♪ ♪ ("Koyaanisqatsi" by Courtney Hartman playing) ♪ Your breath is burning my skin ♪ ♪ Your mouth ♪ ♪ Takes in my water ♪ ♪ And the clouds roll like a river ♪ ♪ The rain falls sharp as ice ♪ ♪ And the oceans tumble over ♪ ♪ Like mist in the night ♪ ♪ And my heart is a machine ♪ ♪ A machine keeping time ♪ ♪ And my body is a building ♪ ♪ Scraping at the sky ♪ ♪ And water looks like water running ♪ ♪ ♪ ♪ Water looks like water running ♪ Funding is provided by The Arthur Vining Davis Foundations, Lynn Bay Dayton and Bruce C. Dayton, Anne Ray Foundation, and viewers like you.

Thank you.

♪ ♪ (water rushing) KELLY McEVERS: Sometimes the best story is right there in front of you, but you don't see it.

How did I not see water?

(water rushing) I'm Kelly McEvers and I'm a radio journalist.

Every morning, I take a shower, I drink my coffee, but it never really occurred to me.

I now believe this humble molecule-- the one that's hitting my face every morning-- could be the most important untold story of our time.

So, with a team of filmmakers and scientists, this is our podcast-style documentary on the story of water.

It's easy to follow this story through a record-breaking drought.

Or in the increasingly frequent mega-floods.

But sometimes the connections to water are less obvious.

Like when dry forests burst into flames.

Or when water shortages wreak havoc on stock markets.

(crowd yelling) Without water, we struggle to feed ourselves, and people get desperate.

(crowd shouting) (firing) Changes to the supplies of water on Earth are shaping a new world order around us.

So, I have a new saying.

"If you want to understand why our world is changing, follow the water."

♪ ♪ ♪ ♪ So, what does a water crisis even look like?

Does it look like war?

Does it look like a famine?

Or does a water crisis hide in plain sight?

♪ ♪ Just 25 miles long and five miles wide, Gaza is near the epicenter of Middle Eastern conflicts.

(car horns honking) But instead of politics, for a moment, let's just follow the water.

♪ ♪ YEHIA JEDALLAH (in Arabic): ♪ ♪ ♪ ♪ McEVERS: Yehia Jedallah lives with his father and brothers in a neighborhood called Al-Shati.

For 4,000 years, people here have gotten their water from wells, but because the aquifer is now overdrawn, the salt water is intruding from the sea.

JEDALLAH: (people calling in background) ♪ ♪ (man speaking on loudspeaker in distance) (gun fires) McEVERS: Today, 97% of Gaza's wells are unfit for human consumption.

If nothing is done, the United Nations predicts that Gaza will soon be unlivable.

(man continues speaking, people whistling) JEDALLAH: CROWD (chanting): Allahu akbar!

Allahu akbar!

♪ ♪ JEDALLAH: ♪ ♪ McEVERS: Watching this, you might think, "Whoa, that is really bad-- for them."

But you're also probably thinking, "My water problems are never going to get that bad."

But here is the thing: Experts are saying that in ten years, the worldwide demand for water will outstrip supply by 40%.

So, statistically at least, for many of us, Gaza is the future.

♪ ♪ Maybe you think this couldn't happen in one of the richest nations in the world.

Well, take a look at this-- the Salton Sea.

♪ ♪ (birds twittering) A place that once attracted more visitors than Yosemite National Park.

REPORTER: Here is truly a miracle in the desert.

Today, the Salton Riviera beside the blue Salton Sea is the place for you to take charge of your future.

This unusual city has a date with destiny.

♪ ♪ McEVERS: That date with destiny did not end well.

Water scientist Jay Famiglietti understands what happened here.

I like to think of him as the water detective.

Welcome to my office.

♪ ♪ McEVERS: Jay told me that we used to let fresh water reach the Salton Sea.

(wind howling) But now, we have diverted the water for other uses.

The only water that reaches the sea is farm run-off... which is so polluted that the entire basin is a public health risk.

One of the things that I think is really clear from looking at the satellite picture is that the need for humanity to grow food is really putting one of the biggest fingerprints on this global map of changing water availability.

