How We Got to Now (2014–…): Season 1, Episode 1 - Clean - full transcript

[ ♪♪♪ ]

Imagine if every time you took
a drink of water from the tap,

you were playing Russian
roulette with your life,

or the streets outside your door
were almost knee-deep in filth.

Well, that's what life was like
in the Western world

just a century and a half ago.

But over the next 100 years,
we managed to rid many cities

of this waste and disease.

So how did we get to be
so clean?

Well, it took guys like
the maverick railway engineer

who lifted a city to build
America's first sewers.



It's a crazy idea, but it's
also kind of a beautiful one.

And the doctor who added
potentially lethal chemicals

to the water supply of
an entire city.

These are classic examples
of the kind of people

who actually made
the modern world,

people you've probably
never heard of.

These were the hobbyists,
garage inventors,

and obsessive tinkerers,

ordinary people doing
extraordinary things.

The thing about these pioneers

is they didn't just make
our world a cleaner place,

they also set off an amazing
chain reaction of ideas.

The result were innovations

that would affect every aspect
of our lives,



from the world of high-tech
to fashion

law and order,
all the way to health.

I want to show how these
seemingly unconnected worlds

are linked by the unsung
heroes of clean.

I write about ideas
I'and innovation.n.

And this is the untold story
of How We Got to Now.

[ ♪♪♪ ]

How We Got to Now was made
possible in part by

the Corporation
for Public Broadcasting

and by contributions
to your PBS station from...

[ ♪♪♪ ]

You know, you look around,

today's city streets
are so clean

you could eat your dinner
off of them.

A city like San Francisco
spends $50 million a year

spraying and sweeping and
generally keeping the streets

free of filth.

But just a few feet below me,
there is a tide

of highly toxic waste.

This deeply unpleasant
river of filth

is one of the biggest
health issues

cities around the world face.

To see it requires
some serious safety gear,

a huge team of people...

There we go, okay.
Oh, yeah.

and nerves of steel.

Ironically,
the story of clean starts

in the dirtiest place
imaginable.

Another day, another sewer.

All right, here we go.
Okay.

I'm going in. I can already
smell it from here.

It's delightful, yeah.

All right, I'm going down.

[ ♪♪♪ ]

These are San Francisco's
sewers.

There's almost 1,000 miles
of these tunnels

that run beneath the city,
hidden from view.

Oh, this space is incredible.

It's really hot down here,
and the smell

is just kind of overwhelming.

And there are lots of little
critters walking along

on the sides.

This is... this is the
underbelly of the city.

I mean, in an incredible way,

like, this is what makes cities
possible

is this kind of space.

But we never see it,
we never experience it.

It's an extraordinary thing.

But what's even more remarkabe

is that many of San Francisco's
sewers were constructed

well over 100 years ago.

This old infrastructure
has now been expanded

as the city above has grown.

Which means it requires
regular maintenance

by people like Gene Chruszcz.

So where is all this waste --
this is pouring out

of someone's apartment building
right here?

This is a lateral going to
the apartment building.

So people taking showers,
washing their dishes,

going to the bathroom,
it all comes into this sewer.

And where is this flowing to?

This is all going to flow
to another big sewer,

and it goes to our
sanitary plant,

where it's treated.

Amazing.

The journey from homes to
wastewater treatment facilities

is only made possible

thanks to these amazing
century-old sewer lines.

This line was put in
in, I think, 1868.

- 1868?
- Yeah.

- The structure looks fantastic.
- Wow, that's amazing.

- That's incredible.
- Yeah.

Today, we take it for granted
that there's somewhere

for our waste to go
when we flush a toilet.

But just five generations ago,

there were no comprehensive
sewer networks

anywhere in America.

It meant that much of the filth
you see down here

was on the streets
and sidewalks.

You made a hard job easy.

Thanks. You guys done?
Ready to strip him?

Strip me!

[ chuckles ]

The history of clean streets
is surprisingly short.

As we rewind the clock,
you can rapidly see

our cities becoming
ever-dirtier places to live.

And nowhere is filthier
or more unpleasant

than mid-19th-century Chicago,

the place where the story
of clean in American cities

first begins.

[ ♪♪♪ ]

Back in the 19th century,

Chicago has a particular
problem

when it comes to keeping clea.

