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Geophysical Lake Ontario

Map of Lake Ontario

  • second smallest by volume
  • average depth 283 ft. (86m)
  • retention time = 6 years (a measure based on the volume of water in the lake and the mean rate of outflow)
  • urban industrial centers (Hamilton and Toronto) on the Canadian side
  • U.S. shore is less urbanized, not intensively farmed

Lake Ontario map from the National Oceanic and Atmospheric Administration