And so, what that says to me is that we're having a huge impact, and so we really need to think about it.

McEVERS: And for Jay, the Salton Sea is also a glimpse into the future.

FAMIGLIETTI: If we think about worst possible situation, take a big city like Phoenix...

Runs out of water, this is what it might look like.

(wind howling, metal rattling) McEVERS: Jay often gets accused of being Dr. Doom and Gloom.

CONTROLLER: Rock, R.C.

countdown one.

McEVERS: But get him around his rockets, and he perks up a bit.

CONTROLLER: Clarify range for screening, go for launch.

FAMIGLIETTI: I'm literally getting the chills, and it's not from the cold weather.

McEVERS: The total amount of water on Earth does not change.

You can't make it or take it away.

So, the question is: Where does it go?

♪ ♪ To answer that, Jay and his colleagues at NASA created the GRACE mission.

MAN: AFDS is ready for launch.

McEVERS: And now, after 15 years of successful measurement, GRACE is getting a major upgrade.

CONTROLLER: F9 is in startup.

MAN: LD go for launch.

Ten, nine... WOMAN: Nine, eight, seven... FAMIGLIETTI: Yeah, it's a huge deal for, obviously for me personally, but, and I don't want to sound too corny, but it is a huge deal for humanity.

(rocket rumbling) ANNOUNCER: And lift-off of GRACE Follow-On, continuing the legacy of the GRACE mission of tracking the movement of water across our planet.

♪ ♪ FAMIGLIETTI: You know, it reminds me of sending my son off to college, when we dropped him off at the airport.

There he goes, he's gonna do great things.

♪ ♪ CONTROLLER: Stage separation confirmed.

MAN: Stage separation has been confirmed.

McEVERS: GRACE can help us finally understand how water moves across our planet.

♪ ♪ Several of NASA's satellite missions have already been gathering decades of data that can be pieced together.

And they picture the ancient pathways that water has taken since the last ice age, a pulse intimately connected with all life on Earth.

(thunder rumbling, animals and insects calling) Scientists in the Amazon recently discovered that in tropical forests, the trees themselves pump water back into the sky.

Above their canopies, this tree-water gathers into aerial rivers that can flow for thousands of miles.

♪ ♪ But recently, even the most ancient patterns have been changing.

♪ ♪ And we know this because, for the past 15 years, Jay's GRACE satellites have circled the Earth every 94-and-a-half minutes, gathering data.

With remarkable precision, they measure the weight of every snowstorm, flood, and drought.

FAMIGLIETTI: We've been able to construct this pretty incredible map.

And it's a really unprecedented look at how water's moving over the Earth in a way that we've never been able to do before.

And we see a very, very distinctive pattern.

The wet areas, they're getting wetter, and the dry areas in between are getting drier.

The availability of water is much more fragile and tenuous than we think, and so, even in the developed world, we shouldn't take it for granted.

♪ ♪ McEVERS: I live in Los Angeles, and one of the things that worries me the most is drought.

♪ ♪ REPORTER: Cape Town's main reservoir is a dust bowl.

Cape Town is about to find out whether a city can survive when the water runs out.

Day zero has arrived.

McEVERS: Drought hit South Africa in 2015, and for the next three years, they had almost no rain.

The city of Cape Town was within days of shutting off their taps.

We sent a team to film the approach of day zero.

And as they followed the water, the trail took an unexpected and dark turn, out of the city and into the once wealthy farmland of the Western Cape, where farmers were dying with the stress of the drought.

BURRE BURGER: I lost three friends during this drought who took their own lives.

Because they... they had no hope for their farms, they had no hope for nothing.

And that's the thing why we still try to do what we do.

McEVERS: Burre Burger's charity delivers water and feed for livestock to farmers who are no longer able to farm the land.

(people talking in background, tap squeaking) WOMAN: Well, we are on the, on the point that we are basically giving up.

Four years since we last had proper rain.

Most of our animals we had to get rid of.

It's a battle against... (chuckling): Nature.

(engine idling) BURGER: The thing with drought is, the farmers know how to farm for a year, or maybe a year and a half, but not for six, seven, eight years.

