Standard Drainage Area Classification (SDAC) 2003

Status: This standard was approved as a departmental standard on February 16, 2009.

The Standard Drainage Area Classification (SDAC) is Statistics Canada's official classification of drainage areas in Canada. The SDAC provides unique numeric codes for the levels in the hierarchy of drainage areas: major drainage areas, sub-drainage areas and sub-sub-drainage areas. The three geographic areas are hierarchically related; a 4 character code is used to show this relationship. In addition to the drainage area classes, a classification variant of the sub-sub-drainage areas by drainage regions and ocean drainage areas is included. The relationship between these geographic areas is illustrated in the diagram showing the Standard Drainage Area Classification and the hierarchical structure of the classification.

The Standard Drainage Area Classification (SDAC) 2003 is based on Version 5 of the National Scale Frameworks Hydrology - Drainage Areas, Canada. The National Scale Frameworks Hydrology was developed by a partnership consisting of Natural Resources Canada, Environment Canada and Statistics Canada.

Note: Some drainage areas in the Frameworks dataset straddle the Canada-United States border; the Standard Drainage Area Classification (SDAC) 2003 includes only the parts within Canada since this is used for reporting Canadian data. The SDAC 2003 excludes 4 of the sub-sub-drainage areas that are entirely outside the boundary of Canada.

Classification structure