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[narrator] Turn on a faucet and clean water rushes out,
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as much as we want, anytime we want.
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It's easy to forget that the quest for this
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has been one of the defining struggles of human history.
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Civilizations that harnessed water, thrived.
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The ones that failed... fell.
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Today, seven in ten people on Earth
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can count on having running water in their homes.
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[man] The water flows from the risers to connecting mains,
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and finally through service connections into each building on the street.
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[narrator] At least, so they think.
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Cape Town. It could become the first major city in the world
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to run out of water.
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Cape Town, South Africa, is inching closer now to Day Zero.
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Just 92 days away from having to shut off most water taps
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because of a severe drought.
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[narrator] Cape Town is the first major city in the world
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to plan to indefinitely shut off its water supply.
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Four million people would stop getting running water.
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They'd get water rations,
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and they'd need to line up at city water stations to get it.
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And it's not just Cape Town.
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São Paulo, Melbourne, Jakarta, London,
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Beijing, Istanbul, Tokyo, Bangalore,
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Barcelona and Mexico City
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will all face their own Day Zero in the next few decades,
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unless their water use radically changes.
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There are perceptions that it is there in bountiful amounts
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and everyone has access to it because you can turn a tap,
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and that's a big problem.
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[narrator] In fact, by 2040
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most of the world won't have enough water to meet demand year-round.
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We're facing a global water crisis and it's getting worse.
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We're at a real inflection point where, if we're not careful,
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we may actually get out ahead of our ability to manage it.
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[narrator] There's no substitute for water.
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Each of us will die in just a few days without it.
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How have we built a world
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where we don't have enough of its most valuable resource?
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And as this crisis grows,
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what will the new world look like?
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[man] Waterways, built by the people
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to free the land of the tyranny of nature.
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For some investors, what they see in this glass
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is liquid gold.
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Clean water. Now.
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[crowd chants]
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-[in Spanish] In defense of water. -[man 2] Water becomes a commodity.
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It takes on new value.
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People claim it, haul it, treasure it.
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[man 3] Dare we take our water supply for granted as we do the air we breathe?
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[narrator] Earth is the blue planet.
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There's no shortage of water. We have 326 million trillion gallons of it.
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Always have, always will.
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Water may freeze into ice or evaporate into air,
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but it doesn't leave our planet.
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If you sucked up all the water on Earth, it would fit into this sphere.
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But 97% of it is salty and 2% is trapped in ice at the poles,
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so all of humankind relies on just 1% of that water to survive.
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When people talk about running out of water,
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what they really mean is,
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do they have access to that very small percentage?
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[narrator] And the answer depends a lot on where you live.
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Kuwait is one of the poorest countries in terms of water per capita,
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and Canada, one of the richest, doesn't have twice as much
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or even ten times as much. It has 10,000 times as much.
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But it also matters where the water is.
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That 1% of Earth's water that we all rely on,
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most of it is underground and really difficult and expensive to get to,
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so humans have mostly settled close to surface water, like rivers and lakes.
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Around 90% of the world's population
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lives less than ten kilometers from a freshwater source.
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Hundreds of years ago, when the Aztecs settled on what is now Mexico City,
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they saw a giant lake.
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These are the last remnants of the canals they made.
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When the Spanish came in the 16th century,
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one soldier marveled at the Aztec city rising from the water
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that seemed like an enchanted vision.
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But then the Spanish started draining the lake,
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and over the next few centuries that space was filled by people.
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Like in most places, surface water in Mexico
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was treated as a public resource, key to development.
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And since 1950, Mexico City's population has exploded.
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It's now home to 22 million people.
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I would say some of the most important threats
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for Mexico City are related to water.
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[narrator] Mexico City gets more rain than notoriously rainy London.
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But the lakes that would have collected that water are long gone,
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so the city floods.
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But they still need to pipe in
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most of their water from other parts of Mexico.
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Or they pump it from underground.
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We've gotten a lot better at accessing groundwater.
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But there's a catch.
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Those water deposits, called aquifers, have accumulated over millennia
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and they'll take millennia to fill back up.
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Groundwater is sort of like the savings account,
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which it's fine to draw on sometimes, especially when you have a drought.
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[narrator] That's not what Mexico City's been doing.
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We take out from the local aquifer around 50% of our water supply.
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That means that probably we'll lose half of our supply of water
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in the next 30-50 years.
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[narrator] Sucking up that groundwater has another side effect.
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It compresses the soil.
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Mexico City is literally sinking.
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In some places, as much as nine inches a year.
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NASA satellite data shows aquifers in northern India
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decreasing by 29 trillion gallons in just a decade.
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There are simply more people on Earth consuming more water.
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This century, water consumption has increased sevenfold.
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And the rain and snow that we count on to water crops and refill lakes and rivers
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is getting less reliable.
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[Otto] Climate change is making available water much more erratic.
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We're seeing areas around the world
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that are experiencing much more extended dry periods.
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[narrator] But the problem isn't just that there's more people on Earth using water,
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it's how we're using water.
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Humans need to drink almost a gallon of water per day.
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Brushing your teeth, washing your hands typically uses about a gallon.
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[flushes]
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There goes three gallons.
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But the drinking, washing and toilet flushing
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of every person on Earth only accounts for 8% of our freshwater use each year.