On some of the farms, they had no rain for almost seven years now.

(flies buzzing) So, then you struggle.

Then you... you struggle with life.

McEVERS: The U.N. reports that worldwide, areas affected by droughts have more than doubled in the past 40 years.

And droughts affect more people than any other natural hazard.

BURGER: If there is one thing I'm going to change in South Africa through this project of mine, I'm going to bring back unity to our country.

(man speaking Afrikaans) BURGER: We try to get people together.

And it's because of water.

That one molecule.

(laughs) Yeah.

ALL: Amen.

McEVERS: If you're caught in the middle of a drought, it's easy to imagine that the whole world is running out of water.

Far from it.

In fact, as the GRACE data shows us, the moisture lost in a drought-stricken area almost always finds its way to somewhere else.

FAMIGLIETTI: One of the consequences of a warming world is that the atmosphere can hold more moisture.

And if the atmosphere can hold more moisture, that means it's gonna drop more moisture.

McEVERS: When water is on the move so is Mike Olbinski.

We gotta haul ass!

(engine revving) McEVERS: As a professional storm chaser, he is one of the few people who benefits from new weather extremes.

Yeah, look at that.

It's really looking good out there.

♪ ♪ Yeah, it's really gorgeous.

(camera clicking) McEVERS: Most storm chasers want to see tornadoes, but Mike tracks these rare giant thunderstorms known as supercells.

(phone camera clicks) ♪ ♪ Oh, this is stunning.

(bird squawking) OLBINSKI: At this point, it's pretty, but I want a mothership supercell, so we'll see if we get that.

And so hopefully, it's gonna be a beastly supercell with some good structure after a while.

(wind whipping) All right, I think we should go.

It's getting close, and I wanna get in front of it.

(thunder rumbling) McEVERS: Supercells can be ten miles high, 25 times the volume of Mt.

Everest, and drop billions of gallons of water in just hours.

(thunder rumbling) They produce softball-sized hail, high winds, severe lightning, and even tornadoes.

(thunder rumbling) In the American Midwest, storms like these are a third more common than when Mike was born.

♪ ♪ Big storms are dropping ten percent more rain than they did 25 years ago.

OLBINSKI: I felt a drop.

MAN: That's hail!

OLBINSKI: Oh, was that hail?

Ow!

Hey, probably gotta go!

Yeah!

That hail just hit me in the head!

McEVERS: And it's not just moisture.

Storms feed on heat, so warmer conditions also mean more raw power.

Whoo!

(rain falling steadily, thunder rumbling) (exhales) Now the nerves come out, now the adrenaline's pumping.

(thunder rumbling) Whoo!

(people laughing) It's what we freaking live for right here.

(man cheers) This is great-- I hope my exposure is right.

McEVERS: Mike finally finds the supercell storm he's been looking for.

Oh, man, it's so great!

Just, keep, just move slow, baby.

Just move slow.

♪ ♪ (camera clicking) OLBINSKI: This is one of the best supercells I've ever seen.

♪ ♪ It's literally all, like, run by water.

They need this for the crops, and if you didn't have it, then no one would live here.

That was good, man, thanks.

(both exclaiming) (thunder rumbling) That was good.

McEVERS: It has been a good day for the storm chasers.

(thunder rumbling) But these grand movements of water also tell a tragic story-- one we've been tracking all over America.

REPORTER: Supercells have been spotted on the radar.

REPORTER: Tornado alley has already been hammered.

REPORTER: That is a wall of water right now.

REPORTER: Flood waters rising as high as ten feet.

McEVERS: One storm in particular caught our attention.

In September 2018, Hurricane Florence acted strangely as it hit the Carolinas.

REPORTER: Florence will produce catastrophic flooding over parts of North and South Carolina for some time.

McEVERS: Instead of blowing through, like most hurricanes, Florence stalled on the coast.

Like a supersize vacuum, it took moisture from the ocean and poured it onto land as rain.

Florence broke 28 flood and rainfall records for the Carolinas.

LEIGH BELL: That's the top half of our garage.

I don't know where the rest of it is.

