Designing Cities for Healthier Microbiomes

Artistic rendering of the human microbiome / The Why Files

Humans are essentially super-organisms or holobionts made up of both human cells and those of micro-organisms, such as viruses, bacteria, archea, protists, and fungi. Researchers now know the human body hosts a comprehensive ecosystem, largely established by age three, in which non-human cells vastly outnumber human cells. The latest study from the American Academy of Microbiology estimates each human ecosystem contains around 100 trillion cells of micro-organisms and just 37 trillion human cells.

But while rainforest or prairie ecosystems are now well-understood, the human ecosystem is less so. As researchers make new discoveries, there is a growing group of scientists who argue our microbiomes are deeply connected with our physical and mental health. The increased number of prebiotics and probiotics supplements on the shelf in drug stores and supermarkets, and availability of fresh pickles and kimchi in local farmers markets, are perhaps testaments to this increasingly-widespread belief.

The question at the Environmental Design Research Association (EDRA) conference in Oklahoma City was: Can we design cities to better support our microbiomes and in turn our overall health?

Richard Wener, an environmental psychologist at NYU, explained how our built environment is filled with micro-organisms. “The walls of our kitchen and bathrooms are covered in bacteria; most of them aren’t pathogenic.” The micro-organisms found in our environments are constantly interacting with our microbiomes, so we are “perpetually assembling and re-assembling different species.”

For Wener, this begs the question: “What is an individual?” If we are constantly evolving with the micro-organisms in our environment and therefore changing our composition, “what individual are we talking about?”

While our microbiomes may evolve, they still have a distinct signature. Researchers can now identify people by their unique microbiotic markers — crime-scene microbes are now analyzed in forensic studies to identify who was at a location.

Places have unique microbiotic signatures as well. Through their PathoMap project, Weil Cornell Medical College organized citizen scientists to examine the bacteria in subway stations and found stations had “consistent signatures.” The microbes in stations near hospitals were different from neighborhood signatures. “The microbes really depend on who lives there.” (See data visualizations of the findings).

So can we design the city in terms of microbial species? Can we design buildings and parks to create “selective pressure that supports biotic life that is good for humans?”

Turns out good microbes can be put to better use while bad ones can be suppressed.

In Brooklyn’s Gowanus Canal, a highly-polluted Super Fund site, researchers took samples of sludge at the bottom of the canal and found bacteria had been digesting some of the worst industrial waste for decades. “They co-evolved to eat solvents and toxins.” At a slow pace, Wener thinks these bacteria could actually clean-up the entire canal. Through interventions, “we could encourage the growth of this bacteria.”

Buildings could be designed to kill off pathogenic bacteria and support the healthy microbes in our biomes. Wener said a recent Brazilian study found pathogenic bacteria, which comes from people, thrive in closed spaces. In open air environments in the Brazilian rainforest, where domesticated and wild animals roamed through indigenous villages, there were no pathogenic bacteria, but in closed building interiors found in Brazilian cities, researchers found many. The conclusion: If you increase exposure to light and air flow in buildings, you will reduce dangerous bacteria.

Through urban farming and gardening — or just plain playing in the dirt — humans can also increase their exposure to healthy microbes found in soils. A group of scientists and advocates argue that greater exposure could help fight depression and anxiety and reduce rates of asthma and allergies in both kids and adults.

The incredible increase of allergies among Western populations may be caused by our “sterile, germ-free environments” that cause our immune systems to over-react to everything from nuts to mold and pollen. Dr. Brett Finlay and Marie-Claire Arrieta even wrote a book exploring this: Let Them Eat Dirt: Saving Your Child from an Over-sanitized World.

Wener said we have created cities that reflect our fear of bacteria; instead we must create microbial-inclusive cities that improve our health. “Most microbes in our bodies have co-evolved with us. They are important to our vital functions. The future of urban planning and design should support healthy microbes.”

As part of this vision, landscape architects could design parks and plazas to be filled with accessible garden plots and healthy soil-based play areas that let both adults and kids get dirty. We could design for holobionts instead of just people, boosting the health of the collective urban microbiome in the process.

Wener’s colleage at NYU — Elizabeth Henaff — is leading much of this research. Learn about her artful experiments. Read this article from Michael Pollan in The New York Times outlining the connections between our microbiome and health, and this Q&A from The Guardian.

Remnants of Oglethorpe’s Utopian Vision Survive in Savannah’s Squares

James Oglethorpe statue in Chippewa Square / Jared Green
James Oglethorpe statue in Chippewa Square / Jared Green

James Oglethorpe, founder and planner of Savannah, Georgia, was educated during the height of the Enlightenment. Influenced by John Locke and Isaac Newton, he was a visionary who sought to use “scientific laws to establish the ideal city,” explained Steve Smith, with the Massie Heritage Center, during a tour at the Congress for New Urbanism.

