Hurricane Katrina was a devastating "doomsday storm" that exposed critical failures in New Orleans' flood defenses and highlighted the increasing threat of more intense hurricanes due to rising global ocean temperatures.
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Her name is all too familiar. Katrina,
the storm that ravaged New Orleans. You
always hear about the doomsday storm.
Well, this was it.
She left in her wake around 1300 dead,
hundreds of thousands homeless, and one
of the most vibrant cities in America,
drowning and nearly destroyed.
Wherever she went, she was going to have
an impact. This was a large, powerful hurricane.
hurricane.
In Katrina's wake, there are also
questions. With improved hurricane
forecasts, was the storm a predictable
disaster? Who knew? We were pretty
convinced that it was just a matter of
time. I knew I was right. I knew that it
could happen. And who refused to listen.
We had a number of officials who
Almost surrounded by water, the city is
protected by levies and walls. Were
these overwhelmed by an unprecedented
storm or simply not up to the job? The
concrete structure would just push
laterally like the blade of a bulldozer.
Who would ever think the levies would
fail? It's just something I never in my
wildest dreams thought I would ever see
With more violent hurricanes predicted,
is Katrina a taste of what's in store
for the future? This season has taught
us that we have better be ready for
intense storms.
We can protect ourselves, but only if we
understand the storm that drowned the
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[Music]
you. It looks like an ordinary day in New
Orleans. The city is just awakening and
it's business as usual.
Africa Brumfield, a resident of the
walk. Walter Maestry, an emergency
manager, is on his way to his office at Jefferson
Jefferson
Parish. On the Gulf Coast northeast of
the city, Lisa Monty has dropped in at her
her
neighbors. Things seem calm, but there's
At the National Hurricane Center in
Florida, the meteorologists are busy.
It's hurricane season and there's a
storm called Katrina approaching with
New Orleans in her
sights. Max Mayfield heads the hurricane
watch team. Katrina formed from a
tropical wave that had moved off the
coast of Africa and then it developed
into a tropical depression. I believe
that Katrina has all the makings of a
killer storm. Alert for threats to his
parish. Walter Masonry called it
arrived. The wind started shaking the
facility pretty good at that point.
There was water and it never stopped
coming in.
There was water from here all the way
that way to the Superdome and then all
canal. You're sitting there and you're
wondering how are you going to stay
I have nothing. Nothing.
Yeah. Very, very hungry. We haven't
eaten in 3 days.
Would you please, please help us? [Music]
[Music]
It's a year before Katrina hits and
Hurricane Pan is striking New Orleans
winds. Floodwaters are surging into the
city. But fortunately, this hurricane is
The fictional hurricane Pam was created
by Ivra Vanhiran in his supercomput
using data from past storms, wind, rain,
and storm surge.
What became very clear to us was that
even a slowmoving category 3 storm would
totally flood New Orleans.
This computer simulation was the focus
of a 2004 disaster exercise held in
Louisiana's capital, Baton Rouge. This
was attended by about 300 people from
the federal level, from the state level,
and they sat together for about 8 days
and discussed some of the major issues
that they would face if there was a
catastrophic hurricane that struck New Orleans.
Orleans.
The simulation showed New Orleans would
be devastated.
61,000 people dead, over 175,000
homeless. On the surface, participants
seemed to take the exercise seriously. I
think everyone involved, particularly on
the local level, understood what we were
dealing with, understood what the
various roles were, who was going to do
what, where, when, and how. But
underneath there was skepticism. At the
Hurricane Pam exercise, we had a number
of officials who basically scoffed at
us. Would the lessons from the PAM
simulation be heeded when the real
[Music]
along? It's over a year after the
Hurricane Pam exercise and the 2005
hurricane season has begun.
Thunderstorms are brewing off the west
coast of Africa. One of these will give
birth to Katrina. What the thunderstorms
do is they draw heat from the ocean
surface. That's the driving mechanism
that produces hurricanes. [Music]
[Music]
Katrina begins as a small storm called a
tropical depression, a center of low atmospheric
atmospheric
pressure. In the warm waters of the
eastern Atlantic, water vapor rises from
the ocean than cools, forming clouds and
releasing heat energy, which fuels the
storm. This sucks in more warm air,
generating strong winds which shoot upwards.
upwards.