We think of horses as these
symbols of natural beauty,

but imagine what it was like
when all these cars were horses.

You take thousands of these
and put them on the streets

of an already crowded city
like Chicago,

things can get pretty grim.

Just imagine what this street
would've been like

150 years ago.

You're walking out in your
fine 19th-century outfit,

and the sidewalk is literally
lined with this.

I mean, it's an appalling mix
of human and animal excrement

that you have to wade through
on your way out to dinner.

The city is convinced that
the smell of this toxic waste

is causing the huge levels of
disease they're experiencing.

Something has to be done.

So Chicago hires this man,

engineering maverick
Ellis Chesbrough.

Chesbrough thinks he can rid
the city of its waste

by building the first
comprehensive sewer system

of any major American city.

But there's a problem.

Chicago is just too flat,

and that makes it
astronomically expensive

to build sewers underground.

But Chesbrough's got
an incredible idea.

If you can't dig down,
why not lift the city up?

And he's got the perfect
technology to do it:

the jackscrew.

The jackscrew
is a simple device

used largely on the railways

to lift trains on and off
the track.

But Chesbrough sees that
it could be put to use

in his sewer-building project.

If you can use a couple of these
to lift a locomotive,

why not use them to lift
a building or a block

or an entire neighborhood?

It's a crazy idea, but it's
also kind of a beautiful one.

Using railroad technology
to keep the city streets clean.

Starting in the 1850s,
building by building,

Chicago is lifted
by jackscrew

The spectacle draws crowds
of startled onlookers,

who watch on
as a city is lifted

right before their eyes.

[ cheers and applause ]

In 1868, one British visitor

watches a 22,000-ton hotel
be lifted.

This is what he had to say
about it:

"The people were in it all
the time, coming and going,

eating and sleeping,
the whole business of the hotel

proceeding
without interruption."

In 1860, engineers raised
an entire city block.

With superhuman effort, almost
an acre of five-story buildings

weighing an estimated
35,000 tons

were lifted by over 6,000
jackscrews.

[ crackling and crunching ]

As the jackscrews
did their work,

sewers were laid at the perfect
angle to drain.

[ water running ]

With the buildings lifted, new
foundations were built beneath

and raised streets and
sidewalks were installed.

But buildings weren't just
lifted in Chicago.

To make room for the sewers,
some got moved altogether.

We've got a great quote:

"Never a day passed during
my stay in the city

that I did not meet one or more
houses shifting their quarters.

Going out great Madison Street
in the horsecars,

we had to stop twice
to let houses get across."

I mean, there's a lot of traffic
in today's Chicago,

but at least you don't have
to worry about houses

going down the street
in front of you.

By lifting these buildings,

Ellis Chesbrough
was able to build

the first comprehensive
sewer network in America

and clean Chicago streets
of the muck and stench.

But the project was destined

to have some remarkable and
surprising consequences.

When you do something
as ambitious

as lifting an entire city,
it fires people up.

Chesbrough had proved that

even under the most difficult
circumstances,

sewers could be built.

Inspired by Chicago's example,
within three decades

20 American cities built
their own networks

of underground sewer tunnels.

[ ♪♪♪ ]

But building sewers is just
the beginning of a change

that will transform our plane.

With the muck off the streets,
attention soon turns to trash.

By 1914, over 70 cities
in America are providing

municipal refuse collection.

By the 1930s,
modern sanitation companies

are collecting garbage
for the first time...

and American cities are
becoming free of filth.

But Chesbrough and his sewers

do more than just
keep cities clean.

They prove that big
infrastructure is essential

for making cities function.

All around the world,

new underground building
projects are begun.

In 1863 in London,
the first steam train

travels under the city.

In Paris, the Metro opens
in 1900,

followed soon
by the New York subway.

Pedestrian walkways
and auto freeways,

followed by electrical highways
and fiber-optic networks,

are created around the world.

[ phone ringing
and electrical sparking ]

Today, whole parallel worlds
exist underground,

powering the cities above.

It's a revolution.

[ ♪♪♪ ]

Chesbrough's sewers
proved to be

an inspirational feat
of engineering.

But, unfortunately, they had
a bit of a teething problem.

The sewers were draining
into Lake Michigan,

which was the water supply
for the city.