McEVERS: We headed to the Carolinas with photographer Gideon Mendel.

Gideon has been documenting the increase in flooding around the world.

Can we just pause for a second so I can, like, get the reflection of the church?

That'd be cool.

I guess I have kind of fascination with this landscape.

There's something about a flooded environment which I actually find very visually alluring.

MAN: He ain't gonna come in the boat.

That's a big old blue runner!

MAN 2: He'll chase ya... MENDEL: At the heart of the whole project is a series that I call "Submerged Portraits."

(knocking) And, you know, it's a series of pictures of people affected by flooding, engaging with the camera directly.

Would you, would you be open to us talking to you and photographing you, maybe?

Yeah.

(water sloshing) GEORGE: I've been 34 years on this beach, and this is...

I've never seen it like this.

And if they say it's coming another three feet, you know, it'll just about reach the roof of my building.

I got a lot of tools in there.

(clears throat): I thought we was gonna be all right.

(voice breaking): But I guess not.

I'm so sorry, George.

MENDEL: That's it, just... Can you come just a little bit forward here?

That's good, perfect-- all right.

It is quite amazing how long people will sit there and stand there in the water and engage with me.

15, 20 minutes, half an hour sometimes... (birds twittering) (camera clicks) Portraiture and the direct gaze at the camera, for me, is so important.

(thunder rumbling) McEVERS: For Gideon, the increase in flooding is a global story.

(speaking indistinctly) (camera clicks) McEVERS: In the past 12 years, he has photographed 20 floods in 13 countries.

(camera clicks) ♪ ♪ (camera clicks) MENDEL: The water connects all the people I photograph.

(camera clicks) Despite huge differences in culture, class, location, when the water's in your home, they have a shared vulnerability to flooding, to climate change, to global warming.

(camera clicks) ♪ ♪ McEVERS: Extreme rain and flooding is now four times more likely than it was 40 years ago.

♪ ♪ Hurricanes are 60% more powerful than 50 years ago, and their top wind speeds have increased 25%.

You're really, really photogenic.

McEVERS: So, there's more flooding, and there's more drought, and, honestly, it's amazing that farmers are still able to feed the world.

But what I didn't realize is the extent to which farmers are tapping into a secret stash of water... A hidden source that is not affected by droughts or flood.

Water that lives underground.

Deep under our feet, there are aquifers that together hold more water than all the lakes and rivers on Earth.

They don't often look like this-- most groundwater is held in layers of rock or sand.

Many aquifers contain what's called "fossil water," and what that means is, it took thousands of years to get here.

♪ ♪ It is not easy to follow the water that is hidden underground.

But you might have seen these circles from a plane.

With a metal straw and a diesel engine, we can reach aquifers 3,000 feet down.

Humanity started this kind of industrial pumping of water just a hundred years ago.

And it's been so successful, nearly half the water used for farm irrigation comes from underground.

This water grows almost one-fifth of the world's food supply.

We have been draining aquifers with little idea of how much water is in them.... until now.

(people talking in background) When Jay and his colleagues launched GRACE-- which stands for Gravity Recovery and Climate Experiment-- they designed the system to do the impossible: to see into the Earth's crust using gravity.

FAMIGLIETTI: We can see storage changes in the world's great aquifer systems from space.

I like to say GRACE works like a scale in the sky.

McEVERS: GRACE is actually two satellites.

As they approach an area that has just had a storm, for example, the extra weight of that water pulls the satellites.

FAMIGLIETTI: So, as they approach this region that has more mass and therefore a greater gravitational tug, the first one gets pulled down and accelerates a little bit.

Second one comes in, it gets pulled down, accelerates a little bit.

So, the distance between the two changes.

That's the measurement that the GRACE mission makes.

It's the position of the satellites.

McEVERS: In this way, GRACE can tell us the difficult truth about our aquifers.

FAMIGLIETTI: Sadly, groundwater is, is barely managed around the world, and so groundwater is quietly disappearing.

♪ ♪ McEVERS: In California, the groundwater took thousands of years to accumulate, and we're using this fossil water much faster than it can be replaced.

FAMIGLIETTI: This is the definition of unsustainable.