When this rush of air hits the
stratosphere, it flattens out and
influenced by the Earth's rotation, the
storm starts turning
counterclockwise. As soon as the winds
reach 39 mph, the depression is
considered a tropical
storm. This is Katrina 6 days. Large,
A day later, there's bad news. The
hurricane center has upgraded the
storm. Roughly half of all tropical
storms become hurricanes. So, the team
generates computer models to forecast
In 2004, more than a third of the
population of New Orleans evacuated for
Hurricane Ivan, unnecessarily, as it turned
turned
lives. Hurricane forecasts are improving
due to a greater understanding of
atmospheric dynamics and more extensive
satellite coverage.
We rely very heavily on remote sensing
via satellites and we have various
satellites in which we do that. But the
team needs more data than even
provide. So as soon as tropical storm
Katrina is within range, they send out
the Air Force hurricane
hunters. Their mission to fly right into
the approaching storm. As the pilot
battles extreme turbulence, external
sensors record wind speed, pressure, and
temperature to build up a more detailed
picture of
Katrina. And a new piece of technology
has been added to the hurricane hunter's arsenal.
arsenal.
This is the drop. It acts much like a
weather balloon, collecting temperature,
relative humidity, and also pressure.
There's also a GPS module that will be
affected as it shifts from one point to
the next. That will give us our wind
direction and wind speed.
The sand is released through a chute in
the floor. And then as it floats down to
the surface, it's radioing back all that
data. As the sand is tossed about, its
GPS unit feeds back its position,
relaying wind speeds at many different
points in the
storm. Clearly, Katrina is building.
During this one flight, wind speeds have
increased to 59 mph.
force. This data is fed to the hurricane
cent's supercomputers, which generate a
prediction cone, where a black line
shows the 5-day forecast of the
hurricane's likely track. The hurricane
is steered by zones of high and low
atmospheric pressure surrounding it.
These constantly shifting weather
systems make track forecasting
incredibly complex. But in recent years,
the team has made huge advances. We've
got a real success story here. The
observations are indeed better. The
computers are faster and and the
computer modeling is much improved. So
now our 5-day forecasts are exactly what
our 3-day forecasts were just 15 years ago.
But intensity is much harder to predict
than track because the inner storm can
change minuteby
minute. Katrina is still only a tropical
storm. The key question is will she
hurricane? Well, here in the United
States, uh we categorize hurricanes as
category 1 through five with five being
the worst.
At the bottom of the scale is a category
1 with wind speeds of up to 95
mph, causing damage to trees and
branches. Category 2, the hurricane has
winds of up to 110 mph, enough to punch
the air out of your lungs. When the wind
speeds hit 130 mph, the hurricane
becomes a category 3.
At category 4, roof tiles are peeled off
and houses will sustain structural
damage. Category 5 is the most feared
with winds of more than 155 mph. Whole
destroyed. But hurricanes deliver a
deadly double blow. Not just high winds,
but a massive bulge of water called the storm
storm
surge. The high winds push down on the
ocean surface, causing the water to rise
like an unnaturally high
tide. This wall of water is so dangerous
that 90% of deaths in hurricanes come
[Applause] [Music]
[Music]
On Thursday the 25th of August, Katrina
finally grows into a category 1
hurricane. She has formed an eye and is
heading straight for southern
Florida. Less than 2 hours later, she hits
hits
land. With no warm water to fuel her
fury, Katrina dies down. But there's
more warm water ahead in the Gulf of
Mexico. In New Orleans, Walter Maestry
watches the storm track nervously. He
knows from near misses like Hurricane
George in 98 and Ivan last year how
is. New Orleans lies between two
potential flood waters. the Mississippi
to the south and Lake Poncha Train
connected to the Gulf in the north. The
metropolitan New Orleans area is a bowl.
It looks like a gigantic soup bowl. We
exist on average some 7 to 10 ft below sea
[Music]
level. When the Mississippi flooded
every year, it deposited silt to create
vast boggy marshlands.
