>> NARRATOR: More than a hundred
miles of highway across the sea... a freeway of spectacular
bridges, including one of the longest in the world...
an engineering feat once thought impossible.
A road like no other, through the paradise of the Florida
Keys. Now, "The Overseas Highway," on<i>
Modern Marvels.</i> <font color="#FFFF00">Captioning sponsored by
A&E TELEVISION NETWORKS</font> At the tip of Florida, in the
southernmost part of the continental United States, lies
the Overseas Highway. It is 119 miles long and begins
just south of Miami off the coastal edge of the peninsula.
It then winds its way in a southwesterly direction over the
Florida Keys and ends in the city of Key West.
>> LES STANDIFORD: Anyone who's ever been on the Overseas
Highway from Miami to Key West will tell you it's one of the
most amazing drives on earth, where you're really on a
spider's web of trail across the ocean.
>> NARRATOR: What sets this highway apart from other
roadways is that so much of it is over water, roughly 20%.
It features an astonishing 51 bridges.
Running parallel to several of these bridges are remnants
of a century-old railway. Today's modern Overseas Highway
owes its legacy to it. The old bridges are now used as
fishing piers and bike and foot paths.
Next to one these rail bridges stands one of the newest
structures on the Overseas Highway: Seven Mile Bridge.
The bridge is more than 35,000 feet long and spans 6.7 miles of
water. It is one of the longest of its
kind in the world and among the most spectacular.
Its tallest point is 65 feet high, allowing sailboats to pass
under. >> RICK McNEW: It gives me goose
bumps every time I drive over it.
It's-it's quite a structure. >> NARRATOR: The new bridge was
constructed in 1982 by Misener Marine Corporation and designed
by Figg Engineering Group as a "precast concrete segmental"
bridge. >> LINDA FIGG: The
superstructure of the bridge, or the top portion of the bridge,
is composed of precast segments that are in this shape, like a
box with a voided section. >> NARRATOR: A bridge-span is
the distance between two piers. On Seven Mile, there are 223
spans. Each is 135 feet long and
composed of seven 68-ton segments.
>> McNEW: The segments are match-cast which means in the
casting yard, you set your forms around the previously cast
segment, and you cast the new segment right up against it so
that you have a perfect match. So you want to cast them
together. >> NARRATOR: More than 1,500
segments were cast in a yard 450 miles away in Tampa, Florida.
From there they were barged directly to the bridge site.
On a manmade platform near the bridges, the segments were
assembled. Bridge workers threaded the
segments with thousands of feet of steel cable.
The cable was "post tensioned," that is, stressed and locked in
stress, so that the entire bridge span is in compression.
>> FIGG: This bridge technology in an earlier form was used in
Europe following World War II where a quick, cost-effective
bridge replacement scheme was needed to replace the bridges
that were destroyed after the war.
>> NARRATOR: A barge carried a span underneath the bridge.
It was lifted by a special overhead gantry and placed on
the bridge's concrete foundation piers.
>> FIGG: And you could build, with this overhead gantry system
and the precasting technique that was used, three spans of
completed bridge a week. >> NARRATOR: Workers completed
Seven Mile Bridge six months ahead of schedule in the summer
of 1982. It took two and a half years.
>> FIGG: This bridge was a great solution for this
seven-mile location because of its speed of construction and
cost savings. >> NARRATOR: The Modern Overseas
highway may have been completed in 1982, but the Florida Keys it
crosses over are millions of years old.
The Keys are actually hundreds of islands built up on the
skeleton of an ancient coral reef and surrounded by mostly
shallow water. Up until the early 20th century,
life in this region was rough, and travel options were limited.
>> JERRY WILKINSON: Well, it was totally by-by sea or by foot.
You either walked it, or you got in a boat, and you rode it, or
if you had the correct wind and a sailboat, you could... you'd
sail. >> NARRATOR: Except for a few
farmers and those who made their living off the sea, not many
people called this place home. >> STANDIFORD: There was nothing
in the Keys at this time, not in the middle Keys or the upper
Keys. These were bits of reef.
There were a few settlers, hearty settlers.
There was a lot of smuggling of one sort and another.
It was a-a wild and woolly place in those days, and very, very
few people living, maybe a couple hundred people, up and
down the Keys. >> NARRATOR: The exception was
Key West. Boasting 20,000 residents in
1900, it was bigger than Miami or any other city in Florida.
