By Amy Crawford
By 2030, more than half the global population is expected to live in cities, which researchers have predicted will cover 3 percent of Earth’s land surface — triple the area devoted to urbanized areas just 20 years ago. Meanwhile, we’re already using half the habitable land for agriculture. And with climate change making an ever-more-rapid impact, it’s imperative that the growth and development of what might be termed our “human habitat” — buildings, transportation networks, food systems — be sustainable, with minimal damage to ecosystems and to the planet as a whole.
As U-M President Mark Schlissel said last year in a message announcing the creation of the President’s Commission on Carbon Neutrality, “Climate change is the defining scientific, social, and environmental problem of our age.”
It’s a complicated problem, with many interdependent facets. On the front lines are architects and urban planners, among them Taubman College faculty, students, and alumni. They are studying ways to make buildings more sustainable, reimagining transportation and food systems, and ensuring that environmental justice also is social justice. And through the President’s Commission, they are working to help the university meet its carbon neutrality goal, an effort that could also serve as a roadmap to a sustainable future for humans everywhere.
In 2011, U-M set a series of goals for sustainability by 2025: reduce energy-related greenhouse gas emissions by 25 percent, cut on-campus transportation carbon emissions by 30 percent, and reduce landfill waste by 40 percent. Nearly a decade later, the university is making progress on these goals, but as the full impact of the climate crisis grew impossible to ignore, it became clear that U-M needed to do more. So last year, President Schlissel announced a goal of complete carbon neutrality.
It’s a tall order for a 200-year-old institution made up of more than 500 buildings, 50,000 faculty and staff, and 50,000 students. The first step was bringing people together from across campus — including representatives from Taubman College — to form the President’s Commission on Carbon Neutrality and discuss how the sprawling university can meet this ambitious goal.
“A lot of people don't understand what carbon neutrality means, exactly,” says Larissa Larsen, an associate professor of urban and regional planning and a member of the commission. “Unlike sustainability, it’s focused on energy production and fossil fuel use, so that’s a much narrower discussion.” To determine a baseline for carbon emissions, the commission created three scopes of greenhouse gas inventories based on source: emissions from U-M’s own energy production, those from the additional energy the university purchases, and those from all other sources. That third scope “is where difficult decisions must get made,” Larsen says. “One of our biggest challenges is determining what should be included in scope 3."
Scope 3 covers emissions from such things as the daily commute to campus to work or study and travel by students and faculty to share research findings or conduct fieldwork. But other, less-obvious elements carry a carbon footprint, too.
“We are thinking about anything related to food on all three campuses,” says Lesli Hoey, an associate professor of urban and regional planning and co-leader of the commission’s internal analysis team for food. U-M’s food service outlets are highly fragmented, with dining halls, Athletics, Michigan Medicine, and retail outlets operating independently. Fostering stronger connections could improve efficiency and reduce waste. Meanwhile, consumers must make changes that campus food purveyors are well-positioned to encourage, including nudging students toward choosing plant-based meals, composting their table scraps, and reducing waste. “A lot of research surrounds trying to change people’s behavior,” Hoey notes.
Changing behavior may also be key for the commission’s internal analysis team for commuting, led by Jonathan Levine, a professor of urban and regional planning who says that getting U-M students and workers to choose more sustainable modes of travel will require “a combination of sticks and carrots.”
Among the sticks may be a revision of parking permit policies. Rather than a large annual fee, the university might prompt drivers to think twice by implementing smaller daily fees. A potential carrot would be fast, higher-frequency bus routes that connect different campuses, as well as the university and community. But regardless of his team’s final recommendations, Levine argues that considering commuting at all is progress.
“It would be easy to say, ‘We're not responsible for the commute itself, that’s an individual's decision,” Levine says. “So it’s big and important to consider that commuting is part of the university’s carbon footprint.”
The bulk of U-M’s impact remains its buildings. In fact, notes Jen Maigret — an associate professor of architecture and co-leader of the commission’s internal analysis team for buildings, with Associate Professor Lars Junghans — the International Energy Agency has found that 40 percent of global energy consumption is related to building construction and use. “Reducing energy use, including heating and cooling, is one of the things that we're working on,” she says, “but we’re also considering the contribution of concrete and other materials, or what’s come to be called ‘embodied energy.’ And a lot of the greatest gains that you can get on a project come out of a very strong collaborative design team that, right from day one, establishes goals and expectations, and looks for simple or elegant approaches to achieving them.”