The disappearance of groundwater is really threatening the water security of the Western U.S., and really, no one's talking about it.

♪ ♪ McEVERS: Jay's been doing what he can to get the message out.

BILL MAHER: He's a professor at the University of California at Irvine and senior water scientist for NASA's Jet Propulsion Laboratory, Jay Famiglietti!

Jay!

(audience cheering and applauding) All right, so, finally, a witness who will tell us expert testimony about this... FAMIGLIETTI: You know, here's the thing.

The drought situation is much worse than I think is generally perceived.

And this may be why we're not getting the public response that we want.

Yes, show that chart-- look at this.

It's green and now it's red.

Now, doc, I'm not a scientist... Red is bad!

Red is bad.

That's what I know, red is bad.

(audience laughter fading) (birds twittering) McEVERS: It's pretty safe to say that Jay is frustrated more people are not taking his breakthrough insight more seriously.

But the truth is, it's hard to stop pumping the water.

Farmers need water.

All of us need food.

And if anything, we just keep pumping faster.

STEVE ARTHUR: So what we're doing here is, we just got down to setting casing... McEVERS: It wasn't until we met Steve Arthur that we got a sense of the scale of these wells-- he drills 30 new wells each year.

(tool buzzing) FAMIGLIETTI: Can you see the water table fall over time?

ARTHUR: Well, I remember when I was a kid, we would drill in the Madera area.

We would go 240 to 300 feet.

300 feet was considered a deep well.

Yeah.

Now we're replacing those wells with 500- and 600-foot wells.

Oh, okay!

MAN: How much pressure?

McEVERS: Steve says it's become a kind of race to the bottom.

If one farmer drills deep to get the water, the next farmer drills even deeper.

And all this drilling is not cheap.

FAMIGLIETTI: If I'm a customer, I don't have a well, I want you to dig a new well.

It's 2,000 feet deep.

How much is that gonna cost me?

It's gonna cost you a little over half a million.

Whoa!

Half to three quarters... Whoa!

Depending how it's constructed.

Okay.

McEVERS: That is an insane amount of money.

Which tells you that water is big business.

It also tells you why so many of America's aquifers are running dry.

♪ ♪ The Ogallala aquifer-- one of the biggest on Earth-- lies beneath eight Midwestern states, from Texas to Nebraska.

♪ ♪ ♪ We got to go ♪ ♪ We got to go ♪ ♪ ♪ This is Ogallala aquifer water.

Comes through the water system over here with the big storage tank.

♪ ♪ McEVERS: Like most of the families in St. Francis, the Callicrates have farmed here for generations.

MIKE CALLICRATE: My grandkids, Wilson and Charlie, will be the fifth generation on this land.

♪ ♪ McEVERS: But Mike does not see High Plains farming as a success story.

CALLICRATE: We have just flat squandered this resource over the last 40 years that I've been associated with, with farming and ranching and cattle production in this area.

If we would stop pumping today, it would take 6,000 years to, to recover the, the amount of water that we've taken out in just the last 40 or 50 years.

McEVERS: The aquifer under St. Francis is already a third empty.

Mike blames the industrial model of agriculture-- the one he was taught in college.

CALLICRATE: I've had a front row seat in this disaster, and I hate industrial agriculture.

McEVERS: Most of the water from the Ogallala aquifer is used to grow grain for feed lots full of cows.

CALLICRATE: This is the biggest feed lot in the world off to your left.

It's 130,000 head of cattle in one place.

From a business perspective entirely, you're thinking about the Ogallala aquifer as a gold miner would see a gold mine-- as an asset, as a resource to be extracted and utilized.

And when it's gone, it's gone!

McEVERS: What worries Mike is what happens when the water runs out, and the mining operation moves on.

In St. Francis, Mike thinks industrial agriculture has broken the hope these communities have for a sustainable future.

And it has already hurt the community that lives here.

You know, when we look at this main street of St. Francis, Kansas, what you're really looking at is the approach of industrial agricultures.

It doesn't care about people, it cares about return on investment, it, it cares about a bank account, and everything else doesn't matter.

It's no wonder we're losing rural communities and losing farmers.