The city itself was built on the only
natural high ground, which would become
the French [Music]
[Music]
Quarter. Joe Sueda is a coastal engineer
who studies the city's
defenses. The city was established at
around uh the year 1700 and it was
established on high ground that was
adjacent to the Mississippi River. And
uh this high ground was not flooded annually.
annually.
Surrounded by
marshlands, New Orleans couldn't grow
until an engineer named Baldwin Wood
designed a complex system of pumps and
drainage canals to dry the
city. Much of the system is still working
working
today. And with the floodprone areas
dry, New Orleans expanded outwards from
wetlands. But this created a bigger problem.
problem.
In order to settle the areas, you got to
drain the water out of them. Well, as
those soils then become drained, the
organic matter breaks down just like
compost. And so you lose bulk and the
The shrinking soils caused the city to
sink further. To protect the growing
population, the state built earthn
But in 1927, the Mississippi burst her
banks in a catastrophic flood that
killed at least 500 people and swamped
more than a million
homes. Although the flood never reached
New Orleans, the authorities dynamited a
precaution. The resulting man-made
flood, drowned two of the poorest
parishes, and displaced some 10,000 of
And it was a turning point as the Army
Corps of Engineers took control of the
levies. From that point on, the core of
engineers and the federal government
have had a large part to play in the
levies, especially the Mississippi River
levies in the city of New Orleans and southern
southern
Louisiana. Colonel Richard Wagenar is
now in charge of a,200 strong team. It's
their responsibility to build and repair
the levies to protect against hurricanes like
like
Katrina. New Orleans has two types of
levy. The original earthn levies and
more recently built concrete and steel flood
walls. It was after Hurricane Betsy in
1965 that Congress set standards for the levies.
levies.
Betsy was a category 3 hurricane,
flooding. Since then, Congress has
provided the Army Corps of Engineers
with funds to upgrade the levies to
withstand a category 3 and no more. A
lot of the construction on current day
construction was in the 60s. The flood
walls were all finished early 90s. The
system we were working on was a system
to withstand a fastmoving category 3.
But with Katrina growing in the Gulf,
would category 3 levy protection be enough?
Hello, Walter. How's it going there? On
Friday the 26th of August, Walter
Maestry receives a worrying phone call.
The week that Katrina made landfall, I
got a phone call from Max Mayfield, the
director of the National Hurricane
Center. I called Walter Maestry, who is
the director of emerge management in
Jefferson Paris, Louisiana, and I told
him, Walter, you better get ready. You
got to know Max Mayfield. He's an
extremely low-key individual. Uh, not
much upsets him. When you get that phone
call from Max, it's serious.
For Walter Maestry, it's the news he's
been dreading. The National Hurricane
Center shows the storm heading straight
toward the Gulf Coast west of New
scenario. Since a hurricane spins
counterclockwise, it generates stronger
winds and more pressure on its eastern
flank. So, the storm surge to the east
is also more severe, directly
threatening New Orleans.
With so many of its neighborhoods below
sea level, New Orleans is going to need
defenses. Those defenses used to be
wetlands. Before its levies were built,
the Mississippi River conveyed tons of
silt and soil to the coast each year.
Every spring when the river flooded, the
wetlands were strengthened and replenished.
These wetlands protected New Orleans
against hurricane storm surges, soaking
up the violent waters like a sponge,
while stands of cypress trees acted as a
windbreak. But when leveies were built,
they kept the river from flooding.
The wetlands became starved of new soil
rate. Sheay Penland is a coastal
oceanographer who has witnessed this
decline for over 30
years. It's creeping up on us. It's it's
occurring every day. The land's washing
away every day. It's chronic.
The depleted wetlands are more
vulnerable to the encroachment of salt
water from the Gulf, which kills most freshwater
plants. Louisiana's wetlands are
vanishing at the staggering rate of at
least 20 square miles a year, nearly a
And as wetlands disappear, storm surges
rise, putting New Orleans at even greater
greater
risk. We dodged a bullet with Hurricane
Andrew in
1992. We dodged a bullet with Hurricane
George in
1998. And we dodged
But would New Orleans dodge the bullet this
time? At Louisiana State University,
Ivor Vanhiran and his team take what
they know about Katrina and put it into
the same computer model they developed
for the disaster exercise called
Hurricane Pam the year
before. Hassan Mashri is the man
inputting the data. From the beginning
we saw that uh hurricane Katrina was a
very uh very deadly storm. It would
start to flood the lower parishes and as
it became stronger and stronger it
started to indicate that it's going to
flood the city.
