NARRATOR: It's a city's worst nightmare.
Megastorm Sandy delivers a wall of water 14 feet high...
MARC MENDE: There was no way to stop it.
NARRATOR: ...plowing into New York.
MENDE: You needed Superman, I guess.
NARRATOR: And across the region, crucial services collapse.
DAVID HOLLAND: This is Manhattan, and it was just chaos.
NARRATOR: Miles of coastline are devastated.
DAN MUNDY, SR: Whatever anybody could do,
it was not enough.
And who's to say it ain't going to happen again?
NARRATOR: But there is little doubt it will.
The planet is heating up.
Glaciers are melting.
Sea level is rising.
HOLLAND: Should warm ocean currents reach these glaciers,
all hell could break loose.
NARRATOR: How do we protect ourselves?
Can we wall off our cities from the sea?
Are some places destined to disappear?
Florida is doomed.
NARRATOR: In the wake of Sandy,
how will we respond?
STEVEN FLYNN: This is screaming at us that we need to be better prepared.
NARRATOR: "Megastorm Aftermath," right now on NOVA.
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NARRATOR: New Yorkers pride themselves on being tough...
We'll ride it out like we ride all of them out, you know?
NARRATOR: ...resilient, nonplussed,
and maybe a little cocky in the face of adversity.
MAN: It's raining here,
but, um, you know, whatever, it's a little rain.
What are you going to do?
NARRATOR: But on October 29, 2012...
This is a record surge of water rushing over the edge
of Lower Manhattan.
NARRATOR: ...they, and their city, met their match.
MIKE HERZOG: My God, it's washing everything away!
NARRATOR: That was the day megastorm Sandy came rolling into town.
The storm is on top of us right now.
NARRATOR: It was the biggest, most devastating storm
to hit the city in recorded history.
Strong winds pushed a huge wall of ocean water
14 feet higher than sea level, onto the coast,
covering 51 square miles of the city.
70,000 homes and apartments were damaged.
An entire neighborhood burned to the ground.
Utilities failed in spectacular, massive fashion.
And 43 people died here, most of them drowned.
Sandy brought mighty Gotham and much of New Jersey
to their knees.
As soon as the waters recede, unsettling questions
begin to roll in.
Was Sandy a freak event, or a window into our future?
We live in a new era.
Greenhouse gases like carbon dioxide
generated by burning fossil fuels are building up
in our atmosphere, insulating our planet,
holding in more of the sun's heat
and driving the temperature up.
The Earth's climate is changing.
No one knows exactly how that will affect our weather
day to day.
But there's one thing scientists agree on:
as the Earth and its oceans heat up,
warm water takes up more volume than cold.
At the same time, glaciers are melting.
The result-- sea level around the world is rising.
And that means as the storms come...
coastal cities are more and more at risk.
Climate change will raise the sea level,
and sea level will contribute to the power of flooding.
NARRATOR: It's not only New York and New Jersey
that are in the crosshairs, but Miami, New Orleans, Charleston.
As our sea level continues to rise,
it won't take a Hurricane Andrew or Katrina-size storm
to create flooding hazards along our coastline.
NARRATOR: Thousands of miles of coastline all around the world--
China, India, Japan.
FLYNN: We live increasingly in coastal areas.
This is screaming at us
that we need to be better prepared.
NARRATOR: But what can coastal cities do
to prepare and protect themselves?
Can we engineer a solution
and wall off our cities from the sea?
Or are some areas just too hard to protect,
and, eventually, should they be abandoned?
JACOB: We have to start to retreat
from the most exposed waterfront.
MICHAEL BLOOMBERG: As New Yorkers, we cannot
and we will not abandon our waterfront.
It is one of our greatest assets.
NARRATOR: Or is there another way?
A way to embrace nature's defenses and the water,
even as we try to keep it at bay?
FLYNN: Sandy should demand a national response.
There but for the grace of God, it could have been Boston,
it could have been Seattle.
It could happen to Houston.
How are we as a nation prepared for dealing
with these kinds of risks?
And reality is we're not near as prepared as we need to be.
NARRATOR: As Sandy approached, Dan Mundy knew his home was at risk.
The retired firefighter lives in one
of the most flood-prone neighborhoods of New York City--
Broad Channel.
It's a sliver of an island in the middle of Jamaica Bay,
on the southern end of Queens.
Elevation above sea level: about four feet.
MUNDY: It's very unique what we have here.
It's very different.
People that don't know and come and visit and see it,
they say, "Wow! This is beautiful.
Look at your views."
