San Juan River

The San Juan River is a major tributary of the Colorado River in the Southwestern United States, providing the chief drainage for the Four Corners region of Colorado, New Mexico, Utah and Arizona. Originating as snowmelt in the San Juan Mountains of Colorado, it flows 383 miles through the deserts of northern New Mexico and southeastern Utah to join the Colorado River at Glen Canyon. The river drains a high, arid region of the Colorado Plateau and along its length it is often the only significant source of fresh water for many miles. The San Juan is also one of the muddiest rivers in North America, carrying an average of 25 million US tons of silt and sediment each year.
Historically, the San Juan formed the border between the territory of the Navajo in the south and the Ute in the north.

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