Jeremy Wade's Mighty Rivers - Full Episode 5 - The Mississippi

Starting west of the Great Lakes and flowing down to the Gulf of Mexico, the Mississippi splits the US from top to bottom.

Control of the river was crucial to the outcome of the American Civil War and such [music] is its strategic and economic importance that keeping it safe for shipping is to this day the job of

the US Army.

Beneath the surface though, on multiple fronts, there are unseen threats to the life of the river, alien invaders,

toxic runoff, destruction of habitat.

And especially vulnerable to all this environmental pressure are three iconic river giants.

Is their retreat an early warning?

And is the Mississippi [music] heading for collapse?

I'm starting my investigation in the upper reaches of the Mississippi, where the Illinois state government is waging a multi-million dollar war against an

army of invaders known as Asian carp.

They are now swarming through the Mississippi system.

What I want to do is find out what's being done about it. I've come to meet veteran fisherman Captain Ron Brown.

He's going to take me to the eye of the storm.

You don't see it, Jeremy. Yeah, good

start.

Hopefully we see a few today.

Asian carp were first brought to America in the 1970s to help the fish farm industry in the south.

The vegetarian carp were intended to be an eco-friendly way of controlling algae in ponds.

But the plan backfired when floods allowed the fish to escape into the nearby Mississippi.

50 years later and 800 miles up river, the carp are out of control.

They don't jump 10 ft in the air. We had

Chinese people here they say they don't jump in China.

Fish jumping there. Oh, there you go.

Some over there. Oh, there they go. Over

there.

So, it doesn't take long to find the fish then, does it?

Ron and his bounty [music] hunters are paid by the day to take out the carp.

And the men are out here all year round.

We try to concentrate on where we get the most fish.

Is that going all right? Is that Yeah, you're doing fine.

The surface [music] is calm, but I'm told that in some spots the carp are so densely packed that the water is like fish soup.

Our job is to stir it up.

We scare them out.

Spooked by vibrations, the carp are prone to panicking.

If we can get them going, our nets should catch them as they try to bolt.

Thing of this pounding like this, you want to pace yourself. You don't want to wear yourself out in 10 minutes.

Yeah, yeah.

Steady slow, steady.

When Captain Brown [music] judges the moment is right, we ramp up the assault.

Oh, here we go. Here we go.

[music] Just turn on the fish. They're pretty

fast.

One more in the boat. Others landing in the net. One on my leg.

the net. One on my leg.

Beautiful day.

You almost done us a bother with the nets. You just drive around, make a

nets. You just drive around, make a noise, and they just jump in the boat.

Deadliest Catch, I think it's here.

I'm no fan of dead fish, but I'm aware that these carp are a serious threat to the river's ecosystem.

The man in charge of this mass removal operation is state official Kevin Irons.

And here we are battling a Chinese fish.

And Asian carp are great invaders.

Along some stretches of the river, Asian carp make up 95% of the biomass. They filter the water through these gill rakers, and they can

filter less than 20 microns. Very small.

That's like a particle of dust. That's

it. They suck up a lot of the plankton resources and algae that all the fish need. So, just by breathing, they're

need. So, just by breathing, they're feeding and growing.

That's right.

How are these affecting the uh native species?

Lowered numbers of the things that eat plankton, things like bigmouth buffalo and uh gizzard shad. So, we've seen those numbers sag. And what about the other species that aren't so directly competing with these? We've seen lower

populations of bass and other sport fish.

Does anything feed on these? They

quickly overgrow the mouth size of most of the predators here in the river. Even

the largest catfish would have a hard time with this fish here.

In the nightmare scenario, the aliens spread far enough up the Mississippi system to infiltrate the Great Lakes, where a multi-billion-dollar fishing industry is at stake.

We don't want to take a chance. So, we

have three electric barriers run by the US Army Corps of Engineers. We have

physical fences and several locks and dams between here and the Great Lakes.

Now, all those things are slowing down the spread. We're doing just about

the spread. We're doing just about everything we can to stop these fish.