Deep sea fishing, sponge harvesting and cigar
manufacturing made it a thriving commercial center.
It was also a popular coal refueling stop for steamships
coming from South America and the Caribbean.
But life on the Keys was about to change irrevocably, thanks to
the vision of an oil baron named Henry Morrison Flagler.
>> STANDIFORD: I think a lot of people know who John D.
Rockefeller, for instance, is, but I don't think they know that
Henry Flagler was once the partner of John D. Rockefeller
and the brains, according to Rockefeller, behind Standard
Oil. >> NARRATOR: In 1870, the value
of Flagler's shares in Standard Oil was more than $125 million,
but his life took a dramatic turn when he fell for Florida.
>> STANDIFORD: Flagler was a lot like any other Midwesterner who
comes to Florida and looks around and sees the palms
swaying and feels that warm breeze off the ocean and says,
"A man would have to be fool to want to live anywhere else in
the world." He got seduced away from oil.
Actually, he got tired of it. He came down here with a second
wife on a honeymoon, fell in love, and began building hotels
and then railroads to service these hotels.
>> NARRATOR: They were luxury hotels with state-of-the-art
conveniences like bathrooms and running water in all rooms.
>> WILKINSON: He was really into hotels.
That was what he was after. But to support hotels, you
got to have your transportation system where people can get
to your hotels, and he proceeded to buy up every
railroad on the east coast of Florida.
>> NARRATOR: Flagler created the Florida East Coast Railway
Company, and New York's elite were soon traveling by rail to
vacation in Florida. His next venture would be
inspired by news in 1901 of a Panama Canal project.
Flagler reasoned that Key West would be the closest US port
to the canal. All he had to do was find the
best way to get cargo from Key West to the mainland.
He decided to build an "overseas" railroad.
>> MIKE LUMPKIN: At the time, some of his contemporaries
called it "Flagler's folly." He was told that he could never
build a railroad over open ocean.
>> NARRATOR: But Flagler would try.
If successful, coastal Florida would be linked to Key West for
the first time in history. No other roadway in the United
States is quite like the Overseas Highway-- linking so
many islands and traveling such distances directly above the
sea. And yet, the blueprint for this
remarkable modern highway was conceived in the minds of young
engineers born in the mid-19th century.
It was oil baron Henry Flagler's Florida East Coast Railway,
built in the early 1900s, that not only provided much of the
route of today's Overseas Highway, but also its
foundation. Most of the highway follows the
same path that was virtually hacked out of the subtropical
wilderness for the railroad. >> STANDIFORD: It was 153 miles
from Miami to Key West, much of it over open water, and what
isn't over open water was essentially swamp.
And railroad engineers debated whether such a thing could be
done. >> NARRATOR: Flagler thought it
best to go directly from Miami to the very tip of the
Everglades and then jump 30 miles south, straight across
open water to the Middle Keys. >> STANDIFORD: They sent out a
survey party, and they tracked across the Everglades and
immediately were lost. Drank all their water, ate their
food, were wandering, about to die, until they were discovered
by Indians, who were out in a hunting party, and led to
safety. And William Krome, who was the
man in charge of this foray, came back to Flagler and said,
"Forget the Everglades." >> NARRATOR: Flagler's engineers
settled on a route that would go from Miami to the town of
Homestead. The railroad would then jump
across to Key Largo and head southwest from there.
The plan was to use landfill to cross the shallow inlets between
Keys and build bridges to span waters that were too deep.
Flagler wanted to use as much landfill as possible, but
critics believed that blocking the channel between the Gulf and
the Atlantic Ocean would have negative environmental
consequences. >> LUMPKIN: The US government
told him that he had to leave six miles open.
He wound up leaving 17 open. So, there are 17 miles of
bridges and 20 miles of fill. >> STANDIFORD: So even in those
days, there were environmental concerns.
And then the practical concerns came.
How do you get a workforce down at the tip end of a country when
there are no people? And how do you get supplies when
you're hundreds and thousands of miles from sources of material?
>> NARRATOR: Flagler brought in all equipment, construction
materials, fuel, food and labor by steamship and rail.
His vision was strong and his pockets were deep.
At one time, Flagler had under contract every available
steamship on the East Coast of the United States.
Even barrels of water were imported-- other than rainfall,
there are no sources of freshwater in the Keys.
