Sometime around the year 1300, the last of the cliff villages around what is now Mesa Verde were abandoned. The Ancestral Pueblo Indians, who constructed these beautiful and enigmatic homes high above the valley floors, had been living in the area for at least 600 years, building fantastic structures like those at at Aztec Ruins and Chaco Canyon in New Mexico. Chaco seems to have been one of the centers of an expansive state with outposts that ran from Mexico to Colorado. Experts at growing crops and managing water in a semi-arid environment, the Pueblo people exploded across the region, building homes, religious centers, storehouses, and work spaces. Despite living in the dry side of a mountain range, they managed to produce large crops of corn, beans, and squash to feed their growing population. 

However, the dates of some of their greatest structures came just before the whole region sharply depopulated and the complex Chaco culture collapsed. The primary reason for this collapse appears to be a severe and lasting drought that so reduced rainfall in the region that even the most careful water management could not sustain even a fraction of the population. 

Across time and around the world, drought has felled civilizations again and again. The very first large empire—that of the Sumerians and Akkadians—appears to have gone down primarily from drought. These people, who for three thousand years had maintained a complex set of canals and reservoirs that allowed them to turn barren ground into the breadbasket of the ancient world, could only watch in horror as year by year, decade over decade, a sustained drought made their great cities uninhabitable.  

Time and again, people have proved that irrigation and water management could build a paradise on lands that would otherwise be arid wastes. Time and again, a prolonged downturn in rainfall has demonstrated that even the best water management can’t help if there is no water to manage. Cities built in dry areas can be destroyed by drought. Whole cultures can fall.

That’s just as true now as it was when the last of the Ancestral Pueblo packed up their things and reluctantly walked away from Chaco.

July 1 map from U.S. Drought Monitor

When we think about the seemingly endless war in Syria, those thoughts tend to be centered on the mendacity of Bashir Assad and the maneuvering of various powerful countries, including Russia, which has long treated Syria as a client state. However, the civil war that began in 2011, which has generated over 11 million refugees and displaced people, was sparked to a significant degree by a prolonged drought leading to massive crop failures, economic disruption, and widespread hunger.

As a paper in the Journal of the American Meteorological Society recorded in 2014, “challenges associated with climate variability and change and the availability and use of freshwater” were a key factor in Syrian unrest. Just as in many regions, water “ownership” in Syria was subject to a whole series of legal agreements, traditions, and regulations. The long-term scarcity of water in the region made the importance of water access immediately obvious and a central part of many regional agreements. Those agreements fell apart as Syria was confronted by the worst drought in 500 years. The shortage of water is certainly not the only factor that led to Syria’s civil war, but it was just as certainly one of the major factors.

In a very real sense, the 11+ million people displaced in Syria aren’t war refugees: They’re climate refugees. And those refugees were displaced not by a change in the climate driven by the eruption of a super volcano, or the long-term fluctuations due to the planet’s ever changing axial tilt. The drought in Syria is almost certainly the direct result of the human-caused climate crisis.

When thinking about climate refugees, there’s a tendency to worry about the millions in Miami or New Orleans or other coastal cities who could be displaced by rising seas. That’s a legitimate concern, and one that gets closer to reality every year.

But there’s another group already facing a massive threat—cities in the Western United States that cannot exist without extensive water management and which cannot continue to exist at current rainfall levels. It’s not necessary to watch Chinatown to understand the importance of water management to cities from L.A. to Las Vegas. Mark Twain may never have actually said, “Whiskey is for drinking; water is for fighting over,” but the sentiment behind that statement shows that the people who built the cities, towns, farms, and factories of the Western U.S. well understood the critical importance of water access.

There’s a reason that domestic terrorist Ammon Bundy is currently threatening to throw open the flood gates at Klamath Falls in Oregon. It’s not because Bundy gives a damn about farmers in the region, or because he has some perverse hatred of the region’s endangered fish. It’s because Bundy understands that water rights always generate a high level of anxiety, and in the midst of a record-shattering mega-drought, those fears can be exploited.