So, the dead carp don't go to waste.

In Illinois alone, around 3,000 tons of problem fish have already been turned into high-grade farm fertilizer.

And according to Kevin, his men are just about managing to hold the line. We need

to win the war here. But stopping the carp is an extremely costly business.

And elsewhere, physical barriers appear to be having little effect.

Above St. Louis, 29 dams turn the Upper Mississippi into a giant staircase.

To find out if the carp have reached the [music] top, I'm heading north.

You might think a big dam would stop the carp in their [music] tracks. But each

time a ship travels upstream past one of these barriers, it does so via a lock, which fills with river water.

In theory, it only takes one or two carp to slip into a lock along with a ship, and hey presto, the aliens can start to overrun the next stretch of river.

Today is a very special day for me. I'm

going fishing for the smallest thing that I've ever been after.

And I actually hope that I don't get it.

I'm in the heart of Minneapolis, wondering if the invading carp have already snuck past the Mississippi's last dam.

But it's no use testing the water with my usual hook and line, as the vegetarian carp don't take bait.

I'm not fishing for whole fish. I'm

fishing for DNA, which will be packaged up in fish cells floating around in the water. Because fish, like us, they tend

water. Because fish, like us, they tend to lose cells just during the course of everyday life.

There's a filter in that nozzle that will catch individual cells.

This is the world's first portable device that can detect and quantify DNA in river water.

A positive result would be the worst possible news.

Let's just have a quick peek at what we've caught here.

All right, that's the gunk that we've filtered from the river water. Normally, this

would be sent off to a lab and if you're lucky, you get the results back in a week. What's special about this setup is

week. What's special about this setup is that I can actually analyze this straight away.

While I wait for my samples to process, I hook up with state biologist Nick Frohnauer. How important is it to the

Frohnauer. How important is it to the health of the river that you keep out the Asian carp?

It's very important. They have the potential to really affect the whole aquatic community. When you have this

aquatic community. When you have this big fish that comes in that can eat almost its its weight in food a day, that's really taxing on the system as a whole. Secondly, they jump out of the

whole. Secondly, they jump out of the water. So, you have the human safety

water. So, you have the human safety factor. They can cause serious injury.

factor. They can cause serious injury.

Nick tells me that if Asian carp overrun this stretch of the Mississippi, [music] they'd also do serious harm to an angling industry worth billions of dollars.

I've barely registered this economic threat when my DNA results are in.

Perfect. The samples that you took today are negative. Flatline. [music] That's

are negative. Flatline. [music] That's

good. It's very good.

[laughter] So, flatlining is good in this case?

Yep. It means there's no DNA in that water sample. So, what that shows

water sample. So, what that shows basically is that this is still a good uninvited stretch of river. Yes.

Although welcome, my result is also puzzling.

For more than a decade, there have been sporadic reports of Asian carp just downstream from here.

And yet for some reason, the aliens have failed to reach [music] the water above.

The picture with Asian carp seems to be getting more complicated the more I look into it. There is this

into it. There is this [music] perception that they are just this marauding army. Wherever they get a

marauding army. Wherever they get a toehold, they just explode.

But it turns out that there are places where they are present, but they [music] haven't exploded.

Why is that?

60 mi downstream near the Iowa border, the Mississippi widens to nearly 2 mi across.

Superficially, this stretch of water is no different from the carp infested river I saw in Illinois.

And yet for 15 years, it has defied alien takeover.

Hoping to discover its secret, I'm going fishing with a man who grew up in this neck of the woods. Let's do it.

John Hoxmeier is a scientist with a special interest in tracking some of the Mississippi's rarest fish.

I grew up fishing in Minnesota my whole life. It's so neat to be working on the

life. It's so neat to be working on the Mississippi River.

That's a big area of water, isn't it?

Absolutely.

The fish that we've got tagged out here now, they're moving hundreds of miles.

They'll swim from the bottom of the lake up to the top, which is 22 mi in 2 days.

And so, you don't know where in this circle they're going to be.

