Tomorrow’s Troglodytes
There are cities beneath the streets.
—Robert E. Sullivan Jr.
The prospect of living underground for long periods was the quirky plot of a 1999 movie comedy called Blast from the Past, about a family that hid out in their bomb shelter in the 1960s, naively mistaking a plane crash on the surface for a nuclear attack.[1]
Another was the nightmarish The Time Machine, by H. G. Wells, where the earth’s people divided themselves into surface people and those staying underground, with horrific consequences.[2] Going underground—literally—has been the topic of much fact and fancy and has gained a lot of traction of late.
In a few short decades the world will face epic challenges that might not be as quirky as dystopian fiction, but the population bomb, rapid urbanization, potential for nuclear conflict, and the demise of our biosphere are just some of the challenges impacting our metro areas. When looking at the cities of the future, we have to look for more than just quick fixes; we need bold new ways based on radical ideas, and planning methods in which to pursue them.
With close to 90 percent of the world’s population projected to live in cities by the end of the century, maybe the only way for future cities to go is . . . down.[3] The idea that roads and support services must be on the ground level of a building is antiquated and ridiculous. A 2013 report by the US National Research Council suggested that “underground facilities may be the most successful way to encourage or support the redirection of urban development into sustainable patterns.”[4]
What goes up can also go down. Some predictions are that two-thirds of the world’s population will be beneath the ground—and alive—by 2050. From subterranean parks and malls to inverted skyscrapers and tunnel-farms, these hidden underground cities and urban projects are going to have us spelunking in some form in the future.[5]
The urban underground is full of deserted shelters and bunkers—remnants of past cold, warm, or hot wars—air raid shelters, bomb silos, subways, storage depots, catacombs, caves, and natural caverns. Most of these single systems and complexes are now empty, but they still exist and they can be utilized, especially in emergencies. Maintenance in their present state costs a lot of money, but there’s a lot of potential to turn a problem into an opportunity. There is plenty of room down there for living spaces, as the deepest mines are much deeper than the tallest buildings are tall.[6]
The success of “building down” might depend on helping people overcome fears associated with small, dark, claustrophobic environments, with being buried alive and not having a clear way out, or with flooding and fires.[7] But there are ways to counter such fears, like connecting all areas of an “earthscraper” to a large, central, seemingly open space that receives light and air from above as if it were a canyon, with clear oases, palm trees, and perhaps illusions of the sky (see below).[8]
Let there be no mistake: living underground is a huge environmental and economic issue. But underground spaces are less susceptible to external influences like natural disasters, and their impact on the internal environment is less than on aboveground facilities.
Dr. Lawrence Palinkas, chair of the Department of Children, Youth and Families and professor in the departments of social policy and health, anthropology, and preventive medicine at the University of Southern California, says a lack of sunlight can cause difficulty with sleep, mood, and hormone function, which can produce chronic diseases of several varieties. But, he says, “timing and routine exposure to bright light that can mimic the properties of sunlight might enable people to live underground for long periods of time.”[9]
Nonviable indoor artificial lighting, like casino lighting, is inappropriate because it causes people to lose their sense of time; and no difference between day and night is evident. When the sun goes down, the brain sends signals to our body to secrete melatonin, which is the sleeping hormone, and when the sun rises, cortisol is released to make us get out of bed.[10] On the brighter side, artificial lighting allows businesses to operate twenty-four hours a day, because workers can come and go at any time without worrying about being confused by sunlight or moonlight.
The “fake nature” of underground ecology in underground plazas featuring bogus palm trees, phony tropical flowers and ferns, and suspicious moss are nothing more than cheap exoticisms that eventually gather dust, decline, and wither, looking rather sad. The scene doesn’t fool anyone, and—what’s worse—it is so artificial that it reinforces the fact that you are underground and away from real nature.
