Underground Infrastructure: Humanity’s Subterranean Footprints

Table of Contents

I. Introduction
II. How Does Underground Infrastructure Take Shape?
III. Infrastructure Origins
IV. Implications of Failed Underground Infrastructure
V. Fears of What Lurks Below
VI. The Future of Underground Infrastructure


From ancient sewers and turn of the century trolley tracks, to fiber optic cable and natural gas lines, there is a lot of underground infrastructure. While we often measure the impact of technology and development by looking at the footprint it leaves on the surface of the planet, there is a vast record of progress and civilization just below the surface.

This article will describe how generations of engineers, city planners, and whole civilizations have layered their legacy through the earth. It will try to capture just how much “stuff” is buried, what all that stuff is, what it is like to work/travel/explore, the hazards it can create as well as the modern comfort and conveniences it enables. It will also leverage current events and high-tech ideas being discussed or tested which will, in part or in whole, involve underground construction and infrastructure.

How Does Underground Infrastructure Take Shape?

Subterranean infrastructure has such a commonplace in everyday life that it is often taken for granted. These structural feats allow for things such as clean water, hygienic sewage systems, household utilities, and efficient transportation. Despite how impressive these systems are, many people do not realize how much effort and expertise is put into executing them.

Constructing any infrastructure involves a multitude of components. The sheer amount of manpower, as well as the abundance of materials and tools, needed for these large-scale projects leads to significant expenditures. In order to prevent throwing money down the drain (pun intended), there are professionals that work together to coordinate these efforts.

City Planners

Contrary to how it may seem in some locations, cities do not spring up by accident. Deciding where certain types of buildings and areas may be placed is called zoning. Zoning and city design is a function that is usually performed by individuals known as city planners.

City planners perform their job by utilizing a city’s zoning code to best designate where specific aspects of a city should be built. By performing this duty, city planners prevent disorganization of a city that would otherwise cause serious issues. For example, industrial locations and waste sites are unlikely to be built next to an elementary school. When it comes time to exact a city planner’s vision, a civil engineer will be consulted.

Civil Engineers

Civil engineers take up the job of creating the functional designs needed to build out infrastructure. However, this career is much more than just drafting outlines. Civil engineers must consider a variety of different resources, ranging from survey reports, maps, and city plans.

They must also take into account and comply with practical restrictions, such as site conditions and the materials that will be used for the project, as well as budget and government regulations. Civil engineering often involves jobs that are huge in nature that pose significant consequences. Because of this, their work must be precise and up to code.

In regards to underground infrastructure, civil engineers choose the correct location on where sewage, utility lines, and other underground constructs should be placed. Once the proper locales have been decided, the project engineer will then begin drafting the project designs.

Impressive Complexity

The complexity of infrastructure that lies below the surface is a feature that plays largely into the effectiveness of metropolitan city planning and civil engineering. Without finely-tuned systems, utility and sewage lines would fall into disarray. As one might expect, these structures are costly both to construct and maintain. According to the American Society of Civil Engineers, the total investment needs for the United States’ water and wastewater improvements will reach $150 billion over the next seven years.

Construction of Underground Infrastructure

Once bids have been accepted and the needed permits have been submitted, contractors will need to procure supplies, materials, and heavy equipment. Earthmoving equipment that may be needed for a project beneath the soil include:

Trenchers are commonly used for quickly digging utility lines like gas and sewage, as well as cable wires for internet and phone access. For larger scale tunneling, excavators may be used to carve out ground materials. Water trucks are often used to soften the soil prior to these processes.

During underground construction, geotechnical engineers are to be consulted to avoid building strategies that could lead to a cave-in or the construction being otherwise compromised. Support systems have to be put in place during the construction in order to keep the crew and other personnel safe.

All plans for underground infrastructure must be built out with extreme accuracy. Therefore, the actual construction may span several months or years. This figure is entirely dependent site size.

Infrastructure Origins

Underground infrastructure has a rich history that spans thousands of years. While today’s systems are quite advanced and designed to fit the needs of modern society, select ancient cultures had systems that were complex and performed their functions sufficiently. However, the advancement of underground infrastructure was far from smooth, with various setbacks that halted its growth until it was finally able to achieve the quality of present-day.