While John and I head out to his nearest net, a second team has gone to check two other fishing sites. Is that it over there? Yes, that's it.

there? Yes, that's it.

Let's see what we got.

It's 24-ft deep.

It's a 6-in mesh. So, you don't get a lot of fish, but what you do get is memorable.

Many native fish are plankton feeders, just like the alien carp, which first showed up here in 2003.

So, are the Asian carp having any impact here?

We don't see a lot of Asian carp up here. They would have an impact,

here. They would have an impact, but we just don't see the numbers here.

Yeah.

But, the Asian carp are definitely here, but they just They're here. They haven't

exploded as they have in exploded like they have further down south.

Given the good habitat that we have up here, there's a lot of resistance built into the system. Wow. And so, there's just not a lot of room for an invasive fish.

So, are you saying that the Asian carp need a vulnerability, a gap that they can exploit? Exactly.

can exploit? Exactly.

If John is right, the carp are much more likely to take over where the river is already in bad shape.

Oh.

There's definitely something here.

There's something here.

Feel something? Yeah, I felt a pull.

Can you see it yet? Uh

Just feel it.

There it is.

Oh, yeah. That's a nice one.

It's a hefty fish.

You can get his tail.

But, not what I was expecting. Oh, oh.

Oh ready?

Here we go.

I'm here.

That's it.

Ooh.

So, what we've What we is a lake sturgeon.

That's a beauty.

I'm guessing 50 lbs.

I would say so. [snorts]

Lake sturgeon can grow to 7 ft in length and top out at over 240 lbs. [music]

But these fish take more than 10 years to reach maturity and are slow to reproduce.

Telescopic mouth.

And in front of the mouth you've got these feelers for tasting and its vibration.

Oops.

Woah.

Ready? There we go.

Still got some energy? Yes, it does. I

think it's in good shape. We can put a transmitter in this one.

A transmitter will help John to piece together the sturgeon's movements.

Of crucial importance is to identify and protect its breeding sites.

We still have a lot of intact habitat.

We have a lot of backwaters, side channels, which gives us a really diverse fish community.

We have 87 fish species here.

Installing the transmitter requires some light surgery. The reason this towel is

light surgery. The reason this towel is here, this is a fish that lives quite deep in the water, so coming up into the daylight is a bit of a shock to the system. So this is keeping it nice and

system. So this is keeping it nice and dark and we flipped it on its back. It's

a state called tonic immobility. Put

them on their back and they sort of go nice and calm. We don't want the fish thrashing around when John's doing surgery.

So a bit of iodine going on.

It's like football leather.

This tag is going to give out a signal every 2 minutes for the next 10 years.

They can live to be 100 years old.

You need these tags that can at least follow a significant part of their lifespan.

[music] So far, what have the results shown you?

These fish need long open stretches of river.

One of their big impediments is locks and dams. We want to make sure that any barrier we put in for Asian carp doesn't affect our native fish movement.

We still don't know how far these creatures are moving up and down the Mississippi.

But John's tags point to journeys of hundreds of miles.

All right, let's just have a good look at this out of the water.

[music] Oh.

Ah.

Strong and healthy.

What a great size.

This hefty 10-year-old sturgeon is a very tangible sign of a healthy river.

[music] We've barely released it though when the second team arrives back.

And it looks like they've got something even more spectacular.

I really can't wait to see this.

This is from beyond the time of the dinosaurs.

There are fossils 50 million years before dinosaurs even appeared.

So this is a very, very special fish.

The American paddlefish gets its name from its bizarre snout.

Packed with electroreceptors, this high-tech protrusion enables the fish to detect even a single speck of plankton in murky water.

Oh, it's heavy.

Heavy.

First time I've ever held one.

Even though they've been around such a long time, there's a lot we still don't know about these fish.

This tag is going to fill in some of the gaps.

With a bit of luck, these will be around for another 400 million years.

This part of the Mississippi has been a real eye-opener.

In the same way that a healthy body can fight off infection, it seems that a healthy river can pretty much look after itself.

So, a resistant river needs its native fish.

