- [David] The lower Grand Canyon is a rather narrow gorge.

From time to time aside canyons, Many of them excruciatingly narrow, empty into the canyon from both sides, with names like Elves Chasm, Deer Creek, and Havasu Canyon.

(gentle music) Each has a remarkable story to tell and leaves its mark on the river.

- [Announcer] Funding for "In the Americas with David Yetman" was provided by Agnese Haury.

Funding for "In the Americas with David Yetman" was also provided by the Guilford Fund.

(bright music) - [David] Many trips through the Grand Canyon begin at Phantom Ranch and end 192 miles downstream at Lake Mead, which was created by Hoover Dam.

The canyon here is a dark rock that is ancient by geological standards, except where the gorge was filled in more recent times by volcanoes that spewed incalculable volumes of lava into the gorge.

Boating is rather different now from what the hardened adventurers experienced before the river was tamed by Glen Canyon Dam more than a hundred miles upstream.

They were a hardy bunch.

- Oh, we're just about to drop into Horn Creek Rapid, which is one of the steepest rapids on the river.

There is some big white water in here.

- [David] My friend Tillie Walton spent years as a river guide in the canyon.

She is also a professional hydrologist who combines science with history and culture.

- So this is one of the restoration sites, over here on the left, where the nice cottonwood trees are.

There would've normally been cottonwoods on the river, it's one of the native plants, but the invasive tamarisk has taken over.

And so this was an effort by a lot of different groups to remove some of the tamarisk, which is sort of the big bushy stuff, and replant the native cottonwoods, which are kind of the taller, bigger trees.

- [David] These falls down here have gem-like names.

- We're still in the granite gorge and so we go, we start with Crystal and then we'll have Turquoise, Agate, Ruby and Sapphire.

- [David] It's a little weird to see on a boat sitting 50 feet above the river up, chained to a bunch of rocks.

- It is, this boat was from a film trip gone awry in 1915 and- - 1915?

- 1915.

And so one of the early prospectors down here drug it up on shore because he thought it might be useful at some other point.

And then they hiked out the Bass Trail, which was at the time a tourist operation and an asbestos mine.

It's in pretty good shape for a 100 year old boat.

(lively banjo music) - [David] As I look up, until I see what's really a hazy day, I guess, or forest fire?

- Yeah, I think there's a forest fire.

Yeah, probably on the North Rim.

- And that smoke is settling down and kind of gives that kind of, it softens everything.

- All right, coming in the top, we've got this reactionary.

Try and use that to keep us straight.

And then right here off to our right's gonna be the hole and then a rock to the left.

And the motor's still on the boat, that's good.

So there was a little beach right at the bottom of that rapid and Richard Quartaroli, a river historian, thinks that that's where Powell camped, probably this night 150 years ago, here we are walking in his footsteps.

Every rapid has got a story.

And you hope it's not about you.

(laughing) Usually means that something went horribly wrong.

I think reading water is definitely an art form.

Where I usually start at the bottom of the rapid and look for where the water is leaving.

Most of the rapids are going to start with a nice, big green V, nice tongue coming in.

And if I can connect those dots, I'll start there and then after I kind of have an idea of where I want to end up and where I want to start, I'll look for any obstacles that are going to be in the way and try and figure out a way to make sure I minimize the chance of heading towards those obstacles.

- We're actually coming to a really magical spot called Elves Chasm.

The special thing about the springs down here, is that they're almost a contrast to kind of the desert life, they're rich oases of biodiversity.

And there's creatures that are only found at these springs and nowhere else in the world.

- The water here comes from far above and passes through limestone, which gives the beautiful color here to the pool.

But also when it hits a rock and evaporates, produces what's called travertine.

It makes a new kind of rock.

So that rock is far younger than the chasm here.

It's a result of eons of the water passing through the limestone up above.

I'm leaning back on what is called Elves Chasm Granite.

