The Clark County Medical Examiner is assisting in determining the cause of death, the park service said. This is at least the third body found in the Lake Mead area as the nation’s largest reservoir has receded to unprecedented levels. The first body, discovered on May 1, was found in a barrel and was likely a homicide victim who died of a gunshot wound “sometime in the mid-70s to early 80s, based on clothing and footwear with which the victim was found,” according to a news release from the Las Vegas Metropolitan Police Department. Another set of remains was found May 7 in the Callville Bay area of the park. Receding waters have also exposed previously sunken boats, including a of a World War II-era landing craft last month Some 40 million people in the West rely on water from the Colorado River and its two largest reservoirs — Lake Mead and Lake Powell — where levels have dropped at an alarming rate in recent years amid a major drought fueled by climate change.On Tuesday, Lake Mead’s water level was at 1,040 feet, pe falling 174 feet below its level in 2000, when it was last considered full. It is the lowest level recorded for the reservoir since it was filled in the 1930s. The lake’s low water level exposed one of the reservoir’s original water intake valves in April for the first time. The valve has been in operation since 1971, but can no longer pump water, according to the Southern Nevada Water Authority. This agency is responsible for managing water resources for 2.2 million people in southern Nevada, including Las Vegas. “The lake has dried up dramatically over the last 15 years,” Las Vegas Metropolitan Police Department Homicide Lt. Ray Spencer said in May. “It is possible that we will find additional bodies dumped in Lake Mead” as the water level drops further. CNN’s Eric Levenson and Rachel Ramirez contributed to this report.