But, I've seen worrying reports that the Mississippi's backwaters, the very places [music] where lots of its fish like to breed, are turning into death traps.

Still in Minnesota, [music] I'm going to get my first glimpse of a growing and occasionally lethal menace.

Those waters are having a problem with massive algae blooms. They can be quite dangerous. Algae are plant-like

dangerous. Algae are plant-like organisms that are usually harmless, but which in excess can be deadly. Yes,

2014, Toledo actually had to shut down the water supply to a city of 500,000 people because of an algae bloom that was toxic.

My pilot, Dave Nelson, grew up on the Mississippi. Now retired, he's a man on

Mississippi. Now retired, he's a man on a mission. What I'm trying to do is take

a mission. What I'm trying to do is take aerial pictures that will show when the algae blooms are happening, and correlate [music] that to temperature, rainfall, and other factors

that could be causing the algae to be a problem.

Sometimes the algae is toxic, but it's very difficult to tell.

Even in tiny amounts, some algal toxins can cause vomiting and diarrhea in humans. Take a look to the right. Oh,

humans. Take a look to the right. Oh,

yes. My bird's-eye view is giving me a real sense of the scale of the problem.

It's just so clear from up here.

I can hardly believe what I'm seeing, the extent of the algal blooms. Mostly in the back channels, but also in the main river. And this isn't even the high

main river. And this isn't even the high summer when the problem is at its worst.

The backwaters are often just solid green. Looks like you could walk on

green. Looks like you could walk on them.

Flying with a purpose, is that important to you? It's very important to me

to you? It's very important to me because as we mess with our ecology, we mess with our future.

To find out how the blooms are affecting the Mississippi's fish, I need to get into the backwaters.

Hi Megan. Jeremy. You good to go? Yeah?

I'll get myself kitted up.

All ready? Yeah.

Biologist Megan Moore has been monitoring the backwaters here for the last 20 years.

And she says [music] the algae problem is getting worse.

We have to travel by airboat since the submerged propeller of a conventional boat would quickly get fouled in all the floating muck.

Wow. That's a huge problem in our backyard.

It looks pretty choked in here, but this bright green stuff we're seeing on the surface, that's not the filamentous stuff, is it?

No, that's duckweed. [music] There's a couple species of duckweed, but that's natural native area.

And those are the little leaves that float free, and Exactly, yep.

Normally we use a rake to pull up the aquatic plants and look what's here.

Okay. I would quite like to get a close look at this.

Help him.

Oh, it's not too bad.

This is interesting. [music] It's not breaking the surface, but as soon as you look down, it is just solid.

Ooh, I can hardly lift it.

This type of algae isn't the toxic stuff, but it's just as deadly. It's

green, isn't it? Most people think that green is good, is healthy. So, I mean, what really is wrong with having too much greenery in the water? Green means

it's photosynthesizing, using the light to create oxygen.

It's doing that during the daytime, but at night it can't photosynthesize anymore. That means it's consuming

anymore. That means it's consuming oxygen rather than creating oxygen. And

that's going to be a problem for the fish. It's a big problem for the fish.

fish. It's a big problem for the fish.

Areas like this are really productive nurseries for the small fish. This is

where they want to go for protection.

It's a safe harbor, but at night, when the oxygen is depleted, that would basically suffocate them.

Put simply, too much algae is sucking the life out of these backwaters.

And the nutrients that are fueling this algal growth are anything but natural. A

lot of excess [music] nutrients comes in from agricultural areas. That's where we apply a lot of our nutrient, and they wash us down and comes into the river.

So, fertilizers? Fertilizers.

It's being tipped on the land, and a lot of it is not fertilizing what it's supposed to fertilize, and it comes down here and is is fertilizing It's really a waste honestly.

Just 3 months ago, neighboring Wisconsin suffered its worst algal bloom in over 20 years.

And with the nutrient [music] pollution flowing all the way down to the Gulf of Mexico, I'm wondering if anyone has a fix.

In the heart of America's corn belt, I've heard about some farmers who could be sowing the seeds of a revolution.

