Lake Mead has just set a new all-time low — and that’s terrible news for the 20 million people in Nevada, Arizona and California who rely on it as a water source.

Lake Mead’s water level has reached an elevation of 1,074 feet, and it is likely to descend even from there, perhaps by as much as another 5 feet when June is all said and done, according to an ABC News report.

Fortunately, the water level should returned to 1,078 feet by the end of the year, but it still marks a dramatic new low in the continuing drought crisis on the Pacific Coast.

The drought has been going on for 16 years in the Colorado River Basin, and it is the worst in the 100-year recorded history of the area’s water levels.

The drop in water levels below 1,075 feet resulted in the triggering of a water reduction plan. Under the Colorado River System Conservation Program, the lower basin states will be trying to conserve 1.5 to 3 million acre feet of water in the coming years.

Lake Mead is the United States’ largest reservoir, located on the Colorado River just 24 miles from the Las Vegas Strip. The lake is formed by the Hoover Dam. It is 112 miles long when full, and has 759 miles of shoreline.

It has been more than 30 years since the lake was last at full capacity back in 1983 due to the ongoing drought and higher water demands from the surrounding area. The water it provides is vital not just to residents, but also to farmland.