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Most of the water goes to agriculture and industry,
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and into the food and products we use.
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Let's take a bottle of Coca-Cola.
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98% of the water in that bottle
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is not what you see in that bottle.
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98% of the water is actually embedded in all the ingredients that were grown
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to make that bottle of Coca-Cola.
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[narrator] 74 liters of water goes into every glass of beer.
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A cup of coffee? 130 liters.
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Each of your cotton shirts - 2,500 liters.
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But nothing has as much embedded water as meat.
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Alfalfa is a common ingredient in cattle feed,
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and growing a kilogram of it takes 510 liters of water.
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An average cow consumes about 12 kilograms of feed a day.
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Divided up,
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just one quarter-pound hamburger takes around 1,650 liters of water to produce.
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The world is eating more and more like Americans.
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Higher calorie diets with more meat.
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But everyone can't eat like Americans.
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There actually isn't enough water in the world.
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Water doesn't abide by some of the basic rules of capitalism.
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Farmers hardly pay anything for it.
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So the true cost of water doesn't end up in the cost of the burger.
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Which is why those fast food places can offer you bargain burgers.
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[man 1] How can it be 99 cents?
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[man 2] For only 2.99. You heard right: 2.99.
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[narrator] In most places in the world,
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water is treated and priced like there will always be enough of it.
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So we end up using it in absurdly wasteful ways.
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Arid Southern California uses over two trillion gallons of water a year
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to grow alfalfa, which they get from the Colorado River,
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hundreds of miles away.
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The amount they pay for it doesn't even cover the cost of delivery.
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Just a fraction of the water used by South Africa's wine industry
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would be enough for Cape Town's taps.
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India and China both grow their most water-intensive crops
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in some of their driest regions.
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But as water gets more scarce, that may change.
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The bank Goldman Sachs predicted that water would be
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the petroleum of the 21st century.
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And private interests, like hedge funds, have started buying up water,
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prompting fears that they'll take advantage of scarcity to turn a profit.
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And if that sounds like a villain's plot in a James Bond movie,
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that's because it was.
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As of this moment,
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my organization owns more than 60% of Bolivia's water supply.
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This contract states that your new government...
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will use us as utilities provider.
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[narrator] But putting a higher price on water might have benefits.
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The benefit of valuing water as we should
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and sending, you know, a price signal,
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is that we wouldn't be growing alfalfa in the desert.
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[narrator] Remember that point. It'll be important later.
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We wouldn't be growing crops that don't make sense in really arid places.
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Because the economics of it wouldn't make sense.
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[narrator] And 95% of the irrigated farmland in the world
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probably wouldn't use the most inefficient irrigation method...
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just flooding the fields.
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And if water had a higher price,
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governments might decide it's worth the money
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to repair our water infrastructure.
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[Kramer] We are not investing the financial resources needed
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to make a good maintenance of the system.
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One critical result of this is that we have 42% of leakages
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in the water network.
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[narrator] Mexico City, which is facing an existential water crisis,
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loses close to half of its drinking water to leaky pipes.
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We value water so little,
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we dump two million tons
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of sewage and agricultural and industrial waste into it every day.
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There's no sense of value
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to what is really an incredibly invaluable resource in water.
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But then when we run out, we find what the cost of water truly is.
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[yelling]
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[speaking Spanish]
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[narrator] In 2017,
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the city of Mexicali finalized a deal with Constellation Brands,
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the maker of Modelo and Corona beers,
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to construct a brewery.
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It would be the biggest investment the region had seen in years,
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creating 750 permanent jobs.
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And, in exchange, the brewery was guaranteed a lot of water.
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But Mexicali doesn't have a lot of water to spare.
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Its main water source is the Colorado River,
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which starts in Colorado, in the U.S.
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Fed by melting snow in the Rocky Mountains,
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warmer temperatures in recent years have meant less snow,
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which means less river.
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You can tell how much less by that big bathtub ring.
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The river flows south, quenching a few American cities along the way,
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like Denver, Salt Lake City,
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Las Vegas, Phoenix and Los Angeles.
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Oh, and almost six million acres of farmland.
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By the time the Colorado River reaches Mexicali,
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it looks like this.
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[man, in Spanish] It's been a long time since we've had enough water.
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If the brewery settles in and starts producing,
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in a few years, we'll run out of underground water.
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[in Spanish] The farmers are the ones who get the worst of it.
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[in Spanish] They need 20 million cubic meters per year.
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If we compare that to, say, cities such as Ensenada,
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which need nine million cubic meters, it's more than double.
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More than double of a city.
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[narrator] The more scarce water gets, more access to it becomes a competition,
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with winners and losers,
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often with governments picking.
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In July 2018,
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the federal government of Mexico issued a decree
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making it easier for businesses like Constellation Brands
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to extract surface water all around the country.
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[in Spanish] We see this as a stick-up.
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It's also a warning
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not only for the Mexican people but the entire world.
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We know that many other parts of the world
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are fighting against these privatization projects
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that line the companies' pockets.
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[narrator] In January 2018,
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protesters tried to physically block the construction
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of the brewery's aqueduct.
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[in Spanish] The entire group of policemen came through that road in the front.
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They came here with their protective shields, in a single file.
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She's the lady that shows up in the video holding a pipe.
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[in Spanish] But we have to defend our water.
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Because it's a vital liquid.