River Flow Directions from North America's Continental Divide

The Continental Divide of the Americas (Great Divide) runs north-south along the Rocky Mountains' crest. Precipitation on either side drains to opposite oceans:

1. Westward → Pacific Ocean

Rivers west of the Divide in the Rockies flow to the Pacific. Examples:

• Colorado River – Rockies (CO) → Gulf of California.
• Columbia River – Canadian Rockies → Pacific (WA/OR).
• Fraser River – BC Rockies → Strait of Georgia.
• Sacramento River – Cascades/Sierra → San Francisco Bay.

2. Eastward → Atlantic Ocean / Gulf of Mexico

Rivers east of the Divide flow to the Atlantic/Gulf. Examples:

• Mississippi River – Source in MN (not Rockies); tributaries (Missouri, Yellowstone) rise in Rockies → Gulf of Mexico.
• Rio Grande – Colorado Rockies → Gulf of Mexico.
• Platte, Arkansas, Red Rivers – Plains tributaries fed by Rockies snowmelt.

3. Northward → Arctic Ocean

In Canada, the Divide arcs across the northern Rockies. Rivers flow north:

• Mackenzie River – Rockies (Great Slave Lake) → Beaufort Sea (Arctic).
• Peace, Athabasca, Liard Rivers – Feed Mackenzie system.
• Yukon River – BC Coast Mountains → Bering Sea (Pacific/Arctic marginal).

Note: The Appalachians have a separate Eastern Continental Divide (Atlantic vs. Gulf drainage), not the primary Rocky Mountain Divide.