Greg Langer has been farming here for 25 years. We realize now that there was

years. We realize now that there was some mistakes made over the years, and we want to contribute towards the river getting cleaned up. So, we're using considerably less fertilizer than we did

10 years ago. Is that to the same effect, more or less? We're actually

getting uh better yields [music] than we were getting before.

Smart machinery is now helping farmers to apply nutrients much [music] more precisely, which means they can use less fertilizer to grow more corn.

But just as important for the Mississippi is a surprisingly low-tech remedy.

You've got this grass strip. What's that

about?

When when we get two, three, [music] four, five inch rain, this whole area here will be under water.

These are very effective in filtering out [music] excess fertilizer, excess chemicals.

So, in the past, the way we farmed it, that just all washed down into [music] what became a creek that flowed into the Mississippi River.

By planting drainage channels with grass rather than crops, much less of Greg's fertilizer is washing into the river system.

Is this something that's catching on and does word spread? It does, yeah. Farmers

talk to each other. It's a lot easier to start controlling it here. Every land

owner were to do a little bit, uh great things would happen.

So far on the Mississippi, I've seen a worrying army of alien invaders.

But I've also found two of the river's native giants.

And as I travel south, I'm wondering about a third and equally spectacular fish.

Huge and bristling with teeth, the alligator gar is a potentially useful ally in the war against invading carp.

Unfortunately though, these unloved predators have been largely wiped out from their old haunts along the Mississippi.

South of St. Louis, I'm heading [music] to one of the last reported refuges of the alligator gar on the Mississippi.

I want to see for myself if it's still here.

This is a really significant species.

There's nothing else like it anywhere else in the world, but most of the habitat that it used to occupy, backwaters like this, have just gone.

[music] The presence of gar would be encouraging news.

But as I'm not aware of anyone here who studies them, I'm on my own.

For bait, I'm trying Asian carp.

And to boost my chances, I'm putting out three lines.

Yeah, it's moving. It's moving. It's

moving.

Quite close. Quite close.

Yes.

Hold him up in the water and I'll draw it at the top.

We've got a gar.

Fantastic.

Look at that.

Alligator gar from the Mississippi.

Caught on a piece of Asian carp.

What a fantastic sight.

Alligator gar are known to prey on young carp, taking them out before they reach breeding age.

[music] This is something that was contemporary with the dinosaurs.

And they're still here.

The fact that I found this in the Mississippi is hugely significant.

[music] They may be making a comeback.

I'm pleased to discover that I'm not the only person here who's rooting [music] for alligator gar.

A few inquiries lead me to a man called [music] Chris Kennedy. I'm doing great.

How are you? Who joined the Missouri Department of Conservation in order [music] to fulfill a childhood dream.

It took me 7 years just to get permission from my agency.

So, it did not come easy.

Chris has persuaded his department to restock some of Missouri's backwaters with alligator gar.

The unreasonable disdain for the species is is really evident. It still is today.

So far, Chris and his team have released over 4,000 of these predators into the Mississippi.

That's That's That's a lively fish, isn't it? Yes. That's a good thing.

isn't it? Yes. That's a good thing.

Jeremy, this is my [music] favorite part.

After so much work and so many written justifications, it's nice to be [music] able to put this fish in the water.

This is what it's all about.

I'd say that's a healthy fish.

Very healthy fish.

We've got issues in our big river with Asian carp. [music] We need to really

Asian carp. [music] We need to really see if our alligator gar can begin to resolve some of those issues. And in

order to do that, we need that population [music] to build. That means

that anglers that do happen to catch alligator gar in Missouri, I would really encourage them to let them go at this stage. [music]

This is a awesome privilege to be able to reintroduce a a species back to the state [music] of Missouri. It was not here.

Shallow backwaters provide crucial breeding habitat for the gar.

So, it's good to know that Chris's department is also bringing back some of the Mississippi's ancient swamps.

Further south, in Louisiana, I've heard about a very different plan to tackle the Asian invaders.

