A massive drought-starved reservoir on the Colorado River has become so depleted that Las Vegas now is pumping water from deeper within Lake Mead where other states downstream don’t have access.

The Southern Nevada Water Authority announced this week that its Low Lake Level Pumping Station is operational, and released photos of the uppermost intake visible at 1,050 feet (320 meters) above sea level at the lake behind Hoover Dam.

“While this emphasizes the seriousness of the drought conditions, we have been preparing for this for more than a decade,” said Bronson Mack, water authority spokesman. The low-level intake allows Las Vegas “to maintain access to its primary water supply in Lake Mead, even if water levels continue to decline due to ongoing drought and climate change conditions,” he said.

The move to begin using what had been seen as an in-case-we-need-it hedge against taps running dry comes as water managers in several states that rely on the Colorado River take new steps to conserve water amid what has become perpetual drought.