It is 1.8 billion years, it has been dated to that, which makes it the oldest rock by far in all of the Southwest and most of the West outside of the Rocky Mountains, a hundred million years older than the Vishnu schist, which is the basement ancient rock of the Grand Canyon.

Geologists call a rock that consists of rocks from other places that have been somehow cemented together, they call that conglomerate.

And this is an enormous example of a conglomerate formed by the passage of water through thousands and thousands of feet of limestone, submitting them together and then producing this enormous boulder.

(gentle music) 150 years ago, almost to the day, John Wesley Powell stood and looked where I am kneeling and saw this very old rock with a wavy lines, more or less vertical, reaching a point where above it was rock that was clearly horizontal.

And he looked at that and said, this is what I would call a unconformity.

He named it the Great Unconformity.

And since his time, geologists have been able to estimate the age of both of these layers.

This one is 1.7 billion years old.

This one is 505 million years old.

There is a gap of 1.2 billion years which we know nothing in here.

Everything that happened in that 1.2 billion years is vanished.

And that's why John Wesley Powell called this a Great Unconformity.

It just does not conform to a geological record.

- [Tillie] We are witnessing and walking through a billion years of missing time, of all this rock that was once here and once laid down and it's gone.

(rafters whooping) Well, this is an amazing example of what's called a slot canyon.

And a slot canyons just where the river, the water's carved out a very narrow S turn.

And what's really beautiful about a slot canyon is you can see how water naturally wants to meander back and forth.

And it makes some beautiful designs here and a couple of other places in the canyon.

- [David] Very often in those really narrow canyons the slots will undercut so that if you're in an undercut, you can't, you can look up and you can't see the sky.

- Oh yeah.

- They get that narrow.

- [Tillie] Yeah, they're they're not a place you want to be during the middle of a flash flood.

So this is one of the most fun side canyons to hike because it's kind of like being a little kid and it's a wonder land.

- [David] Yeah, it's not quite as straight forward as some places.

Fortunately, I got Ben here to provide me with logistical support.

- [Tillie] Yes.

- [David] My gosh, you promised a limestone slot canyon, I didn't imagine it was this great.

- This is a limestone slot canyon.

- [David] By definition.

- [Tillie] Yeah, look at the way the water has just carved through here.

- It winds and winds.

And above is the magnificent Redwall.

Muave.

- [Tillie] Muave.

- At the top of a layer, or maybe even at very top of the rim, a crack can appear and slowly rainwater would then, will either dissolve or erode very slowly.

And if there's any kind of crack that goes through, water will follow that.

But the power of gravity pulling it down means that it will get deeper rather than wider.

And here is one in limestone, which is one of the hardest of rocks, and the water has done exactly that.

It dissolves and erodes it's way down far more quickly than it widens, so we have a slot.

Sometimes we're in sandstone, rarely are they in limestone.

This Muave limestone deep in the depths of the canyon, some of the most interesting limestone I've ever seen.

- [Tillie] It's big.

And the biggest stuff is at the bottom.

- To be smashed.

(rafters whooping) Proposals to erect dams in the Grand Canyon seem to have faded into obscurity.

More ominous for guardians of the canyon are plans for building a development, especially along the South Rim, that would tap into the aquifer, that same water source that feeds the side creeks and waterfalls.

Once that water has gone, it will never return.

Also worrisome for canyon conservationists is expansion of uranium mines that they believe would pose threats of contamination of water and the land.

About 20 miles upstream from here an enormous amount of water comes out of a base of the Redwall limestone.

It's known as Havasu Creek.

- This is one of the most popular stops on the Colorado river.

Almost every single river trip stops here.

There's people that come down through the canyons, hiking in by mule.

The Havasu Tribe lived here, about, a little over 200 people come down and live on this beautiful blue water in the summer and migrate back up to the rim during the winter.

One of the issues facing the tribe up top is uranium mine.

If they start mining for uranium again in this canyon, if there's a spill, which has happened before, it would pollute the very waters that we're standing in right now, which is the drinking water for the tribe, which would essentially be cultural genocide.

