How Arizona can sustain such a large population?

?How Arizona can sustain such a large population?

We spent a few days in Tucson, Arizona. Tucson is extremely dry and hot. Santa Cruz River passes by Tucson. But the river is completely dry. How can such a dry place sustain more than half a million people? Furthermore, how can Phoenix metropolitan area sustain five million population?

The answer is the Central Arizona Project, an aqueduct system that transports water from Colorado River to the valleys of central Arizona. We may live in the modern era. But our basic needs remain the same, water and food. The difference is the modern society’s ability to transport water and food over long distance. 

But there are costs to other places. So much water is diverted to Arizona, California and other places. When Colorado River reaches Mexico, little water is left. The prosperity of US is paid by the desolation of Mexico. 

Santa Cruz River, the river passing through Tucson, used to have water. But water is pumped into agricultural land in the upstream. Now it is completely dry most of the time.