NARRATOR: Well aware that his home was in harm's way,
Dan Mundy built his own private seawall around it.
MUNDY: You can see my bulkhead out there.
There's 250 tons of stone.
NARRATOR: But the fortress couldn't hold back Sandy's storm surge.
MUNDY: You see how high it is and how big it is.
Well, Sandy come over the top of it.
It was just unreal.
This storm, it just went beyond.
Whatever anybody could do, it was not enough.
And, you know, who's to say it ain't going to happen again?
NARRATOR: That's the question haunting thousands
whose homes were damaged or destroyed by the sea.
Sandy's waves tore through the Rockaways,
about five feet above sea level.
The Red Hook section of Brooklyn: eight feet.
Staten Island: four feet above sea level.
Lower Manhattan: about eight feet at the Battery.
In New Jersey, Sandy caused flooding
from Hoboken to Atlantic City.
Around the region and around the world,
the question is not if it will happen again,
but when, and how often?
JACOB: We know very well a mean trend where things go.
The sea level rise will not go down.
We know that for sure.
NARRATOR: What scientists don't know for sure
is how fast it will rise.
Over the past century, sea level around New York
is up about a foot, partly because of subsiding land.
But how much will it rise in the next hundred years?
That may depend on what happens here...
in Greenland...
where vast masses of ice are flowing from land to ocean,
raising the sea level.
David Holland is trying to crack the sea level mystery.
That's what's brought him here on a hazardous voyage
though the iceberg-cluttered waters of Jakobshavn Fjord
in Greenland.
They say the iceberg that sank the Titanic
came from this breathtaking and extremely dangerous place.
HOLLAND: These things roll.
And if it rolls, it will take the ship with it.
NARRATOR: Holland is a mathematician,
and he's here because he doesn't have much faith in the numbers.
I would state that at this moment
we cannot project future sea level mathematically.
We have to be honest with ourselves.
We have incomplete knowledge at the moment and incomplete data.
NARRATOR: Some of the data we do have is disturbing.
An enormous reservoir of fresh water is locked up
in the glaciers here, at least for now.
HOLLAND: If you melted all of Greenland, then local sea level
around the planet would rise just over 20 feet.
NARRATOR: 20 feet would submerge more than a third of the city of New York.
But no one is predicting that this will happen anytime soon.
NARRATOR: The Greenland glaciers have been slowly melting
for thousands of years, since the end of the last Ice Age.
But today, with the planet heating up faster,
there are ominous signs that the movement of ice
from land to sea might be speeding up.
David Holland believes
the reason lies not in the warming air,
but in the water.
As a glacier slides off the land,
its underside comes into contact with the seawater.
In 1997, the ocean currents changed abruptly,
and the water here got warmer by nearly three degrees Fahrenheit.
Soon the glacier started melting much faster.
During the 20th century, it retreated eight miles.
But in just the first decade of the 21st century,
it receded another nine miles.
David Holland is trying to solve the mystery
of why this happened, and if it could happen again.
HOLLAND: The main thing we're trying to study is
how do warm currents approach ice sheets?
Why is it that sometimes we see warm water
near ice sheets, and sometimes not?
The answer to that question is ultimately the answer
to the future of the sea level.
I'm going to start the next cast.
NARRATOR: To try to find that answer,
he repeatedly sends a probe brimming with instruments
below the surface to depths of 300 feet and more,
testing the water's temperature, oxygen content and salinity.
Because all this water is not created equal.
The water near the surface is less salty,
diluted by the fresh water from the recent glacier melt.
Usually cold water sinks.
But not in this case.
HOLLAND: Fresh water is light, and it floats on top of the ocean.
NARRATOR: Below it is the saltier ocean water
that is warmer than the water above it.
Holland has found much of it comes from the tropics,
carried to Greenland by the Gulf Stream.
It eats away at the glacier's underbelly,
eventually causing big pieces to break off,
making more icebergs, putting more water in the sea.
Holland is determined to discover more
about the dynamic between ice and ocean.
So he also submerges probes for a year...
drops some from helicopters...
and even attaches sensors to deep diving seals.
Still, they're just pinpricks of light in a dark void.
There is little known about how glaciers move and melt--
not just here in Greenland, but in Antarctica, too.
HOLLAND: If you melted Antarctica,
you would raise global sea level, say, 200 feet.
NARRATOR: 200 feet would flood
every city on the Eastern Seaboard
and the Gulf of Mexico.
The Florida peninsula would be long gone.
HOLLAND: That is not going to happen tomorrow morning.