Chesbrough may have made
the streets clean,

but the water was still
filthy.

And it wasn't long before
the problems became apparent.

In the 1870s, this was
a regular sight

in the bathrooms of Chicago.

The water was so filthy
with sewage

that it was regularly filled
with dead fish.

One observer reported
that the fish

would actually come out cooked,

and locals would refer
to their bathroom water

affectionately as "chowder."

As you might've guessed,
mixing raw sewage

with drinking water was not
such a good idea,

and not just because of
the dead fish or the smell.

The problem was the water
could kill you.

[ ♪♪♪ ]

But most of the Chicagoans
of the time

were blissfully unaware

that putting waste in drinking
water was so deadly.

No one could see
the hidden killers

that lurked in dirty water.

While Chesbrough's first sewers
let Chicago's waste

mix with its drinking water,

today Chicago does everything
it can

to keep the two separate.

I'm standing above
the latest addition

to Chicago's sewer network.

It's an epic project.

They've been working on it
for almost 40 years,

and it's cost nearly $4 billion.

But to understand the true scale
of this project,

I need to go stand in this
little yellow cage.

[ ♪♪♪ ]

Around five times a year,
heavy storms roll in

that can dump more than
7 billion gallons of water

on Chicago in just a few hour.

This causes the sewer network
first begun by Ellis Chesbrough

to overflow.

With nowhere to go, this
mixture of rainwater and sewage

can spill out
into people's homes

and pollute the waterways,
causing huge problems.

This network of tunnels are
designed to store and transport

this huge influx of dirty water
and keep the city clean.

Hidden from view, this space

will keep millions
of peoe safe.

Now, this is like a cathedral.

This is like the church
of engineering right here.

Look how immense this is.

This huge project has over
500 people working on it,

and Kevin Fitzpatrick is one
of the project managers.

This looks like the set of
a science-fiction film, right?

I mean, this is an amazing
space to work in.

Sort of the air
makes it feel like

you're on a science-fiction
set here.

We're about 300 feet
underground,

and it's always cool
and damp here,

so you get a little bit
of steam coming.

In a big storm, how much water
would be in this space?

This thing would be
completely full.

Be completely full.

Polluted stormwater would be
coming through that tunnel,

dropping right down here

and shooting out
into the reservoir.

But during a major storm,
so much water falls

that even these vast tunnels
are not big enough to hold it.

So an even bigger space
is required

to deal with all the water.

So here we go into
the quarry.

Wow, it's very hard to just tell
the size of it.

[ ♪♪♪ ]

You walk out of those tunnels,
and then you're in this

unbelievable, massive space.

And how much water
can this thing hold?

7.9 billion gallons' worth
of water when it's done.

In a big storm, how high
would the water eventually get?

The water will get 300 feet
above our heads in a storm.

It'll go all the way up
to the top of this thing?

Almost all the way up
to ground level.

This is like the world's
largest bathtub here.

It is the world's
largest bathtub.

So it's basically just this
kind of giant buffer.

You've got a storm, you can't
deal with all that water,

you've got to put it somewhere.

We need somewhere to put it

that's not polluting
the waterways

and that's not backing up
in people's basements.

This is the location.

It's an amazing solution.

Ellis Chesbrough would've
loved this, right?

He was all about
big projects like this,

and he would've loved
a project like this, I'm sure.

[ ♪♪♪ ]

[ exploding boom ]

Looking at the scale
and expense of this project,

you can understand
just how hard it is

to get clean water
in fast-growing cities.

But today's planners have

a simple but crucial piece
of information

that Chesbrough didn't.

Human waste in drinking water
spreads disease.

To keep people safe, you need
to do everything possible

to stop the two from mixing.

Discovering this one fact

was the single most important
breakthrough

in our understanding of clean.

[ toilet flushes ]

The story of how we made
that breakthrough,

well, it begins with
a mewhat rock 'n' roll

choice of breakfast.

To tell you the truth,

I don't normally have beer
for breakfast,

but actually, for thousands
of years,

this was the healthiest way
to start the day.

Our ancestors liked to have
a drink or two.

Benjamin Franklin in his diaries
recalled how his colleagues

would have a pint of beer
before breakfast,

and then they'd have a pint
with breakfast

and a pint between breakfast
and lunch.