There's actually a guy here who likes his carp big. So, I'm bringing him For what? a gift. I've got a present for

For what? a gift. I've got a present for you. I've heard you're the man to deal

you. I've heard you're the man to deal with this.

A chef by training, Philippe Parola moved here 20 years ago [music] from his native France.

To beat the carp, he wants to [music] recruit American consumers.

That meat is really nice.

Oh, yeah, it's very nice.

Philippe, however, has identified a problem. [music]

problem. [music] I want you to cut it and see the bone. You have to go hard. Can you

the bone. You have to go hard. Can you

feel the bone? I can hear them. You hear

it? It's the cracking of it. That alone

is the biggest problem to overcome with this fish because here we like the fish without bones.

Is this ready to go? Yeah.

In time-honored fashion, a product with an image problem has been rebranded.

In this case, as silverfin.

This is the fried silverfin. Take a

piece. Go ahead.

That's really nice. Huh? It's really

good.

So, imagine that fish [music] with no bones.

We will have no problem. Yeah.

It's sort of hard work. It's a bit like oranges, you know, you I love oranges, but it's a lot of work getting an orange without, you know, you get sprayed in the face, you got to go and wash your hands.

It's a bit like that.

Fortunately, though, Philippe has developed his own secret process to remove the bones.

Here you go, Jeremy. The solution to the Asian carp.

I don't know. That's nice.

[music] The taste is fantastic.

I am impressed by the lack of bones. So,

you've got You know, I don't want to ask the secret, but you have successfully cracked that problem.

We won't eradicate the fish for sure, but I think we can control the population. This is the only way we have

population. This is the only way we have to be able to save our ecosystem, our fisheries.

Eat the problem away.

It's a win-win situation.

In my investigation so far, I've met plenty of people who care about the Mississippi.

[music] But where are all the people who once lived off this river?

And what is their absence telling me?

[music] South of Baton Rouge, I think I've finally sniffed out the last of a dying breed.

How you doing? I'm very well, thank you.

Good morning. Yes, [music] sir. It's a

gorgeous day again, isn't it? Boyboy and

his nephew Jay are shrimpers and proud to call themselves Cajun. I've been here all my life, living right here.

And uh I I do I I get everything I can out this river when I can.

How long has this been out there? Three

days.

Are there many people doing this now?

I would figure there's me, my nephew, one man about a mile further that way.

I don't know anybody from here to New Orleans, 50 miles on this side, that would say there's probably a four of us.

Boyboy tells me that not long ago, there were thousands of people catching shrimp up and down the river. I don't know what happened, but uh people quit doing it

because they weren't catching as much.

Time changed.

I'm just looking at all this industry.

When you grew up, was this here?

No, no. That was one ship a month. I

used to cross the the river with a canoe, back and forth.

Catching shrimp on the other side.

I didn't have to worry about a boat.

If I do it now, I I'd get hit. There's

so many that pass here.

What about the next generation down? Are

they No, no, no, no. It's over. Yeah? We

we're the last of it. Now, I wouldn't think that we're the last.

I've heard of Louisiana shrimp gumbo, but I'm a little surprised when Bo Boy invites me to try one right out of the trap.

You can eat them now, yeah? They're all

good.

You hold the head back like this.

Delicious.

Sorry shrimp.

Put it in your mouth, clean pull.

Sweet sweet sweet.

That's nice.

It's all right. First one I've eaten like that.

I got to say, Bo Boy, For a creature this [music] small, these guys have a pretty amazing story. They

travel so far. Their migration is a thousand miles.

These shrimp start out near Ohio and they migrate all the way down to the salt water estuaries. But Bo Boy's shrimp catch is declining and I wonder if this is linked to the taming of the

Mississippi.

To make shipping more efficient, large sections of the river have been straightened, which makes the water run faster.

If you're a tiny shrimp trying to reach your breeding ground, a stronger current is seriously bad news.

Just as worrying, [music] though, is what's actually in the current.

For nearly 50 years, America's Clean Water Act has helped protect the Mississippi from industrial pollution.