NARRATOR: The vast majority of Antarctic ice is stable.
But a few ice sheets in the west sit on ground below sea level,
making them more vulnerable to melting.
In 2002, the Larsen B ice shelf, a floating piece of ice
the size of Rhode Island, suddenly broke up,
allowing the glacier behind it to flow faster into the ocean.
David Holland worries it could happen again
to other glaciers nearby.
HOLLAND: These areas are enormous, and warm water is near.
So should warm ocean currents in the Southern Hemisphere
reach to these glaciers, all hell could break loose.
NARRATOR: With so many unknowns, the current official estimate
for sea level rise ranges from two to five feet
over the next century.
But David Holland thinks that if we want to protect
coastal cities, we should be prepared for much more.
HOLLAND: If you were to say to me,
"For the next hundred years, I want to be conservative
and protect things,"
I would build walls three meters, ten feet.
NARRATOR: When it comes to flood protection,
Holland knows firsthand some of the dangers of building too low.
HOLLAND: Is it sinking?
NARRATOR: Because when he's not investigating the glaciers
of Greenland, he lives here, in the heart of Manhattan.
When Sandy struck, he and his wife Denise
were high and dry in their apartment.
And then the lights went out... and stayed out for five days.
There was no power, no heat, no water.
HOLLAND: It was surreal,
the concept that this major city, Manhattan,
with this massive infrastructure could be brought to its knees
by a storm.
It was just chaos.
NARRATOR: The Hollands were among the quarter million New Yorkers
who were in the dark because of this spectacular event.
The Consolidated Edison power substation
sits at the end of 14th Street, right next to the East River,
about six feet above sea level.
Water and electricity does not mix, obviously.
NARRATOR: Most of the electricity for Lower Manhattan
flows through these transformers and relays,
as long as they're not under water.
For over 50 years, the 11-foot-high floodwalls
worked just fine, until Sandy's storm surge
pushed 14 feet of water over the banks of the East River.
Our hundred-year flood design was down here.
And the waters were coming over this capstan.
NARRATOR: The flash point was a circuit breaker that shorted out
after the salt water rushed in.
SCHIMMENTI: That breaker was at a lower elevation.
And as the water started to rise,
that breaker flashed over
and then caused a subsequent failure at the transformer.
And so then you saw this big flash of light.
Then there was a cascading failure
because of the other relays.
And then the station ended up being shut down.
NARRATOR: ConEd is determined to keep this station dry
whenever the next megastorm hits.
They're building about 180 aluminum doors
to plug any holes in the substation's protective ring.
SCHIMMENTI: So if the same event occurred
and the same storm surge occurred,
there'd be no customers out in Manhattan.
NARRATOR: And beneath the sidewalks all across the city,
workers are installing waterproof equipment.
Everything in this hole, even if you submerge it under water,
it is all submergible equipment.
If it's underwater, it will still operate normally.
NARRATOR: And they're deploying more smart grid technology
that can be monitored remotely and reduce power outages.
SCHIMMENTI: What we'll do over the long term
is work with the latest climate science
so that we're further protected in the future.
NARRATOR: The electrical grid is just one piece
of the vast infrastructure clobbered by megastorm Sandy.
On the West Side of Manhattan, the phone company Verizon
also got a climate change wakeup call.
CHRIS LEVENDOS: The impact of Hurricane Sandy
to Verizon was the largest impact
to our wireline infrastructure in our 100-year history.
NARRATOR: Verizon world headquarters sits at 140 West Street,
about 250 yards from the Hudson River,
about five and a half feet above sea level.
The ornate Art Deco lobby is normally gilded and gleaming,
but the night Sandy roared in, it was not
such a pretty picture.
LEVENDOS: We had water come in
through the front and rear doors of the building.
And then water gets into the elevator shafts,
down the stair walls, and begins to fill up
the five sub-basements of this building.
NARRATOR: In the basement is the vault
where Verizon keeps its crown jewels--
telephone cables, most of them copper,
the wires that connect their landline phone customers.
Bad enough, but below the vault is a pump system
that delivers diesel fuel to the emergency generators
on the tenth floor.
But the pump was not waterproof.
When it failed, the dominoes started falling.
No pump, no power.
No power, and these crucial machines stop working--
air compressors.
Verizon pumps air into its copper cables
to keep water from seeping in.
Water, especially seawater, destroys copper.
LEVENDOS: The network was completely destroyed
with one massive storm in one very destructive night.
NARRATOR: The loss of that pump was a crucial failure
in a night filled with catastrophic damage
due to relentless flooding.