Construction began in 1905. Parties of men worked on
different parts of the route earning what was considered a
good wage: $1.25 a day. But conditions were extremely
harsh. >> LUMPKIN: Ten-, 12-hour days.
They worked hard for that $1.25 that they put in every day.
>> STANDIFORD: A lot of men came from cities of the Northeast,
homeless people on the edge, willing to go long distances and
work in unfamiliar and difficult terrain for workmen's wages.
They would get down here and find out how difficult the work
really was-- the heat, the humidity, the isolation, the
mosquitoes, the alligators, the hurricanes-- and they would want
to turn right around and go back up North.
>> NARRATOR: Three hurricanes hit the line while it was being
built. The worst was in 1906 when 125
men were killed. But not even hurricanes could
derail Flagler's efforts to finish the railroad.
Mile by mile, workers built embankments for raised railroad
beds and erected dozens of small bridges to span short gaps
between keys. Yet, the toughest work lay
ahead: building bridges that would cross vast channels of
open water. >> STANDIFORD: Flagler had
become enamored of a new building material called
reinforced concrete, and he'd found the man in all the world
most expert in the use of this material, Joseph Meredith.
It was a lot like asking Wernher von Braun if he'd like to take
part in a rocket building project at the time.
>> NARRATOR: Meredith immediately accepted the
invitation and began engineering the longer bridges.
The first was Long Key Viaduct which still stands next to the
modern highway. It was designed to rest on 180
reinforced concrete arches, crossing more than two miles of
open sea. In 1906, bridge workers started
on the foundation piers. They drove wood pilings into the
ocean floor using steam-powered pile drivers.
Then they sunk tall wooden forms around the pilings that would
hold the water out and provide a dry construction area.
They were called "cofferdams." Next, they poured a special
underwater concrete mix into the cofferdam to form a watertight
seal two to five feet thick around the pilings.
Workers then used a pump to suck water out of the cofferdams and
left the concrete seal to harden.
Later, they could climb inside the dry work area to affix a
second, more refined, wooden form with a lattice-like network
of reinforced steel. This second form would be filled
with more concrete to create a pier.
>> WILKINSON: So you would now have a bunch of stubs of piers
out in the water. The walls, the frames for the
arches, were then brought in and set on top of the cured concrete
piers, bolted together with bolts and lag bolts.
>> NARRATOR: This wooden arch form created the arches of the
bridge and the walls. Workers poured concrete inside.
Once the concrete hardened, the wooden forms were removed.
What was left were walls more than a foot thick on either side
of the bridge and a camel-humped channel running between them.
>> WILKINSON: They filled the inside of those arches with
gravel and rock so that the railroad did not set on
concrete. There'd be too much vibration.
>> NARRATOR: Ties and track were then placed on top.
>> STANDIFORD: If you're out there on a skiff at dawn or at
evening, it looks like a giant Roman aqueduct marching across
the ocean. >> NARRATOR: Long Key Viaduct
was completed in 1908. By then, enough track and
bridges were finished so that passengers could board a train
in Miami and travel 106 miles of the proposed 153-mile route to
Key West. Seven Mile Bridge was the next
major undertaking. It was about 15 miles southwest
of Long Key. Joseph Meredith incorporated two
different styles into the design.
The first would have tall concrete piers with a steel
railroad truss. The second style would be the
same as Long Key Viaduct with concrete arches.
In 1909, workers used the same construction methods they used
at Long Key. They drilled wood pilings into
the ocean bottom and used cofferdams and reinforced
concrete to create the bridge's 546 foundation piers.
>> STANDIFORD: They jumped off land at the south end at
Knight's Key and went out to a little over a mile to a
flyspeck of land called Pigeon Key.
>> NARRATOR: Seven Mile Bridge went directly over Pigeon Key.
Its great piers rested on the island before continuing on over
water. The island was also used as a
labor base camp. Today it's a museum and marine
science camp for students. >> LUMPKIN: All this lovely
vegetation that you see on the island today simply didn't
exist. It was a barren coral rock.
>> NARRATOR: From Pigeon Key the bridge went southward over five
miles of open water. >> STANDIFORD: It was the most
massive, single railroad bridge undertaking in the United States
up to that time and certainly one of the most daunting.
>> NARRATOR: Seven Mile took three years to finish.
The last challenge was the Bahia Honda Bridge.