Vanhiran takes the news public sending
email after email to officials in charge.
charge.
We knew on Saturday night that this was
the big one, that it was going to sink
New Orleans and uh so we tried to get it
the word out as much as possible. CJ
Walter Maestry is desperately trying to
get people to leave his parish. It was
fairly obvious that um this was going to
be a storm that was going to land in our
backyard and uh we need about uh between
60 and 72 hours to get those who are
willing to evacuate evacuated and that
therefore we were going to have to move.
But surveys conducted earlier indicated
that not everyone would be willing or
able to evacuate. We understood that
about 68.2% 2% of the people would
leave, which would have meant about
300,000 would have stayed. Many people
have no
transportation. But Lisa Monty, who
does, decides to
stay. She lives in Bay St. Louis on the
Gulf Coast 60 mi from New Orleans. She
rode out one of the worst storms to hit
the coastline, Hurricane Camille, in 1969.
Camille didn't get us. We stayed here.
Uh, it was a very long night. The wall
shook, the floor shook. We we had to
scream. The wind was so
loud, but the water from the beach
Camille. In her house, set back from the
beach 20 ft above sea level, Lisa Monty
assumes she is safe from
Katrina. And in the heart of New
Orleans, Africa Brumfield, with her
house 12 ft below sea level, decides to
remain as well. Some of our family
members decided that they would leave,
but my parents decided to stay and I
wasn't going to leave them and go to
safety. So, I decided to stay with them.
But Max Mayfield and his hurricane watch
team keep making frantic calls to warn
of the impending danger. with that type
of event. I want to be able to leave the
National Hurricane Center that night
knowing that I done everything that I
[Music]
Jeff, we're going to start with you
again. Of course, New Orleans under a
hurricane warning and now it has been
bumped up to category 5. The Army Corps
of Engineers is evacuating most of its
staff to be on standby, safe from the storm.
storm.
We have a plan for a team to remain
behind in New Orleans. Uh, an eight or
nine man team in a bunker that's
certified for a category 5 storm.
Perry Lig is one of the men who stays to
monitor the levies.
And this is the bunker. This is the room
that we man the phones from the EOC
office. There was eight of us with
Colonel Wagner.
Walter Maestry decides to evacuate most
of his personnel. We get to a minimum
staff very quickly, implement what we
call our doomsday procedures and uh and
make sure that the fewest possible folks
are at risk. Ladies and gentlemen, the
mayor issues the city's first ever
mandatory evacuation. Every person is
hereby order to immediately evacuate.
But for Ivor Vanhiran, armed with his
prophetic knowledge, desperation is
setting in. I knew we were going to lose
a lot of people. I knew there was going
to be super devastation. I knew there
would be thousands of families who would
lose their livelihoods, lose their
homes. I knew that we were going to see
an awful amount of heartbreak.
The city streets are all but deserted.
Those who have remained are inside
ahead. The small contingent from the
Army Corps makes hourly visits to check
the height of the Mississippi.
We're reading gauges and from about 3 or
4:00 in the evening Sunday evening till
the last gauge I went out and read was
at 10:30.
Though the hurricane has not yet made
landfall, the river has risen 11 ft.
Around 10:30 or 11, the wind starts to
get more and more rough. The Army team
is forced to retreat to their steel
reinforced bunker and watch as Katrina
We kept looking out the front door port
hole watching the wind blow, but we we
felt safe. Outside, stormchasers are
experiencing the storm's dramatic
Around midnight, it got really bad. It
was blowing to the point where the house
would shake. Not a lot, but it would
move. And you knew something was
different about the way the wind was blowing.
blowing.
It was very cramped. And of course, the
adrenaline is very high. We've never
been in the bunker for a hurricane. The
wind wasn't rattling and just moving and
shaking. It was banging like a bulldozer
beating against the wall. It would just
hit. Boom. Boom.