By morning, the land-based phone lines in Lower Manhattan
were almost totally wiped out, right in the financial capital
of America.
But there was, literally and figuratively,
one glimmer of light amid the unimaginable mess.
Fiber optic cables, long, thin strands of glass
that transmit voice and data with bursts of light,
are far more efficient than copper wires.
And best of all, they're impervious to water.
After Sandy, the company immediately
started replacing its entire copper wire network
in Lower Manhattan with fiber.
The changeover was supposed to take years.
Verizon did it in six months.
In all, Sandy cost Verizon about $1 billion.
And that crucial fuel pump?
It's now in a watertight room with a submarine door.
Protecting New York's vulnerable and venerable subway system
may be the biggest challenge of all.
Sandy caused about $5 billion worth of harm
to the nation's largest transit system.
Hardest hit, South Ferry Station,
at the southern tip of Manhattan.
The station was only three years old,
built at a cost of $550 million.
The day after Sandy, it lay in ruins.
One of the culprits is believed to be
this bundle of lumber, 2x8s.
After becoming flotsam in the roiling seas,
it tore through the makeshift barrier
workers had erected at the station's entrance
as Sandy approached.
JOE LEADER: It was probably like a battering ram.
When that wave effect came in the surges,
it probably just blew right through,
I mean, and that was it.
Where it came from, nobody knows; I don't want to say.
I don't want to give Jersey a bad name.
But it came from somewhere.
NARRATOR: More than 60 million gallons of seawater
came rushing in, filling the station almost to street level.
LEADER: You try and prevent it, you try and deter it, you know,
and that's the best thing you can do.
But can you really actually stop it?
NARRATOR: It was not for lack of trying.
As Sandy bore down on the city,
transit workers frantically fought to stem the tide
with inflatable dams, sandbags and plywood.
But there was no stopping the water.
Subway stations, railyards and nine tunnels flooded.
Water was coming from everywhere.
There was no way of stopping it.
You needed Superman, I guess.
NARRATOR: At the Hugh Carey Brooklyn-Battery Tunnel,
which normally carries cars and trucks
between Brooklyn and Lower Manhattan,
there was little they could do.
We abandoned the place.
We basically pulled everybody out of here.
Marc, come on, we've got to go!
NARRATOR: 80 million gallons of seawater gushed in.
The tunnel was practically full.
Work crews managed to clean it up.
They removed the ceiling tiles and replaced enough lighting,
cameras and communications gear to reopen the tunnel
just two weeks after the storm.
But there are years of work ahead
to get things back to their pre-Sandy condition.
Ten months after Sandy hit, engineers tested
a water-filled emergency dam that might offer
a layer of defense for the tunnel the next time.
They are also considering this idea
from West Virginia University-- an inflatable plug.
In the meantime, carpenters have erected this plywood wall
at the low point, where the water gushed in.
But in the long run, will plywood and inflatables
and other small-scale changes be enough
to protect this metropolis?
LEADER: If I made this airtight
and we did not allow the 66 million gallons of water
that we pumped out to come into our system,
where would that water be?
It would be in the streets, and would be in the basements,
and on the first floors of all the buildings surrounding.
So it's more than just us preventing the water
to come out.
It's got to be a really regional issue to decide,
how do you deal with something like that?
NARRATOR: In the face of rising sea levels,
how can an entire region be protected?
With the threat growing every day,
experts are looking for answers in a place all too familiar
with the war against water-- the Netherlands.
The name itself says it all, "The Low Lands."
Built on a swampy delta,
much of the country lies below sea level.
You really wonder why people settled here at all.
This must have been such an uninhabitable,
inhospitable place.
It's a very soggy delta.
NARRATOR: That's what these are for.
Windmills are essentially pumps.
PETER PAUL KLAPWYK: If the sails turn,
the wheel will turn.
This will start spinning, and the screw gets turned.
NARRATOR: A giant Archimedean screw lifts the water out of the floodplain.
In 1450, when they were introduced,
this enabled us to live in areas
where before we couldn't live.
NARRATOR: And then, of course, there are the dikes, or levees--
massive walls usually made of earth,
built to hold back flood waters.
So really that's what the Dutch have been doing
for a long time, is defending their country
from the water, and defending also implies
the feeling of the water as an enemy.
NARRATOR: In the winter of 1953, the enemy got the upper hand.
A violent storm blew in from the North Sea.
It was their Sandy and Katrina combined.
METZ: In one night, over 1,800 people lost their lives.
Several hundred thousand lost their houses.
About a million animals drowned.