It was less than ten miles southwest of Seven Mile Bridge
and the distance it would span was a little more than a mile,
but the waters below were 30 to 35 feet deep, at least ten feet
deeper than Long Key or Seven Mile Bridge and the deepest
anywhere along the route. >> STANDIFORD: That bridge had
to be the highest. If the storm is strong enough in
a 35-foot channel, you could have a 35-foot tidal wave, being
swept up. >> NARRATOR: Workers were
challenged to drive pilings deep enough into the coral rock to
create a stable foundation. They then built a steel railroad
trestle on top of the concrete piers.
The bridge was completed in 1912.
>> RONALD ZOLLO: What I marvel at is what the early builders of
the bridge, the older bridges, did, considering the hardships
that they had to suffer in building that.
They didn't have the computational power that we have
now. They didn't have the
understanding of materials, and they didn't have the
capabilities with materials, modern materials, that we can
use in construction. >> NARRATOR: Henry Morrison
Flagler's Overseas Railroad was finally finished on January 21,
1912 after seven years of construction.
Key West was no longer a distant outpost.
>> STANDIFORD: It was an amazing feat.
Imagine, the largest city in Florida and you couldn't get
there, except by boat, now finally reachable by rail.
>> NARRATOR: It's estimated that the total cost of the railroad
was somewhere between $30 and $50 million.
Flagler used his own money to finance it.
Thousands of men worked on the railroad and more than a hundred
died. Flagler himself died in 1913, a
year after the Overseas Railroad was built.
>> STANDIFORD: What he did was stitch the last little piece of
the American continent to the main and truly closed the
American frontier. >> NARRATOR: The Overseas
Railroad would enjoy extensive use until it stood in the path
of one of the deadliest storms in American history.
Journalists in the 1910s called the Overseas Railroad "The
Eighth Wonder of the World." Its bridges were hailed as
engineering marvels. Residents, who once could only
travel between islands by boat, now found an easy way to reach
both ends of the Keys. >> ROBERT DROZ: People in Miami
looked south, and there was another large city not too
far away with good fishing, and they wanted to go there.
>> NARRATOR: The Florida East Coast Railway would make little
money from passenger traffic. The real money was in freight.
But expectations of a flood of imported goods from the Panama
Canal never materialized. Steamship technology had
changed, eliminating the need for coal refueling stops at Key
West. >> STANDIFORD: Steamships had
been refitted with boilers that used a different type of fuel,
and that was oil. So a steamship could take on
enough oil as fuel, passing through the Panama Canal, and
then sail merrily, pretty much anywhere it wanted without
the need for an intermediary stop in Key West.
>> NARRATOR: As a result, the Overseas Railroad never made
much money, but residents found the train invaluable.
>> WILKINSON: It provided a transportation artery to bring
artists, to bring visitors, to bring freight, and so forth,
but it did seem to actually change the culture.
I guess it's like opening the door or something to, uh... to
something new. >> NARRATOR: With the railroad
came a growing network of roads linking it.
Farmers needed to get their produce to the stations, and
innkeepers needed to get tourists to their resorts.
But the biggest spur to road development was the Florida land
boom of the 1920s. Residents on the Keys were more
than willing to join in the real estate frenzy.
>> WILKINSON: The temptation to sell a lot of the swampland
that we had here on Key Largo and the upper Keys and
throughout the Keys was too big a temptation.
>> NARRATOR: To encourage development, Monroe County, the
county representing the Keys, issued bonds for further road
expansion. >> DROZ: They started out with
a... probably a gravel or a crushed shell base, and they'd
grate it and drained it. And in the 1920s, that was a
wonderful road. It didn't get muddy in the rain,
and you could drive on it. >> NARRATOR: By 1928, motorists
could travel on a small network of roads and wooden bridges
running parallel to the railroad and linking parts of the Keys,
but there was still no way to drive directly from the mainland
to Key West. Drivers had to take a 40-mile
ferry trip. >> WILKINSON: Each ferryboat
could take 20 cars, and if there were trucks aboard, it could
even take less total vehicles. >> NARRATOR: The $3.50 fare was
considered expensive for the four-hour trip.
Even worse, the ferries often ran aground.
Monroe County launched a study to determine what it would cost
to get rid of the ferry system and build a complete overseas
highway. But in 1929, within a year of
the study, the stock market crashed, and Monroe County was
broke. The county turned to the US
Congress for help with its highway project, but they
weren't the only ones looking for assistance.