The house was shaking. It sounded like
the walls were trying to just fall
apart. And it was it was a scary
feeling. And I started to feel like I
At 6:10 a.m., Katrina strikes land. The
National Hurricane Center has amazingly
predicted her track to within about 20
m. She has now veered to the east of the
city, avoiding the worst case scenario,
but there is no escaping Katrina's devastating
power. Watching events from Baton Rouge,
Ivor Vanhiran and his team are
especially concerned about the levies on
the eastern side of the city. We felt
the levies could be overtopped. During
Hurricane Betsy, we had lost significant
amounts of levies, especially on the
Industrial Canal, and our fear was that
the same thing was going to happen
again. The eastern sections of New
Orleans are bordered by the Industrial
Canal and the Inter Coastal Waterway,
which connects to the Gulf. Katrina's
storm surge would fire like a bullet up
the inter coastal waterway toward the
heart of the city. But if it happens, no
officials will know. The Army Corps of
Engineers has no external monitoring
equipment. While the power lasts, the
engineers rely on the media. Trina has
made landfall. Now,
we had a lot of reports, people calling
in and reporting things wrong with levies.
levies.
Despite the confused nature of the
calls, it is becoming clear that
something has gone wrong with the levies.
levies.
At about 7:00 a.m., a massive storm
surge charges into eastern New
Orleans. A 15 ft wave is funneled up the
inter coastal waterway and smashes into
the industrial canal like a runaway
train. The earth and levies around the
canal are first overtopped and then
scoured away by the force of the
water. Hit immediately are New Orleans
East, the lower 9inth ward, and the
upper ninth. Residents of these poor and
working-class areas had been warning for
surge. The water rushes into the lower
9inth ward and St. Bernard Parish at incredible
speed. 77year-old August Hubard had
taken shelter in a small hotel in the
lower ninth, but a 10-ft surge of water
floods the building within minutes.
A Navy veteran of Korea and Vietnam, he
finds himself swimming for his life. The
water was up to my chest, but I took and
stumbled and went down and the water was
up to my up to my mouth almost. They
might have snakes, they might have
alligators, they might have anything in
the water. And we could see like some of
these gas pipes and I could see like
streams of bubbles coming up and that
was gas.
As in the great flood of
1927, the poorest districts suffer
most. People are left to fend for
themselves as the water
yet. At around 10:00 a.m., Katrina makes
landfall again near Bay St. Louis and
Gulfport, 35 mi northeast of New
Orleans. Here on the dangerous eastern
side of the eye, the storm surge is a
[Music]
ft. Recorded by
stormchasers, houses and cars are swept
away by the incoming
water. In Bay St. Louis, Lisa Monty,
supposedly safe on high ground, is
stranded on her upstairs balcony.
The water had raced down the street and
was filled the yard and all the debris
as it came in. The building shook and
rocked so much that I didn't know how
long it would stand. Let's go. Come on.
Come on. All along the coast, entire
communities are wiped
out. Back in New Orleans, confusion
reigns. Electricity is off. Landlines
and cell phone networks are
down. With communications decimated,
city officials and emergency teams are
unaware of the extent of the damage,
Ward. By early afternoon, Katrina is
moving inland, progressing north and
gradually weakening. When the storm left
and started to move to the north, we
felt blessed because it appeared that
Katrina had not been uh you know as
devastating as we thought. But they
couldn't be more wrong. A second huge
flood has already hit the
city. Around 2 p.m., Colonel Wagenar and
his engineers finally head downtown to
check on vague reports of damage to the
drainage canals at London Avenue and
17th Street. There was a civilian that
had told us that there was a over
topping or something wrong with the
wall. But over a mile from the 17th
Street canal, they are stopped in their
tracks. We could not get any closer. We
encountered significant amounts of water
at what we call the I 10610 split on the
interstate highway. um probably 10 to 15
feet of water. I knew at that point that
that was much more water than had come
down from
rainfall. The 17th Street and London
Avenue canals burst in three major
locations sometime around 10:00 a.m.
Throughout the day, water from Lake
Poncha Train pours at high pressure into
The city's huge pumps, only designed to
deal with rainfall, are no match for the rising
rising
water. Nothing can be done to stop the
water gushing in through the gaping
breaches in the two canals. One of the
problems is that the system is designed
to keep the water out, but there was no
provision really for managing the water
once it got inside the city.
