About 40 million people depend on the Colorado River for drinking water, and it irrigates more than 5 million acres of farmland.
But a decadeslong drought along the river has depleted water levels in reservoirs Lake Mead and Lake Powell to record lows.
Dwindling snowpack in the headwaters and ever-increasing demand from agriculture and municipalities have overtaxed it to a near breaking point.
After years of negotiations, the seven basin states — Wyoming, Utah, Colorado, New Mexico, Nevada, Arizona and California — could not reach consensus this summer on a long-term management plan to replace the expiring regulatory framework that has governed the river for the last two decades.
What happens now?
Join PBS News science correspondent Miles O'Brien as he talks about the future of this critical waterway with scientists, policymakers and other stakeholders in a live event, "Tipping Point: A River Reimagined."