But poke around along the banks and you'll find plenty of domestic waste.

[music] Now, a bottle like this is going to make the place untidy for years, but the real problem comes when plastic has been out in the sun and the weather for

a long time. It becomes brittle and then it breaks down into smaller and smaller pieces right down to invisibility.

Everyone knows there's a huge problem with plastic in the oceans.

But what about rivers?

To find out if plastic is harming the Mississippi, I've arranged to go fishing with Professor Mark Benfield of Louisiana State University.

[music] For the past 3 years, Mark has been sifting trash from the lower reaches of the river.

Our hunting ground today is a few miles downstream of New Orleans.

So we're just going across the river, is that right? Yeah, at each of our

that right? Yeah, at each of our stations, we do four net tows and each net tow is one transect across the river. So we'll go across from the west

river. So we'll go across from the west bank to the east bank, recover the net, wash it down and take that sample.

We keep an eye on what's coming downstream.

What's coming upstream as well. You need

eyes in the back of your head.

So there's a very fine net in there.

What are we fishing for exactly?

So we're going for small game. We're

going for microplastics, anything 5 mm or smaller.

When we're sampling up in Baton Rouge, we're primarily getting fragments of plastic, residues of food to-go containers and Styrofoam cups, things like that. Down here, we see more

like that. Down here, we see more industrial plastics.

Well, I I guess the water all comes from much further away, so some of what you're catching here is as got into the river a long way upstream.

Yeah, absolutely. A cup that gets tossed into the river in Minneapolis almost certainly is down here. I'd love to know the provenance of this plastic, you know, where did this piece come from?

Cuz there will be a story, yeah, somebody's sitting down for breakfast and it goes in a it goes in a can and that's the last they ever think of it.

Or a guy's trimming the his lawn with a weed whacker cord, you know, you start out with a spool of 50 ft of that stuff and it all disappears. But it rains,

gets washed off his lawn, into the sewers, and into the Mississippi River.

We are looking at the plastic refuse from 100 million people in the drainage basin passing through here and going into the Gulf of Mexico.

It takes about 3 months for water at the top of the Mississippi to get here.

And I'm curious to see exactly what's coming down in the current.

I can see stuff.

Using clean, uncontaminated water, research associate Dr. Matt Kupchik rinses our haul.

What's that? Yeah, so that looks like a piece of Yeah, it's a piece of monofilament.

Really, really thin fishing line is what it looks like.

And then the actual plastic sheet is very obvious, isn't it? Bottle water.

Bottle water, yeah, spring water. So

this is a brand from Arkansas and you can see it's fragmenting, it's already getting brittle.

Look at this.

That's a piece of insulation foam. That

foam with a piece of on either side.

That's just one piece of it. Here's

something blue. Yeah. Little fragment.

This this is just the obvious stuff, right?

Yeah, piece of Mark tells me that only a tenth of plastic particles in the river are visible to the naked eye.

What I'm seeing is just the tip of the iceberg.

If you multiply the tiny amount of water that we sampled by the volume of this river that's passing by us right now, we're talking about hundreds of

thousands of particles every minute that's passing through here.

There's an enormous quantity of plastic that's being pushed down the river from all the cities and towns upstream. It's

invisible, but this is a river of plastic.

And why is it a problem?

Well, plastic in itself is relatively inert, but the more insidious problem with plastic is that it acts like a sponge.

All those organic pollutants from pesticides, from herbicides, from industrial waste, they stick to the plastic.

So, what we have are millions of tiny sponges, each loaded with organic pollutants.

Mark explains that fish end up eating a lot of the plastic because algae growing on the particles smell and taste just like their natural food.

All right. So, it gets into fish, but somebody way up the Mississippi, why should they be concerned?

Well, there's a huge fishery in the Gulf for a a species of fish called Gulf menhaden. What they do is they take the

menhaden. What they do is they take the menhaden and they grind them up and they press them into cakes and they make poultry food and they make uh food for pigs and livestock. And so,

those chemicals are making a round trip.