There wasn't a specific plan um to fight
the floods if a flood wall failed. We
had a plan from the organizational
perspective, but not specifically to
wall. As the afternoon progresses, water
continues to pour into the
city. The New Orleans bowl is filling up.
Africa Brumfield's home is downtown near
the London Avenue Canal, right in the
path of the second flood. I sat outside
from about 3 when the water started to
come in until maybe 7:00 that night
watching the water rise from the ground
and it continued to rise and it
continued to rise. So, we went into the
house and we figured it'll stop. So, I I
tried to lie down and go to sleep, but
who can rest in situations like that? It
was getting dark and that night we
returned to the district um and just
hunkered down for the night. Uh there
was only still the nine of us um and
waited for the next morning to get back
By nightfall, the water is still rising.
But with communications out, many in the
sleeping city are unaware of the danger.
We could have got uh vehicles driving on
the interstates with bullhorns telling
people we even could have used
helicopters with bullhorns. We could
have warned the people the big floods
coming, take evasive action. We didn't.
People went to bed on on Monday evening,
houses dry, and woke up in the middle of
the night with water up to their waist.
I got up around midnight and it was
still rising in the house. And my house
sat up about 4 feet off of the ground.
And I was thinking, if my house is 4t
off the ground and the water is in my
house, I'm only 5'1 and it's in my house
about 2 ft. There's no way that I'm
getting outside without going for a nice swim.
As dawn breaks on Tuesday, the extent of
the damage is becoming clear. There are
multiple breaks in the leveies. Two
major ones on the industrial canal that
flooded the 9inth ward to the east and
three on the 17th Street and London
Avenue canals which filled up the
central city
bowl. 75% of greater New Orleans is now
underwater and it is still full of
people. Rescue teams are massively
overloaded. For more than half a
century, no US hurricane has affected so
many. We worked from probably 5:00 all
through the night without stopping into
the next night.
We grabbed air mattresses and pots
because we needed something to paddle
with. And we got in the water and we
started to paddle on the air mattresses
with the pots. People are screaming,
"Help us. Can you please help us?" I
sent two of my really good friends back
and they saved a lot of elderly people
that really couldn't walk or move and a
lot of little children. I was bringing
out at least 50 people per run and I
made runs for a week solid. I was worn
out. You always hear about the doomsday
storm that they've been predicting for
100 years to hit the city. Well, this
was it.
When the water finally stops rising in
the flooded city, work can resume on
fixing the flood
walls. With roads and canals blocked,
the Army Corps of Engineers is initially
So that's a Chinook helicopter. It's a
medium lift helicopter and there are
three should be three sandbags
underneath that and it is reinforcing
one of the sites that was breached on
the London Avenue Canal. So underneath
all of this rock and gravel are sandbag.
Well, you can see them right here.
Sandbags just like that. So they're
flying over to that brereech uh dropping
the sandbags and building up the height
of that wall that's stopping the water
from moving from the canal uh to the
flooded areas.
Eventually, the breaches are filled and
the water begins to be pumped out, but
it will take over a month before the
city is dry. In the meantime, rescue
efforts continue. Hundreds are pulled
from their wrecked homes. 77year-old
August Hubard from the lower 9inth ward
spends a freezing night after swimming
to an overpass until a helicopter
finally picks him up. The helicopters
kept passing and waving at us. They put
me in the hospital. I stood in the
hospital three and a half days cuz I had
a diarrhea and they checking my heart
and stuff like that. Well, they brought
me to an airplane hanger and they had
like about four or five thousand people
in there and we were sleeping on mattresses.
mattresses. [Music]
The chaotic official response means that
there is still no food or water
city. For many, there is no way out.
civilization is breaking down around them.
them.
We passed a lady in a hospital bed being
pushed on the interstate and all of a [Music]
[Music]
sudden reality hits you of where you are
The rescued and displaced are told to
head for shelter at the Superdome and
the convention
center. In a story that's all too
familiar, many are forced to wait in
squalid conditions for
days. All around them, the city lies in
ruins. 60,000 houses in New Orleans and
other communities are eventually
In New Orleans alone, over a thousand
lives. It's just something I never in my
wildest dreams thought I would ever see
or could ever happen. Who would ever
thought a 100,000 people, you know,
hurricane? I guess the reason they
stayed is who would ever think the
So, was the damage and loss of life
avoidable? Why did the levies
fail? In the wake of the storm,
questions began to be asked, and they
focused on the height of the storm
surge. On the Gulf Coast, Bay St. Louis
was on the dangerous eastern side of the
eye when the surge hit.