And so preserving and protecting these waters, and this place is of utmost importance, and keeping uranium mining out of the Grand Canyon is really a critical issue.

This place is just magic.

It's a magical oasis in the desert.

Miraculously enough, we have this entire place to ourselves, which is virtually unheard of in all my years being down here.

That's the beauty of the desert and the canyon, is it's full of all these secret pockets of amazing beauty that doesn't exist anywhere else.

And John Wesley Powell said the only way you get to see it is by toiling through it.

And each time you come down and look at it, it's different.

And from every angle and every trip, it's always different.

- It's sacred.

You peel back all the layers of ourselves and you find this wonder and joy underneath.

And the canyon, I think brings that out in all of us.

(lively music) My favorite part is when you go down the rapid and there's that smooth green tongue of water right before it all goes crazy.

- We need this.

We need this connection to nature.

And where there's no internet, there's no phones - The Grand Canyon, it's like nothing you can really describe in words.

It's humbling, makes me feel alive, but also small.

The perspective that you get of millions of years of activity and just thinking about our short lives and how somewhat insignificant we are compared to this.

- It's grander than you can even imagine.

I think it's a gift from the almighty to remind us that we are a very small part of this planet and our calling is to take care of it.

- As we stopped in different places I began to understand why many of the native tribes, Hopi, Zuni, Navajo, Hualapai and others, call it very sacred.

And so, and it's very beautiful.

It's very inspiring to see this place.

And it has been transformative, the power of the river and also how nurturing it is to all the wildlife and the plants and animals that are down here.

These birds, big horn sheep are powerful.

And we saw the old bull teaching a the young bull how they become the leader of the clan.

- I went from being deathly afraid of rapids to, like I can do this without feeling really scared, to really enjoying it.

(rafters whooping) (lively music) It's just a conduit from one dam to another, for one water supply to another, but you come through it's, it's a special, magical place.

- You really understand the beauty of it.

The importance of it, to think about all of the politics surrounding this one stretch of river, it's actually kind of mind boggling.

- This river provides water for 40 million people, that is tremendous.

And produces food that many more eat and produces power that that many of us rely on and sustains the ecosystem here.

And so this is just an incredibly important water system for the southwestern United States and for Mexico as well.

- This is one of those places, you know, where you have 270 plus miles and, you know, a hundred plus rapids.

It's so big, it's so grand, it's so colorful.

It's ever changing.

You know, it's kind of the definition of a place that makes you feel small.

And that puts everything else in our lives into perspective.

- [Tillie] I think one of the most special things about being on the river is the relationships that we build and just how we come together.

We start off in our own individual roles and our own titles and then what happens is as we interact our veneer cracks.

And by the end of that, we become a family and a tribe and we make long lasting, lifelong friendships.

And that's part of the magic of the river is it allows a space where you can, you can shed who you are in the outside world and really just relate to people one-on-one.

And what happens with the relationships, the ripples, you just never know where they're gonna go.

And so that's part of, one of my favorite parts about being on the river and the river family.

(rafters whooping) The river is a great equalizer.

And out here, we're all the same.

(gentle music) - [David] That volcanic field is active.

- Vulcan's Anvil.

It is the volcanic neck, basically the taproot of a volcano.

the cinder cone's been eroded away by the river but you can see basalt dike in the sedentary layers here and another one passing through connected to this.

This would have been the tallest dam, about 2000 feet in elevation.

That that would have taken, we can estimate about 30 years to fill that reservoir, and it would have backed it up clear past Lees Ferry where we started.

- Way up into Utah.

- Up into Utah, yeah.

So everything we've been in would have gone down.

Now, as that fills up, compromises the integrity of the dam, knickpoint headward erosion, foot erosion, catastrophic dam failure and massive flooding.

- 15 to 12 million years ago, all of a sudden the plate that was moving under the western United States was consumed, all of it.

And we get a new plate moving to the northwest, stretching things out, creating what we call Basin and Range.

