Ontario Provincial Hydrology Data For Watershed Generation

Ontario Integrated Hydrology data provides four key geospatial layers for provincial-scale hydrology applications: an Enhanced Watercourse stream network, a hydrology-enforced DEM, an Enhanced Flow Direction grid, and a StreamGrid raster. The Government of Ontario maintains this dataset, which is complete for the entire province for the first time, enabling watershed creation for any location. Data was last updated in March 2026.

Use Cases

• Generate watershed boundaries for any point in Ontario using the Enhanced Flow Direction (EFDIR) grid and hydrology-enforced DEM.
• Model surface water flow and runoff patterns by analyzing the StreamGrid raster and Enhanced Watercourse vector network.
• Conduct watercourse network analysis for regional planning using the geometry and attributes of the Enhanced Watercourse layer.

Strengths

• Complete provincial coverage for the first time, enabling watershed creation for any location in Ontario.
• Integrates four harmonized datasets: Enhanced Watercourse, enforced DEM, Enhanced Flow Direction, and StreamGrid.

Limitations

• Data for the Rainy River Basin on the US side is a static snapshot from the 2014 National Hydrography Dataset and may be outdated.
• Specific exceptions exist for points along international borders and the Ottawa River draining from Quebec, limiting full cross-border continuity.

Provenance

Source

Government of Ontario, harmonized with US National Hydrography Dataset for cross-border regions.

Collection Method

Generated from provincial hydrography and elevation data; US data is a harmonized snapshot.

Freshness

Updated after completion of major updates to source data like the Ontario Hydro Network or Provincial DEM; last platform update was March 2026.

Geography

Province of Ontario, Canada, with integrated data for the cross-border Rainy River Basin.