JOS GELUK: My family knows what it is
when your house is blown away by the water.
And after that flood, we said,
"Well, this may never happen again."
And that was the reason for designing the Delta program.
NARRATOR: Jos Geluk is an engineer for the Delta program,
or Delta Works, the massive flood protection system
launched in the wake of the '53 flood.
In addition to a reinforced system of dams and dikes,
locks and levees, the Dutch added what they hoped
would be the ultimate weapons in water defense--
enormous storm surge barriers
across the mouths of rivers and estuaries.
Protecting Rotterdam Harbor are two giant gates,
together bigger than the Empire State Building,
designed to swing shut if the North Sea threatens.
And bigger still, 50 miles southwest of Rotterdam,
a five-and-a-half-mile long storm surge barrier
with 62 doors, ready to close at the push of a button.
GELUK: We designed on a chance of flooding
of once in 4,000 years.
NARRATOR: If New York City wants to stay dry
in a world with rising seas, should structures like these
be part of the plan?
GELUK: I think more and more
the Americans become aware of the threat of the water,
and they will spend money on protecting against the water.
JEROEN AERTS: As a Dutchman, you are quite surprised to see
a large city like New York, so many people exposed,
and no levees, no protection at all... was astonishing to me.
NARRATOR: Jeroen Aerts is a professor of risk and water management
in Amsterdam.
Like many of his colleagues here, he is a big believer
in big structures to keep the water out.
He thinks New Yorkers should think
about walling themselves off from future megastorms.
Don't rule out yet the barriers,
because if sea level is going to rise very quickly,
then you need a barrier.
NARRATOR: But with so many inlets for the sea to flow through,
one barrier would never be enough to protect New York
and New Jersey.
The region would need to build an elaborate ring
of strategically located barriers to fend off flooding
from rising seas and worsening storms.
One scheme imagines a huge structure
at the Verrazano Narrows, which separates Staten Island
and Brooklyn.
The concept is a hybrid of two Dutch designs--
the giant barrier with the gates,
and the huge swinging doors.
Another idea is even more ambitious--
a five-mile-long storm surge barrier
that would span from Sandy Hook, New Jersey,
to the Rockaway Peninsula in New York.
Engineer Jonathan Goldstick would love to build it,
though he admits Fortress New York would cost
tens of billions of dollars.
GOLDSTICK: The cost benefit analysis is tricky.
But it's a very good return, and it really keeps the water out.
NARRATOR: As sea levels continue rising, at some point in the future,
even barriers like this won't be high enough.
GOLDSTICK: What the barrier should do is provide us
with a relatively short-term option for protection
while we implement a plan that gets the city ready
for future higher sea level rises.
If I were king of New York, I would build it.
NARRATOR: But if billions are spent on colossal barriers,
will New Yorkers be left with a false sense of security?
And might that delay action on the crucial question
of how and where to build?
KLAUS JACOB: It looks like, "Wow, there's this incredible benefit."
But essentially, we have delayed the problem.
NARRATOR: Even in the short term, giant barriers can cause
huge problems.
Just ask the Dutch.
There were a lot of unintended consequences.
It's turned out that a lot of this intervention
to keep the water out has had a detrimental effect
on the country's ecology.
NARRATOR: Behind the permanent sea walls, they created stagnant lakes
that are plagued by noxious algae blooms.
The doors on the giant storm surge barrier
were added to address that problem.
But even with the doors open, the permanent barrier structures
and manmade islands reduce the ebb and flow
of the tides by 30%.
Precious little sediment flows in.
As a result, the estuary's sandbars, wetlands
and oyster beds are disappearing,
taking with them the natural flood protection
they used to provide.
This is really one of the reasons
that the Dutch are moving now towards a new approach
to dealing with water and trying to intervene less.
NARRATOR: The reality is, the quest to control
big bodies of water almost always produces big problems.
And nowhere is that more obvious than in the heart of America,
on the mighty Mississippi.
Since the 19th century, the U.S. Army Corps of Engineers
has been on a mission to prevent flooding
and keep the river in its place with big reinforced levees
and giant articulated concrete mats
laid along the banks to prevent erosion.
DENISE REED: What we did in the 20th century
was we really isolated the river from its delta plain.
Then we decided that we really needed
to essentially eliminate flooding
from the Mississippi River under most circumstances.
NARRATOR: Geomorphologist Denise Reed understands that rivers
are meant to flood.
That's why here in bayou country,
south of New Orleans, she lives in a house on stilts.
