Water is the lifeblood of any bioregion. The Cascadia bioregion defines the Pacific Northwest of North America and is defined by the watersheds of the Columbia, Fraser, and Snake River valleys. These rivers give life to a region, and tell the story of this place. Depicted here for the first time, is the complete series of rivers that make up the hydrology of the Cascadia bioregion, not divided into the United States or Canada, but rather, one complete systems of interconnected streams, rivers and waterways.

Our Cascadia Hydrological Map shows in fascinating detail how our rivers and streams flow and interconnect, merge and diverge, carrying life to the land. Cascadia has long inspired generations of cartographers, geographers, planners and visionaries. The flow of water also has an inherent aesthetic elegance that our map captures beautifully.

It’s all in the details. Our map depicts every river in the bioregion—even intermittent streams—and every body of water with a diameter greater than 6 miles. For an extra dimension of depth, we apply a method called the Strahler Stream Order to show the hierarchy of streams as they flow from their source—rivers are shown thicker as they acquire the flow of tributaries. We think it enhances a sense of the interconnectedness of our waterways.