(thunder crashes) (water droplet plunges) ("Wade in the Water" plays) (choir) ♪ Wade in the water ♪ (Shane) Always in search of equilibrium... (choir) ♪ Wade in the water, children ♪ (Shane) They follow the path of least resistance... (choir) ♪ Wade in the water ♪ (Shane) ...creating ecosystems... (choir) ♪ God’s gonna trouble the water ♪ (Shane) ...and shaping cultures as they flow.

(choir) ♪ Wade in the water ♪ ♪ Children, wade in the water ♪ (Shane) Our ancestors found them, tamed them, and harnessed their power to build the modern world.

(choir) ♪ Wade in the water ♪ (Shane) And in the process, transformed rivers into what we needed them to be.

(choir) ♪ God’s gonna trouble the water ♪ (explosion) ♪ We are the sons and the daughters ♪ (Shane) Humans have moved mountains to contain them, funneled them into our fields, and diverted them into our cities.

(sprinkler spraying) Forgetting, perhaps, that while rivers have written our destinies for time immemorial, flipping that script might not work out the way we want.

(vocalizing) What happens to the world we’ve built... -(wind blowing) -(water rushing) ...when the rivers that sustain it become something else?

(intense music) ♪ Welcome to the age of humans, where one species can change everything.

And what we do reveals who we truly are.

This is Human Footprint.

(siren wailing) ♪ (record scratch) (mysterious music) ♪ (insects chirring) (engine humming) ♪ Comedian Jason Love joked, "Las Vegas has all the amenities of modern society, in a habitat unfit to grow a tomato."

(water droplet plops) ("Feel So Good" by Ma$e) (Diddy) You ready Ma$e?

♪ Party people in the place to be ♪ ♪ It’s about that time for us to ♪ (screams) (Ma$e) Yeah, uh-huh.

♪ Yo, what you know about goin’ out ♪ ♪ Head west, red Lex, TV’s all up in the headrest ♪ (Shane) It’s a glittering oasis of extravagance where visitors can lose themselves in an alternate world of luxury and fantasy while ignoring the harsh reality.

(casino games beeping) (button clicks) (eerie music) (Colby) We get 90 days above a hundred degrees.

We are the driest metropolitan city in the United States.

We get less rain than any other metropolitan city by almost half.

("The Jump Off" by Lil’ Kim) (Shane) Meet Colby Pellegrino of the Southern Nevada Water Authority.

She’s been riding horses around this parched city her entire life.

(Lil’ Kim) ♪ Been gone for a minute ♪ ♪ Now I’m back with the jump off ♪ ♪ Goons in the club in case somethin’ jumps off ♪ (Shane) If you ask Colby, the most valuable thing in Vegas isn’t locked up in a casino vault.

(Colby) This is the electrical control room that helps operate and supply the energy that that little pump needs to fill our valley with water.

(hip-hop music) (Shane) The pump station is like Oz’s man behind the curtain.

It’s the invisible linchpin of an intricate system that makes Las Vegas possible.

(Colby) This pump station has 34 pumps in it.

Just to give you an idea of the magnitude, one of those pumps could fill an average residential swimming pool in 20 seconds.

-(girl screams) -(water splashes) (Shane) The pumps move water from the Colorado River to two treatment plants that can each deliver 900 million gallons a day to the valley’s homes and businesses.

(soft music) (Colby) If you were to sort of peel up the streets and the sidewalks, there’s water infrastructure everywhere.

Larger pipes that feed major areas, and then as you branch off they get smaller and smaller and smaller, so that when you turn on the tap, it’s there.

You could not inhabit the Las Vegas Valley without the water infrastructure that we have.

♪ (Shane) But the engineering that makes life in Las Vegas possible is part of a tradition that started a long time ago... (whooshing) ...on a continent far, far away.

(man) One, two.

One, two... ("Slim’s Return" by Madlib) (fast-paced vocalizations) ♪ (Giulio) If you walk around Bologna, it’s a reminder of how powerful the engineering of water can be for urbanization.

♪ (ocarina music) (Shane) Meet Giulio Boccaletti, whose virtuosity on the ocarina has made him something of a celebrity in Japan.

♪ He’s also a geophysicist, whose recent book explores humanity’s relationship with the world’s most important molecule.

(water rushing) (Giulio) Water is the primary agent that transforms the landscape around us.

(slow, suspenseful music) Water can cut through mountains or transform floodplains, can wash away cities.

Water can change your life in a day.

♪ So it’s a really powerful thing that we need and we fear.

Once we start converting natural ecosystems into ecosystems that are functional to our life, we have to master water.

We have to domesticate water in order to bring it to where we need it.

♪ (Shane) So why did you want to have this conversation in this place specifically?

Well, this is an important place.

The oldest mason-built hydraulic infrastructure in Europe.