Upon the approval of his petition to create the colony of Georgia, named after King George II, Oglethorpe set sail for the American south with 100 settlers, with the goal of establishing an “anti-urban settlement, a low-density, agrarian community,” said David Gobel, an architectural history professor at the Savannah College of Art and Design (SCAD).

Oglelthorpe thought cities were the root of all social ills. Removing people from a productive relationship with the land and a healthy connection with nature resulted in bad morals, crime, and debt. He sought to create a new colony for people who had suffered in urban debtors’ prisons, but ended up attracting many merchants, artisans, and others to his venture.

In his new colony of Savannah, established in 1733, Oglethorpe organized the community along an unusual layout — now known as the Oglethorpe Plan — characterized by wards made up of 40 60-feet-by-90-feet lots on either side of a central square, framed by “tithe lots” where churches and civic centers were found. At no time in history has there been an urban plan like this.

Original Oglethorpe plan / Connect Savannah

In this village format, each colonial family would get a lot, which included a garden and a 50-acre farm outside the town center. Ogelthorpe originally envisioned four wards, with a maximum of 240 families.

According to Gobel, the utopian plan of Ogelthorpe was a failure. “He took people from the urban core of London and told them they will become farmers — in clay soil in the southern heat.” Oglethorpe was also very restrictive — alcohol wasn’t permitted; families were restricted to the property they were allocated; lawyers and Catholics weren’t allowed; and due to his moral opposition to slavery, that evil practice was banned.

As we heard from Vaughnette Goode-Walker, a local historian who gave a tour of the African American history of Savannah, Oglethorpe eventually succumbed to the slave culture established in nearby South Carolina. “The first settlers were lazy, drinking, and didn’t do anything. Oglethorpe had to borrow slaves until 1741” to clear the land and construct the city. By the time Oglethorpe returned to Georgia in 1752, his utopian vision was in ruins; he had been “overwhelmed.” And the reality was that “slaves built the city.”

By 1750, “slavery arrived with a vengeance.” Between 1761 and 1771, some 10,000 slaves were sold in the markets near the wharfs, where boats loaded with suffering human cargo would arrive from the Caribbean and Africa. The first slaves worked rice plantations and then later cotton fields. By 1810, some 44 percent of the workforce was enslaved. In 1860, the population of the city was 22,000, with some 17,000 enslaved people and 700 free blacks, many of whom owned slaves themselves.

The anti-materialistic, equitable vision Oglethorpe had for the city wasn’t realized; and the physical form of his idealism was corrupted as well. Oglethorpe envisioned a maximum of four wards, but beginning in the 1790s, the ward system was replicated and eventually expanded to 24 wards (there are now just 22). “Savannah became a city filled with squares; it’s almost ridiculous,” Gobel said. But these squares are now what helps draw millions of tourists to Savannah every year.

Historians in Savannah have long wondered: why squares? The Massie Center is a believer in the “Turin theory,” posited by Cornell University professor John Reps, which contends that Oglethorpe modeled the squares after the Piazza Carlina in Turin, Italy. But Gobel believes Oglethorpe instead modeled them after squares created in London in the 17th century. “London was square-crazy then. There were more than 20 in the West End, where the trustees of the colony had homes.”

Piazza Carlina in Turin, Italy / @rtisan Traveler, Pinterest
St. James Square, London / Eric Parry Architects

Still, the Savannah squares aren’t like their possible Italian or English inspirations. “The Savannah square is nothing like an Italian piazza, because there are lots of openings. There is a porosity to the squares, with all the streets that come off them, which breaks down the sense of an enclosed space. And unlike the squares of London, the Savannah squares are open, with no fences.” (Gramercy Square in New York City is more like an old English square, with its private key for residents who live beside it).

Porosity of the squares of Savannah / Jared Green
Fountain in square / Jared Green

The squares were originally completely utilitarian. “They were used as pasture, marketplaces, for exercise or as military encampments. They started as left-over, residual spaces.” The primary feature of many was simply a well. According to Goode-Walker, African Americans certainly weren’t allowed in the squares — “slaves stayed in the lanes behind houses.” And back then, the lanes and streets were filled with mud and horse excrement, which is why most whites lived in the upper levels of the homes they built.

But slowly the squares evolved into important spaces of public beauty. By 1810, there were mentions of “how lovely the squares were,” said Gobel. Curbs separated them from the streets; trees were planted; and north-south and east-west pathways were established. In between this matrix of paths, the city erected giant monuments to heroes of the American Revolutionary War.