One of Reed's biggest worries
is that in our fight to stop flooding, we've essentially
turned the river into a giant concrete pipe.
REED: The sediment that comes out of the end of the Mississippi
comes out of that long pipe that we've made.
That essentially drops down into fairly deep water.
That's not the way it used to work.
NARRATOR: The way it worked for thousands of years
allowed sediment to spread out at the mouth of the river,
creating the vast wetlands and swamps of the Mississippi Delta.
But today, the delta is starved of sediment.
As a result, every 40 minutes or so, an area of marsh
the size of a football field vanishes.
REED: It's almost like a Swiss cheese effect.
We've lost, I guess, since the 1930s,
an area the size of Delaware.
That's a pretty large area.
NARRATOR: Those vanishing wetlands and marshes
are nature's best defense against a storm,
acting like giant speed bumps
for waves surging in from the sea.
In the world of water control, they're known as soft defenses.
REED: So imagine the storm surge coming in.
Instead of moving across a very smooth sandy bottom,
it's moving across a rough surface.
And that really starts to take some of the energy out
and slow down the storm surge.
NARRATOR: But by how much?
To try and find an answer, the Corps of Engineers
is using a complex model that runs on this supercomputer.
Hydraulic engineer Jane McKee Smith has simulated
a typical storm
without the benefit of the wetlands that exist today
near New Orleans.
You get larger storm surge and bigger waves hitting the area.
And certainly if you look back
the way they were hundreds of years ago, you would see
a protective benefit from those wetlands.
So it's a very big issue.
REED: And if they continue to degrade, then clearly
the city of New Orleans is not going to be protected
the way we think it is now.
NARRATOR: New Orleans sits right in the midst of the Mississippi Delta.
Today, the city is regaining its swagger,
in part thanks to this-- 133 miles of new surge barriers,
levees, floodwalls, gated structures
and pumping stations that now ring the city.
The $14.5 billion project, the epitome of hard defenses,
was built by the Corps of Engineers
in the wake of Hurricane Katrina.
We moved the perimeter outward.
And so, in some ways, you know, we took the fight out
to the storm surge
instead of letting the storm surge come into the city.
NARRATOR: In August of 2012,
Hurricane Isaac gave the hard defense system
its first big test.
The storm brought 80-mile-an-hour winds
and a surge that was only two feet lower than Katrina.
This time the city did not flood.
But Denise Reed worries that if things don't change,
this low-lying city will not be safe for long.
REED: If we have a city behind a levee
and just open water on the other side,
I don't think anybody thinks that is as good a condition
as having a city and a levee
and extensive wetlands on the other side.
NARRATOR: To make matters worse,
scientists say the city and the wetlands are sinking,
or subsiding.
The state of Louisiana is fighting back,
pumping millions of tons of sand onto barrier islands
and decimated marshes.
The goal-- engineering a solution that replicates
the way nature disperses that famous Mississippi mud.
So, can New York find a balance
between hard barriers and soft defenses?
We're going to pull up the ropes and check them out.
NARRATOR: Landscape architect Kate Orff prefers the soft approach.
This is a typical blue mussel
that we are looking to recruit on this rope.
NARRATOR: Orff says the blue mussels clinging to these ropes
could be a lifeline for New York Harbor
and help the city survive a wetter future.
The mussels are a keystone species,
the first small step toward Orff's grand vision--
a harbor filled with vibrant shellfish beds
and small islands,
offering a natural defense against high water.
ORFF: You can't just think
about resiliency as closing the gates,
you know, putting up a giant sea wall.
But rather through introducing reefs and offshore islands,
ecological systems and marine life can play a role
in making a more resilient harbor.
I think we've learned over the past 100 years
that you cannot isolate these problems,
that we live in an ecosystem
where everything is interconnected.
Hold it!
NARRATOR: Even though retired fire captain Dan Mundy
spent a lot on hard defenses
at his waterfront home in Broad Channel,
he's an evangelist for the gospel of soft measures,
especially in the marshes of Jamaica Bay.
MUNDY: As children, we used to drive our boats through these,
so we knew these islands, these marsh islands,
like the back of our hand.
We knew how big, how wide the creek was,
we knew where your turns were, and whatnot.
NARRATOR: Then, in the 1990s, he noticed that things were changing.
MUNDY: The creeks got wider, the openings fell apart,
and instead of coming in and making a turn,
it was just a big opening.
NARRATOR: Along with his son, also Dan, Mundy collected
old maps and aerial photos of the marshes
and compared them to new views.
MUNDY: And when we looked at the interior of the marsh,
looking, like, overhead and looking down, we found out
the whole interior was like a cancer.