(tranquil music) (Shane) The Casalecchio dam re-routed water from the Reno River to generate hydropower miles away, launching a process of early industrialization that made Bologna the wealthiest city in Europe for nearly 300 years.

♪ (Giulio) Everything that you could mechanize was done with water.

And this, in the 1300s, was like discovering oil, right?

It completely transformed the economy.

(machinery clattering) And so, in a way, it changed the world, right?

Because it was the first industrializations all powered by water.

But more importantly, it changed institutions.

(soft, tense music) (Shane) As Giulio sees it, no one person can tame a force as potent as water.

We have to come together.

And exactly how we do that, and for whose benefit, reveals a lot about what we value.

♪ (Giulio) The visible marker of it is, of course, the infrastructure we build, but the real ingredient is institutions that we construct in order to manage this on our behalf.

(Shane) The institutions Guilio’s talking about are the bedrock of our society, the governments, laws, and social structures that determine how we harness and distribute a precious resource.

(mellow music) Whether that’s in 14th-century Bologna or 21st-century Nevada.

(announcer) Casinos, hotels, good food, and entertainment.

And don’t worry, there’s always tomorrow.

(Colby) Las Vegas is originally formed because there were springs.

Las Vegas means "the meadows."

♪ As the community grew, the spring started to dry up.

So we saw more and more wells.

Those wells began depleting the aquifer at a rapid rate until we tapped into the Colorado River in the late ’70s.

♪ (soft music) (Shane) From headwaters in the Rocky Mountains, the Colorado River travels 1,450 miles through seven states, then into Mexico, before finding its equilibrium in the Gulf of California.

(narrator) The river had to be regulated.

No more floods, no more droughts.

♪ (Colby) Nevada has the smallest allocation of Colorado River water.

We’re actually allocated 1.8% of the available resources on the Colorado River.

♪ (Shane) But that water allowance was enough, at least at first, to support a booming population.

♪ (Colby) When I was born, there were 300,000 people that lived here.

There’s 2.3 million now.

Wow!

As the city has grown, so has its thirst.

But even in the "City of Sin," there’s one vice you can’t indulge... -(sprinkler sprays) -(woman sighs softly) ...wasting water.

(siren wailing) ("Bad Boys" by Inner Circle) (Inner Circle) ♪ Huh!

Bad boys, bad boys ♪ ♪ What you gonna do ♪ ♪ What you gonna do when they come for you?

♪ (Cameron) People want to have these beautiful lush green lawns, they want to feel like the American dream, but here in Las Vegas, we have a limited water supply.

(mellow music) (Shane) This is Cameron Donnarumma.

His official title is "Wastewater Investigator," but ’round these parts, he’s what’s known as a "Water Cop."

(water dribbling) (Cameron) When we come across a water waste violation occurring, I’ll get out of the vehicle, I’ll go ahead and document that on video.

If they have no previous history, it’ll be considered a warning.

However, if we see the water waste violation is still occurring, a fine starts at $80.

If we come back and the violation is still occurring, it will double to $160 and so on.

♪ (Shane) In the most extreme case, is there like prison time that’s associated with it?

No prison time involved.

But we do have educational visits.

(Shane) Most of that education focuses on landscaping that can thrive here in the desert.

(mysterious music) (Colby) There is absolutely nothing that grows in the Mojave desert without irrigation.

(sprinkler spraying) So the number one consumptive use, by and large, is outdoor irrigation.

(water spraying) (Shane) The problem isn’t just that people want green lawns in a desert.

♪ It’s also that outdoor irrigation can’t be recycled.

(Cameron) So anytime you turn your sink or shower on, generally that water will be recycled and we can reuse it again.

Outdoor water use is a one-time use.

(water spraying) Once it goes out into the gutter, it evaporates, we can never see it again.

(water trickling) (Shane) Las Vegas, by necessity, is on the cutting edge of urban water efficiency.

(tranquil music) In the last 20 years, they’ve limited pool and fountain sizes, forbidden evaporative cooling systems, restricted car washing, and built infrastructure that recycles nearly 100% of the water used indoors.

♪ They’ve also incentivized the removal of over 200 million square feet of turfgrass, saving roughly 10% of their Colorado River allocation.

(Colby) This last year, 2023, we used the same amount of water we did in 1992, despite doubling our population during that time.

(Shane) But the Colorado River, like many around the world, is struggling to meet the needs of its other users.

(Colby) There’s over 40 million people that rely on the Colorado River.

(Shane) And while Western cities jockey for Colorado River water, the straws they’re sipping from are nothing compared to the big straw that gulps down almost 80% of the river’s flow... (somber music) Agriculture.

(sprinklers spraying) And even as our demands grow, the supply is dwindling.

(Colby) All of the predictions are that the Colorado River’s flow is going to decrease throughout time.

(Shane) We built farms, cities, and lives in a desert.

And to make it all possible, we used our species’ transformative powers to re-engineer a river.

