New study shows huge groundwater losses along Colorado River

The Colorado River basin has lost huge volumes of groundwater over the past two decades, according to a new report from researchers at Arizona State University. Researchers used data from NASA satellites to map the rapidly-depleting resource.

The region, which includes seven Western states , has lost 27.8 million acre-feet of groundwater since 2003. That's roughly the volume of Lake Mead, the nation's largest reservoir.

The findings add a layer of complication for the already-stressed Colorado River. As demand for its water outpaces supply, more users may be turning to groundwater instead, which is often less regulated than water from above-ground rivers and streams.

The majority of water conservation work throughout the Colorado River basin has been focused on cutbacks