The Simple Genius of the Interstate Highway System | Wendover Productions

0:00This video was made possible by CuriosityStream. Subscribe to their Nebula bundle deal at curiositystream.com slash Wendover to watch an exclusive companion video to this. It's really just four lanes, a median, and some on and off ramps. The interstate highway system is no engineering marvel, no unprecedented undertaking, no massively innovative concept. It's a simple idea, one that arose since the earliest days of the automobile. It's not exciting, which is why it often goes so under-appreciated. Take the interstates away, though, and you have a weaker nation. You have one with dramatically starker regional divides, one with increased decentralization. More specifically, you have a nation absent of a noticeable portion of the lace-1900's economic development in transformation. These words, like the system itself, still aren't exciting, but put more simply, if you are an American, regardless of whether you use the interstate system,

1:03your life would be noticeably different in a reality without the interstates. It's a single collection of roadways, with an influence so great that it permeates into every American's life. It all started here, one hundred and two years ago. 79 vehicles departed from the White House's ellipse at 11.15am on July 7, 1919. They snaked through the district streets before crossing into Maryland and stopping for lunch in Rockville at 12.30pm. The coupling on one of their kitchen trailers broke and a car's fan bells too, but all in all, it was an uneventful seven-hour 46-mile, 74-kilometer journey to the Frederick Fairgrounds. 12.5 hours later, they woke up, left, drove, arrived, and slept again. This cycle repeated itself. Day after day, they cut 40 or 50 or 60 miles deeper into their westward journey. The convoy climbed through the heights of the Appalachian Mountains,

2:04trekked through the mud of Ohio before crossing the Mississippi River at 4.10pm on July 22. From there, they entered an area defined by desolation. Few dared venture west in a motor vehicle in 1919, always opting for the relative comfort and speed of passenger trains. This convoy, though, was making the journey specifically to determine just how difficult this feat was, to what extent such a journey was feasible for military logistics purposes. The answer came quickly. Despite routing themselves on the most developed transcontinental road of the time, the Lincoln Highway, they constantly had to divert around disrepair, physically disassemble covered bridges to get their trucks through, and fight physics on roads too narrow for an oncoming car to pass. Gas stations were few and far between, so such travel required truly expedition-level planning. Each time they entered a city, though, they were greeted by hordes of intrigued locals and dignitaries,

3:06but those crowds thinned as the convoy crawled further into the desolate west. Most, but certainly not all of their vehicles successfully traversed the Rockies, and the same can be said for their trip across some of the Lincoln Highway's roughest roads in Utah. With time, though, the train reversed, roads improved, and they finally saw pavement again as the convoy entered California, its final state. After a final evening in Oakland, California, the vehicles loaded onto a ferry across the bay and made a ceremonious arrival in San Francisco, accompanied by a massive parade and a formal dinner. That was September 6, 1919, 62 days after their departure from the White House ellipse. Having concentrated nearly all their waking hours on driving, the math works out to an average travel speed of just 5.65 miles or 9 kilometers per hour, a staggeringly slow pace on a road branded as a highway in a year featuring technologies such as electric refrigerators, airplanes, and long distance phone service.

4:11The convoy accomplished its mission of appraising the feasibility of this route for more practical military purposes, but the report back to Washington was not positive. One lieutenant colonel tasked with observing the journey, wrote, quote, extended trips by trucks through the middle western part of the United States are impractical until the roads are improved, and then only a life truck should be used on long hauls. It was clear that, for now, until roads were improved, transcontinental motor trips would remain the domain of publicity stunts and enthusiasts. But then the years started passing. Administration after administration, observing the growing presence of motor vehicles in the lives of increasingly everyday Americans, recognized that road construction was not something that could be left the responsibility of states. While individual states did make plenty of progress building high quality urban and rural roads, their interests were insular. Iowa, for example, would have no interest building a highway with the primary purpose of connecting Illinois to Nebraska.

5:16As Americans went off to fight in Europe during World War II, they observed the efficiency of Germany's national rikes out of the highway system, but when they returned home, they were forced to navigate a patchwork of state systems of varying quality to get anywhere beyond their local areas. In the 1950s, when America was a near decade out from landing men on the moon, it still took significant planning in the better part of ten days to reasonably traverse from one coast to the other. While this might have been inconvenient for road tripping Americans, it mostly meant that there were regions that simply could not compete with coastal areas in the industrial sector due to high transport costs and times. It was clear something had to change, but efforts to increase highway construction at the federal level were constantly stalled by funding issues and a general lack of a listen. But then came someone new. One of the members of the 1919 Transcontinental Convoy, in fact the very Lieutenant Colonel who provided the earlier report on the journey to Washington continued on in his military career and rose to the ranks until he became Supreme Allied Commander of the European Theatre in World War II.