And Nevada is a great example of Basin and Range.

The Sierra Nevada moves west, 200 miles of stretching between Salt Lake City and the Sierra Nevada, that's stretching.

But it produces a crack right here at the edge of their Colorado plateau.

And that crack somehow makes it possible for magma to reach the surface.

You've been here 50 times, I've only been here once before.

What do you see when you look down there?

- Some awesome, powerful water.

This is Lava Falls.

It is the biggest rapid on this stretch of river.

The desert scale goes from one to 10 and one is the easiest and 10 is the hardest, and this is a 10.

- Oh.

- We have this overview where we can see what's happening but as we come into the top, actually can't see the rapid.

At one place in particular where you don't want to end up in this rapid.

- [David] And where's that?

- That's called the ledge hole.

You can see we're on the horizon line and you can hardly even see what's going on below us.

- All I see is huge sprays of water coming up.

- Yeah, sprays of water coming up.

And we're on top a huge drop here.

(rafters whooping) This is good where he is.

And then he's gonna start powering this way 'cause it gets a little swirly through here.

And then, (rafters whooping) nice, and then here we go!

Yeah, here we go!

(all whooping and laughing) - This is called Pumpkin Spring.

The water originates up in some travertine.

The National Park Service warns the most toxic spring along the river.

You should not drink it, it's full of toxic metals, particularly cadmium and arsenic.

(relaxed banjo music) For most people who follow the Colorado river through the Grand Canyon, the takeout point is called Diamond Creek, it's named after Diamond Peak.

Probably 90% of the river runners get out there.

But for John Wesley Powell, it was another three or four days before they even came to where they could get out of the river.

Below I have never been, it's a new stretch for me and we'll wind up in Lake Mead.

(people whooping) After passing many miles through another outcrop of sedimentary rocks we're back down in the bowels of the canyon and the gneisses and the granites and the schists.

And when John Wesley Powell saw those he said his heart sank because he was sure they were entering into another area of huge rapids and waterfalls and they knew not what.

And they were almost out of food.

Their spirits were quite different from what the atmosphere is on this boat, kind of a frivolous, giggling atmosphere.

We know where we're going.

We have a very comfortable boat and we know that when we get out there going to be food and shelter and a very good feeling of comradeship.

Powell didn't have that luxury.

- [Ken] Here it comes, here it comes.

- [David] Diamond Creek to Lake Mead, and you'd been over many, many times.

- Yes and this is pretty amazing because we go back into the last granite gorge, so we're back into this old, old, old rock.

We've had such an amazing trip and the river, it ends in a lake, Lake Mead, which is made by Hoover Dam.

And so we'll get to the spot where the river actually ends.

(lively music) - The jet boat brought us a long way into Lake Mead from the edge of the Colorado Plateau and the Grand Canyon.

Now we see the mounds of silt, the hills of silt, left by the more than 100 years of accumulation here.

The Grand Canyon is behind us but the Colorado river continues to work at it, grinding away at the bottom, making the canyon ever deeper every day.

- Join us next time "In the Americas" with me, David Yetman.

The Colorado River provides the lifeblood of the southwestern United States.

It's a small river, but so vital to the region that without it, most of the 40 million residents would not, or could not be here.

The most contested part is between Hoover Dam, which has created Lake Mead, and the Mexican border.

Along that stretch the river has become, quite simply, a plumbing system.

♪ Deep river ♪ My home's in the Colorado ♪ Deep river ♪ I wanna cross over into lunch time ♪ That's all you get, Daniel.

(all laughing) (bright music) - [Announcer] Funding for "In the Americas with David Yetman" was provided by Agnese Haury.

Funding for "In the Americas with David Yetman" was also provided by the Guilford Fund.

Copies of this and other episodes of "In the Americas with David Yetman" are available from the Southwest Center.

To order call 1-800-937-8632.

Please mention the episode number and program title.

Please be sure to visit us at intheamericas.com or intheamericas.org.

(chiming music)