The Colorado River Water Crisis Demands Urgent Action

The Colorado River Basin has reached a water crisis after a drought lasting more than two decades and intensified by climate change threatened supplies for cities, farms, and ecosystems across the American Southwest.

Temperatures in the basin have risen faster than anywhere else in the lower 48 states, with some areas warming at more than double the global average, and the river's average flow has fallen nearly 20 percent since 2000, roughly half of that decline attributable to rising heat.

Scientists project that additional temperature increases of 2 to 5 degrees Fahrenheit by 2050 could reduce flows by another 10 to 40 percent, endangering more than 150 species that depend on the river ecosystem.

The federal government issued its first ever Tier 1 shortage declaration in August 2021, cutting allocations to Nevada, Arizona, and Mexico, and later called for 2 to 4 million acre feet in additional water savings for 2023.

The Nature Conservancy is pursuing solutions including voluntary water banks that compensate users for conservation, forest management to protect the watersheds that supply 90 percent of the basin's water, more efficient irrigation, and first of its kind agreements that let tribes lease water for environmental flows.

As one local rancher put it, the moment demands experimentation, warning that doing nothing is itself failure.