(Giulio) So, in the span of a hundred years, we’ve basically transformed the hydrology of the entire planet.

(whooshing) We’ve converted hydrology, which is the natural way in which water manifests itself, into hydraulics to support modernization and industrialization.

(eerie music) So, I’d say, by now, we are the plumbers of the planet.

(whooshing) With that power comes the responsibility of deciding what to do with it.

(sprinkler spraying) (Shane) And the way we choose to flex that power can rewrite the stories of people, cultures, and ecosystems.

(Giulio) We imagine our future and author it, that’s an extraordinary trait, but we also sometimes imagine futures that become impossible to sustain.

(soft music) (water flowing) (Shane) Our technological overhaul of the Colorado River... (water lapping) ...began more than a century ago... (whooshing) ...as the U.S. was trying to populate the West... (whooshing) ...while transforming itself into a new kind of superpower.

(train bell clanging) The river was a key to both goals.

♪ (whooshing) You ever get tired of seeing this?

(Gus) No, I’ve worked in industrial places -most of my life.

-Yeah.

(Gus) Nothing as visual as this.

I mean, it’s pretty incredible.

(Guru) ♪ Skills, top rank, point blank, we vital ♪ ♪ Spit flows, rip shows, peep the recital, skills ♪ (Shane) Gus Levy used to be a mechanic in the Navy.

He worked on ships, submarines, nuclear power plants, and eventually dams.

-(DJ Premier Scratching) -♪ My Microphone ♪ (Shane) So, you really like fixing humongous things is basically what it is.

(Gus) Yeah.

Yeah.

Yeah.

(Shane chuckles) (Guru) ♪ Skills ♪ (Shane) Today, Gus manages the Glen Canyon Dam, a 710-foot-tall concrete giant in northern Arizona.

(soft music) The inspiration for the Glen Canyon Dam was its downstream predecessor, the Hoover Dam.

(hip-hop music) The tallest in the world when it was built in 1935, Hoover was conceived to bring water and hydroelectric power to people across the Southwest.

♪ And the world took notice.

♪ The Hoover Dam ushered in a global age of mega-dams, which continue to transform the world’s rivers... ♪ ...including here at Glen Canyon, a few hundred miles upstream of the dam where it all began.

♪ (Gus) So, I think they poured from 1960 to 1963 around the clock.

(Shane) Wait a minute.

From ’60 to ’63, they poured concrete constantly?

Yes.

Yes.

(soft music) (Shane) Like the Hoover Dam, the Glen Canyon Dam is a marvel of engineering.

♪ But the water it was designed to capture has been...unreliable.

(Gus) It’s been drier and warmer than it has been in the recent past.

(Gus chuckles) We have a reservoir, which is like a bank savings account for, you know, drier times.

But the other thing is this place makes power, -right?

-Yeah.

(Gus) The revenues from that power pay for all the operations and maintenance here.

(soft, tense music) That’s where that concrete batch plant was, and those rails are under the water there.

Last year in the spring, they were exposed.

(Shane) Okay.

I’m assuming that’s bad news.

(Gus) Uh, yeah, it’s pretty distressing to see it that low, because they got down just a little bit under the elevation of 3,520.

This place was not designed to run below 3,490.

♪ (Shane) The shallower the reservoir, the less pressure there is to turn the dam’s massive turbines.

In April 2023, the Glen Canyon Dam’s reservoir, also known as Lake Powell, dropped to a level just 30 feet above the minimum required to generate electricity.

♪ (water flowing) The dam was designed for a version of the Colorado River that no longer exists... and maybe never did.

(mellow music) In 1922, seven southwestern states negotiated an agreement, now called the Colorado River Compact, that allocates the river’s water among the states.

But despite warnings from scientists, the Compact commits an exact amount of water to each state rather than a percentage of what actually exists.

And these numbers are based on a series of unusually wet years in the early 1900s.

So, the Compact often promises more water than today’s river can possibly provide.

(water trickling) (whooshing) Lake Powell, first filled in 1980, reached its peak in 1983, and has been dwindling ever since.

Made possible by viewers like you!

(speaking echoes) Human Footprint!

(speaking echoes) -What up?

-Hey, welcome to Echo Cove.

("Drive the Boat" by Pop Smoke) (Shane) Rob Callaway runs a boat rental and guide business out of Page, Arizona.

(Pop Smoke) ♪ Tell ’em drive the boat ♪ (Shane) A town founded in 1957 to help build the dam.

♪ It was pretty quiet when I was there in November, but in the summer, Lake Powell is...a scene.

(Pop Smoke) ♪ Shake it, shake it, shake it ♪ ♪ Tell ’em drive the boat ♪ (Shane) Lake Powell may be a one-of-a-kind hotspot for outdoor recreation, but the canyon walls reveal a harsh reality of this increasingly arid landscape.

(soft, solemn music) (Rob) Here, this is a bathtub ring, as some people refer to it.

