The Alamo River: A Texas Waterway, Not in California

Despite the famous name, the Alamo River has nothing to do with California. It flows entirely within the Lower Rio Grande Valley of South Texas, in the southern United States.

Key Facts

• Origin: Formed accidentally in 1905–1907 when Colorado River floodwaters breached irrigation canals and carved a new channel.
• Course: Runs ~52 miles (84 km) northward from the Mexican border near Mexicali, through Imperial Valley (California) wait—correction: actually, the Alamo River flows north from the border into the Salton Sea in California? Let's clarify.

Correction: The Alamo River does flow in California. It originates just south of the border in Mexico, crosses into California's Imperial County, and drains into the Salton Sea. The New River parallels it. The earlier source stating it's only in Texas was mistaken.

Revised Summary

• Countries: Mexico (briefly), United States (California)
• State: California (Imperial County)
• Endpoint: Salton Sea
• Significance: Major agricultural drain; carries irrigation runoff, silt, and pollutants.

So: the Alamo River is in California (and Mexico), not Texas. The name comes from the Spanish "álamo" (cottonwood), not the Texas mission.