Ancient Waste Management

While plumbing may seem like a modern technological achievement, its history goes back thousands of years. The village of Skara Brae in Scotland of the Neolithic Era housed one of the earliest forms of a toilet, dating between 3100 to 2500 BC. Based upon excavation performed there, it appears this society may have also used a primitive form of plumbing that carried waste away from their settlement to local waterways.

Plumbing wasn’t exclusive to this part of the world either. Mesopotamian cities show pipe and cesspit usage dating back to 4000 BC, while the Harappan people built open sewage channels dating back to 3000 BC. The most well-known ancient sewage systems, however, originated in Rome.

The Roman Empire

In accordance with the massive size of their empire, the Romans undertook the task of creating a water and waste system that is impressive even by today’s standards. Roman engineers developed advanced structures that included water and windmills, sewer systems, dams, and aqueducts that ran both above and below ground.

The aqueducts that the Ancient Romans built were so well-built and structurally sound that some still stand today. A key feature of the aqueducts was a continual slope that forced the flow of water. These artificial waterways performed two functions: bringing water into Roman cities and forcing waste away.

The majority of the Roman aqueduct system ran below the ground. Wells connected the underground portions to the surface to allow the water supply to ventilate. Engineers used lead and terra cotta pipes to outfit these systems. However, the most recognizable feature of the aqueducts was the above-ground archways. Arguably the most famous example of said archways is the aqueduct located in Pont du Gard, France.

The Middle Ages and Renaissance Europe

Following the fall of the Roman Empire, much of the Roman sewage practices fell to the wayside. European cities in the Middle Ages reverted to more primitive practices, such as waste-dumping and cesspits. Conditions were so unclean that it was typical practice in medieval cities to simply throw chamber pot contents onto the street.

Due to these unhygienic conditions, diseases flourished. Cholera, dysentery, and typhoid fever wiped out thousands in European society. Ineffective means of supplying drinking water also increased these numbers. Water that was meant for consumption would have to be boiled.

These failings underscore the importance of today’s water, waste and waste treatment systems. It would take well into the 20th century for effective and safe means to be put into place. Engineers in the 1900s also began to filter and disinfect the water supply, a development that would prevent future generations from being overtaken by diseases of the past.

Sewers Today

Modern sewage systems are centralized in order to allow for efficient and safe treatment of waste and water. Sewage and water lines are constructed below the surface in order to keep them away from the populace. This prevents waste-borne illnesses, as well as water contamination. Primary and secondary treatment are performed to remove sludge, polluting components and harmful bacteria. The leftover byproduct (1.6 billion dry pounds annually in the United States) is then treated in sewage plants.

Implications of Failed Underground Infrastructure

While underground infrastructure provides large benefits, such as keeping hazardous materials away from the population above, failed projects can inflict problems for the governing body that originally commissioned them. From failed train systems to populations illegally live in closed-down underground bunkers, it can be hard for governments to get a handle on these structural mistakes.

Failed Transportation Systems

Constant innovation has a consequence that repeats itself time and time again: as one technology rises, other die out. Transportation is no stranger to this. As automobiles gained popularity, trains and buggies lost much of their presence for everyday travel. The infrastructure built for types of transportation that are no longer used can eventually become a nuisance.

In the case of Washington D.C., the ghost of the district continues to haunt the government and private businesses alike. The nation’s capital once had a streetcar system that ran throughout its metropolitan area. Shut down in 1962, the dilemma of removing the 107 miles of streetcar tracks presented itself. Due to the fact that cars could not safely drive on the track surfaces, they could not be left alone.

Removing the system was difficult and expensive ($8+ million in the day’s money), so the majority of the system did not receive a complete removal. Instead, they were paved over. This solution has caused issues in construction in D.C. today. Crews wishing to install power cables under the capital’s roads face the impediment of working around these lines.

Once transportation infrastructure, both above and below the ground, is no longer used, significant financial and structural consequences have the potential to arise.

