The Ground Beneath Our Feet 

By Luke Carothers

It wasn’t until recently that humans gained a tenable grasp on traversing the skies.  For far longer, the great builders of society were much more interested in what lay beneath the ground.  History is filled with examples of different peoples using the tools and techniques available to gain access to the ground.  The reasons were not uniform; some sought shelter from weather and enemies in excavated caves; other groups knew underground storage would make their food last longer.  Not least among the reasons for our obsession with the underground, however, is the bounty in materials it holds.

The extraction of underground material is almost synonymous with the development of human culture and technology.  The oldest example of mining activity by humans–the Ngwenya Mines in Swaziland–are at least 42,000 years old.  During the Middle Stone Age, the people in the area began extracting red haematite and specularite from the ground, which was then used to create red paint.  Although rudimentary in its composition, this early form of paint still exists in many places–dotting cave walls throughout Swaziland even in the modern age.

Similar examples exist all over the world–of minerals being extracted and used for paint–and are a testament to the development of human communication and expression over history.  By using tools to excavate minerals in underground spaces, humans became capable of new forms of lasting expression.  Paintings on rock walls contained key information for early humans–communicating the presence of food, water, shelter, and danger. This access to paint allowed humans to express their thoughts and feelings in a new and lasting way.

It’s also no surprise that many of these early humans chose the walls of caves as their canvas.  As humans were learning to construct external shelters capable of withstanding the elements, caves served an important purpose for many migratory groups.  As our tools and materials became more advanced, humans began to cluster into groups based around constructed buildings.  Many of these early settlements formed around resources that could be extracted from underground.  Access to these resources shaped the way cities were built and added to their wealth and influence.  

Advances in technology have changed what resources and their methods of extraction, but this pattern for shaping the built environment still exists for cities built in the modern era.  For example Kansas City, Missouri was founded on the site of a trading port on the Missouri River in 1850.  Following the American Civil War, the once-rural trading port began to grow rapidly as a result of the Hannibal & St. Joseph Railroad bridge being constructed.  To accommodate the resulting population boom, massive amounts of concrete needed to be sourced.  The answer lay beneath the Missouri soil as the area’s hills were laden with the ideal limestone for cement production.  During the latter half of the 19th century through the early 1900s, engineers and miners carved out millions of square feet of limestone in and around the Kansas City metropolitan area.

In a period where technological capacities directly align with material need, Kansas City became a very large metropolitan city in a relatively short period of time.  This time of growth coincided with the City Beautiful movement, of which Kansas City became a leading example.  Neighborhoods, parks, and buildings were constructed under the belief that their beauty would intrinsically improve the lives of the population.  Fueled by the limestone being quarried and the ideals of the City Beautiful movement, iconic buildings such as Union Station and neighborhoods like Southmoreland elevated Kansas City from a small “cowtown” to a large, cosmopolitan city.

There are countless examples mirroring Kansas City both in America and throughout the length of history.  Indeed, access to underground material and the understanding of its properties is also at the heart of the modern AEC industry.  Starting during the industrial revolution, the need arose for specialized professionals who could develop tools and machinery to extract and process resources.  Shortly after, further specializations were needed for things like moving materials over long distances.  Many of the modern engineering disciplines can find their roots in either the extraction and processing or logistical movement of these key resources.

As the AEC industry navigates the challenges of the next decade and beyond, our historical relationship with the ground and resources beneath can provide important context that can help in these struggles.  Humans have an inextricable link to these resources, and we have relied upon them to develop socially and physically.  When viewed in comparison to our historical relationship, our modern understanding is still in its infancy.  As we continue to grow our understanding of the underground, it is important to recognize and respect this need to continue learning because, as history would suggest, many solutions to these problems can be found underground. 

Luke Carothers is the Editor for Civil + Structural Engineer Media. If you want us to cover your project or want to feature your own article, he can be reached at lcarothers@zweiggroup.com.