www.travel-university.org

Drainage

North America has a wonderful system of waterways.

Pacific Drainage. The Yukon, rising in the northwest of the Western Mountain System, though 2,000 miles long, is relatively unimportant, as it is frozen for eight months in the year and flows westward through an almost uninhibited district. Farther south are Skeena and the Fraser, whose valleys are followed by Trans Continental Railways; the Columbia (1,400 miles) and its tributary the Snake (1,000 miles); and the Colorado, whose famous canyon forms a barrier to communications, but whose waters, like those of the Columbia, have been dammed for irrigation and power.

Arctic and Hudson Bay Drainage: The Mackenze (2,500 miles) drains Lake Athabasca and the Great Slave and Great Beau Lakes. The Saskatchewan-Nelson (1,900 mile) is the chief river flowing into Hudson Bay; the Saskatchewan flows into Lake Winnipeg, the Nelson carries its drainage into the Bay of Hudson.

Atlantic Drainage: Chief of all North American rivers flowing into the Atlantic is the St. Lawrence, which, with the Great Lakes, forms a water-ways extending for 2,400 miles into the heart of the continent. Farther south relatively short rivers are important because their valleys form routes to the interior, and their estuaries provide harbors on which stand some of the chief American ports. Among these streams are the Hudson and its tributary the Mohawk the Delaware; and the Susquehanna, the Potomac, and the James River, all three flowing into Chesapeake Bay.

Gulf Drainage: The principal river flowing into the Gulf of Mexico is the Mississippi (2,500 miles), whose basin cover one third of the United State. At St. Louis it receives from the Rockies the Missouri (2,450 miles), whose chief tributaries are the Yellowstone, Platte, and Kansas. Below St. Louis the principal tributaries of the Mississippi are the Arkansas and Red River, whose sources are in the Rockies, and the Ohio, which rises in the Appalachian Plateau.

The Rio Grande (2,000 miles) is the only other large river flowing into the Gulf of Mexico.

Next: Climate North America