How to transform sinking cities into landscapes that fight floods

From London to Tokyo, climate change is causing cities to sink -- and our modern concrete infrastructure is making us even more vulnerable to severe flooding, says landscape architect and TED Fellow Kotchakorn Voraakhom. But what if we could design cities to help fight floods? In this inspiring talk, Voraakhom shows how she developed a massive park in Bangkok that can hold a million gallons of rainwater, calling for more climate change solutions that connect cities back to nature.

At this very moment,

with every breath we take,

major delta cities
across the globe are sinking,

including New York, London,

Tokyo, Shanghai, New Orleans,

and as well as my city, Bangkok.

Here is the usual version
of climate change.

This is mine.

Nothing much,

just a crocodile on the street.

(Laughter)

This is an urgent impact
of climate change:

over sinking cities.

Here, you can see
the urbanization of Bangkok,

growing in every direction,

shifting from porous, agricultural land --

the land that can breathe
and absorb water --

to a concrete jungle.

This is what parts of it look like
after 30 minutes of rainfall.

And every time it rains,

I wish my car could turn into a boat.

This land has no room for water.

It has lost its absorbent capacity.

The reality of Bangkok's
metropolitan region

is a city of 15 million people

living, working and commuting
on top of a shifting, muddy river delta.

Bangkok is sinking
more than one centimeter per year,

which is four times faster
than the rate of predicted sea level rise.

And we could be below sea level by 2030,

which will be here too soon.

There is no coincidence that I am here
as a landscape architect.

As a child, I grew up in a row house

next to the busy road
always filled with traffic.

In front of my house,
there was a concrete parking lot,

and that was my playground.

The only living creature I would find,

and had fun with,

were these sneaky little plants
trying to grow through the crack

of the concrete pavement.

My favorite game with friends

was to dig a bigger
and bigger hole through this crack

to let this little plant creep out --

sneak out more and more.

And yes, landscape architecture

gives me the opportunity
to continue my cracking ambition --

(Laughter)

to connect this concrete land
back to nature.

Before, Thais -- my people --

we were adapted to the cycle
of the wet and dry season,

and you could call us amphibious.

(Laughter)

We lived both on land and on water.

We were adapted to both.

And flooding was a happy event,
when the water fertilized our land.

But now, flooding means ...

disaster.

In 2011,

Thailand was hit by the most damaging
and the most expensive flood disaster

in our history.

Flooding has turned central Thailand
into an enormous lake.

Here, you can see the scale of the flood
in the center of the image,

to the scale of Bangkok,
outlined in yellow.

The water was overflowing from the north,

making its way across several provinces.

Millions of my people,

including me and my family,

were displaced and homeless.

Some had to escape the city.

Many were terrified of losing
their home and their belongings,

so they stayed back in the flood
with no electricity and clean water.

For me, this flood reflects clearly

that our modern infrastructure,

and especially our notion
of fighting flood with concrete,

had made us so extremely vulnerable
to the climate uncertainty.

But in the heart of this disaster,

I found my calling.

I cannot just sit and wait
as my city continues to sink.

The city needed me,

and I had the ability to fix this problem.

Six years ago,

I started my project.

My teams and I won the design competition
for Chulalongkorn Centenary Park.

This was the big, bold mission
of the first university in Thailand

for celebrating its hundredth anniversary

by giving this piece of land
as a public park to our city.

Having a park sounds very normal
to many other cities,

but not in Bangkok,

which has one of the lowest
public green space per capita

among megacities in Asia.

Our project's become
the first new public park

in almost 30 years.

The 11-acre park --

a big green crack
at the heart of Bangkok --

opened just last year.

(Applause and cheers)

Thank you.

(Applause)

For four years, we have pushed
through countless meetings

to convince and never
give up to convincing

that this park isn't just
for beautification or recreation:

it must help the city deal with water,

it must help the city
confront climate change.

And here is how it works.

Bangkok is a flat city,

so we harnessed the power of gravity
by inclining the whole park

to collect every drop of rain.

The gravity force pulls down
the runoff from the highest point

to the lowest point.

This park has three main elements
that work as one system.

The first -- the green roof.

This is the biggest
green roof in Thailand,

with the rainwater tanks
and museum underneath.

In the dry season,

the collected rain can be used
to water the park for up to a month.

The runoff on the green roof
then falls through wetlands

with the native water plants
that can help filter

and help clean water.

And at the lower end,

the retention pond
collects all of the water.

At this pond, there are water bikes.

People can pedal and help clean water.

Their exercise becomes an active part
of the park water system.

When life gives you a flood,

you have fun with the water.

(Laughter)

Centenary Park gives room for people
and room for water,

which is exactly
what we and our cities need.

This is an amphibious design.

This park is not
about getting rid of flood.

It's about creating a way to live with it.

And not a single drop of rain
is wasted in this park.

This park can hold and collect
a million gallons of water.

(Applause)

Thank you.

(Applause)

Every given project, for me,
is an opportunity

to create more green cracks
through this concrete jungle

by using landscape architecture
as a solution,

like turning this concrete roof
into an urban farm,

which can help absorb rain;

reduce urban heat island

and grow food in the middle of the city;

reuse the abandoned concrete structure

to become a green pedestrian bridge;

and another flood-proof park
at Thammasat University,

which nearly completes the biggest
green roof on an academic campus yet

in Southeast Asia.

Severe flooding is our new normal,

putting the southeast Asian region --

the region with the most coastline --

at extreme risk.

Creating a park is just one solution.

The awareness of climate change

means we, in every profession
we are involved,

are increasingly obligated
to understand the climate risk

and put whatever we are working on
as part of the solution.

Because if our cities continue

the way they are now,

a similar catastrophe
will happen again ...

and again.

Creating a solution
in these sinking cities

is like making the impossible possible.

And for that,

I would like to share one word
that I always keep in mind,

that is, "tangjai."

The literal translation
for "tang" is "to firmly stand,"

and "jai" means "heart."

Firmly stand your heart at your goal.

In Thai language,
when you commit to do something,

you put tangjai in front of your word,

so your heart will be in your action.

No matter how rough the path,

how big the crack,

you push through to your goal,

because that's where your heart is.

And yes, Thailand is home.

This land is my only home,

and that's where I firmly stand my heart.

Where do you stand yours?

Thank you.

(Applause)

Thank you.

Kòp kun ka.

(Applause and cheers)