Consequently, sustainable underground cities must have environments designed to look real—or genuine facsimiles—of subterranean life. Daylight will be provided by electrical light sources and in some places by natural skylights; these can focus light and reflect or mirror light to certain areas for growing things and furnishing natural sunlight.[11]
Instead of holding onto the idea that water threatens to flood, causing mold, undermining foundations, and attracting vermin, make water a friend instead. Freshwater may very well become a threat when natural systems are mistakenly tapped.[12]
Clean freshwater, while circulating, can enhance the landscape, creating waterways that become small rivers and creeks. These in turn can be oriented to flow in ponds and pools, aiding plant and animal life and creating a more natural setting and atmosphere. Some of the largest freshwater accumulations are in underground aquifers.
While under-the-earth housing is not common today, it has been around for a long while. Ancient caves were our first natural shelters.
“Greater security, peace of mind, and the ultimate in privacy” were the words used to describe a revolutionary home fifteen feet below the surface that was showcased at the 1964 expo in Flushing, New York. It was devised as a prototype for future residential design where the homeowner could create “his own private world,” shut out the dangers of aboveground living—intruders and storms, for example—and control the home’s environment by dialing in any climate electrically.[13] Jerry Henderson, the founder of Avon Cosmetics, originally funded the model; later, builder brothers Jay and Kenneth Swayze provided funds as well.[14]
The builders had become interested in subterranean living when they were contracted to build a bomb shelter in Plainview, Texas. Afterward, Underground World Homes were featured at the 1964 World’s Fair, and they garnered a lot of interest. However, the brothers came to realize that the cost of building a home underground was prohibitive for the masses and there wasn’t enough market for the proposal. In 1978 entrepreneur Jerry Henderson and his wife, Mary, continued Underground World Homes. The Las Vegas model home measured nearly fifteen thousand square feet, and the house sat twenty-six feet below the surface. The couple also started an underground-building company called Geobuilding Systems Inc., but they shut it down in 1980.[15]
* * *
During the energy crisis of the 1970s, people became increasingly interested in finding ways to reduce their consumption of energy and fuel with energy-efficient forms of architectural design. Others thought to go underground to escape hostile weather conditions. Subterranean living seemed to offer great promise, and experiments were undertaken to explore potentially practical options for homes below ground that would be affordable and energy efficient.[16]
Although the efforts met with mixed success and the underground movement lost momentum, it never completely died out. As we have seen, a lot was learned about what works and what doesn’t when going down to live in the ground. As a result, there are a lot more workable options from which to choose today.
As in many instances, choosing where and how to live offers a myriad of alternatives and answers. One person’s pros may be another’s cons. What this book desires to do is offer reasonable and workable choices—which ultimately are yours.
Less company: people will be less inclined to invade your front yard or sit on your front porch without an invitation.
Protection from natural disasters except earthquakes and flooding.
Doubly effective insulation: underground homes heat up nicely during the day with average sunlight, and hold heat extremely well overnight. And they can be cool in summer. Because the surrounding temperatures are so mild, heating and cooling costs can be reduced from 50 to 70 percent in an earth-sheltered residence. However, this will require the use of a lot of insulation; unprotected walls will eventually reach thermal equilibrium with the surrounding earth unless steps are taken to ensure that the heat produced or collected inside the home is not leached away through the walls.[17]
Minimal cost to heat and almost nothing to cool: starting from an average base temperature of a cool 55°F, underground homes easily reach and hold a warm temperature of 75°. Those that are heated solely with a renewable resource will cost only about $500 a year to heat.
Consistent temperatures, due to the properties of the ground’s thermal mass: the planet’s natural warmth can be exploited as a source of geothermal energy. The ground beneath our feet has a higher thermal mass than just about any other substance. The earth’s capacity to store heat for a long period of time is quite impressive.[18]
Lighting choices: many people are surprised that an underground house can be lit as extensively as conventional houses with lots of natural light.
Blocking of aboveground street noise.
Few chores: cleaning gutters and mowing lawns are not required.
Generally cheaper insurance due to the level of shelter.[19]
Buildings can leak and flood easily causing mold, water damage, and, at the extreme, evacuation.
Limited landscaping: it’s tough to grow plants underground.
Possible cracking and crumbling during earthquakes.
Difficult and expensive repairs: many ordinary materials don’t hold up underground.
Pest problems as bad as or worse than in an aboveground home, as a lot of potential pests burrow or live underground.