Bundy won’t be the last to put his finger on this hot button. Water in the Western United States isn’t some hard-to-understand climate model, or some prediction that starts with the words “by the end of this century.” This is a disaster that is immediately visible in the form of dry river beds and empty reservoirs. It’s happening now.

It took almost a decade for representatives from Arizona, California, Colorado, Nevada, New Mexico, Utah, Wyoming, and the federal government to work out an agreement on just one part of how to dole out the diminishing supply of water. As a result of this and other agreements, some cities in the desert, such as Phoenix, are semi-secure for the immediate future. Others, like El Paso, Texas, which sits in the Chihuahuan Desert and sees less than nine inches of rainfall in a good year, have futures that are much less certain.

The ‘bathtub ring’ shows the massive drop in water levels at Lake Mead

The record heat that has plagued the West this year has gained the most attention in the news, and it’s hard to ignore temperatures that are killing dozens while triggering an early start to severe wildfire season. But the current heat dome is ultimately much less destructive than the severe drought that’s gone on for two decades.

It’s that length that’s the real concern. There are a number of cities in the U.S. that are so dependent on surface waters, and so lacking in storage, that even a short-term drought can generate severe problems (looking at you, Atlanta). But what’s happening in the West isn’t a blip. It’s a long-term trend that suggests that the warming planet created by the human-caused climate crisis is one in which this region is going to see significantly reduced rainfall. This is a situation that is likely to worsen, in a way that generates a large amount of impact, before it gets better—no matter what steps we take to remediate the climate crisis.

That impact is measured in far more than just turning off fountains, giving up watered lawns, and possible threats to a completely irrigation-dependent agriculture. As KLAS in Las Vegas reported on Tuesday, water levels at Hoover Dam have now dropped to the point where the ability to generate electricity is threatened. One-half of the electricity from the site goes to California, so when there are brownouts or shortages in the upcoming weeks, it’s not just the ongoing heat wave—it’s also the reduced supply due to the drought. By August, Lake Mead could be producing no electricity at all, as it hits levels that trigger automatic cuts in water usage.

Former marina at Lake Folsom, CA

California may be hit worse than most, specifically because it has both high population and a heavily water-dependent industry in the form of agriculture. The state’s diminished snow pack has generated only 20% of the anticipated runoff as high temperatures and dry creek beds have led that much-needed water to simply evaporate before it ever reached local rivers. 

Three-fourths of California has already reached the extreme drought designation. Drought levels in 2021 are poised to punch right through the levels seen the last time the state reached these conditions between 2012 and 2015. Those years were the four driest since the state began keeping records—emphasis on “were,” because that record looks to be eclipsed by the current drought cycle. The state is scarce on rainfall, short of snowpack, and reservoirs are at record lows. There are no good signs. Snowpack in the Sierra Nevada is now running at 5% of average for this time of year, even as rainfall is below half of average. 

The word for this is: unsustainable.

California has always been subject to periodic drought—water was always for fighting—but since the 1980s the cycles of drought have been coming harder and faster. What is still being labeled as “exceptional drought” is becoming less exceptional every day. This level of dryness could easily be the new normal, or even the baseline for even more powerful and sustained droughts ahead.

So … what happens now? Back in April, the USDA declared a drought disaster. That allows farmers to get low interest loans to help tide them over through the drought. But those are loans, not grants. They’re made on the assumption that next year, farmers will have the money—meaning the water—necessary to pay back those loans. There is absolutely no indication that this will be the case. The precipitation levels in 2021 are severe, but this is only the second year of the current extreme drought cycle. The last such sequence ended in 2017 after a run of over five years.

The severe drought in the West doesn’t look like a weather phenomenon: It looks like climate change. Treating it with patches designed to last through the short term is … very much what they did in Syria, and in Chaco, and in Sumer. Failing to plan for what’s happening by treating it as a long-term national crisis demanding an extreme urgency invites people like Bundy, and GOP Leader Mitch McConnell, to turn the crisis into a political opportunity at the cost of increased misery.