Mattagami River


The Mattagami River is a river in Northern Ontario, Canada.
The Mattagami flows from its source at Mattagami Lake in geographic Gouin Township in the Unorganized North Part of Sudbury District, on the Canadian Shield southwest of Timmins, to Portage Island in geographic Gardiner Township in the Unorganized North Part of Cochrane District, in the Hudson Bay Lowlands. Here, the Mattagami's confluence with the Missinaibi River forms the Moose River, about from that river's tidewater outlet at James Bay. The Mattagami River flows through the city of Timmins as well as the town of Smooth Rock Falls and its drainage basin encompasses. It is close to tourism sites offering activities such as fishing, canoeing and nature-based relaxation.
The Mattagami's name comes from the Ojibwe and means either "the start of water" or "turbulent water", but the local Ojibwe population claim "Mattagami" is a corrupted form of "confluence". According to the Mattagami First Nation, Mattagami means "Meeting of the Waters".

Course

The Mattagami River flows generally north for approximately 443 kilometres. Its drainage area covers about 37,000 square kilometres. The river originates at Mattagami Lake in the Sudbury District, southwest of the city of Timmins, and lies on the Canadian Shield. The upper course incorporates Kenogamissi Lake, which is managed for downstream power generation. The Mattagami flows north through the city of Timmins, which relies on the river as a source of drinking water. Further north, it passes the town of Smooth Rock Falls. Much of the middle section of the river has been developed for hydroelectric power, consisting of a chain of long lakes and reservoirs created by stations such as the Kipling, Smoky Falls, and Little Long Generating Stations. The Mattagami continues its northward course, entering the flatter landscape of the Hudson Bay Lowlands. Its course officially ends at the confluence with the Missinaibi River near Portage Island in the Cochrane District. At this point, the two waterways combine to form the Moose River, which then flows northeast for approximately 100 kilometres before discharging into James Bay, an arm of Hudson Bay, near the communities of Moosonee and Moose Factory. Significant tributaries feeding the Mattagami include the Groundhog River, the Kapuskasing River, and the Tatachikapika River.

Economy

Where the Groundhog and Kapuskasing Rivers flow into the Mattagami, Ontario Power Generation operates the Little Long Generating Station, with a dam just over 5 km in length.

Tributaries

Tributaries include the:
  • Kapuskasing River
  • *Nemegosenda River
  • **Chapleau River
  • Groundhog River
  • *Ivanhoe River
  • *Nat River
  • Poplar Rapids River
  • Kamiskotia River
  • Grassy River
  • Tatachikapika River
  • Mattagami Lake
  • *Minisinakwa River
  • **Nabakwasi River
  • ***Opikinimika River
  • **Noble River