Modern Marvels: Massive 1912 Oversea Highway – Full Episode (S10, E54) | History

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Modern Marvels: Massive 1912 Oversea Highway – Full Episode (S10, E54) | History

>> 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 Modern Marvels Captioning sponsored by A&E TELEVISION NETWORKS 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 Captioning sponsored by A&E TELEVISION NETWORKS Captioned by Media Access Group at WGBH access.wgbh.org