By the end of this year, commissioners will present Schlissel with a final report outlining goals, expectations, recommendations, and ideas that will set the course for the University of Michigan over decades to come. It may also chart a path that other institutions, businesses, and municipalities might follow, with the ultimate hope, in Schlissel’s words, that the effort will “marshal the intellectual resources and commitment of the U-M community to contribute to a more sustainable and just world.”
Since 10,000 B.C.E., humans have used concrete to construct everything from homes to monuments. In the 19th century, it allowed buildings to rise to new heights, and in the 20th century it let architects experiment with radical new ideas. Today, this mixture of lime-based cement, water, sand, and aggregates — little changed since ancient times — is the most common building material in the world. But it’s also the most polluting. Primarily due to the energy-intensive process of baking limestone to produce cement, concrete is responsible for as much as 8 percent of global carbon dioxide emissions. But a new generation of architects is exploring ways to make this important building material much less destructive — without giving up its miraculous capabilities.
“Green building has traditionally been all about reducing operational energy needs, and we’ve made huge strides,” says Jim Nicolow, FAIA, B.S. ’91, M.Arch ’95, a principal at Lord Aeck Sargent and the firm’s first director of sustainability. “New buildings are much more efficient now than even 10 years ago. But the big shift has been a recognition of the impact of all of the materials that go into a building, known as embodied carbon, and how we can improve that environmental footprint — especially with concrete.”
Part of the solution, Nicolow says, may lie with new materials, particularly so-called mass-timber, an engineered wood product that allows for taller structures than traditional timber.
“Timber sequesters carbon,” says Arash Adel, whose research as a postdoctoral fellow at Taubman College involves designing and building more efficient timber structures by employing computational design methods and robotic manufacturing techniques. “If you manage the life cycle, it has a positive impact on the carbon footprint of a building. And mass-timber allows for taller buildings. This is opening up new opportunities for timber construction, not only for houses and small buildings, but also for mid-rise buildings and for building types that may require large spans.”
Still, it is likely humans will always rely on concrete for our largest, tallest buildings. And some countries need a lot of it. That was made clear to architecture students who participated in a recent studio led by Assistant Professor Tsz Yan Ng and Associate Professor Wes McGee. The studio, sponsored by the global architectural, planning, and engineering firm SOM, took students to China for a whirlwind tour of the economic behemoth’s construction industry.
“China uses a lot of concrete,” McGee says. “Probably more than anyone else in the world. And their construction industry operates at a timescale that’s unfathomable.”
Back in Ann Arbor, the students studied the problems with concrete and considered solutions, including ways to apply 21st-century technology to this ancient material.
“We’re using digital fabrication and computational technique to rethink how we design and produce forms for casting,” explains Ng, who with McGee organized a 2019 symposium about innovations in concrete. “Part of this is looking at it from beginning to end, everything from the forms to the material itself to the scaffolds that hold the molds together.”
The most promising options are 3D printing concrete formwork or the concrete itself, says Mania Aghaei Meibodi, an assistant professor of architecture, who explains that both fabrication methods enable production of lightweight concrete structures or elements in any shape while reducing the material waste related to the traditional ways of fabrication. “3D printing will transform the concrete industry, the concrete element itself, and the way we design concrete structures in the future,” she says. An example is the Smart Slab project that she led at ETH Zurich, where her team created a concrete slab that is just 20 millimeters thick at its thinnest point and allows for the integration of infrastructures like sprinklers and electrical conduct.
“The amount of concrete we use is ridiculous,” Meibodi says. “It’s not even good for the structure. It makes it heavier. But new technology allows us to produce lighter, more complex forms. We not only have to change the way we produce concrete, so that there’s less pollution, but we have to change the way that architects design with concrete, so that the material is placed only where it’s needed and resources are utilized efficiently.”
These ideas for greener buildings can’t come fast enough, says Doug Farr, FAIA, B.S. ’80, a fellow of the Congress for the New Urbanism and president of Farr Associates, a sustainable architecture and urban design firm based in Chicago. In the late 1990s, his firm was among the first to attain a LEED (Leadership in Energy and Environmental Design) Platinum certification, one of the first and most widely adopted programs to make architecture more sustainable. Today, Farr notes, it’s become an expectation that high-profile projects will meet some level of LEED certification.