And of course you have to have
some beer with lunch.

By the way, this is the point
at which I need a nap,

but they would charge on
and have a pint

around 6:00 p.m. and then
of course a pint

to celebrate the end
of a hard day's work.

Now, this may seem a little
excessive,

but it's not quite as crazy
as you might think.

[ ♪♪♪ ]

The beer-brewing process
kills disease.

Although no one realizes this

in the middle
of the 19th century,

it means if you live
in an unclean environment,

beer is a very sensible drink.

This quirky fact, that drinking
beer can be safer than water,

will help transform
our understanding of clean.

Ahh!

Beer will prove vital
in solving the mystery

of one of the deadliest killers
in Victorian London.

When we think about killers

in the dark corridors
of 19th-century London,

we might think of
Jack the Ripper.

But the real killer that haunted
the streets was cholera.

Between 1831 and 1860,

cholera killed more than
140,000 people in Britain,

and it did so
in a truly horrific way.

There's a particularly
harrowing account from the time

of a cholera victim
near to death.

It reads, "The mind within
remains untouched and clear,

shining strangely through
the glazed eyes,

a spirit looking out in terror
from a corpse."

Cholera is a horrific disease
that still kills

almost 100,000 people worldwide
every year.

But in the 19th century,

doctors profoundly
misunderstand its cause.

The medical leaders of the time
are convinced

cholera is spread through
the stink in the air.

Proving them wrong
will be a lifelong battle

for this man, John Snow,

a medic from the north
of England

whose experiences as
a young man will lead

to a radical new theory
about the spread of disease.

As an 18-year-old trainee
doctor,

Snow spends nearly a year
in the mines of Killingworth

in the northeast of England,
treating miners

who have been stricken
with cholera.

It's not the most pleasant way
to start a medical practice,

but what he experiences in
the mine will spark an idea

that will follow him
for the rest of his career.

Snow is breathing in
the same putrid air

as the infected miners,

and yet, despite the time
he spends with them,

he doesn't seem to get ill.

Looking around at the appalling
sanitary conditions

that the miners worked in,

with the filth and
the dirty water,

something clicks in Snow's mind.

It's just the glimmer of
an idea, really,

and it might've stayed that way

had he spent the rest of his
life in a small town.

But Snow's idea is going
to blossom

into something truly powerful
when he moves to the city.

[ ♪♪♪ ]

In 1836, John Snow arrives
in Soho in the heart of London.

It's a place where beer
is produced and consumed

on a very large scale.

It's also a place that is ripe
for big ideas,

a place that will help Snow
make his breakthrough.

In the mines of Killingworth,
Snow had noticed

that not everyone
who breathed the air

had come down with cholera.

Now, in London, he attends
public lectures

and learns more about the way
that gases are distributed

in the atmosphere,
and he starts working

on a radical new theory:

cholera is not in the air,
it's in the water.

Snow's radical idea
flies in the face

of the medical establishment's
view

that cholera spreads
through the air.

But to convince them
he's right,

Snow needs irrefutable
evidence.

In 1854, when a deadly cholera
outbreak begins

in the heart of Soho,

Snow realizes it's an
opportunity

to gain the evidence
that he needs.

But to prove his theory,
he's going to have to take

a truly monumental gamble
with his own life.

While the rest of
the neighborhood

is fleeing in terror,

Snow bravely goes from door
to door in Soho,

recording the deaths
at each address.

And with this detective work,
he assembles all the data

and he makes a map.

Now, it may not look like much,
but this is actually

one of the most influential
maps ever produced.

[ ♪♪♪ ]

Overlaid on the map
is the data

John Snow has collected
in Soho.

Each of the black marks

represents a death
from cholera.

As Snow builds up a picture
of what's going on,

the map reveals that the deaths
are concentrated

around a water pump
on Broad Street.

But there's one group of locals
who escape the outbreak:

the beer-drinking workers
at the local brewery.

Unbeknownst to them,
their favorite beverage

has kept them safe from
the dirty water of Soho.

It's all the evidence
John Snow needs.

By risking his life,
Snow has proved

that cholera is spreading
through the water.

It's an insight that will begin
a new chapter

in our understanding
of clean.

Thanks to Snow and his map,

the authorities
finally come around

to one of the most important
principles of public health:

access to clean drinking water
is crucial

for preventing disease.