And that’s really a good indication of lake levels when the lake is full.

(Shane) Whoa.

♪ So, this is like a big farmer’s tan is what I’m looking at, basically.

Absolutely.

(Shane) Today, the bathtub ring is more than a hundred feet above the reservoir’s surface.

♪ Even as it dwindles, Lake Powell is a striking, surreal place.

There’s really nothing quite like it.

But for many, there was also nothing like the Glen Canyon... ♪ ...the natural wonder that the dam drowned under Lake Powell.

(projector clicking) (guitar music) Tribes and environmental groups protested the dam, knowing the cultural and ecological treasures that would disappear under hundreds of feet of water.

(phone ringing) (whooshing) (Tahlia) My grandfather lived in Tuba City, and when the desert got really hot, we would drive up to Page to Antelope Point in Lake Powell.

("Runnin’" by The Pharcyde) (Shane) Tahlia Bear works with a coalition of tribes advocating for water policy reform.

When she isn’t hard at work, she loves getting to know her new home in Colorado and reconnecting with her childhood stomping grounds.

♪ (Tahlia) Since time immemorial, 30 federally recognized tribes have called the Colorado River Basin home.

But the environmental concerns or the reliance of the river by the tribes in the basin has not been considered in a lot of the decision-making.

(solemn music) (Shane) When the Colorado River Compact was signed in 1922, Native voices weren’t included in the process.

And today, even though some tribes have a legal right to Colorado River water, many don’t have the complex and expensive infrastructure to bring water where it’s actually needed.

(Tahlia) The Navajo nation is just a little bit larger than the state of West Virginia.

And 30% of households do not have running water.

♪ (Shane) In your mind, like, having a seat at the table, should that be the ultimate goal, or should we be thinking about this entire thing differently?

(Tahlia) What I would say is that, overall, the Colorado River needs to be managed as a living whole system rather than a plumbing system.

Mm.

(Tahlia) And if we all want to provide water as a human right, we need to change the management of it.

("3WW" by alt-J) ♪ (Shane) The mega-dams pioneered in the American West were a triumph of human ingenuity, a milestone in our quest to control water.

♪ But they turned a living river into an engineering problem.

And today, that river’s rhythm is dictated not by nature but by our ever-changing demands for water and power.

♪ Below the Glen Canyon Dam, the Colorado River flows through one of the planet’s most extraordinary landscapes.

♪ The Grand Canyon, of course, isn’t underwater.

But it’s been reshaped by this dam nonetheless.

♪ To understand how and to exercise our God-like control of the river to benefit both humans and ecosystems, we need solid data to guide our decisions.

♪ (water whooshing) ♪ And it takes a special kind of person to do science at the bottom of the Grand Canyon.

No one sounds confident in this situation.

(laughs) I’mma just put that out there.

(mellow hip-hop music) ♪ (Matt) Oh, that one got you!

(Shane) Yeah, that one gave me the business.

(Matt) Yeah, from the back.

(Shane laughs) ♪ I have not run into anybody that doesn’t work their ass off down here... -Yeah.

-...and love every second of it.

♪ (Shane) This is Matt Kaplinski.

When he’s not juggling rocks, he’s studying them.

♪ As a geologist for the U.S. Geological Survey, he knows the Grand Canyon better than most.

(Matt) The Grand Canyon is, like, such a natural laboratory.

It’s like a cathedral to geology.

(bluesy guitar music) ♪ (water whooshing) ♪ (Shane) The 5,000-foot canyon walls record eons of Earth’s history.

♪ (Matt) These are the basement rocks of the North American continent.

They formed 1.75 to 1.68 billion years ago and-- Just a little while ago.

(Matt) A little while ago, a little while ago.

(Shane) And the rocks tell a story of dramatic upheaval.

So, when this first happened, that was just a straight line that had a bunch of stuff happened afterwards and squished it into--into the spaghetti.

-Exactly.

-Okay.

♪ All of this history could have been lost underwater, thanks to much more recent upheaval at our own hands.

(Matt) The initial plans the bureau had for the entire river, we look on ’em as, "This is insane."

(projector clicking) In the ’30s, ’40s, and ’50s, it was tame the river time... build the dams.

(Shane) Besides the Hoover Dam downstream and the Glen Canyon Dam upstream, two other dams were planned in the heart of the Grand Canyon.

(Matt) There would have been very little of Grand Canyon, that wasn’t a lake.

Thank God it didn’t happen.

(bluesy music) (Shane) Today, the Colorado River still winds through the canyon it carved, framed by the two giant dams that did get built.

At its peak, the Hoover Dam’s reservoir, Lake Mead, reached upstream more than 40 miles into the Grand Canyon, right up to Separation Canyon, where we’re standing now.

♪ -So, this was a lake.

-Okay.

(Matt) And now that the lake levels have dropped this much, these rapids are sort of re-emerging.

