Hoover Dam's Lake Mead at historic low water level

These white marks serve as a shocking signal.

Lake Mead has sunk to its lowest ever level, underscoring the gravity of the extreme drought across the U.S. West.

The reservoir created by Hoover Dam is crucial to the water supply of 25 million people

including those in Los Angeles, San Diego, Phoenix, Tucson and Las Vegas.

Here are some facts about it.

{Hoover Dam reservoir: Explained}

The Hoover Dam reservoir is an engineering marvel that symbolized the American ascendance of the 20th century.

It was formed in the 1930s from the damming of the Colorado River at the Nevada-Arizona border.

As of June 9th, the lake surface has fallen to just over 1,000 feet (on screen 1,071 feet) above sea level

dipping below the previous record low in July 2016.

It has fallen 140 feet since 2000 -

that's nearly the height of the Statue of Liberty from torch to base,

exposing a bathtub ring of bleached-white embankments.

Bruce Nelson is the director of operations of Las Vegas Boat Harbor and Lake Mead Marina.

(SOUNDBITE) (English) BRUCE NELSON, DIRECTOR OF OPERATIONS LAS VEGAS BOAT HARBOR AND LAKE MEAD MARINA, SAYING:"Here at Lake Mead, we're experiencing obviously low, low water levels that we haven't experienced since the dam was built. It's been this level before but it's when the water was rising. We've been close to this level last like five or six years ago, but we're going to a new historic low."

The drought that has brought Lake Mead low has gripped the U.S. West.

Farmers are abandoning crops,

Nevada has introduced lawn watering restrictions in the Las Vegas area,

and the governor of Utah is literally asking people to pray for rain.

Firefighters are facing worsening conditions this summer,

after nearly 10,000 fires in California alone during the last wildfire season burned 4.2 million acres of land.

The Bureau of Reclamation, which manages water resources in the Western states, is likely to declare Lake Mead's most extreme shortage condition for the first time ever.

That would cut water supplies to Arizona, Nevada and Mexico, says the Bureau of Reclamation spokesperson Patti Aaron.

(SOUNDBITE) (English) PATTI AARON, SPOKESPERSON THE BUREAU OF RECLAMATION LOWER COLORADO REGION, SAYING:"Lake Mead and Hoover Dam serve about twenty-five million people in the lower basin. We have a decrease of about twenty five percent of our capacity in producing power because of the lower lake levels."

While droughts are a recurring natural hazard,

they've been made worse recently by an accumulation of extremely dry years for most of this century.

Scientists say human-influenced climate change has exacerbated the situation.