Part 3/12:
Phoenix is situated in the Sonoran Desert—a region characterized by high sunshine, low rainfall, and infrequent, intense monsoon rains. Most of the rainfall evaporates under the desert sun, with less than 3% contributing to runoff. The desert's water resources stem from several sources:
Mountain Snowmelt: Prominent ranges like the Sierra Madre and the Rockies feed the Gila and Salt rivers via snowpack melt, providing longstanding water supplies.
River Diversions: The Colorado River supplies about 36% of Arizona's water, while local rivers (Gila, Salt, Verde) contribute additional flows.