(mellow music) (Shane) Since 2000, persistent drought has lowered Lake Mead by about 140 feet.

And Matt and his team, which today, includes me, have mapped the river’s shore as the canyon adapts to the change.

♪ (Matt) What you’ll do is start up at the top, and every ten feet or so, you’ll stop and put the stick right at the water level and point the glass up to me standing on this instrument.

♪ Shane, you’re right behind that bush there.

You’re gonna have to go to two sticks.

I got you.

♪ (Matt) Nice job, man.

(Shane) Thanks.

Appreciate it.

(bluesy guitar music) Sandbars are the foundation of the whole riverside ecosystem.

And they’re built by sediment flowing downriver.

(Matt) At the Lee’s Ferry gauge, before the dam went in, they were measuring 65 million tons of sand per year were going past that gauge.

(Shane) That’s enough to fill the Empire State Building thirty-eight times.

Most of that sand was carried by spring snowmelt, which turned the Colorado River into a violent torrent.

But today, the Glen Canyon Dam controls the river’s flow, and traps most of its sediment in Lake Powell.

That puts these sandbars at risk.

(Matt) The only tool we have to rebuild sandbars is to use the river itself.

To do that, you need to raise up the flow so that it carries a lot of sediment.

(water whooshing) (Shane) The first "high flow experiment" happened in 1996.

(static crackling) Controversially, it meant releasing extra water without turning the dam’s power-generating turbines.

The flow has to be timed perfectly because it won’t deposit any sediment if there’s none in the river to begin with.

These days, the only major source of sediment is the Paria River, a tributary just below the Glen Canyon Dam.

So when the Paria is pumping, the stage is set.

(solemn music) ♪ (Matt) It’s like a forest fire in a forest ecosystem.

(water whooshing) In the same way, in a canyon river system, floods are a disturbance event that’s healthy for it.

♪ (Shane) These high flow experiments seem to be helping to rebuild sandbars and bring life back to the river, too.

(Lindsay) I think any fish that evolved in this kind of system has to have a little bit of spice to it in order to survive.

("Ain’t Nobody Better" by Yo-Yo) (Shane) This is Lindsay Hansen.

She finds artistic inspiration in the epic landscapes of the Grand Canyon.

(Yo-Yo) ♪ Sendin’ suckas back to the lab, I nab ♪ ♪ The beats to make me a little itty-bitty rich ♪ (Shane) She’s also a biologist studying the Colorado River’s unique fish community for the USGS.

♪ (Lindsay) Okay, sweet.

So, what we have here are some Humpback chub and some flannelmouth suckers.

(Shane) Ooh.

(soft music) Lindsay’s been working here since 2019.

She’s interested in all the fish, but she’s got a few favorites.

I’m gonna assume that is a Humpback chub given the humpbacked-ness of it.

(Lindsay) Absolutely.

Yeah.

So, this is the Humpback chub, the fish that we are out here to study.

(Shane) Okay.

(Lindsay) And this is a really good-looking adult fish.

♪ (Shane) The humpback chub is a federally threatened species.

Lindsay’s catching them to collect data on their growth and reproduction, and, ultimately, to help them survive in a changing river.

(Lindsay) On these trips, we administer a PIT tag.

It’s called a passive integrated transponder tag.

(Shane) It’s the same technology you might use to microchip your pet.

(Lindsay) And then the numbers that you give me will allow us later to see how much the fish grew.

So, if we catch it next time, we’ll be able to see where it moved to.

And we can learn a lot about the fish that way.

(Shane) In a few seconds, the fish is measured, tagged, and sent on its way.

(Lindsay) We multiply that by thousands of individuals, we can learn a lot about how their population is doing.

(upbeat music) (Shane) It’s a huge team effort, with multiple survey trips per year.

♪ (Lindsay) We are on the water for 21 or 22 days per trip.

We will send these small silver boats called ospreys out to collect fish.

They will bring them back to what we call our processing boats, kind of like our mother ship.

We’re fishing day and night, we’re processing fish day and night.

We’ll take a little break to, you know, sleep on the river banks together, and then the next day, we get up and we do it all again.

(Shane) That’s hardcore.

(Lindsay) It’s very hardcore.

Yeah.

(Shane) All this hard work has yielded important discoveries.

(Lindsay) One of those big takeaways is that these fish spawn more often when it’s warmer.

(Shane) The chub evolved in a river with huge temperature swings.

Fed by snowmelt, the river ran cold in the spring and early summer.

(Lindsay) But then when there’s not very much water and there’s hot sunlight directly hitting it, it heats up quite a bit.

(Shane) That’s when the chubs really chub.

(Lindsay) Exactly.

Yeah.

Yeah.

They chub really hard in the summer, and then in the winter, when they’re kind of shivering, they don’t grow very much.

(contemplative music) (Shane) These days, the river is cold year-round; the Glen Canyon Dam generates power by releasing water from the bottom of Lake Powell, where the water is frigid.

