History Mystery

Curiosity drew me downtown to learn about Yuma Crossing. Why have millions chosen this place to cross the Colorado River? The answer is that all traffic west was funneled here by harsh geography–mountains and canyons. A glance at the map will confirm that this is the only reasonable place to cross.


In 1848, Gold Rush traffic at the crossing became so heavy that ferry operations began. One busy entrepreneur made $60,000 in one year–millions in today’s dollars. A railroad bridge made the ferries obsolete in 1877.


To this very day, Yuma is the only feasible US crossing within 100 miles for both trains and cars.

I discovered something equally surprising about this historic point–an extraordinary engineering feat. Here, Yuma’s main canal flows under the Colorado River. Yuma’s water supply flows from Laguna Dam 15 miles upriver. Geological considerations put the canal on the wrong side of the river. To get the water across to the Yuma side, a reverse siphon was constructed in 1915, down 90 feet, across a thousand, and up the other side, where it flows via gravity into Mexico, gradually being used up in agriculture. None reaches the sea.