Ontario Watershed Boundaries

This collection represents the authoritative watershed boundaries for Ontario. The data is based on a framework similar to the Atlas of Canada Fundamental Drainage Areas and the United States Watershed Boundary Dataset, however it adopts a more stringent scientific approach to watershed delineation.

The Ontario Watershed Boundaries (OWB) collection includes five data classes:

  • OWB main: all levels from primary to quaternary and 5th and 6th levels in select areas
  • OWB primary: all primary watersheds or major drainage areas in the Canadian classification
  • OWB secondary: all secondary watersheds or sub drainage areas
  • OWB tertiary: all tertiary watersheds or sub sub drainage areas
  • OWB quaternary: all quaternary watersheds or 6-digit drainage areas.

The OWB data replaces the following data classes:

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Data Available

The data described here is available for you to use. [Learn more]
[See the licence for how you're allowed to use this data.]

2013-01-18 - 2020-06-04

Supporting Files

This dataset has no supporting files

Additional Info

Field Value
Geographic coverage Ontario
Geography Breakdown None
Source URL/Address
Author Email
Maintainer branch
Last Validated Date 2021-05-19
Update frequency As required
Access instructions