The Colorado River Water Crisis Demands Urgent Action
The Story
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.
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.
Why It Matters
The river's arithmetic has become law. Interior's August 21, 2026 record of decision cuts Arizona, California and Nevada by 1.25 million acre feet a year for 2027 and 2028, Arizona alone losing 760,000, and sets a Lake Powell floor of 3,510 feet, 20 feet above the turbine intakes, while the Upper Basin faces only voluntary conservation, per KUER. Nevada sued three days later, arguing the plan could strip more than 70 percent of its allocation from 2029 and that Interior never weighed the hit to a $180 billion economy; Arizona is weighing its own suit (Las Vegas Sun). The old rules expire in October, and the states must renegotiate before these two years run out in 2028.
Go Deeper
Read the original reporting at The Nature Conservancy.
Read Full Story at The Nature Conservancy →