Sgt. William Jasper Monument in Madison Square / Jared Green
Sgt. William Jasper Monument in Madison Square / Jared Green

There have been “many changes to the squares over the years. They have been gussied up; today, they are more like garden parks.” Landscape architect Clermont Lee renovated and restored five squares from the 1950s to the 1970s. In 2010, EDAW (now AECOM) restored Ellis Square to the original plan, after the old City Market built over it was torn down. Today, a team of landscape architects — who work for the city government in a group distinct from the parks department — maintain the squares.

In their beautification, the squares have transitioned from places of recreation, commerce, and civic action into places to relax and commune with nature and the community. “The goal today is to prevent any active use. Monkey grass was put in to keep out kids,” Gobel fretted.

Not play-friendly Savannah Square / Jared Green

The squares wouldn’t be the draw they are without the amazing Live Oaks that were planted more than 150 years ago. The original trees of the squares — the Pride of India or “China berry” tree, a relative of the Mahogany — were all killed off in a hurricane in the 1850s. A towering canopy of Live Oaks, Palmettos, Magnolias now oversee the squares, which feel heavy with history, but where, today, all ethnicities can be seen together.

Live Oak in a Savannah Square / Jared Green
Magnolias and Live Oaks in a Savannah Square / Jared Green

According to Gobel, there is a history that still needs to be more deeply explored: “a landscape history of the city has never been done.” A story needs to be told about the horror of the landscape of East Upper Factors Walk, which was created by Irish sailors with ballast from ships, where slaves who had just been purchased were kept, a haunted place Goode-Walker said she doesn’t bring tours.

East Upper Factors Walk / Jared Green
East Upper Factors Walk / Jared Green

And the story of the amazingly resilient natural and cultural communities that define the character of the city — the diverse trees that shade the city, and people who built Savannah and shaped its evolution.

To Create a Sense of Belonging, Embrace Cultural Diversity

Brazilian festival in Herter Park / Herter Park Facebook

While designers of the built environment only improve at creating sustainable, technologically-savvy, and beautiful places, they aren’t succeeding at “creating belonging,” a feeling of “respectful co-existence in shared space,” argued Julian Agyeman, a professor of urban and environmental planning at Tufts University. More “culturally-competent” planners, landscape architects, architects are needed to create more just places.

In a keynote speech at the Congress for New Urbanism in Savannah, Georgia, Agyeman said “there is an equity deficit in the sustainability movement. The green movement is socially unjust.” Agyeman believes that in many cities “the old red-lining of neighborhoods have been replaced by green exclusionary zones — just a new form of socio-economic segregation.” Instead, true sustainability “involves justice — and equity in recognition, process, procedure, and outcomes.”

With true sustainability, it isn’t possible to have “spatial injustice,” in which life chances are not distributed in a fair way geographically. (Sadly, in the vast majority of countries, your zip code determines everything from your income to your life expectancy).

With true sustainability, public spaces are for everyone. He held up Reading Terminal Market in Philadelphia as an example of a “space of respect, engagement, and encounter.” Agyeman wondered whether we can design places like this anymore?

Reading Terminal Market, Philadelphia / Pinterest

Too often public spaces labeled as sustainable aren’t just. While the contemporary Complete Street movement is lauded as a way to make transportation systems more equitable — by providing equal access for pedestrians, bicyclists, and cars — complete streets that remove street vendors and spruce up public spaces with new amenities can end up killing the cultural and social lives of streets.

“Places have no fixed meaning; they are social as much as physical entities. Complete streets can disconnect streets from the social, structural, symbolic, discursive, and historical realities of a place.” Agyeman asked: “Who gets to say what a complete street is anyhow? They can’t be complete if they fail to include the livelihoods and economic survival of vendors.”

Park planning and design needs to be re-thought in terms of boosting cultural diversity, instead of just ecological diversity.

As an example, he pointed to a local park in Bristol, Massachusetts. At great expense, the park managers created a wildflower meadow in order to increase biodiversity. But the new garden had the effect of driving away Caribbean immigrants who used to spend time in the park. “They have a residual fear of places that could harbor snakes.” Aygeman said “if someone in the parks department was Caribbean, they would have known.” The question in instances like this is: “do we drop the cultural or social diversity or respect the cultural side?”

Given urban communities are evolving, we must better engage new immigrant communities in the planning and preservation of park systems.

In Boston, many immigrants “aren’t connecting with the old parks created by Frederick Law Olmsted. They just don’t resonate with them — and these groups, which are growing, could be deciding the future of Boston’s parks.”