It was eaten out from the inside out.
NARRATOR: The Mundys helped launch
a scientific investigation.
The findings were chilling.
Jamaica Bay was losing 33 acres of marshland a year.
Eventually, scientists believed they found the culprit.
Polluted water was killing the sea grass.
MUNDY: These plants that we see,
the roots are like arteries-- they go out feet.
NARRATOR: Without the web of sea grass roots knitting them together,
the sandy islands dissolved away.
Since then, the Mundys have spent years
trying to save the marshes, with impressive results.
Today, pollution is down.
The water quality is up.
They've helped raise millions of dollars to rebuild
many of the islands, including this one.
And they organize volunteer groups to plant
new sea grass to hold the sand together.
MUNDY: And look at this.
We have new growth coming up in this area.
That's the most encouraging thing
that I've seen since I started this project,
because this means that they're going to be well established.
We can let this go by itself now.
NARRATOR: The Mundys are stubbornly committed
to this place, even though they live on the front lines
of the battle against sea level rise.
MUNDY: We're not moving.
A little water ain't scaring us away.
Do we retreat from the tornado alleys,
do we retreat from the mudslides,
and do we retreat from the forest fires?
So if we apply that mentality across the board,
there's really not many places we want to live.
NARRATOR: For them, natural defenses are a key weapon in the fight.
MUNDY (father): We're going to get the water quality back
to the way it used to be, going to rebuild these marshes
that have disappeared.
And that all is going to help with resiliency for the future.
It's going to protect the shorelines.
NARRATOR: The Mundys found an unlikely ally in their quest
to rebuild the marshes of Jamaica Bay--
the Army Corps of Engineers, which built the new islands.
The Corps, now aware of the mistakes it made
managing the Mississippi, seems to be going soft.
JOE VIETRI: We have to think about a healthy estuary system
with salt marsh and soft wave-absorbing type features
like islands and things of that sort.
You can use a combination of gray and green infrastructure,
gray being our traditional concrete-type things,
and green being those softer solution sets.
We know a lot about the hard structures.
We're learning more about the natural features.
But we really don't know a whole lot
about how we combine these.
NARRATOR: For now the Corps is focused on brown-- pumping sand,
nourishing beaches,
in the Rockaways and on the Jersey shore.
It's tried and true protection.
VIETRI: We've only basically been looking at soft solution sets,
basically sand on a sandy beach.
Enough to buy us some time to take a deep breath
and look at what those more complex solutions might be.
NARRATOR: Most experts believe that ultimately,
soft measures alone won't be enough
to stop a storm like Sandy
from taking an enormous bite out of the Big Apple.
Less than a year after the megastorm hit,
New York Mayor Mike Bloomberg released a $20 billion plan
to make the city more resilient.
The plan calls for several small storm barriers
at strategic locations, as well as plenty of new sea walls.
And instead of a giant storm surge barrier,
Bloomberg sees new developments like this as the best defense--
Arverne by the Sea on the Rockaway peninsula.
Homes here were raised nine feet above grade,
with a robust stormwater drainage system.
They sustained minimal damage during Sandy,
a stark contrast to what happened nearby.
ORFF: To me that's the idea of resiliency.
We can't keep the water out.
But if you can retrofit your buildings to be able
to get wet, in a sense,
but not be critically damaged during a storm event.
NARRATOR: This sea change in attitude--
accepting that sometimes you have to let the water in--
is exactly what's going on in the Netherlands.
The whole foundation
on which the water safety system is built
is really being subjected to a critical revision.
NARRATOR: The tide began turning in the mid-'90s
after some devastating river flooding.
At the same time, scientists were issuing
increasingly dire warnings about climate change
causing both sea level rise and more rain in the region.
HANS BROUWER: It meant that the expectation is higher river peaks,
but also sea level rise.
And that would give a problem,
because the rivers flow freely into the sea.
So when the sea level rise, it will be much more difficult
to let the river water flow into the sea.
NARRATOR: The Dutch government launched a program
called Room for the River.
At the most flood-prone locations in the country
they asked property owners to leave, buying them out,
so the dikes could be moved inland.
So when flood waters come, they will flow onto empty land
without damaging homes or businesses.
Now we were talking about giving back land to the river system.
And that was quite a step.
NARRATOR: It is not just farmland making the room.
In the city of Nijmegen, they're reshaping the landscape
to make some space for the River Waal,
bulldozing a peninsula, leaving just a small island.