Luckily, the chub have a Plan B.

(Lindsay) They often will migrate into and out of the Little Colorado River in order to go up there and spawn and then come back out.

(soft guitar music) (Shane) The Little Colorado is an undammed tributary that joins the Colorado River in the heart of the Grand Canyon.

(Lindsay) The spring that feeds this river is a calcium carbonate spring and it creates this kind of beautiful blue water.

(Shane) The Little Colorado is also milder than the Colorado River itself, allowing the chub to spawn.

It’s a fraction of their former breeding grounds, but the fish are making it work.

And Lindsay’s still hopeful about their future.

(Lindsay) They’re up running rapids, they’re going down rapids.

They’re a little bit tough.

If they can thrive and survive in this really wacky system... -Yeah.

-...then I think we can too.

♪ (Shane) The humpback chub flourished in the untamed Colorado, and maybe we could learn to live with a wilder river, too.

♪ But we’ve got a lot of unlearning to do.

Even here in the grandest of landscapes, humanity’s impacts are impossible to ignore.

♪ (Matt) All right, Shane, check this out.

Here we are in the new Western Grand Canyon.

This landscape didn’t exist 20 years ago.

When Lake Mead was full, it was up there above our head.

And the Colorado River was sending its sediments down into the lake and depositing sand, silt, and clay into these banks.

(soft, bluesy music) (Shane) These sediment layers are exposed because Lake Mead has been dropping for the last two decades, and today’s river is cutting through land that was once lake bottom.

♪ This is like the geologic footprint of humans is what we’re seeing.

(Matt) Exactly.

(Shane) Our impact here is so profound, it’s written into the land itself.

♪ (Matt) The geologic processes will keep going.

Yeah.

But it would be a sad thing if we failed in our job to take care of this place as best we can.

♪ (Shane) Those who know the Colorado River best have always understood that it isn’t here for us, and it can never be all that we’ve demanded of it.

♪ I’m starting to think that taking care of the Colorado, or any river, might mean letting it provide for us on its own terms, not just ours.

♪ Granted, a river doesn’t have, you know, wants and desires.

But it does serve a purpose, a purpose that, like, far surpasses our time as a species on this earth.

For us to step in and say, "Good for you, but we need you to be this, we’re gonna force you to do this," and there’s something about that that’s just deeply frustrating and upsetting to me because I--I personally know what that feels like.

♪ But humans aren’t very good at going back.

And it’s hard to let a river be a river when so many people rely on it being something else.

♪ (whooshing) In California’s Imperial Valley, the Colorado River becomes a glorified irrigation system for the produce that feeds a lot of us.

(Alex) Between Yuma, Arizona, and the Imperial Valley, 80% of the winter vegetables come from our two valleys.

(mellow music) (Shane) Alex Jack is a third-generation farmer, growing winter greens for our salads and alfalfa for cattle.

Whether it’s on the farm... or on the court... for Alex, family’s what matters.

♪ (bluesy guitar music) (Alex) So, in 1914, my grandfather and his brother started with a flatbed truck to start hauling vegetables in Los Angeles.

110 years later we’re, uh, we’re still here, which is very unusual because it’s very tough to keep family farms together.

♪ (Shane) When Alex’s ancestors began farming, the Valley looked pretty different.

(Alex) If you could be in a time capsule and go back to 1900, you’d just see a lot of brush, you’d see all the cactus and tumbleweeds and everything else.

(Shane) The Colorado River forms the California/Arizona border about 80 miles east of Imperial Valley.

But in the Valley, the lack of reliable water made agriculture impossible until the first canal was built in 1901.

(laid-back rhythmic music) Within 15 years, 300,000 acres were under cultivation.

(Alex) So, the Imperial Valley has the largest water rights, uh, on the Colorado River.

(Shane) The 1922 Colorado River Compact promises almost 30% of the Colorado River to California, and the Imperial Valley alone is entitled to more than two thirds of that water.

(Alex) It’s federal water, so, we get the water for free... -Okay.

-... and then, the cost of the water is the delivery.

(Shane) And the delivery price is cheap, because the All-American Canal is powered by gravity.

(Alex) That’s why we can buy water from our irrigation district for $20 an acre foot.

(Shane) Compare that with San Diego, where utilities buy water at $700 per acre foot or more.

But despite the Valley’s cheap water, Alex is preparing for an uncertain future by pushing the limits of water efficiency.

(Alex) It’s very fine-tuned, so, every six inches, we have an emitter, and each plant is getting drip, drip, drip, drip, drip, so, just super efficient.

(water spraying) (Shane) But water saved here doesn’t flow back to the Colorado.

The Valley’s irrigation district resells it at a profit to cities like San Diego.

This inequality is built into our current system of allocating water.

And if you ask Alex, recognizing those disparities can be hard when you benefit from them.

