This is a subset of the larger single NHN Index file ("Index of available files") published on the Open Government of Canada Portal (open.canada.ca/en) for the Shape (ESRITM) format. This subset layer was created by a CanWIN staff. Pre-packaged shapefiles of individual watersheds can be downloaded from the Open Government of Canada Portal using the Dataset Name attribute to identify each watershed shapefile. 

The NHN Index is a national index that groups together all “NHN Work Unit Limits” at a specific time “T” for the entire Canadian landmass. This index is updated and published at interval on the GeoBase portal according to a “per release” approach, synchronized with NHN data publication. Update and publication frequency is determined according to NHN data publication. The NHN Index was first published March 20, 2008. Because it is generated at a specific time “T” and comprises all “NHN Work Unit Limits in the country, those limits are thus at different editing stages, where some have been fully edited and others partially or not at all. Moreover, it is important to realize that “NHN Work Unit Limits” will be modified over time, for example when new more up-to-date source data become available.

The NHN Index is distributed in SHAPE (ESRITM) format. This document thus provides its description for this format. In particular, it describes file names, features and attributes that make up the index.

• Cartography
• Coastline
• Drainage
• Earth Sciences
• GeoBase
• Geographic Information Systems
• Geographic data
• Geography
• Hydro
• Hydrographic Network
• Hydrography
• Hydrology
• Lakes
• NHN
• Natural resources
• Network
• Rivers
• Surface water
• Water
• Watercourses
• Watersheds

Open Government Licence - Canada (https://open.canada.ca/en/open-government-licence-canada)

The National Hydro Network (NHN) focuses on providing a quality geometric description and a set of basic attributes describing Canada's inland surface waters. It provides geospatial digital data compliant with the NHN Standard such as lakes, reservoirs, watercourses (rivers and streams), canals, islands, drainage linear network, toponyms or geographical names, constructions and obstacles related to surface waters, etc. The best available federal and provincial data are used for its production, which is done jointly by the federal and interested provincial and territorial partners. The NHN is created from existing data at the 1:50 000 scale or better. The NHN data have a great potential for analysis, cartographic representation and display and will serve as base data in many applications. The NHN Work Unit Limits were created based on Water Survey of Canada Sub-Sub-Drainage Area.

Source: https://open.canada.ca/data/en/dataset/a4b190fe-e090-4e6d-881e-b87956c07977