In 1932, 20,000 World War I veterans and their families
marched on Washington to demand early payment of their war
pensions. They were called the
"Bonus Army." The vets were due to receive
$1.25 for every day served overseas, and a dollar for every
day served at home, but not until 1945.
The Depression was on, and they couldn't wait for their
money. >> WILKINSON: And it was a
peaceful petitioning until the government finally intervened.
And they had tanks and tear gas, and it was an ugly scene both
politically as well as socially. And they were successful at
moving them out. They did not solve the problem.
>> NARRATOR: When Franklin D. Roosevelt took office in 1933,
he found a way to help both Monroe County and the Bonus
Army. He offered the vets the chance
to work in a New Deal public works program.
They would earn a dollar a day at various locations throughout
the United States, including the Florida Keys.
By October 1934, more than 700 vets were living in three work
camps in the Keys, building Monroe County's "Overseas
Highway" project. Their fate would be determined
by a natural catastrophe of biblical proportions.
In 1935, just before Labor Day weekend, one of the most
powerful storms ever recorded in the United States was building
force in the Atlantic Ocean. >> WILKINSON: The veterans were
working along very well, and, uh, along in August they get
word of a hurricane brewing out in the Bahamas.
And it was a long way off. >> STANDIFORD: It turned out,
though, that in making a curious bend, it lingered over the warm
waters of the straits and picked up steam.
>> NARRATOR: By Sunday September 2, 1935, the hurricane was
heading straight for the Keys. >> STANDIFORD: You had a number
of residents and highway workers housed in tents on land about
seven to nine feet above sea level directly in the path
of this huge storm coming in. Well, when officials of the work
camp realized how bad it was, they sent out a plea for help to
Miami. >> NARRATOR: The Federal
government authorized a rescue train, but because of a series
of bureaucratic delays and technical mishaps, the train
didn't reach the Keys until evening.
>> WILKINSON: The railroad was now in receivership.
It was bankrupt. So it was not as simple as it
used to be when Flagler had it. You had to go through the legal
manipulations. It took some time to do this.
>> NARRATOR: When the train finally arrived in the middle
Keys where the vets were, the hurricane was in full force.
The train was hammered by hard driving rain, rising water and
cyclonic force winds of 200 miles an hour.
It was a category 5 hurricane, the strongest on
record at the time to hit American shores.
>> WILKINSON: You would not have been able to walk around.
You would have had to have crawled around on all fours to
reduce the wind resistance. The sound is horrible.
>> NARRATOR: The rescue train was stalled halfway down the
Keys at the Islamorada station, after picking up some of the
stranded. Then, just after 8:00 p.m., it
was hit by a 20-foot wall of water, pushed ashore by the
storm's fury. The train's 320,000-pound cab
survived, but its passenger cars were swept off the tracks and
crushed. Miraculously, there were
survivors, but the overall loss of life that night was
extensive. In an area of the Keys where no
more than 1,000 people lived, it's estimated that more
than half were killed. Many were the World War I vets.
>> STANDIFORD: Record-keeping wasn't then what it is today.
Estimates vary wildly, but somewhere between 500 and 800
people were assumed to have been drowned as that storm swept
through the middle Keys that day.
>> NARRATOR: Corpses were found for days in trees, floating in
water, buried inside cars, and under rubble.
>> STANDIFORD: People were impaled by limbs and
decapitated by flying debris. I mean, it was just a real
horror show. >> NARRATOR: Damage was
extensive. >> STANDIFORD: 40 miles
of railroad track swept away, simply obliterated, destroyed.
>> NARRATOR: Three to four miles of railroad embankments were
destroyed, and patches of road were wiped out.
Surprisingly, what did remain standing were Henry Flagler's
railway bridges, but the Florida East Coast Railway was in no
position to rebuild its crippled line.
The state government stepped in, and for $640,000, acquired the
railroad and its right-of-way. The state of Florida now faced a
decision: resurrect the railroad or find a way to build
an overseas highway that would link the roads that survived
north and south of the hurricane's path.
Henry Flagler's railroad bridges survived the hurricane in 1935,
but 40 miles of railroad track were gone, leaving Key West once
again cut off from the mainland. Residents were divided over
whether the state of Florida should rebuild the rail or
construct a new highway. >> DROZ: If they were going to
build the highway, they had perfectly good bridges right
there. They didn't have to go out and
sink new piles or build new footings or do anything.