Immigrant groups instead yearn for landscapes that remind them of home. In Boston, Herter Park draws immigrants from Latin and South America, because it provides spaces for extended family gatherings by a river, which feels familiar to them (see image at top).

Aygeman thinks landscape architects must intentionally design for immigrants and encourage encounters between ethnicities.

In Supekilen Park in Copenhagen, Denmark, teams of designers with BIG, Topotek 1, and Superflux, created a “controversial park” in a highly-diverse immigrant neighborhood where ethnic groups “could see themselves in the space,” but also encounter other communities. Each ethnic group in the neighborhood around the park had a designated space meant to reflect some aspect of their cultural identity.

Superkilen Park, Copenhagen, Denmark / Jens Lindhe

Parks-for-all like Superkilen may just be the start. Aygeman foresees a future in which landscape architects first do “deep ethnographic research to really understand a community before they get started.” Landscape architects trained in “cultural competency” then eliminate disparities in access to public space, creating true urban commons. “More diverse professionals who know what these new societies think” will partner with diverse communities to “co-design and co-create more just places.”

The result could be something like Medellin, Colombia, where a participatory approach rooted in the philosophy of “social urbanism,” led to the “urban transformation of the century,” in which the poor were given equitable access to all the city has to offer — parks, libraries, museums, and transit.

Retrofitting with Green Infrastructure

California Avenue Rain Garden, University of Calinfornia, Davis / Kevin Robert Perry

Why retrofit cities and suburbs with green infrastructure? Re-inserting the landscape back into the built environment helps us strike a better balance with nature, boost neighborhood health, and solve stormwater management problems. In a session at the Congress for New Urbanism (CNU) in Savannah, Georgia, a landscape architect, an urban designer, and a civil engineer offered fresh takes on why green infrastructure is so valuable.

According to landscape architect Kevin Robert Perry, ASLA, founder of Urban Rain Design, the issue is the sheer amount of impervious surfaces, the oceans of asphalt in our cities and suburbs, which can account for half of the built environment. “We need to get more water into the ground.” He said communities should take a “decentralized, natural approach” to getting more stormwater off pavement and into the ground, where it can recharge underlying aquifers.

In increasing levels of optimization, communities can maximize landscape along streets; increase their tree canopies; create park-like streets, sidewalks, and driveways; scale up networks of green, complete, streets; or build an “entire green envelope, covering buildings and streets” across the entire city or suburb.

But Perry noted the need to keep actual green infrastructure solutions simple and low-cost. His well-known Siskiyou Green Street in Portland, Oregon, cost just $20,000.

ASLA 2007 Professional General Design Honor Award. Siskiyou Green Street, Portland, Oregon / Kevin Robert Perry

Ellen Dunham-Jones, professor of urban design at Georgia Tech and author of Designing Suburban Futures, and her students collaborated with the Atlanta city government, as it begins to realize its vision of a new city design, which is rooted in Atlantans’ love of the legacy of Martin Luther King, Jr, who was born and raised there, and the city’s luxuriant tree canopy, which covers some 45 percent of the city. The design paints a picture of equitable growth in an urban forest.

Dunham-Jones and her students began to examine how a city expecting to triple in population could still maintain its tree canopy, with all its health and stormwater management benefits.

Beyond concentrating development in centers and corridors, so as to protect old growth trees, another way to do this is to retrofit trees into neighborhoods through novel regulations.

Using the Cascade Road neighborhood, a majority African American community in southwest Atlanta, as a study site, she sent out seven pairs of students to identify some options. Her team recommended re-planting or relocating trees off private property into nearby public conservation easements, and “fee-simple” donations of wetlands and flood zones that have mature trees to the city government.

“The idea is to move more trees into the public realm. We can protect them better if they are on public property; and we can also protect the rights of private property owners.”

She said Atlanta hopes to enshrine many of these ideas in a new, more stringent “nature ordinance,” designed to replace the current tree ordinance, which has relatively lax rules on tree removal.

And Paul Crabtree, a civil engineer who runs the Crabtree Group, concluded that those who are forging innovative green infrastructure solutions in communities should be considered “shock troops, highly-skilled soldiers on the front line, taking heavy casualties, even when successful.” After much persuasion and many grants, he managed to create an innovative “tree zipper” in the middle of a street in Ojai, California.

