Authorities in Las Vegas say a barrel containing human remains was discovered in Lake Mead, and more could turn up amid a drought that has dropped the lake’s water level to historic lows. 

The barrel was discovered Sunday afternoon by boaters who alerted the National Park Service. The agency said in a statement that rangers searched an area near Hemenway Harbor and found the barrel with skeletal remains. They are working with Las Vegas police.

The Clark County coroner’s office will determine the person’s identity.

Las Vegas police told 8 News Now the person probably was killed in the 1980s based on items found in the barrel, though authorities did not elaborate. Lt. Ray Spencer told the CBS affiliate more bodies are expected  to be discovered as the lake, which is east of Las Vegas and borders Nevada and Arizona, recedes. 

“It’s going to be a very difficult case,” Spencer told the outlet. “I would say there is a very good chance as the water level drops that we are going to find additional human remains.”

Spencer said investigators are examining growth on the barrel in hopes of tracing when it was placed in the lake and started to erode. 

‘Problems everywhere’:Water so low in massive reservoir that an intake valve is now exposed

West’s drought has no end in sight:‘If we do nothing, it’s going to be really bad’

Shawna Hollister told KLAS-TV in Las Vegas that she and her husband were docking their boat when they heard a woman scream. They then saw the body, which had a shirt and belt visible. The barrel appeared partially lodged in the mud. 

The barrel might have been visible because of Lake Mead’s low water level amid a historic drought.

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 low water levels also recently caused an intake valve to be exposed in Lake Mead, a troubling discovery that threatens water transportation and processing.

Water from Lake Mead drains into valves toward the bottom of the lake. The intake valves help send the water to water treatment plants, where it is processed into drinking water. 

Water levels at Lake Mead, located in Arizona and Nevada, have dropped to elevation 1,055 feet, the lowest since 1937, a year after Hoover Dam created the reservoir. 

Lake Mead and Lake Powell upstream are the largest human-made reservoirs in the U.S., part of a system that provides water to more than 40 million people, tribes, agriculture and industry in Arizona, California, Colorado, Nevada, New Mexico, Utah, Wyoming and across the southern border in Mexico.

Water levels at Lake Powell, too, have hit historic lows, falling below a mark set by federal officials to ensure power production and enough water to supply Lake Mead and other Colorado River users downstream. Both lakes were full in 2000, but they now are roughly 30% full.