All they had to do is figure out how to use Mr. Flagler's
existing bridges. >> NARRATOR: The automobile won
out, and legislators went with the most economical solution:
they would build the Overseas Highway using the old train path
and Henry Flagler's bridges. Work to transform the Overseas
Railroad into a highway began in November 1936.
It was concentrated on the middle Keys where the hurricane
had done its worst damage. On land, it was simply a matter
of removing existing railroad track, widening the rail beds,
laying in a crushed rock/gravel foundation and pouring concrete
and paving it. It wasn't much different than
paving over a country dirt road. However, converting the many
railroad bridges to accommodate the automobile traffic presented
an entirely different, more complicated problem.
>> WILKINSON: The easiest thing to do was to widen the top of
the bridge for two-way traffic. So they put cross beams-- steel
girders across the track-- to make a 20-foot wide bridge.
>> LUMPKIN: So, between 1935 and 1938, they went around to each
pier and patched it up as the case may be-- whatever concrete
work needed to be done. They took away the old railroad
equipment, and in its place, they laid down across the
original steel beam, so they could put down pre-stressed
concrete decking. >> NARRATOR: Each bridge was
given two small nine-inch curbs and guardrails.
>> WILKINSON: They actually built in steel rails, and you
can still see some as you drive by the old bridges.
But they're pretty much rusted away now.
But the rails on the bridges were made from actual railroad
tracks taken from the train. >> NARRATOR: Placing a concrete
deck on top of the railroad tracks worked well for all of
the overseas bridges with the exception of one-- the Bahia
Honda Bridge. >> WILKINSON: Most of the arch
top bridges could simply have the top platform widened for a
two-lane highway, but when they got to the Bahia Honda Bridge,
which was a typical steel camelback, steel-suspension type
bridge, it was only wide enough for the train to go through.
>> NARRATOR: With this bridge design, there was no room for
cross beams inside. >> WILKINSON: Matter of fact,
the conductors used to come by, when they go through the Bahia
Honda Bridge and close all the windows, so someone would not be
tempted to stick their hands out in the window and possibly get a
hand knocked off. >> NARRATOR: The trestles could
be dismantled, but road engineers thought of a cheaper
solution. They would build a concrete deck
on top of the trestles. Workers threw steel I-beams
across the top of the bridge, built a platform, and poured and
paved a reinforced concrete road on the platform.
On March 29, 1938, the Overseas Highway opened to traffic.
During its first days of operation, several thousand cars
traveled the distance between Miami and Key West.
World War II brought even more changes to the Florida highway.
Key West was an important Navy base with 4,000 naval personnel,
and better roads were needed to transport troops and equipment.
The federal government upgraded the old roads and auto bridges
from the 1920s. They also shortened the Overseas
Highway route. The most dramatic shortcut was
at Card Sound. Drivers were crossing over from
the mainland to Key Largo using narrow roads and bridges built
in 1928. The Army Corps of Engineers
bypassed this old section by using the path Flagler's
railroad used as it left mainland Florida.
The section linked up with the highway system already
established on the Keys, and cut travel to Key West by 17 miles.
In 1944, the government designated the improved Overseas
Highway "US Route 1." >> WILKINSON: Since federal
money was used, the federal government, you know, named it
as part of the federal highway system.
>> NARRATOR: Motorists could now drive 2,200 miles directly from
Fort Kent, Maine, to Key West. However, the Overseas Highway
was far from finished. More work, more men and more
money would be called on to make the Overseas Highway truly
spectacular. Since its development, the
Overseas Highway stood as one of the most astonishing roadways in
the United States. But by the 1970s, the highway
was showing signs of wear. Modern-day traffic was taking
its toll. >> WILKINSON: Vehicle travel was
also much more prominent. The cars were changing, speeds
were greater. Then we noticed in 1970 that
part of the Bahia Honda overhead portion was beginnin crack
and crumble and falling into the water below.
>> NARRATOR: The Florida Department of Transportation
investigated. >> GUYAMIER: They found out that
it was severely corroded, and also your lane width per vehicle
was somewhat limited. What you were having is a lot of
vehicles going down in the Keys were passing each other very
close. Frequently, you had instances
where mirrors would slap each other on vehicles.
>> NARRATOR: It was time for new bridges.
From 1978 to 1982, the state embarked on a $175-million
program to replace bridges in the Keys with wider, more modern
structures. Bahia Honda was the first major
bridge project. The Department of Transportation
built the highway's only four- lane bridge.
