek watershed, on the other hand, covers some 283 square km. The Moraine provides abundant groundwater for its headwaters, where cold-water streams support brook trout, and large areas of forest and wetland form large natural habitat patches.
In the mid-reaches, the slope-till-plain includes both high quality valley land and several swampy forests. At the mouth of the creek is Duffins Marsh, one of the healthiest coastal marshes in the area, noteworthy for its wildlife and aquatic habitats.