After many centuries of performing a sort of alchemy,
turning water into land,
the Dutch are facing the limits of their sorcery.
Not everyone everywhere can be kept safe from the water.
Is this the beginning of a tactical retreat?
METZ: The Dutch don't see this as a retreat.
They see it as a form of accommodation.
Now we're moving towards an approach in which
water is seen as perhaps not a friend but a "frenemy,"
somewhere in between.
NARRATOR: In Rotterdam,
where parts of the city lie 22 feet below sea level,
the Dutch are going even further,
coming up with innovative places to put flood waters.
DANIEL GOEDBLOED: We don't have room
in the city of Rotterdam to just add more canals.
So we have to think of other things.
And that's one of the things we're doing here,
is we're storing it actually underground.
NARRATOR: When a museum built this underground parking garage,
the city added on
a 2.5-million-gallon holding tank.
About ten times a year, heavy rains prompt them
to open the valves and fill the tank.
It prevents flooding and stops untreated sewage
from flowing into the harbor.
The city is also creating public plazas
that are walled and tiered
so they can double as retention ponds.
When it starts to rain, I mean, this fills up,
and all these terraces fill up, and kids just love it.
I mean, they put on their boots and they just run through it.
NARRATOR: Another more elaborate one is under construction
near a high school.
When it rains here, the playing field will fill up
and hold water until the pumps and sewers can handle it.
Keeping their feet dry has always been a Dutch priority.
But the key lesson they've learned over the years:
simply fending off the water as if it were a mortal enemy
is like tilting at windmills.
Whatever New York does, its defenses could be challenged
sooner than expected.
Because not only is sea level rising,
but future storms could be more destructive.
When megastorm Sandy hit the Northeast,
many asked whether this monster was the product
of climate change.
SHEPHERD: It's not clear to me
that this storm was caused by climate change,
but I think that we are in an era
where climate change is likely increasing the risk
or probability of certain types of extreme weather events.
NARRATOR: Climate models suggest that overall,
the number of hurricanes might go down.
But the ones that do form could be even more powerful
than they are today.
What all the models and theories seem to agree on,
at least globally at this point,
is that the frequency of the very high intensity,
Category 3, 4, 5 events, should go up.
NARRATOR: Hurricanes are giant heat engines,
fueled by evaporation from the warm surface of the ocean.
Once a hurricane gets revved up,
a warmer climate means more evaporation
and a stronger storm.
EMANUEL: If you look at the most powerful hurricanes
on the planet, they have winds near the surface
of about 200 miles per hour.
It's conceivable that a hundred years from now,
the top ranking hurricanes will have wind speeds
of, say, 220 miles per hour, about a ten percent increase.
NARRATOR: That may not sound like very much,
but as wind speed increases,
the potential for damage rises exponentially.
EMANUEL: So you're talking about something
that's half again more damaging than current hurricanes.
That's what we worry about.
NARRATOR: Bigger storms.
Higher seas.
Is a retreat from the water inevitable?
JACOB: In many places,
it will be absolutely inevitable.
Florida is doomed.
Not today, not next year, not next decade.
But 200 years from now, there will be one big swimming pool.
NARRATOR: So does it make sense to invest in expensive projects
like beach renourishment year after year
to protect a way of life that may not be sustainable?
VIETRI: It makes a lot of sense
to put sand on the beach in Rockaways right now.
But I would not suggest to you that 30 years from now
or 35 years from now that that might still make a lot of sense.
NARRATOR: And does it make sense for federal taxpayers
to subsidize flood insurance, an incentive for people
to build and rebuild right on the water's edge,
in low-lying parts of New Jersey,
where 30,000 businesses and homes
were damaged or destroyed by Sandy?
Or in Broad Channel?
Premiums here have skyrocketed.
Dan Mundy worries it could be a mortal blow to his community.
MUNDY: These are workers that you're talking about.
These are people who get on the A train.
They go to work every day.
They make $80,000.
They make $90,000 a year.
They can just about afford
to pay their mortgage and whatnot,
and you bring these increases in on them,
that's going to be a problem.
NARRATOR: Not an easy problem to solve.
And it's just one of many dilemmas
in the wake of megastorm Sandy.
MUNDY: When we got our back to the wall,
America can respond.
And this thing is so big,
and it's going to affect so much,
and it's going to affect so much of the economy
of the United States,
that this is the game changer, right here.
We have an opportunity after these big events
to really think broadly.
We shouldn't waste those opportunities.
Because there's an event bigger than Sandy out there, I'm sure.
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Captioned by Media Access Group at WGBH access.wgbh.org