They go into the Gulf of Mexico, into the menhaden, get processed, and then they get sent back into the heart of America to feed our pigs and our chickens. Which we feed

on. And and some of some of those

on. And and some of some of those some of those chemicals you mentioned are sort of hitching a ride. I mean,

they're known carcinogens. Yeah.

So, what the plastic is doing, it's it's actually concentrating all the bad stuff that's in the water and and then delivering it back to us. Yes, exactly.

[music] Nobody sees this. They look out and they see the river and they see water, but they don't see the cargo.

The billions of particles that are flowing through here into the Gulf of Mexico.

This is a real problem.

What can be done about this?

Well, we got to stop the plastic getting into the river.

Once it's in the river, it's too late.

And I think that really needs a change in human behavior.

We don't need to drink out of soda straws. They're a huge source of plastic

straws. They're a huge source of plastic waste.

When you go to the grocery store, take a reusable shopping bag.

Get a stainless steel water bottle.

Those are three things that are really easy.

One thing I've noticed heading downstream [music] is the huge and growing volume of commercial traffic.

Every year around a hundred billion dollars worth of goods flows up and down the Mississippi.

And to keep this highway fit for purpose, the river has been massively re-engineered.

What's good for ships though can often be bad for the life of a river.

And down in the Delta, that could mean human life.

12 years ago, Hurricane Katrina ripped into New Orleans, destroying homes and leaving well over a thousand people dead.

Hurricanes can't be stopped, but experts believe that man-made changes to the Mississippi Delta are leaving people more exposed than ever.

Morning.

Rosina Philippe belongs to the Atakapa-Ishak, a tribe that's lived in this area for centuries.

How bad were you hit by Katrina here?

Katrina devastated this community.

Resources were very limited. It took a long time to rebuild.

We had to actually fight to reclaim our lives here.

Rosina says that the Mississippi always used to bring enough silt to maintain the land, which in turn supported swamps and forests.

But then came the Great Mississippi Flood of 1927, which left more than 700,000 people homeless.

To prevent a repeat, the federal government decided to contain the unruly river within a series of earth banks or levees.

When they leveed the river, then that sediment that used to come in, you know, with the floodwaters, it's been channeled to go somewhere else.

Ever since the delta has begun to die.

But starving the delta of silt was just the start.

When oil and gas were discovered here, engineers began cutting thousands of canals through the swamps for pipelines and ships.

The results [music] have been devastating.

A lot of the canals that were cut allowed salt water to intrude into these freshwater areas.

Salt water killed the roots and the trees died.

What you see are the bones of the forest, these skeletal remains of these huge oaks that used to be in this area.

Now that root system that would hold the land in place is no longer there.

With no roots to hold it together, a football field of land is being lost every [music] 2 hours.

In the last 80 years, some 2,000 square miles have gone.

And with the land goes a vital defense against hurricanes.

When storms come in, this is the first line of impact. So, next time there's a big storm, instead of absorbing the force of that storm, it's just straight there. It hits the levee, the levee's

there. It hits the levee, the levee's more likely to fail. This could impact people in New Orleans and and and further on up river.

The levees are okay, but there's nothing that man can build that [music] can guarantee we'll be safe from the forces of nature.

Can anything be done about it?

Absolutely.

A lot of these old canals they need to be filled in because they continue to be avenues, you know, for salt water to intrude.

It's important to maintain what's here and to replace what can be replaced.

Like so much else that I've seen on my journey, the story of the delta is a tale of unforeseen [music] consequences.

Here on the Mississippi, I've seen how even good intentions can end up damaging a river's health.

The river is a much more complex thing than we used to imagine.

It's actually a living system.

Now, we're starting to see the causes of the things that are going wrong and they're starting in some cases to address those causes.

But the signs are this may not be enough.

If you take a river's health for granted, it dies.

And to prevent that happening to this vitally important river, I think it urgently needs a more concerted and joined-up approach.

This river, the Mississippi, has given so much to the nation of America, surely it's the least that it deserves in return.