6:27Then, upon return to the US, he entered a political career, culminating with his inauguration as president on January 20, 1953. This was, of course, Dwight D. Eisenhower. With the groundwork laid by decades of planning and false starts, Eisenhower's task was centered on finally finding the political will and funding to turn this concept map, a 1955 publication by the Bureau of Public Roads into reality. After nearly three years of political maneuvering, he succeeded. On June 29, the Federal Aid Highway Act of 1956 was signed, dedicating some $25 billion to constructing 41,000 miles or 66,000 kilometers of highway. Unlike previous attempts at similar programs, the federal government would now pay 90% of the costs of these interstate highways with individual states responsible for the rest. Largely funded by a hike in the federal gas tax.

7:29Just three months after the bill signing, Paving Work began on a section of interstate 70 in Kansas, and two months after that, the same section opened to the public, representing the first miles of a system that wouldn't golf the country over the coming decades. Now, whether it's I-40 in Tennessee or I-90 through Idaho, the way these roads were built was highly, highly standardized. That was, after all, the point. These standards are codified in a simple eight-page document entitled a policy on design standards interstate system. To start with, fundamentally, interstates must have controlled access, meaning the manner in which vehicles enter or exit the roadway must be controlled through on and off ramps. That's why, unlike with many state highways, you never see intersections with stoplights on interstates, except when rules are violated. The standards also set out a minimum speed. 50 miles or 80 kilometers per hour in urban and mountainous areas, 70 miles or 110 kilometers per hour in rural areas, and maximum grade.

8:37Up to 7%, corresponding to 370 feet of elevation gain per mile of road, or 70 meters per kilometer, depending on speed and topography. There must be at least two lanes in each direction of travel, 12 feet or 3.5 meters in width, with a cross-loop, essentially an angle to allow for rain runoff, of at least 1.5 and ideally 2% grade. Tunnels and bridges must have at least 16 feet or 5 meters of vertical clearance, although less is allowed through urban areas as long as an alternate route with 16 foot clearance is available. Aside from a few smaller details, that's the entirety of the interstate highway design standards. It's incredibly simple. Implementing this nationwide, however, was no simple endeavor. With the project started in the 50s, one mile of interstate cost some 8.5 million dollars to construct, or 5.3 million dollars per kilometer. However, through the decades, as labor cost arose and the simplest sections stood completed, this ramped up to over 34 million dollars per mile, or 21 million dollars per kilometer.

9:44Unsurprisingly, the interstate system quickly blew past its original 25 billion dollar budget allocation, but people and governments were convinced. The project gained more and more funding, and was reaching completion by the time the 80s turned into the 90s. To complete the original vision, just one last section remains, a 12.5 mile 20 kilometer stretch through Glenwood Canyon, Colorado. With thousand foot walls flanking on each side, little room exists aside the Colorado River for a roadway, but a complex collection of bridges and tunnels were constructed at a cost of 960 million dollars, inflation adjusted, corresponding to 75 million per mile, or 47 million dollars per kilometer of roadway. Once this engineering marvel was completed in 1992, however, the nation was connected, and more than two decades after his death, Eisenhower's vision was realized. His 62-day transcontinental expedition from 1919 now takes a mere 42 hours.

10:49In such a decentralized country, consisting of a patchwork of states, each with unique governments, laws, cultures, and more, the consistency of a nationwide federal transportation system is, in and of itself, unique. It is one of the most regular interactions Americans, especially in Farflung, Western, and Southern regions, might have with a federal program. Today, the largest urban center located further than 25 miles or 40 kilometers from an interstate highway is Fresno, California, with a population of about half a million. In fact, only 14 cities with over 100,000 people are located further than this distance. Even Alaska, Hawaii, and Puerto Rico are now included in this program, despite the fact that their interstates don't actually extend interstate. With wide lanes, smooth turns, consistent grades, and more, these highways are remarkably safe. While nationwide, the U.S. averages 1.3 deaths per 100 million vehicle miles traveled, interstates, for the same 100 million vehicle miles, observed just 0.55 deaths each year.