The Planning and Architectural Legacy of the Manhattan Project

Road-to-Los-ALamos
Road to Los Alamos, ca. 1943-45 / Los Alamos National Laboratory Archives

The Manhattan Project, the secret US government program that produced the world’s first atomic weapons during World War II, left a complicated legacy in its wake. It brought the second world war to a close, but laid the groundwork for the Cold War. It was responsible for the deaths of over 125,000 Japanese citizens, the majority of whom were civilians. It ushered in the atomic age as scientists and businesses sought ways to use “atoms for peace,” leading to advances in medical imaging, the rise of nuclear energy, and even “atomic gardening.”

It also gave us the cities of Oak Ridge, Tennessee; Richland and Hanford, Washington; and Los Alamos, New Mexico, cities that were created as part of the Manhattan Project and whose existence remained a closely-held secret during the war. These cities are the subject of Secret Cities: The Architecture and Planning of the Manhattan Project, an exhibition currently on display at The National Building Museum in Washington, D.C.

Aerial-View-of-Hanford
Aerial view of Hanford Construction Camp, ca. 1945 / U.S. Department of Energy, Hanford Collection

At a recent lecture, senior curator Martin Moeller delved into the planning, architecture, and cultural legacy of these cities — their lasting impact on the industries of the built environment. He began by pointing out that, in terms of design, there was little revolutionary about these towns. Precedents for planned communities existed in developments such as Olmsted and Vaux’s Riverside, Illinois; the Garden City Movement; and the work of Scottish biologist and city planner Sir Patrick Geddes.

What makes the cities of the Manhattan Project significant, however, was the scale of their design and speed of their construction. Moeller pointed out that, unlike earlier examples of community planning, these cities had to be entirely self-contained due to the nature of the work being carried out there.

In the case of Oak Ridge, architecture firm Skidmore, Owings & Merrill (SOM) was responsible for the design of an entire city that would be home to 75,000 residents by the end of the war.

Hutments at Oak Ridge / Southern Spaces

Moeller explained that SOM went from “being architects to being planners and civil engineers, and soon they were going to becoming construction engineers, interior designers, and even designers of the school curricula in the schools within Oak Ridge.”

In addition to being planned in utmost secrecy, Oak Ridge and other Manhattan Project cities had to be constructed at a breakneck pace. “During the height of the war, the contractors building these houses were turning over the keys to the government to one house every thirty minutes,” said Moeller.

The speed of construction was possible thanks to advances in prefabrication technology. Houses at Oak Ridge were constructed using Cemesto boards, a prefabricated product made of compressed cement and asbestos fibers, and were built in an assembly line fashion, a technique that developer William Levitt would later use in the construction of his Levittown developments.

Flat-Top-House-Oak-Ridge
“Flat Top” house, Oak Ridge, 1944 / National Archives and Records Administration

Given the speed at which these cities were constructed, one of the more remarkable aspects of their design is the inclusion of green, walkable community space. “This is extraordinary,” argues Moeller. “This is an emergency situation, where people are thinking that we are in a race against time, and we’re being careful to preserve large trees and create greenbelt spaces between houses.”

This also raises provocative questions about modern day development practices. If the planners of these communities were able to take the time to preserve existing natural features and integrate green space under extraordinary circumstances, why do we find it so difficult to do the same thing today?

There were darker aspects to these cities as well. Land for the developments was seized from existing residents via eminent domain; property owners were told that the land was needed for a “demolition range.” In Oak Ridge, this primarily impacted poor subsistence farmers. In Washington, the government seized land from the Wanapum people, a Native American group that traces its identity to the region and the Columbia River that runs through it.

Race also played a part in the story of these cities. For example, segregation was designed into the plan for Oak Ridge. African American residents were forced to live in “hutments,” small, single-room structures with minimal protection from the elements. The hutments were separated from the city and further segregated by sex, dividing up families and adding further insult to the indignity of being forced to live in substandard housing.

Life-at-Hutments
African American women hanging laundry in a hutment area, Oak Ridge, 1945 / Edward Westcott. National Archives and Records Administration

Despite a complicated social and political legacy, for Moeller, the urban design legacy of the Manhattan Project is clear. “The real thing to come out of this, in terms of architectural and planning history, is the emergence of the modern architecture-engineering-construction firm.”

By the end of WWII, SOM had grown to 650 employees, and would eventually become “arguably the single most influential corporate architectural firm in the post war era.”

In their work on Oak Ridge, SOM took on an expanded role as “architect, engineer, planner — all these things really beyond the scope of what architects had ever done.” Because of this experience, “they were uniquely prepared coming out of WWII to design for the new world, creating corporate campuses and communities on a scale that we wouldn’t have even been conceived of before.” They paved the way for the business model that would come to define the planning and design industries in the second half of the 20th century.

Secret Cities: The Architecture and Planning of The Manhattan Project is on display at the National Building Museum in Washington, D.C. through March 3, 2019.