It's the principle that every
relief worker in the world

now follows after
a major disaster.

But Snow's map will have
consequences

that extend far beyond
just public health.

[ ♪♪♪ ]

Snow's work helps inaugurate

the new science of
epidemiology,

using maps and surveys instead
of lab-based experiments

to uncover the patterns
and causes of disease.

In the 1950s, these techniques
will be used

by British doctor Richard Doll
to reveal that lung cancer

is linked to cigarette smoking
rather than car fumes.

In the 1980s, police forces

will combine data and maps
together

to reveal the previously hidden
patterns and causes

of crime in cities.

It's a technique that will
revolutionize law and order.

Today, the combination
of local data and maps

has become a vital tool
for city dwellers

all over the world.

And all these developments
have their roots

in a map made by John Snow
more than 150 years ago.

[ ♪♪♪ ]

John Snow makes clean water
the goal for civil engineers

in the rest of the century.

The irony is Snow made
his breakthrough

without actually knowing
what it is in dirty water

that kills us.

This little creature
is what John Snow

was actually up against.

It's a tiny organism
that spreads through water

and causes cholera.

If you are unlucky enough to
ingest cholera-infected water,

there will soon be upwards of
a trillion of these creatures

living in your gut.

And that spells death.

[ ♪♪♪ ]

Learning how to control
bacteria in water

would be one of our greatest
challenges in the 20th century.

Even today, for almost
1 billion of us,

drinking a glass of water is
like playing Russian roulette.

But one miraculous chemical
would allow us

to kill these deadly creature,

and in doing so, it would make
much of modern life possible.

A hundred and fifty years ago
in Europe and America,

the public water was so dirty
you wouldn't have wanted

to go near it.

Today, the story is
a little different.

Now we actively seek out
public water,

sharing it with over 80 million
other Americans each year

and their trillions upon
trillions of bacteria.

Whoa!

All these people
are jostling around

in a wonderful bacterial
breeding ground

of 72-degree water,

a temperature that's ripe
for superfast multiplication.

There's a reason why we didn't
have waterparks like this

in the middle of the 19th
century.

There was no way to keep
the water clean.

I mean, imagine what John Snow
would've said about this place.

He would've been baffled by it.

Then again, I don't think he was
much of a waterpark person.

But perhaps what would've
shocked John Snow the most

is that this park operates
a recycle system.

Over 2.5 million gallons
of water

are used over and over
in the rides.

It means keeping it clean
is vitally important.

So now we're behind the scenes.

We've got this water
playland up there.

This is what we need to do
to keep that safe and clean.

We have to filter it
and disinfect it

and do all the good things
that these little magic guys do

to clean 2.5 million gallons
of water at Blastenhoff.

That's a lot of water.

And what happens at
the first stage of filtering?

We have some pre-filters
before things go public.

This is what gets trapped
in the filter...

- In the pre-filter.
- on an average day.

So this is just a small -- oh,
a yummy example just for you.

That is like the world's
largest hairball.

It is like the world's
largest hairball.

You know, we are mammals.

Oh, that's what we just
kind of naturally shed?

- Do you want to touch it?
- No, I really don't.

Are you sure?
It's just a hairball.

Oh -- oh, God!
No, it's in my contract.

I'm not allowed to interact
with hairballs.

It's not that scary.
Some leaves, a little bracelet.

Oh, look, out of someone's shoe.

Can I ask, like, what is
the weirdest thing

you've ever found
in the filters?

Oh, I think one of the weirdest
things is a toupee.

- Really?
- Yeah.

So what happened
to the poor guy?

I assume it was a guy.

He goes onto the ride,
and he's like all Burt Reynolds,

and he shows down at the end,
he's like, "Oop, wait,

I have a slightly different
look, sorry!"

But the objects we can see
make up just a tiny fraction

of what has to be cleaned
out of the water.

What really keeps this place
clean is chlorine,

a chemical that is lethal
to microscopic bacteria.

So what is this giant vat?

Well, this is liquid chlorine
that we inject into the water,

which is our disinfection.

So this is basically what keeps
the whole park safe.

This is the -- you can't have
the magic up there

without this giant vat
of chlorine.

That is the secret and
the magic to water.

