Regional Updates - Overview of C1W Basins

Canada 1 Water (C1W) proposed modelling all of continental Canada in an integrated fashion. To achieve the desired model resolutions and computational efficiencies, the country has been divided into six large basins that range in size from 1.7 to 2.3 million km2.  The geometry of the six basins and the natural surface water drainage boundaries is highlighted in Figure 1.

Within the continental basins, extension into the USA is limited to the watershed divides of the respective fourth order watersheds. Nevertheless, even at this scale the transboundary watersheds include approximately one million km2 of the USA. 

The six continental basins (Table 1) consist of aggregated watersheds that drain to common continental margin oceans.  Three of the watersheds are recognizable large watersheds with key rivers systems, the Mackenzie River, Nelson River, and the Atlantic, which includes the Great Lakes–St Lawrence River.

In future newsletter issues we will explore each watershed in more detail and highlight some of the unique data assembly, modelling and water resource challenges of each of the regions.

Table 1: Continental Basin Mesh Overview

Figure 1. Continental drainage basins outlined by thin black line. The six basins are named from west to east, Pacific, Mackenzie, Arctic, Nelson, Hudson and Atlantic.

Figure 2. Close-up of the Atlantic watershed that includes the Great Lakes–St Lawrence River watershed along with with Atlantic Canada. The region has three distinct geological domains, St Lawrence – Great Lakes lowlands, Canadian Shield, and Appalachians and 5 hydrogeological regions.