The “Rat Tribe” of Beijing

On the other side of the world, individuals wishing to live inside the urban center of Beijing have taken advantage of an unconventional housing opportunity. People who cannot live in properties above the ground (often individuals from the countryside who do not have government approval to live in the city) or choose not to because of skyrocketing rent, have moved into dwellings that exist underground in China’s capital city. They are called the shuzu or “Rat Tribe” by those who live in properties that are above ground.

While some of this housing has sprung up in basements of Beijing apartment buildings, a great deal of the underground infrastructure used as housing by the shuzu is converted air-raid bunkers that was built under the communist regime of China during the Cold War. Conditions of the housing in these shelters is often cramped and dank, with limited ventilation and access to bathrooms. Despite these conditions, these individuals choose to live here to be close to the city center. Affordable housing is often on the outskirts of the city, making commutes difficult.

As Beijing’s government seeks to make their city more modern, they have condemned living in such settlements. Safety precautions, such as fires and flooding, Mandatory evacuations have been enacted, displacing thousands.

However, the government is facing an uphill battle when it comes to completely removing all underground communities. It is estimated that anywhere from 200,000 to 1 million Beijing inhabitants live below the surface. As the city’s population continues to grow and available housing continues to dwindle, it is likely that many more will be forced below the surface.

Fears of What Lurks Below

Fear of tight spaces and the dark are commonly held phobias. Therefore, it is only natural that there is speculation of what might be hiding in the shadows of what civilizations construct below the ground.

Association with the Dead

It is common across cultures for the dead to be placed below the ground. From crypts to cemeteries, the deceased are buried here in order to let them rest in peace as well as to keep remains safely away from the living. With human superstitions about death in mind, it is natural that society may fear such places.

One of the most visually frightening examples of this is catacombs. These underground constructs that span great distances under Europe’s oldest cities host remains numbering in the millions. Many of the deceased were taken by the Black Plague that swept the region.

The most famous catacombs are undoubtedly those located in Paris. The catacombs in the French city cover approximately 200 miles of caves and tunnels. It is not an unusual sight while touring these structures to see immense piles of human bones. The estimated total of the dead that reside underneath Paris in its catacombs is between 6 and 7 million. With real-life examples such as this, it is no wonder we as humans fear places below the earth’s surface.

Stephen King’s “It”

There are also fictional representations in modern-day culture that have led many to fear what might reside in underground structures. In 2017’s remake of Stephen King’s “It”, a cannibalistic clown abducts and murders children with abandon. One of the key characteristics of the clown, named “Pennywise,” is that he dwells in the large sewer complex of the city of Derry. The taken children are dragged screaming down the depths of the sewer lines, never to be seen again. It is no wonder that many moviegoers were wary of storm drains for months following the film’s release.

The Future of Underground Infrastructure

While the history of underground infrastructure is long, it is not stagnant. Many Entrepreneurs, such as Elon Musk, have impressive visions of what we should be using the space below our cities to build.

Elon Musk’s Hyperloop

Elon Musk, the billionaire founder of innovative corporations such as SpaceX and Tesla, has been actively seeking a way to construct a transportation system known as the “Hyperloop.” The system would use a semi-vacuum-tube electromagnetic transportation system. By utilizing this technology, high speed highways could be created. For example, the commute time from Washington D.C to New York would be about 30 minutes.

However, as the Hyperloop would need to be built in almost a straight line, the only viable option is to build the system underground. While this technology is still years away, Musk has founded the Boring Company to set about the immense job of digging the tunnels that will be needed by the Hyperloop.


While we as humans may be wary of what lies below the ground, underground infrastructure is definitely here to say. As we look to future technologies, such as the Hyperloop, and an ever-growing population, it seems that the only way to build will be down.

Related Posts

  How to Professionally Pressure Wash Your Deck Clean

  Types of Heavy Equipment Lease Financing

  Top Three Reasons to Rent vs. Buy Heavy Equipment

  How to Become An Early Riser: 25 Science-Backed Tips

  17 Science-Backed Benefits of Working Outdoors

  How to Stay Healthy When You're Standing All Day

  Change Orders for Construction Explained

  How To Track an Employee's Time and Attendance

  How to Remodel a Store to Boost Sales

  12 Warehouse Layout Tips for Optimization