11:59Incredibly, that means that, assuming the alternative is equivalent to travel on non-interstate roads, this system is responsible for saving about 6,500 lives per year. Beyond the moral components, the innate human desire to preserve life, the U.S. Department of Transportation, on a statistical basis, values a human life at $11.7 million when evaluating potential safety standards, so the safety profile of the interstate highway system by itself has a theoretical economic impact of about $75 billion per year, therefore easily justifying its cost alone. But then there's the more direct impacts. Among the more populated states, construction disproportionately took place in southern states, such as Georgia, South Carolina, or Arkansas, on a basis of miles constructed per capita. Then, in less populous states, the interstate disproportionately penetrated the American West, with states such as Utah, Montana, Nevada, and Wyoming receiving the most miles per capita.

13:00Therefore, it was the South and West that received the greatest impact. In essence, what these roadways did was connect the U.S. economic centers to the periphery to the periphery had the most to gain by, effectively, reducing the relative distance to centers by a factor of 30% on average. In the case of interstate 5, for example, which runs along the entire West Coast from the border to Mexico to that with Canada, California, the state that encompasses the majority of its distance, actually sees the smallest benefit. That's not to say the benefits is small. The removal of the interstate would correspond to a 6% loss in overall income in the state, but Oregon, the 12th most sparsely populated state in the nation, would lose 15% of its income if I-5 simply disappeared. It's worth fully considering just how staggering that statistic is. A single, simple, four-lane roadway, stretching some 300 miles or 500 kilometers through Oregon, attributable for 15% of its income.

14:08This does, however, make sense. Oregon's economy, significantly undergirded by the natural resources, manufacturing, and agricultural sectors, is highly trade dependent. The state does not, however, have any major export ports, so when a manufacturer in Salem, Oregon, for example, needs to transport the finished products to the port of Oakland, it would likely hire a truck to take the 9-hour journey south on I-5. The shortest non-interstate route, however, would take 13.5 hours on roads with potentially burdensome weight restrictions, inadequate facilities, low bridges, and other constraints. It just makes getting product out harder. Now, ultimately, transport cost is rarely an enormous portion of a given products cost. A 5-cent increase on a $10 product produced further from Oakland isn't massive, but that's not the context that matters in the competition, between places, for industry. If the options are between a state that has a conduit enabling lower cost, reliable, fast transportation in and out, and all other factors are the same, why would a manufacturer decide to locate in the more poorly connected place?

15:19The economy is a competition, and in competition, the smallest margins matter even when they don't in a non-competitive context. Considering the alternative was the status quo, individual states building their own highways, disconnected from any national program, this program caught the states that couldn't afford massive infrastructure projects, many of which were in the south and west, up to the rest. Therefore, interstates made these states more competitive, but reducing their relative distance to the rest of the world. That's not to say the program was perfect, though. Just as much as it proved revolutionary to more rural areas, it gutted cities. Neighborhoods, predominantly poorer ones, were leveled to the ground to make space for interstates and their associated infrastructure. This often created clear physical barriers between certain neighborhoods and urban centers, which reduced opportunity in these excluded neighborhoods. We also had the effect of encouraging reduced density, which increases the environmental impact of cities, create scenarios where job opportunity is linked to car ownership, and additional potential negative impacts.

16:30Altogether, the way in which interstates interact with cities was often poorly planned and executed. But when examined in aggregate, the interstate highway system is one of the best investments the United States ever made. While by no means unique to the United States in concept, the vastness and regional disparities in the country meant such a system had a uniquely powerful impact. For every dollar spent on the program, it has returned at least six in economic benefits. In the context of nations, connectivity is power. For the reason why the interstate highway system is the most impactful infrastructure program in American history is simply because, as of now, it's the largest. I definitely enjoy nerding out about the interstates, and hopefully you now do too, so I made a whole other video about the strangest quirky sections of the system, like why interstate 180 exists, just connecting to a town of 700 and traveled on by only about 100 vehicles per hour,

17:36and I wanted to tell you that essentially exists because one of the only stoplights on an interstate. You can watch that video on Nebula, the streaming site founded by myself in loads of your favorite educational creators. There's no algorithm, meaning we can upload without worrying about how clickbaitia video is, and no ads or sponsorships, meaning you can just enjoy the videos themselves. Plus, we regularly release exclusive companion videos, extended cuts, big budget originals, and more. What makes Nebula even better is the best way to get access to it, the CuriosityStream bundle deal. You sign up through them, and then you also get access to CuriosityStream, home to an enormous catalog of top-quality nonfiction shows and documentaries, like Highway to the Arctic, about Canada's annual endeavor to build ice roads through its frozen north to provide a seasonal road connection for many of its most isolated villages. Nebula and CuriosityStream are both fantastic streaming sites that I find myself regularly using, and they come an incredible price. Just 1479 a year with the current sale at curiositystream.com slash Wendover or by clicking this button.

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