While quite a few resources are essential for the maintenance of our civilization, water is unquestionably the most important. (While air is more essential, its entirely even and inexhaustible distribution across the world means it's somewhat less useful to consider it in the same way as other resources.) If you run out of water, your civilization dies. It's one of the few ironclad rules of history. And, delightfully enough, we're running out of water.
Actually, it'd be more accurate to say that we're overstressing the planet's freshwater supplies with industrial, municipal, and agricultural demands. The shifting weather patterns resulting from climate change and widespread deforestation are just exacerbating the problem. If we don't do something quickly to change the way our civilization thinks about and consumes its water, we're going to reach a breaking point quickly.
Let's zoom in from a global perspective to America in the 1960s. More specifically, the pilot for the original Star Trek, featuring Captain Pike. Pike's home on Earth is shown to be Mojave- the desert turned lush, fertile, and green, with a city of the same name resembling Oz's Emerald City in the center. While this seems like just science fiction, it comes out of very real and omnipresent predictions at the time- that we'd be able to harness the West's water and turn all of the American deserts green.
The Mojave desert turned into luxuriant parkland in Star Trek. [Image source]
Star Trek- and American society at the time- couldn't have been more wrong. Beginning in the late 1800s, we systematically dammed rivers across the continent, redirecting their flows to massive cities and agricultural projects built in the middle of inhospitable land. Today, the overwhelming majority of rivers in America have been dammed- we've constructed over 40,000 of the environmental nightmares. The rate of construction has slowed down- partially due to environmentalist opposition, but even more because we're largely out of good dam sites.
It's hard to overstate how ridiculous dam building fever. LA almost went to war (not a metaphor, actual armed combat with their police forces) against another city over water, eventually stealing all their water and killing the other city. The single leading cause of Jimmy Carter losing most of his political power during his presidency was his opposition to a huge number of pork barrel dam building projects. It resulted in numerous extinct species, flooded ecosystems, and has even resulted in environmental damage to the oceans. And now that fever has spread across the world- China is building dams at a rate perhaps even higher than our own was, and many other nations have joined in as well. Brazil is even trying to dam many tributaries of the Amazon river.
The Glen Canyon Dam, one of the greatest environmental atrocities in American history. [Image source]
Why exactly are dams so harmful? Well, apart from flooding ecosystems upstream of them, the large pools of standing water result in a massive increase in evaporated water, enough to seriously reduce the total amount of water in the river systems in question. Even more severely, dam building seems to almost always result in a local culture of copious water over-consumption- water resources tend to be even more stretched a few years after the dam was built than they were to start with. As soon as a drought comes along? The water dries up almost entirely.
Cape Town, one of the major cities of South Africa, is currently undergoing a massive water crisis- there's a high risk of it entirely running out of water, hitting 'Zero Day', within the next year. Residents are currently restricted to a mere 50 liters of water per person per day- which is not very much water at all. Schoolchildren often spend their entire days at school without water. The actual water shortage is caused by a three year drought, but Cape Town could have withstood the problem much better if it wasn't for chronic mismanagement of their water resources. Their dammed reservoirs should have been enough to keep them afloat otherwise.
Cape Town, South Africa's second largest city, is facing critical drought conditions. [Image source]
Back to the Midwest- at the same time as we began building dams, we also began tapping groundwater at an absurdly unsustainable rate. Though aquifers can hold a truly stunning amount of water, once that water is gone it can take thousands of years for them to refill. America's breadbasket, the Great Plains, lies atop the Ogallala aquifer, one of the greatest on the planet- and it's starting to empty out. There are areas of Western Kansas where the aquifer is completely dry, and many other places where the water level in the aquifer has dropped so low as to become cost prohibitive to pump.
This critical shortage in the Ogallala aquifer- and many other aquifers- is the result of typical economic shortsightedness. Why do you need more technologically demanding and labor intensive methods of farming that conserve water when you can just pump unlimited water from the ground? Well, for one, because it's not unlimited, but Midwestern farmers were, by and large, completely ignorant or ignoring that fact throughout much of the 20th century. It's a fairly classic tragedy of the commons scenario brought about by our perpetual willingness to bargain away long term sustainability for short term gain.
A map of water loss in the Ogallala Aquifer between 1980 and 1995. [Image source]
Loss of groundwater doesn't just harm regions by killing agriculture (and property values, and the ability to sell your house, or even having water in your house)- it can have much more immediate, severe effects. As you take water out of the ground, it results in subsidence- the ground actually sinking downwards. Sinkholes are becoming a much more frequent occurrence around the world, posing severe threats to property. More alarming than that is coastal subsidence, however.
Let's spin halfway around the globe to Jakarta, the capital of Indonesia. Jakarta is facing the twin threats of climate change related rising seas and land subsidence. So much groundwater is being tapped- both officially and by illegal wells- that the city is sinking rapidly. Even with heavy rains and numerous rivers, the concrete and asphalt that covers 97% of the city is keeping their aquifer from replenishing. 40% of the city now lies below sea level, protected only by haphazard and leaky seawalls.
A Jakartan slum. The city is rapidly sinking thanks to groundwater subsidence. [Image source]
Experts give Jakarta about a decade of life left before it's flooded unless they can stop the subsidence sinking the city. Given the endemic corruption and profiteering, that seems unlikely. The illegal wells certainly won't vanish until the city can guarantee its residents reliable water, which is unlikely to happen soon. Indonesia has planned an immense dike entirely enclosing Jakarta Bay to keep out the sea, but given the disgusting state of Jakarta's rivers and bay, it would turn Jakarta Bay into a giant cesspool- cesspool in a very literal and not metaphorical sense.
Jakarta is far from alone in dealing with coastal subsidence issues- much of the Bay Area, including Silicon Valley, faces the same problem. This is exacerbated by the fact that much of San Francisco and the Bay Area is built onto landfill extended into the sea. Hell, coastal cities around the world are facing these problems. In fact, many of the dreary predictions that climate change science has made about coastal flooding grossly underestimate the speed and impact of coastal subsidence on flooding. Since 40 percent of the world's population lives within 100 kilometers (62 miles) of the coast, this is clearly problematic.
Unless we critically rethink our water usage, we're going to start running out. Soon. International relations are already starting to reflect it. Spats and diplomatic incidents between nations over water are growing more and more frequently, especially when the source of one nation's water originates inside another nation. The area of the world we should be watching most carefully for water related conflict? Tibet. China, India, Nepal, Bhutan, Bangladesh, Pakistan, Vietnam, Myanmar/Burma, Cambodia, Laos and Thailand all depend on rivers that originate there. China's ownership of the Tibetan Plateau means they control the source of 46% of the world population's water. Nothing can go wrong with that, right?
- Cadillac Desert: The American West and Its Disappearing Water, by Marc Reisner