High heating and cooling bills during extreme temperatures: these can run as much as 30 percent more than a conventional, well-insulated house of comparable size.
Some differences in depreciation compared to aboveground conventional homes.
Extra lighting needs: some lower floors would need lighting supplied by fiber optics or some other sort of energy source.[20]
Thin sheets of waterproof material specially designed for home protection will need to be applied to the walls and the roof to make an earth-sheltered residence watertight, since the earth can easily pass on moisture to anything with which it comes in contact. A special type of drainage or filtration mat or system will need to be placed over the insulation on the roof to ensure that any moisture that comes from above can be easily channeled away.[21]
Underneath the poured concrete foundation of an earth-sheltered home, a layer of sand at least four inches deep (for the purposes of drainage) should be put in place so that water cannot work its way into the home from below.[22] A living roof made of soil and vegetation can provide even more protection from the elements that will be absorbed by the roots of the green roof’s plant covering before it can seep in deeper and cause trouble.[23] And it can make for an additional garden.
To keep the insulation from touching the earth, a protective layer of waterproof wood, hardy board, or plastic will have to be added, and the layer used must be thick, strong, and well coated with preservatives to withstand moisture and the earth’s pressure without warping or breaking.[24]
The correct choice of location for earth-sheltered structures will go a long way toward eliminating any potential water-related problems. Most importantly, it is essential to always build above the water table; otherwise even the best waterproofing schemes will be tasked to the breaking point, and it may prove all but impossible to keep moisture from leaking into and through buildings.
The weight and pressure of the earth will obviously put an enormous strain on the walls and roof of a below-the-earth edifice, which is why concrete makes an excellent choice for a building material. While 3D concrete printing can work just fine for the foundation and the floor, concrete blocks stacked and coated with a thin layer of fiber-reinforced surface-bonding cement may be the proper selection for its walls.[25] Heavy timbers should be used to construct the roof, which must be able to handle the combined load of the earth and any other built structure above or on it.
Even though underground living can be highly efficient, it is unconventional and has some special requirements. The costs of a home constructed in this style may generally run from 10 to 30 percent higher than the average aboveground structure.[26] Ultimately, the return on investment provided by lower fuel costs will help to negate any extra up-front costs. Studies have shown that over the long haul, earth-sheltered buildings are the most economical for those living in climates that have extreme temperature changes and low humidity. Homes tend to pay for themselves quickly in those locations where relatively long, cold winters and scorching summers are the norm.[27]
One hidden problem that potential underground homeowners must be aware of is the possible presence of radon, a colorless and odorless gas, produced in the ground by uranium decay that can be life-threatening if it collects in sufficient concentrations. When you have a home that is located underground you are much more likely to get deadly seepage in through the walls and floors of your home. Your home can act like a catalyst for the radon to collect and build up over time becoming a deadly component of your indoor air.[28] While it is not impossible to build a safe earth-sheltered structure in areas with elevated radon levels, steps will have to be taken to guarantee that all radon can be collected and vented from the home, which adds another layer of expense onto a project. Inexpensive radon warning meters are available in home-improvement stores.[29]
While some earth-sheltered homes are built completely beneath ground level, many are constructed using a technique known as berming, where piles of soil are pushed up against the walls to form a protective cocoon of earth and vegetation that will separate the outer shell of the home from the elements. Roof covering of soil and vegetation offer more protection against atmospheric heat and cold.[30]
There are three primary design styles for earth-sheltered homes: atrium, penetrational, and elevational. For those who would like to maximize their protection from the sun, wind, heat, and cold, the covered atrium style (a large enclosed central skylight surrounded by a building) is definitely the way to go. In this type of arrangement, each of the rooms of the home will face the atrium from the north, south, east, or west, with spacious windows and possibly glass doors to allow the natural light to filter in from above.
Elevational houses are built by burrowing directly into hillsides or mountainsides and look almost as if they have been inserted into the earth; their side and back walls are completely covered. The front of such a house is left open to the air, usually facing the south in order to harvest the natural heat and light provided daily by the sun. Elevational homes are the least expensive type of structure to construct, and with their hillside locations, they frequently offer grand panoramic views.