It's a concrete highway on concrete foundation piers.
Seven Mile Bridge, Long Key and others followed.
Long Key Bridge and two smaller bridges used the same segmented
bridge technology as the modern Seven Mile Bridge.
They used precast concrete segments and post-tensioned
steel. Seven Mile in particular became
a model for other bridge projects outside of Florida.
Builders flocked to see it. >> FIGG: Many engineers and
bridge owners came from around the world to visit the bridge
during construction. >> McNEW: It's just miles and
miles of bridge with beautiful scenery on both sides.
You don't see much driving over it.
Riding alongside it or under it, you get to see what it really
is. >> NARRATOR: Seven Mile Bridge,
Bahia Honda, Long Key and 34 other bridges were built or
upgraded along the Overseas Highway.
By 1982, the entire bridge replacement project was
complete. Today, to ensure that these
structures remain strong and safe, each bridge is thoroughly
inspected once every two years. However, for a bridge like Seven
Mile that's exposed to open water, there's steadfast
vigilance for corrosion. Inspection takes about a month
to complete. >> ZOLLO: Seven Mile Bridge is
in a very corrosive atmosphere. It's in a saltwater
environment, essentially. Chlorides in the salt waters are
picked up and deposited on the bridge due to wind action.
Rainfall causes the chloride to drip down into cracks and into
crevices, and eventually they can cause damage to the bridge
structure. >> NARRATOR: But how do you
inspect a bridge that's miles away from shore and more than 60
feet above water? You use a Snooper.
>> GUYAMIER: We pull the Snooper next to the guardrail on the
segmental bridge, and it deploys the arm underneath the bridge,
and it's what allows the inspectors to be able to inspect
the entire segment. >> NARRATOR: The boom on the
Snooper is about 50 feet long and allows workers to go from
one side of the bridge all the way to the other side.
The Snooper is also used to get inside the bridge.
>> GUYAMIER: The only way we have access is through hatches
that are over the waterway, and there's no way you could get
there with a crane. So the Snooper bucket will put
the inspectors underneath the bridge.
They'll open the hatch, then just lift themselves inside the
bridge. >> NARRATOR: Other inspections
are done far underneath the highway bridges by divers in the
water below. >> GUYAMIER: The divers are
going to dive down. They're going to look at each
pier, and they're going to make sure that there's no erosion.
They're going to monitor any kind of erosion.
They going to see if there is any.
>> NARRATOR: If erosion were detected, the Highway Department
would encase the problem area in concrete to prevent further
damage. Today, across these expansive
modern bridges, motorists on the Overseas Highway no longer have
to worry about narrow bridges and torn mirrors.
The biggest headache is traffic. Most of the Overseas Highway is
two lanes. At the moment, there are no
major plans to widen the Overseas Highway.
So, if there is road maintenance or an accident, drivers will
just have to wait. >> GUYAMIER: If we have an
accident on the Seven Mile Bridge, there's not a whole lot
you can do. It's going to back up traffic.
We try to respond to it as rapidly as we can to take the
accident vehicles away from it to let the traffic flow again.
>> NARRATOR: In the case of a severe hurricane warning,
traffic flow could be an even greater problem.
>> GUYAMIER: Monroe County has an emergency management office
that monitors the status of a hurricane and a storm.
If the storm closes in on a particular area, they're going
to determine that it's time to evacuate the Keys or whether or
not it's not going to be necessary.
>> NARRATOR: Evacuation of the Keys is mandatory when
hurricanes starting at Category 3 are predicted... that is,
winds of 110 to 130 mph. In the last 50 years, no
hurricane of that magnitude has hit the Keys.
If an evacuation were called, all lanes would be used for
northbound traffic. However, it could take as long
as 24 hours for cars to get off the Keys to the mainland.
Even then, the builders of this modern roadway are confident
that the Overseas Highway will be able to weather just about
anything Mother Nature can throw at it...
...just as Henry Flagler's old bridges did during the
hurricane in 1935. It is the strength of these old
bridges and Henry Flagler's vision that established a
pathway linking the Keys and provided a foundation for one of
the most extraordinary roadways in the world.<font color="#FFFF00">
Captioning sponsored by</font> <font color="#FFFF00">A&E TELEVISION NETWORKS
Captioned by</font> <font color="#00FFFF">Media Access Group at WGBH
access.wgbh.org</font>