McEVERS: Down on the southern edge of the Ogallala, the aquifer is already running dry and putting farmers out of business.

Without the farmers, the local economy collapses.

And if the trend continues, the town of Happy, Texas, is the sign of things to come.

♪ ♪ Four churches, but not a single store open for business.

♪ ♪ Jay knows this underground water problem is not only in America.

GRACE sees into aquifers all over the world.

FAMIGLIETTI: There's 37 major aquifers around the world.

And over half of them are past sustainability tipping points.

Which means we use more than is being replenished on an annual basis, and we're technically mining them.

McEVERS: Given that nearly half of the water used for farm irrigation depends on these aquifers, you can understand Jay's alarm.

FAMIGLIETTI: So, as that groundwater disappears, our ability to produce food for the world's growing population will be threatened.

McEVERS: In fact, there's growing evidence this is already happening.

And it is having serious consequences.

This story begins in Syria in 2006, when the country was hit by the worst drought in 500 years.

Farmers began to overdraw water from their aquifer.

And with GRACE, Jay could see it as it was happening.

FAMIGLIETTI: We saw the Syria hotspot, and we saw that groundwater depletion way ahead of time.

And we did try to communicate that to the Pentagon, State Department, um, and it's, you know, it's tough, it's tough to get attention.

You know, who are you?

You're some professor that walks in with a research paper and a colorful map, and it's hard to really convey what's, what's happening.

But, you know, we made our efforts repeatedly.

McEVERS: I was actually reporting in the Middle East at the time.

And when protests, and later war, broke out, we knew it was connected to the drought.

But what we didn't know was how it was connected to a much larger global water story.

(chanting) REPORTER: Now the protesters are battling for regime change.

♪ ♪ (car horns honking) ♪ ♪ (wind howling) (car horn honking) McEVERS: The Za'atari refugee camp in Jordan is home to about 80,000 refugees from Syria's civil war.

(whistling) (truck brakes) ♪ ♪ Troy Sternberg is a geographer from Oxford University and another detective who follows the story of water.

He wrote a paper showing how global droughts caused a chain of events that influenced not only Syria's war, but politics around the world.

♪ ♪ His interviews with refugees like Mahmoud Al-Kadr add a human dimension to the data.

Mahmoud, could you please explain what, what brings you to the refugee camp?

What factors drive you here?

(speaking Arabic) The lack of rain have reduced the amount of crops growing naturally.

So, people had to go and start getting water from underground.

But they also stopped the diesel.

So, there is no diesel to be able to pump water.

So, there was no, no water to drink.

There is no food with the drought.

We start eating the grass.

♪ ♪ McEVERS: 85% of Syria's livestock died and hundreds of thousands of farming families like Mahmoud's had to abandon their farms.

They ended up settling outside Syria's big cities.

♪ ♪ Troy's research shows that there were much larger global forces at work-- more than just a drought in Syria.

♪ ♪ When Troy followed the water, he documented a series of droughts that connected Russia, China, the Arab Spring, and politics across Europe.

♪ ♪ STERNBERG: This globalized world is very interconnected.

Things that happen in one part of the world can have a great knock-on effect in another part of the world.

Sometimes we talk about this as the butterfly effect, but I think it's more direct.

And it's really climate, drought-- anything that happens that we, we can't control or can't count on.

One way might be to look at it as a series of dominoes.

McEVERS: It was a set of dominoes that collapsed over a ten-year period.

And it started when Australia faced a drought described as "a 1,000-year event."

♪ ♪ REPORTER: Australia is dying of thirst.

And where there used to be water, there is only dry, cracked earth.

McEVERS: During the winter, countries in the Northern Hemisphere depend on the Southern Hemisphere for wheat.

And the drought threatened Australia's ability to supply this winter wheat to the rest of the world.

♪ ♪ Then, the next domino fell.

In 2010, mainland China suffered its own drought.

♪ ♪ REPORTER: The drought ravaging China is being called the worst in a century.

♪ ♪ STERNBERG: Wheat is a global commodity traded on the international market, so liable to market forces.

So, if China needs more wheat, my thinking was: does this have another impact somewhere else in the world?