Clean water is paramount
to what we do,

and we've got this amazing
team of men and women

that take care of our water.

They're invisible and probably
not as loved and noticed

as they should be,
but all day long,

they make sure that our water
and the magic of the waterpark

starts with good, disinfected,
filtered, clean water.

[ ♪♪♪ ]

We all know chlorine is vital
in waterparks,

but there's a problem.

Use too much chlorine,
and it can be lethal to humans.

It means it was one of those
innovations

that was very hard to sell.

And back when chlorine was
first used to treat water,

itasn't just for
entertainment,

it was a matter of life
and death.

Across America and Europe

at the beginning of
the 20th century,

dirty water was everywhere.

And one technology
in particular

was causing the problem...

the humble flushing toilet.

[ ♪♪♪ ]

The toilet was adopted
by a lot of people

in a very short space
of time.

When this happens, problems
are never very far away.

Just look at the modern world
of high technology.

Think of the iPhone.

This was a huge hit product,
but right after its launch,

it overloaded the wireless
network.

People just had no idea
how much iPhone users

were going to try and get
online.

People even had a hard time
just making telephone calls.

New technologies can often
overwhelm old infrastructure

in really surprising ways.

Please, I just -- I don't know
how I got into this thing,

but I feel a little bit
uncomfortable.

Guys, can you -- can you guys
get me out of here?

[ ♪♪♪ ]

In the 19th century, toilets,
like iPhones,

were a catastrophic success.

People bought and used them
so much

that they overwhelmed
the system.

As many thousands of toilets
were installed

in cities around the world,

there was a huge influx
of dirty water.

As a result, drinking water
became even more lethal.

Finding a solution to this
problem would begin

a new phase in the story
of clean.

What we needed was a way
to kill bacteria

on a truly vast scale.

And the solution wouldn't come
from some genius scientist

but instead from a seemingly
unremarkable guy,

a passionate amateur
who happened to be

in the right place
at the right time.

This guy, John Leal.

He never became rich or famous,

but his work would transform
America.

[ ♪♪♪ ]

John Leal is a doctor at the
beginning of the 20th century,

but it's his special interests
that mark him out

as a bit different.

Leal is obsessed with bacteria
in water.

It's an obsession that had come
from personal tragedy.

His father had died
a slow and painful death

from drinking bad water
during the Civil War.

All of which means that
when he's not spending time

helping his patients,
he's trying to figure out

new ways to kill bacteria.

Leal experiments with
many ways to kill bacteria,

but one poison in particular
excites him:

calcium hypochlorite,
a potentially lethal chemical

that is better known
as chlorine.

Leal's passion for public health
ultimately lands him a job

at a big water company.

It means he's responsible

for 7 billion gallons
of drinking water,

and it's going to enable him
to put chlorine to the test

in the most dramatic way
possible.

[ ♪♪♪ ]

In 1908, the New Jersey water
company he works for

is suffering from an unusually
high bacterial content

in its water.

It's the opportunity Leal
has been waiting for.

So here's where it gets
really insane.

In total secrecy, without any
approval from the authorities,

Leal doses the drinking water
supply

for a city of 200,000 people

with potentially lethal
chlorine.

To the wider world, it appears
as if John Leal is a madman,

poisoning the unsuspecting
citizens of Jersey City.

The public and even many
scientists

are intensely hostile
to the idea of drinking water

being tampered with.

One notable chemist
of the time comments,

"The idea itself of chemical
disinfectant is repellant."

With public opinion
against him,

it's a truly unbelievable risk,
but Leal sticks with his plan.

[ geese calling ]

Three months after
his experiment,

Leal gets called into court
and reveals what he's done.

And the judge is shocked.

Here, I've got the transcript
here.

The judge says,
"Do you drink this water?"

"Yes, sir."

"Habitually?"
"Yes, sir."

"Would you have any hesitation
about giving it

to your wife and family?"

"I believe it is the safest
water in the world."

It's a bold move,
but luckily for Leal,

his gamble is going to pay off
in a major way.

[ ♪♪♪ ]

The project is such a success
that within a few years

the chlorination of drinking
water is rolled out

throughout the U.S.

This is the graph of typhoid
deaths in the U.S.

Look at the point where
chlorination begins.

But it's not just typhoid.