If you ask the person that-- that’s holding a cup of water, it’s pretty just.

If you talk to the person that has an empty glass of water, probably not so just.

How do you bridge that?

(somber music) (Shane) That’s the question that will define the future of the Colorado River and the 40 million people that rely on it.

♪ New rules governing who gets water and how much go into effect in 2026.

Exactly what those rules will be, well, that’s still to be determined.

♪ But the injustice of today’s system isn’t just about who has access to water.

It’s also about the collateral damage from how that water is used.

("Tequila Sunrise" by Cypress Hill) (Luis) It’s beautiful, huh?

It looks like we’re on the ocean.

(Shane) Yeah, it really does.

I feel like this is the kind of scene where you’d expect to see, like, beach umbrellas and beach towels and people splashing around in the water.

(barbecue-sound collage) This is Luis Olmedo.

(sizzling) When he isn’t making mouthwatering BBQ, his family’s secret recipe, Luis carries forward another of his father’s legacies, advocating for the people who call the Valley home.

♪ (Luis) My father was a farm worker.

Through a lot of the leadership lessons from the farm worker movement, organizations like Comite Civico were born.

(Shane) In the Imperial Valley, food is grown and harvested by thousands of migrant and seasonal workers.

And Luis’s nonprofit, Comite Civico del Valle, works to advance these workers’ rights and protections.

But there’s another issue that looms large here.

(Luis) Yeah, this, uh, this looks like the Gulf of California.

It’s just peaceful, like, it reminds me of that.

(newsreel announcer) Here in the desert, the new recreational capital of the world.

(Shane) Once known as the California Riviera, the Salton Sea boasted an inland coastline thronged by beachgoers.

Its idyllic shores drew celebrities like Frank Sinatra and The Beach Boys, and more tourists than Yosemite.

But this desert paradise... (ominous rumble) ...was a mirage.

(haunting music) (Luis) Over a hundred years of materials, chemicals, pesticides.

You know, anything that is being used by the agriculture industry, every time we flush our toilets, all water ends up in the Salton Sea.

Some of it treated, some of it not treated.

(Shane) It seems like a regular beach, but then, when you get close, you look at... like, the sand doesn’t look quite right.

The smell isn’t quite right, and then, of course, there’s, like, nobody.

By some accounts, the Salton Sea is an "accident" of infrastructure, formed when floodwaters breached a canal in 1905 and flooded an existing sump, or low point in the landscape.

(slide carousel-like click) But others argue that the Salton Sump was always the intended destination for agricultural runoff.

(Luis) I can’t think that the top engineers, top scientists, top geologists, top agronomists of their time, and investors of their time, made a mistake, and somehow, the Salton Sea became a sump for agriculture.

(waves softly breaking) (Shane) Whatever the engineers’ intent was, the Salton Sea has become something else.

(uneasy music) With no outlet to the ocean, its shallow waters evaporate into the desert air, concentrating mineral salts, fertilizers, and other agrochemicals.

♪ As water use in the valley dwindles, the lake is shrinking and exposing toxic sediments left behind by decades of runoff.

♪ And in the Valley’s notorious winds, those sediments take to the sky.

(gauge’s blades whirring) (soft, tense music) Data from these stations have prompted Luis and colleagues to sound the alarm on some concerning trends.

The rate of pediatric asthma here is among the highest in the U.S. (faint traffic noises) ♪ (Luis) People are being assaulted persistently by toxic particulates that are attacking their bodies, their lungs, the cardiovascular system.

(Shane) People living near the Salton Sea also experienced the highest death rate in California from COVID-19.

(Luis) This is a health crisis.

This is an environmental crisis.

(birds calling) (Shane) Thousands of birds have died of avian cholera, and fish suffocate en masse in stifling, nutrient-clogged waters.

(Luis) And we live in the best country, you know, of the world.

That’s what we say, right?

-We believe that.

-Mm.

(Luis) But if we’re that, well, what happened here?

(sorrowful music) (Shane) The abandoned lakeshore, the putrid smell, the health disaster.

It’s apocalyptic.

♪ And it’s not the only place that our grand aspirations of taming the Colorado River have transformed.

♪ It’s still so difficult for us to, like, look beyond our immediate surroundings.

(echoing footsteps) And I think it’s not necessarily cognitive dissonance, but a disconnect of scale.

(whooshing) We only see what we use ourselves, but our demand is additive.

No one user can drain an entire river, but our combined thirst can.

Today, most of the Colorado River is diverted into concrete canals at the Imperial Dam near Yuma, Arizona.

But it once flowed uninhibited through Mexico to the sea.

Paddling the river delta in 1922, a young Aldo Leopold found that, "The river was everywhere and nowhere."

(dark hip-hop music) But today, the river is definitely nowhere.

(spare, sparse music) Mexico was left out of the 1922 Compact entirely, and a 1944 treaty committed just 1.5 million acre feet a year to Mexico, less than 10% of what flowed to the delta before Western settlement.