♪ ♪ McEVERS: Troy followed the trail to the Middle East, where farmers were suffering from their own drought.

And with the wheat issues in Australia and China, it affected food prices in Syria and Egypt.

♪ ♪ STERNBERG: So, as Egypt needs more wheat and China needs more wheat, there is less wheat available.

McEVERS: Then, in 2010, another domino fell.

Russia, the largest exporter of wheat to the Middle East, was gripped by a devastating heat wave.

♪ ♪ (Vladimir Putin speaking Russian) (translated): Due to abnormally high temperatures and drought, I believe it's reasonable to introduce a temporary ban on grain and wheat products export.

McEVERS: With wheat exports from Russia reduced by 80%, world prices skyrocketed.

REPORTER: It's Christmas for the speculators as prices drive upwards, wheat by a whopping 130%.

STERNBERG: There's a limited supply, great demand... McEVERS: Speculators on the commodities market saw an opportunity-- they bought and held on to the wheat while prices rose.

Richer countries can stockpile the grain.

STERNBERG: They have a great fiscal and infrastructure power-- ships around the world that can transport wheat.

Other countries don't have this possibility.

McEVERS: By the time some Arab governments realized what was going on, it was too late... Prices for bread went way up.

STERNBERG: In Egypt, the wheat prices skyrocketed 300% and more.

REPORTER: In recent weeks, there have been long queues in front of bakeries.

Rising prices have even caused riots in the Nile delta.

McEVERS: Hunger began to fuel people's anger toward their governments... (chanting in Arabic): STERNBERG: We see food riots in Cairo... REPORTER: After Friday prayers, hundreds of thousands of demonstrators gathered in Tahrir Square.

REPORTER: The people of Egypt have toppled their leader.

Egypt will never be the same.

And that's where the Arab Spring really brings everything together.

♪ ♪ McEVERS: Which brings us back to Syria.

Inspired by the Arab Spring uprisings and suffering from their own drought, Syrian protesters also took to the streets.

REPORTER: The Syrian government made it very clear today that it will tolerate no dissent.

(guns firing) McEVERS: Events escalated... (explosion echoes) And Mahmoud's family was caught in the crossfire.

(speaking Arabic) INTERPRETER: I lost my son and I lost my wife in this war.

My wife was on the way to the market in Damascus.

On the rooftops, there were some snipers and she have got a shot in the head.

So I'm afraid for the rest of the family, and we came here, and here they were helping us, and they, they were supporting us.

McEVERS: Water or drought is of course only one factor that influenced these events.

But when a million refugees fled to Europe, the falling dominoes came down much closer to home.

REPORTER: These people calling for the regime to change are on the back foot.

They're being forced from their homes and pushed towards the border with Turkey.

As migrants pour into Europe, in the U.K.-- we see this filmed on TV throughout the summer of 2015-- it plays very well to the Brexit Leave debate.

(laughing and applauding) REPORTER: The Leave campaign celebrates as the U.K. votes to cut its ties with the European Union.

McEVERS: The fear of mass migration directly impacted the Brexit vote in Britain.

And, according to Troy, even had an impact here in America.

STERNBERG: If we go further, this news plays out in the U.S. Donald Trump gets elected on this very nativist "America first" theme.

We will build a wall.

McEVERS: Troy's concern is that the water crisis can spark an even more dramatic chain of events in other parts of the world.

STERNBERG: What will we see next?

What happens if we have a climate disaster in India or China or Mexico or Pakistan?

Then we're talking about very serious dynamics and very serious outcomes.

♪ ♪ McEVERS: In our globalized, interconnected world, no country can afford to ignore water and climate.

For the past four years, the World Economic Forum has ranked the impact of the water crisis alongside weapons of mass destruction, disease outbreaks, and failure to address climate change.

♪ ♪ Looking for solutions, we came back to the U.S., and we went to New York City.

♪ ♪ And we reconnected with Giulio Boccaletti, who wrote a seminal report for the World Economic Forum.

In it, he calculated that ten years from now, the world will need 40% more fresh water than it can supply.