Penetrational houses are built aboveground but are designed to fully exploit the protective abilities of the earth. Each wall of such a house is completely bermed with only the spaces over doors and windows left open, to facilitate good cross-ventilation and the effective harvesting of natural light. Variations on the penetrational approach are certainly possible; for example, the southern side could be left open as in an elevational home, while the rest of the house (save for the windows and the back door, of course) would be fully bermed.[31]
There should be plenty of water underground, but drilling for artesian wells must be carefully done as it could cause flooding. Groundwater in aquifers between layers of poorly permeable rock, such as clay or shale, may be confined under pressure. If such a confined aquifer is tapped by a well, water will rise above the top of the aquifer and may even flow from the well onto the land surface. It’s like water in a plastic baggie. When you push a straw through the opening and then squeeze the baggie, water will gush out through the straw.
Lots of things can be grown underground (think “underground” marijuana merchants), especially with current methods of deflecting sunlight or using solar-powered grow lights. Through hydroponics, growing food would not be a problem; aquaponics could yield fish and fowl; and eggs could be easily available. (See chapter 10.)
Solar energy could easily be gathered on the surface to generate and relay power below, or it could be directed through mirrors on the surface to do the same via photovoltaics or via a steam-operated turbine.
Wind farms could also generate energy from above and either direct it for use below or store it under the surface. Geothermal energy would be a no-brainer once a city is established beneath the earth with the capacity to generate power from the earth’s heat. (See chapter 9.)
Actually, the United States has a rather deep and checkered history of being underground. In New York and Chicago, there was a sub-rosa, subterranean society of bootlegging and speakeasies run by the mob and crooked or loose politicians who wanted their dalliances to remain private.[32] Also underground in Chicago was the place that Enrico Fermi and associates first brought about a nuclear reaction, which led to the invention of the first thermonuclear weapon.[33]
Located in one of the least green areas of New York City, this project is aimed at transforming a vacant trolley terminal into an underground park well below street level. The project is currently in the works and is expected to open in 2020. People will stroll at their leisure and appreciate the splendor of underground nature while a periscope-like system channels the sun’s rays downward through the roof. Thanks to this “remote skylight technology,” the park won’t feel like a troglodyte retreat.[34]
In Mexico City designers have created a plan for the “Earthscraper,” a seventy-five-story subterranean city intended to bypass Mexico’s stringent building regulations and the city’s growing space problems. The inverted pyramid will descend nearly 1,000 feet (304 meters) below the surface and potentially house up to one hundred thousand people, with terraced floors receiving natural light from a huge glass ceiling above. The lower floors will need extra lighting furnished by fiber optics.
The enormous complex will house a museum and ten floors of affordable housing. The rest will be made up of commercial office and retail space, at an estimated cost of $800 million. But because the idea is so new, there are no laws or guidelines for building downward in a city area where such activity could jeopardize the surrounding historic buildings.[35]
The largest subterranean complex in the world, the RESO has been in use since the 1960s and is visited by more than five hundred thousand people per day, especially to escape Montreal’s harsh winters. Visitors marvel at its twenty miles of tunnels spread over an area of seven and a half miles of downtown Montreal. It contains hotels, restaurants, galleries, stores, rail stations, cinemas, nightclubs, sixty residential complexes, a library, and a hockey stadium.[36]
The Finnish capital’s “Underground Helsinki” includes more than 125 miles of tunnels as well as plans to continue to expand subterranean public spaces. Thanks to the many buildings’ rough, rock-carved walls, the complex is also a pretty awesome architectural landmark. The city has plans for two hundred more under-the-earth structures.[37]
An eccentric underground project in Kansas City occupies 1,100 acres of abandoned limestone mines. More than 1,600 people work in this naturally climate-controlled, rock-carved space. SubTropolis houses everything from retailers, manufacturing firms, consumer products companies, auto storage, and an array of small businesses. “Six million square feet of it is ready, and we have room to build out another eight million square feet based on demand,” said Dick Ringer, SubTropolis’s general manager.[38]
