Ontario Watershed Boundaries With Multi-Level Drainage Areas

2026 data from the Government of Ontario provides authoritative watershed boundaries for the province. It includes five data classes covering primary, secondary, tertiary, quaternary, and detailed 5th and 6th level watersheds. This collection replaces the historical Provincial Watersheds dataset.

Use Cases

• Delineate primary watersheds for large-scale hydrological modeling and regional water resource planning.
• Analyze land-use impacts on specific quaternary or 6th-level sub-drainage areas for localized conservation studies.
• Map pollution source and sink relationships across secondary and tertiary watershed hierarchies.
• Replace historical provincial watershed data in legacy systems with the updated OWB main class boundaries.

Strengths

• Adopts a stringent scientific approach to watershed delineation, improving on previous frameworks.
• Provides a hierarchical structure with five data classes, from primary to detailed 6th-level areas.

Limitations

• Specific quantitative metrics like total row count, spatial resolution, or file size are unavailable.
• Sample data and a detailed column schema are not provided, limiting immediate analysis readiness.

Provenance

Source

Government of Ontario, serving as the authoritative source for provincial watershed boundaries.

Collection Method

Delineated based on a framework similar to the Atlas of Canada and US Watershed Boundary Dataset, with enhanced scientific rigor.

Time Range

null

Freshness

Last updated in March 2026, indicating planned maintenance and current data.

Geography

Covers the province of Ontario, Canada.