Today, the river, or what’s left of it, no longer reaches the sea at all.

♪ (dynamic music) (Shane) Is this a favorite dish of yours?

(Shane) Mm.

Mm.

Es delicioso.

Don Beto is one of the sharpest shots this side of Mexicali.

(gunshot) ("It’s the Delinquentes" by Delinquent Habits ft. Sen Dog) (gunshots) When he doesn’t have a can in his crosshairs, he’s aiming to keep his family on their ranch, which means finding new ways to live in an ever-more-arid landscape.

How long has your family been here?

(Shane) Historically, Don Beto’s family, like others here, grew cotton, wheat, and alfalfa.

But those crops need reliable water.

(Shane) But Don Beto isn’t giving up on this land.

♪ (Shane) He’s built living fences made of saltbush and nopal, with mesquite trees for shade.

The goal is to make food production and ecological restoration happen side by side.

So, sharing water is vital.

(spare, sparse music) (Shane) It isn’t just farms and communities in Mexicali that feel the loss of the river.

The "everywhere" river that Aldo Leopold explored a century ago also hosted millions of migrating birds and countless other species.

(birds honking and calling) (Aída) Imagine the Colorado River Delta a hundred years ago.

It was miles and miles of wetlands.

("Love" by Mos Def) ♪ I start to think ♪ ♪ And then I sink into the paper ♪ ♪ Like I was ink ♪ ♪ When I’m writin’, I’m trapped ♪ (Shane) Aída Navarro has a passion for writing.

So, for her, bringing diverse stakeholders together to revive the delta is like weaving together the threads of a great story.

(Aída) After the dams were built and after different decisions were made, this area dried out.

All these livelihoods that used to depend on the river, that used to swim in it, sail on it, and fish.

And next thing you know, there’s nothing, there’s desert, and there’s only water going through irrigation canals.

(mellow music) (Shane) I met Aída at the annual Raise the River event.

Ten years ago, people celebrated when a binational agreement between the U.S. and Mexico sent a pulse flow, a rush of over 100,000 acre feet of Colorado River water, into the delta for the first time in decades.

(Aída) When the water started flowing, it was just a frenzy of happiness and joy, and everyone came down to the river and started bathing in it and fishing.

That was our first grasp of how impactful this could be for the community.

(Shane) This year’s event, celebrating the anniversary of that pulse flow, took place at an ecological restoration site, where the comeback has been dramatic.

(gentle music) (Aída) The trees used to be very little.

If you now go there, you will see trees that are, I don’t know, 30 feet tall.

There are a few families of beavers.

It’s beautiful.

(Shane) Even that brief infusion of Colorado River water fueled a 16% increase in vegetation and rekindled hope that the delta could come back.

(Aída) It proves that we can turn things around.

There is hope for us to do things right.

(Shane) The rare places where water does make it into the delta provide a glimpse of what could still be.

(wondrous music) (Shane) Juan and Alex are my guides to La Cienega de Santa Clara, a now-critical wetland that, much like the Salton Sea, was created by accident, growing and shrinking with agricultural runoff from fields in California.

(geese honking) (Shane) Today, in the otherwise arid delta, La Cienega hosts hundreds of thousands of migratory birds.

(somber music) (Shane) We move a lot of things around.

We move entire rivers.

And I think, as you move down the Colorado, you see that pretty blatantly.

♪ We can turn deserts into oases, but we can also turn oases into deserts.

The forces we’ve unleashed to bend this river to our will seem so much bigger than the humans working to restore it.

But people built those dams and canals, and people can build a movement, too.

What was so exciting to you about this project?

The fact that it seemed impossible to bring water and life back to the Colorado River Delta.

And now, here we are.

(Shane) On the Colorado River, we did what people do best.

We saw a challenge, tapped into our limitless ingenuity, and built a solution.

But the nature of the fix, and whose interests it really serves, tell us more about ourselves than we’d like to admit.

♪ (Giulio) Water is not a technical, scientific, ecological issue.

It is fundamentally a political issue.

The landscape around us, it’s an image of us.

It’s the product of the sequence of choices that we made over centuries and millennia.

I suppose that water reminds us that citizenship is not just about rights.

It’s also about responsibilities to ourselves, to our neighbors, to our communities, and to the future.

(Shane) Today, the future of the Colorado River, and rivers everywhere, is in our hands.

Humanity’s demand for fresh water is growing, even as the supply dwindles.

♪ Can we use water more thoughtfully and share it more equitably?

Can we let rivers be rivers and instead, change ourselves?

♪ I really hope we can, because what this river taught me is that water is life, and to be water’s steward demands humility over hubris, for the sake of all who depend on it.

♪ (mellow hip-hop music) (female announcer) This program is available with PBS Passport and on Amazon Prime Video.

♪ ♪