With a population of nearly 5.5 million people squeezed into a small city-state, the main thrust for going underground is to help solve the land shortage issue while preparing for a growing population. Below the surface of the city is a 3,229,173-square-foot research and development facility that will support biomedical and biochemistry industries, among others, along with restaurants and shopping malls and below-ground residential living areas.[39]
In Coober Pedy, Australia, temperatures can reach 127°F aboveground, but below the surface the temperature is around a mellow 72°. Coober Pedy bills itself as the “opal mining capital of the world,” but the town holds another more peculiar distinction: it may have more cave dwellers per capita than any other place on earth.[40]
Beneath the streets of Saskatchewan lurks an extensive network of tunnels that had been adopted by the Chinese as living quarters and workplaces because they were cheap to run and the weather there was not hostile (unlike the 1920’s Canadian Ku Klux Klan). Rumor has it that Al Capone also used the tunnels for smuggling. Now there are theaters, shops, restaurants, and museums in the space.[41]
Once home to the North American Aerospace Defense Command (NORAD), this underground city was built beneath Colorado’s Cheyenne Mountain to hold thousands of people in the event of a nuclear attack. Terra Vivos, builders of survival communities, is working to create a series of underground complexes made to withstand anything from a 20-megaton nuclear blast or 1,250°F fire to 450-mph winds or a magnitude-10 earthquake. The shelters are outfitted with enough food, water, clothing, fuel, and medicine—and a wine vault—for all inhabitants to survive a year.[42]
Dìxià Chéng, the underground city, covered an area of more than twenty thousand acres and was created as a city-sized refuge from nuclear attack. Approximately three hundred thousand people worked by hand and carried out everything they dug in bamboo baskets. When work began in 1969, the government boasted that the city could contain around six million people. The various tunnel systems linked up around ten thousand atomic bunkers that eventually housed restaurants, theaters, warehouses, factories, a mushroom farm, and sports facilities. Most of Beijing’s underground world was privately owned.
In 2010, Beijing municipal authorities announced that the residential use of underground spaces would be illegal by the end of 2012, citing safety hazards, such as the risk of fire or flooding. In 2015, thousands of residents were evicted from their underground housing.[43]
The city of Kariz-e Kish is more than 2,500 years old and was initially referred to as the system of aqueducts of Kish Island. Today, it is transformed into an amazing underground city, with an area of ten thousand square meters. The underground city has been renovated, and there are plans to turn it into a modern tourist destination with restaurants, residential areas, shopping, and leisure centers throughout.[44]
London seeks to transform its abandoned tube stations into a powerhouse of urban development and address the problem of expansion in one of the most expensive cities in the world. The Old London Underground Company has plans to develop twenty-six sites with an estimated value of £3.6 billion. It hopes to convert them into retail parks, entertainment centers, offices, and cultural venues.[45]
Unfortunately, it seems that the project has been gripped and stalled by legal rows that may take years to adjudicate.
In the early 1900s a Sicilian immigrant, Baldassare Forestiere, began turning what was useless farmland into a vast network of rooms, tunnels, and courtyards as a subterranean escape from the sweltering California Central Valley summer heat. Using only shovels, picks, and other hand tools, he was inspired to excavate for forty years, going as deep as twenty-five feet underground and spanning over ten acres, now known as Forestiere Gardens. He grew fruit trees and grapevines underground with natural light from skylights. Now guests from around the world tour through his grottoes and passageways.[46]
In 2017 Dominique Perrault’s Architecture was selected as the winner of an international competition to design a multimodal hub and shopping center, the Gangnam International Transit Center, to be located in the heart of Seoul, South Korea. Included will be a multimodal hub, train station, urban park, and commercial complex, requiring large-scale underground construction in the city. In the design, there is a green network that weaves all streets and plots together and a continuous tree canopy in a new major landmark park offered to all habitants.[47] The ($1.15 billion) project to build a mammoth underground public transit terminal in Gangnam is planned to open by 2023.[48]
* * *
Living beneath the surface: whether on land, in the sea, or on other planets, it is a slam dunk. It’s an alternative that is happening and will continue to happen in the future. So keep looking down.
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