In just a few years,
infant mortality in America

is almost halved.

But Leal's chlorination project
wasn't just saving lives.

It was also transforming
how we have fun.

Post-World War I,
nearly 2,000 public baths

open in America,

and a whole generation
of humans learns how to swim.

Chlorinated pools become spaces
where the old rules

of public decency fade.

As costumes become smaller
and more revealing,

the two-piece suit is born,

and women's fashion
is revolutionized.

The swimming craze will go on
to inspire

over a million American homes
to install private pools

in the 1960s.

After droughts in southern
California in the '70s

leave pools empty...

kids soon discover they're
perfect environments

for their skateboards,

helping them develop a new
range of airborne tricks.

All these developments
have roots

in that huge risk taken
by John Leal,

one of the 20th century's
most unlikely heroes.

But the story of chlorine
isn't just a matter

of giant public health
projects.

It will also bring the clean

revolution into the home

and turn it into big business.

Just a few years after

Leal's breakthrough,

five San Francisco entrepreneurs
invest $100 each

to launch a chlorine-based
bleach.

And it sounds like a great idea,

but things don't turn out
so well.

[ ♪♪♪ ]

The bleach is aimed
at big industry,

but the sales are very poor,

and the business appears
doomed.

But the Clorox Chemical
Corporation,

as they will call themselves,
are destined for success

thanks to a bright idea
from the wife

of one of the investors,
Annie Murray,

and the shop she runs
in Oakland, California.

People, this is --
your kitchens are disgusting.

You need this product.
Kills bugs dead.

Annie Murray is not
one of the boys,

and that means she recognizes
something

that no one else
has considered:

chlorine bleach can become
a revolutionary product

for people's homes.

Acting on her insight,

Murray creates a weaker version
of the chemical

and puts it in smaller bottle.

The store is mostly empty now,
but you could imagine

in 1916, this is a bustling
grocery store.

And Murray is so convinced
of the demand for this product

that she starts giving away
free samples to her customers.

Please try this.
It's very, very dangerous.

I think this is something that
you seem like you could use.

Ah, business is booming!
This is fantastic.

And within months, bottles
are flying off the shelves.

Murray might not have realized
it, but she has invented

an entirely new industry.

[ ♪♪♪ ]

Annie Murray has created

America's first commercial
bleach for the home.

And soon, many other similar
products will be launched.

On hard-to-get-at places
like this,

spray your cloth first,
then dust.

MAN: The motor is started,
and now watch

how each soap performs.

In the 20th century,
Murray and other entrepreneurs

transform ideas about
cleanliness.

Now it's not just about huge
public health projects.

Clean becomes truly
big business.

And nowhere did the clean
business take off

like it did in America.

[ beeps ]

I would say that the big years
for convincing Americans

that they needed to be
really, really, really clean

was the 1920s, because people
were flooding into cities,

men and women
were working together,

very close together,
in offices and in factories,

and they were also
the ambitious ones.

They were the ones
who'd left the farm.

In this new environment,
radio and television

rapidly become popular pastims

for city dwellers
with disposable incomes.

Hey, get back here!

Get back here!

As advertising becomes
increasingly sophisticated,

a new form of drama
will be produced

to help sell cleaning product,

something that has dominated
popular culture

for almost 70 years...

I don't want a baby
from an adoption bureau!

I want it from here!

the soap opera.

The soaps began to sponsor
little daily serials

that were, you know,
hugely dramatic.

Hence the term "soap operas,"

because they were
unsung operas

and always advertised
by soap.

I love the idea that we're
still using that phrase,

- soap opera.
- Yeah.

I mean, it was like
the soap industry

did such a brilliant job
sponsoring shows

60, 70 years ago that we're
still using the term

and promoting the word "soap"
in general.

Thanks to the early pioneers

and some pretty ingenious
marketing,

today the household cleaning
product industry

is worthn estimated
$80 billion.

But there are some who feel
our obsession with cleanliness

may now have gone too far.

[ ♪♪♪ ]

Some research suggests
that our ever-cleaner world

may actually be linked
to increasing rates

of asthma and allergies.

The explosion of cleaning
products

during the 20th century,
for good and for bad,

has led to domestic
environments becoming cleaner

than they've ever been before.

