California's drought is 'a harbinger of the coming global water crisis'

The four-year California drought is causing unparalleled devastation to the region.

Analysts at Bank of America Merrill Lynch thinks it's going to get a lot worse.

"We view the unprecedented drought in California as a harbinger of the coming global water crisis," BAML strategists wrote in a note to clients on Tuesday.

"By 2050E, 45% of projected GDP is at risk, with as many as 50 countries at risk of conflict over water."

The numbers are scary. Groundwater levels have dropped as much as 100 feet, while the Sierra Nevada snow-pack is at only 5% of historical levels.

When considering the economic impact of the drought, it gets even more frightening.

"The drought is expected to cost California agriculture alone US $2.7 billion in economic costs in 2015, with disruption extending to mandatory water restrictions, wildlife, land subsidence, seawater intrusion, wildfires, and human health," the note said

BAML went on to estimate that California's water supply will be more than 13 trillion gallons short of demand by 2060, "with an 80% chance of multi-decade 'mega-drought' this century."

Just look at this chart to see how serious the situation is already becoming:

And water shortage is not an issue exclusive to the United States.

In fact, BAML reiterates from a report they put out in April that water scarcity is considered "the #1 global risk for 2015 in terms of impacts to economies, environments and people."

"Globally, 750 million people lack access to safe drinking water source and 2.4 billion have no access to proper sanitation facilities," the analysts wrote. "Close to 50 countries are officially classified as being water stressed, and up to 70% of the world's underground aquifers have reached peak water. Global water demand is set to overshoot supply by 40% by 2030E, and by 2050E, 3.9 billion people will be living under "severe" water stress."