♪ ♪ But Giulio thinks that if more people knew about New York's water story, they could avoid that grim fate.

New York has a very particular experience, but one that I think holds the key to the solution to the water crisis for the whole world.

I suspect most New Yorkers, you know, assume that water just comes out of the tap, and yet behind that tap, there is one of the most sophisticated integrations of nature and water that has ever been seen on the planet.

♪ ♪ (people talking in background) McEVERS: Giulio took us to meet the C.E.O.

of WaterAid America... (espresso machine running) Sarina Prabasi.

While Sarina has worked on water issues all over the world, here in New York, she and her husband also own a coffee shop.

She cares a lot about New York's water.

Water is the life blood of our business.

Like, there is no good coffee without good water.

So you work for WaterAid, and what do you think people imagine when they think about the water crisis?

People have thought about the water crisis as something elsewhere.

But now I think there is more understanding that the water crisis is all around us.

So, New York had a... a proverbial fork in the road, right?

And had to take one option rather than the other.

In the '80s, the water was getting very polluted... Mm-hmm.

And in the '90s, I think there was a real strategic decision to make of how the future of New York City water would be handled.

One way could have been a bit more business as usual, invest in infrastructure... And this was, we're talking about a treatment works, right?

You know, a treatment plant.

Treatment, filtration.

Right.

Technology: high cost, I think $6 billion.

Definitely a more energy-intensive approach.

BOCCALETTI: And what about the alternative?

PRABASI: And the other option was to really look at where the water is coming from.

♪ ♪ McEVERS: Because where the water was coming from was the Catskill Mountains.

♪ ♪ So, instead of a new treatment plant, New Yorkers chose to invest in a nature reserve that doubles as a giant water farm.

PRABASI: The water is being filtered by trees.

This natural environment serves like a sponge holding the water.

McEVERS: A forest replaces heavy industrial infrastructure, with the added benefits that the place runs itself, maintenance-free.

And supplies 90% of New York's water.

PRABASI: For New York City, it was a radical choice for the time, but it was going back to something that has been working for millennia.

The water cycle belongs to nature.

BOCCALETTI: In a way, it's the most simple of answers.

Back into nature-- find the answer back at the very beginning, from the ecosystems that we came from, and yet it can support one of the most modern societies on the planet.

♪ ♪ McEVERS: Making the most of our connection to nature is undoubtedly the best way forward.

But what works for a wealthy city in a moist climate won't necessarily work everywhere.

FAMIGLIETTI: I don't think we're really gonna find any silver bullets.

I think as we look around the world, region by region, each one is going to need a different portfolio of approaches to manage their way through water scarcity.

♪ ♪ McEVERS: Maybe it's not surprising, but we found, in the places on Earth where there is less water, people value it more.

And of all the places we went to, it was in the Middle East where we saw not only the challenges ahead, but also glimpses of hope.

Since its inception, Israel has valued water much like America values oil.

They even went to war over it.

So here, controlling water is a matter of survival.

Israel recycles 90% of its water, compared to just one percent in the U.S. And they achieved this not just through wealth and power, but through winning hearts and minds.

(speaking Hebrew): ♪ ♪ McEVERS: It's this appreciation of water that Mike Callicrate would like to see here, in the U.S.

I would like to see us not pump a drop more than what the recharge rate is.

And we know what those numbers are.

Water is the public's resource and it should be used responsibly and preserved.

We can do this.

♪ ♪ McEVERS: So, in the end, each of our water experts agreed we can do this.

That, unlike some threats we face, the water crisis is solvable.

But we are vulnerable.

And in this finely tuned globalized world, if we don't respect water or the climate, collapse will follow.

(thunder rumbling) ♪ ♪ (thunder rumbling) ♪ ♪ When we understand the connections-- where our water comes from-- then we value it for what it is: the fuel of life itself; the molecule that made us.

(thunder rumbling) To order "H2O: The Molecule That Made Us" on DVD, visit ShopPBS.org or call 1-800-PLAY-PBS.

This program is also available on Amazon Prime Video.

♪ ♪ Follow the story of water at pbs.org/molecule.

♪ ♪ Join the conversation at #MoleculePBS.