Lisa Monty's town experienced the
maximum 28t height of the surge. You
could see how massive
the wall of water was that climbed up
and did all of this
destruction. As far as you can see on
either side of the beach there really
there is
nothing. I've heard so many workers who
are from out of town say, "I can tell
that this was a special place. [Music]
New Orleans was on the less powerful
western side of the
hurricane. Still, a wave of 18 to 25 ft
shot up the inter coastal waterway and
along the industrial
canal. It overtopped the category 3 levy
walls by more than 5 ft, scouring away
their foundations and pushing them aside.
aside.
It became clear that overt topping was
the main reason the levies had failed
around the lower 9inth
ward. But the breaches that flooded
downtown New Orleans were more difficult
to figure out. By the time the storm
surge reached the 17th Street and London
Avenue canals, its height was much
lower. In theory, the flood walls along
these two canals should not have failed
like the overttopped levies of the
industrial canal to the east.
The water never got within 2 ft of the
top. The London Avenue and 17th Street
canals did not experience category 3
conditions. They experienced conditions
of a category 1 or category 2 storm. So
the design criteria weren't exceeded. So
if they weren't over topped, why did they
they
fail? That is the subject of a major
engineering investigation.
We're right now at the northern end of
what is called the 17th Street Canal uh
right at the uh lake
shore. That's the brereech. That's
ground zero as it was called. As with a
boat, all you need is one hole and the
whole boat can sink. This actually was
the weak link in the chain. But the
problem lies deeper than the concrete
flood wall itself. Joe Sueda is looking
for evidence to support his theory that
the walls were not overtopped but undermined.
undermined.
Now, was this dirt always here? This
hill? Yeah, but it was not here. It was
See, that's what we
suspected. This area was as we suspected
about 30 ft closer to the water and the
movement of the earth which went
sideways actually lifted the house up.
That's exact. That's correct. It's
amazing. That's amazing. The flood walls
had undergone what engineers call a
pressure burst. They were undermined by
their own foundations, soft pey soil, no
match for the force of the water. This
is what we had suspected in terms of the
mechanism of failure was uh that the
flood wall failed at the base. the earth
was too weak and the the sheet piling
itself and the monolith, the concrete
structure, were just pushed laterally
like the blade of a bulldozer.
Evidence suggests that the flood wall
failures could have been prevented if
the pilings had been driven more deeply
into the ground.
What is now very obvious is that these
walls were underdesigned, undergineered.
There was basically a catastrophic
structural failure of those levy
systems. The Army Corps of Engineers
plans to repair the leveies up to
category 3 by next hurricane
season. But the flood wall failure has
called into question the reliability of
the entire levy system, just at a time
when it may be needed more than
ever. 2005 turned out to be the busiest
hurricane season on record. Katrina was
swiftly followed by Rita, causing more
damage to the Gulf Coast. Stan smashing
into Central America and Wilma
devastating Mexico and Florida.
Meteorologists have now run out of
letters in the Roman alphabet. Moving on
to the Greek. The first ever hurricanes
recorded. For decades, scientists have
understood that hurricanes come in cycles.
cycles.
We think here at the National Hurricane
Center that uh hurricane activity is
cyclical and you'll have uh some active
periods followed by inactive periods
followed by active years again. And in
fact in the 40s 50s and 60s were very
active in the Atlantic basin. The 70s
80s and early 90s very inactive. And
then 1995 we really became active again.
But some scientists believe that cycles
alone do not explain the increase in
powerful hurricanes.
Studies of global hurricane activity
over the last 30 years have shown that
although hurricane frequency seems
unchanged, the average intensity has
increased. The number of category 4 or
doubled. Peter Webster believes this is
linked to rising ocean temperatures all
over the world. The bottom line of of
our study is that we find a consistency
between the increase of surface
temperature in all of the oceans and a
change in intensity to more intense
storms. Over the last 30 years, global
sea surface temperatures have climbed
about 1° F or over half a degree
centigrade. And this provides vast
amounts of extra energy for hurricanes.
