The Colorado is America's most endangered river, according to a report from American Rivers that blames outdated-water management policies for putting the river at a critical crossroads.
Because of increasing water demands and climate change, said Matt Niemerski, the group's director of western water policy, the river usually dries up before it reaches the sea.
"We're in our 12th or 13th year of prolonged drought in the basin," he said. "We've had below-average precipitation most years, and that is compounded upon itself, year to year."
The Merced River in the Central Valley received special mention in the report because of proposed intentional flooding of a Wild and Scenic River:
The Wild and Scenic Merced River is a special destination for paddlers, anglers, and hikers, and is home to a variety of fish and wildlife, including a rare salamander. These outstanding values are threatened by a proposal to raise the New Exchequer Dam, which would flood a stretch of river and wildlife habitat.
The Colorado River provides drinking water to 36 million people from Denver to Los Angeles, according to the report. Niemerski said the focus needs to be on keeping more water in the river instead of taking it out.
"The most cost-effective way to do this is through conservation and efficiency measures," he said, "not necessarily the 'old' way of doing things, of building more dams and reservoirs, building large diversion projects that continue to take water out of the river system."
Scientists predict the Colorado River flows will be reduced by as much as 30 percent by 2050 because of climate change.
Aside from California, the river and its tributaries flow through a half-dozen other states and generate 250,000 jobs from outdoor recreation alone.
The report is online at americanrivers.org.