But the ultraclean revolution
didn't just help us

keep our homes germ-free.

It also helped invent
something new,

something we rely on
every second of our lives.

And it's manufactured
in a room behind this door.

It also happens to be
one of the cleanest places

on the planet.

[ ripping sound ]

This is a Texas Instruments
microchip fabrication plant.

The chips made here
power everything

from cars to planes
to microwaves.

This place is a true wonder
of the modern world.

Ooh, nice.

To see inside this unique
environment,

I have to take some extreme
precautions

to make sure I don't
contaminate it in any way.

If you're a visitor
to the building,

then you put shoe covers on.

Okay, great.

Thankfully, clean guru
Sharon Hudgens

is leading me through
the process.

So you're going to rinse
your hands under the water

for a few seconds, and then
completely blow them dry.

Okay.

So I notice we didn't use
any soap.

Actually, a lot of soaps
have fragrances in them,

which is a contaminant.

It would give off particles.

So we're trying to eliminate
particles

going into the clean room.

This is our first step
in eliminating particles.

I like that. So soap is too
dirty for the clean room.

- Soap is too dirty.
- That's nice.

So this is the hood.

Right, I reverse it...

That's not right.
There we go.

[ ♪♪♪ ]

To understand why dust
can be so damaging,

you need to get a sense

of the scale of the chips
produced here.

A human hair measures
about 100 microns across.

A single cell of skin
is about 30 microns.

A cholera bacterium
is 3 microns.

The intricate pathways and
transistors on a microchip

can measure less than a tenth
of a single micron.

A speck of household dust

landing on one of these
delicate silicon wafers

would be comparable
to Mt. Everest

landing in the streets
of Manhattan.

And that is why clean
is so vitally important here.

So this is really
what this is all about, right?

This is a wafer.

It's in an even cleaner
space here, right?

That is correct.

And this is what we're
trying to achieve.

This is a wafer, and there are

thousands of individual
microchips on that wafer.

You can sort of see them
individually,

but it's difficult.

So in a way, the whole
digital revolution

that we celebrate that's
bringing the world together

can only happen because we're
able to think about cleanliness

on the level of microns,
not on the level of the planet.

That's correct.

And it's taken us a long time
to figure out

everything we need to do

to make sure we're
as clean as we can be.

[ ♪♪♪ ]

Being able to master clean
at the smallest scale

has transformed our world.

But the roots of all this
stem from a simple desire

almost 200 years ago

to keep our city streets
free of dirt.

Standing here in the clean room,

I can't help but think
of the sewers.

In a way, it's really
the two poles

of human inventiveness, right?

To be able to build
the modern world,

we had to create this incredibly
disgusting space

that we isolated from
everyday life.

And at the same time, to make
the digital revolution,

we had to create this
hyperclean place

and also isolate everyone
from it.

And we never get to visit
these environments.

We never really see them.
We don't even think about them.

But without this kind
of environment

and without the incredible dirt
and disgust of the sewer,

modern life wouldn't be
possible.

[ ♪♪♪ ]

Bit by bit, clean technologies
have transformed our world.

But the story of clean
has really only just begun.

Every year, millions of people
die needlessly as a result

of not having access to clean,
safe drinking water.

It's one of the great tragedies
of the modern world.

Bringing the benefits of clean
water to every human on Earth

is one of the great challenges
of the 21st century.

Developing ways
to keep things clean

has allowed cities to flouris.

And that's important,
because these places

are some of our most creative
spaces,

environments that drive
new innovation

as ideas and cultures collide.

When clean pioneer John Snow
was born,

little more than 2% of humans
lived in cities.

Today more than half of us do.

We have become a species
of city dwellers.

The urbanization of the planet
would've never happened

without the ideas
and technologies

that made our cities clean.

The people behind that
revolution

didn't become rich or famous,

but look around at a modern,
thriving, dynamic city today,

and it's clear that they,
as much as anyone,

invented the modern world.

[ horn blows ]

In the next episode,

I'm looking at the strange
and surprising story of time.

From mavericks to madmen...

One magazine goes so far
as to call him

"the lunatic of Boston."

these are the men and women
who transformed time

and changed the world
in ways you'd never imagine.

Every second counts
as a departure controller.

So I probably shouldn't
check Facebook

while I'm in the middle
of this?