One hurricane is equivalent of 100,000
power. In just one area, such as the
Gulf of Mexico, that small half degree
increase in temperature of the sea
surface is the equivalent energy of
about a million atomic
bombs. If you think of it in terms of
the fact that there's enough energy in
that half degree to generate an extra 10
strong hurricans, then you start to see
the size of the problem. Global warming,
the heating of the atmosphere often
associated with human activity has been
invoked to explain both the rise in
ocean temperatures and more intense
hurricanes. So, one is left in a sense
to the greenhouse gases increase as
probably the reason that we're getting
the sea surface temperature increase.
Uh I think that's been studied and uh I
think that most reasonable scientists
will make that association. But not
everyone agrees.
A lot of people ask about the
relationship between hurricanes and
global warming and that's certainly a
fair question. Uh we think that
hurricane activities can be explained
without invoking global warming. But
scientists do agree that things are
going to get worse before they get
better. The bad news here is that the
research minologists tell us that this
active period that we're in uh could
very well last another 10 or 20 years.
So my message there is uh no matter what
we're in this active period and we need
prepared. With its defenses found
wanting, New Orleans will have to
struggle to be ready for the next assault.
assault.
All indications are that the levies and
flood walls are not up to the job of
protecting the city, even from a
category 3 hurricane. There is no money
to upgrade them, even though more
category 4 and fives are
expected. Category 3 protection was not
adequate. It's clear to me that if we're
going to re build a city that it uh has
to be built upon a basis of category 5 protection.
protection.
It clearly would have made sense to
protect and and avoid the federal
government spending the hundreds of
billions of dollars by investing an
additional, let's say, $2 billion in levy
protection. But levies are not the only
way to protect a sinking
city. More radical options are now on
the table.
Much of the city is below sea level. I
think uh given the opportunity in
situations like it's over my shoulder
here where the area will have to be
completely demolished that we rebuild
those and basically invert the bowl,
bring sediments in to raise the ground
perhaps up as high as we're standing
right now. But preventing further
destruction of the environment may be as
effective as any ambitious rebuilding
scheme. The ultimate key to uh
Louisiana's survival and reducing the
impacts of surges is to restore our
coastal wetlands. These wetlands uh
knock down the surge and they also
reduce wind energy as as the storms pass
over them.
After nearly a century of building
levies to control the Mississippi, one
idea is to let parts of the river run
wild once more. This plan would create a
new tributary that would be allowed to
flood, deposit silt, and rebuild the
wetlands. This would cost billions and
take as long as 50
years. But just as difficult may be the
task of rebuilding the confidence of the
people of New Orleans. Both the disaster
and the long, slow process of rebuilding
have convinced many not to return.
This was home. And I've been all over
the world thanks to the military.
Nothing ever felt like New Orleans
ever. But I can't come back to live.
Going through that again is too scary.
For those who had long predicted this
calamity, all the attention now being
given to hurricane protection has
brought no contentment.
With around 1,300 dead and 800,000
homeless, the price has been far too
high. It's hardy to say it, but I knew I
was right. I knew that it could happen.
Uh it's horrible that it did. And what I
see around me now on the faces of the
individuals who have lost everything and
don't know, you know, what's going to
happen to them. Um that's devastating.
That's the devastating part of it.
And for those scientists who'd seen
their warnings
ignored, it hits especially hard. You
know, I'm really heart saw for those
people. You walk past some of these
homes, only half of them are standing
because they've been destroyed by the
floods. They've lost so
much. So, so much. And I think that's
the the the really hard
part for me to take is I knew it was
coming and to go and see it day after
day is really [Music]
[Music]
[Music] [Applause]
[Applause] [Music]
Nova is a production of WGBH Boston.
Corporate funding for NOVA is provided
by Google. Major funding for NOVA is
provided by the Howard Hughes Medical
Institute, serving society through
biomedical research and science education,
education,
HHMI, and the Corporation for Public
Broadcasting, and by PBS viewers like
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