“LEED made a world of difference,” he says. “It changed the conversation. LEED is now a mainstream credential and skill set — for almost any architecture firm, it’s expected you’ll know how to design to LEED standards. But if we’re going to address the climate emergency, we need to go beyond the stand-alone building and ultimately beyond LEED. To progress, our firm helped to create LEED Neighborhood Development, a tool to certify entire places and building projects to the rigorous Living Building Challenge. So I think architects have a lot of power, but they need to have more awareness of it, and of how their work can accelerate the speed of change.”
Throughout most of the 20th century, transportation planning began with an assumption that economic growth would necessarily lead to more and more automobiles traveling through cities, as well as suburban and rural areas. A planner’s goal, then, was to ensure that all this traffic moved as swiftly and efficiently as possible.
“The transportation planning profession originated in an era when the car was king, and there was a lot of popular sentiment for public policies that would support auto mobility,” says Jonathan Levine, a professor of urban and regional planning. “So it was pretty easy to get going in that way. And once you’re doing that, it becomes a little hard to change. Engineering manuals, guidelines from the federal government — they all specify a certain way
of doing things.”
Despite the inertia, Levine argues that the field of transportation planning needs to shift from a “mobility logic” to what he calls “an accessibility logic.” Under that framework, the goal of transportation planning would not be speed or freedom from congestion, but “an increase in the value of the destination for a given investment of time and money. Under this notion, the purpose of travel is not moving, but the ability to reach destinations.”
He lays out this case in his latest book, co-written with Joe Grengs, chair and associate professor of urban and regional planning at Taubman, and Louis A. Merlin, of Florida Atlantic University. In From Mobility to Accessibility, Levine and his co-authors argue for a redefinition of success in transportation and land-use planning, which not only makes more sense to the person trying to get from point A to point B, but also offers a path toward
a more sustainable future.
Sustainability also goes hand-in-hand with safety, notes Linda Bailey, M.U.P. ’01. Formerly executive director of the National Association of City Transportation Officials, she joined Washington, D.C.’s Department of Transportation last year. As Vision Zero director for the District of Columbia, she is tasked with eliminating traffic fatalities and serious injuries by 2024. “I think that traditional traffic safety doesn’t see the connection necessarily,” she says. “Vision Zero is a much more holistic approach.”
A movement that began in Sweden in the 1990s, Vision Zero rejects the idea that a certain risk of injury and death is an acceptable trade-off for mobility. And crucial to realizing the goal of zero deaths is a rethinking of the automobile’s role in urban transportation.
“In transportation and urban planning, we’re still such servants to the automobile,” Bailey says. “But with the changes in technology and the changes in the way we build things, we can get to a point where the vehicle is the servant of the human, and not the other way around.” That could include reengineering roadways or reducing the size and speed of cars so they pose less danger to the people around them. It could also include placing a greater emphasis on transit; active modes like walking and biking; and newer forms of micro-mobility, like scooters. All of these efforts have the effect of reducing the amount of energy used to move people to wherever they are going, which can make transportation not only safer, but much less carbon-intensive.
As climate change upends weather patterns and increases sea levels and temperatures, it has become clear that the most marginalized members of society will bear the brunt of the impacts. As we work together to find solutions, how can we ensure that our efforts on behalf of the environment leave no humans behind?
“On a global scale, the poorest people in the world create almost no emissions — and yet they will be the first and worst affected by climate change,” says Larissa Larsen, an associate professor of urban and regional planning. Her research looks at how rising temperatures, diminishing water quality, and flooding affect cities’ poorest residents, particularly in the Global South. “Through research, we’ve learned that certain people — usually people of color or lower-income people — will disproportionately suffer the health impacts of pollution and extreme heat.”
Larsen’s research has focused on urban heat islands, where surface and air temperatures are elevated due to the higher heat-absorbing capacity of impervious surfaces. The phenomenon is exacerbated by climate change, which is now causing more extreme and longer heat waves. And it’s worse for poorer communities, who are less likely to have air conditioning and whose neighborhoods often lack so-called “green infrastructure,” like street trees and parks. It demonstrates how environmental justice is linked to social justice, Larsen notes.
“But meanwhile, social justice can conflict with sustainability,” she says, noting a recent call by Ann Arbor’s City Council members that new affordable housing should be carbon-neutral, which would place an additional burden on developers of much-needed housing for low-income residents. “By trying to do the environmentally right thing, you impede our ability to help people get housing.”
But social justice and sustainability need not always be in conflict.
“Environmental justice issues have always been intertwined with racial justice, and even with reproductive justice, gender issues, and other concerns,” says Gabriel Jones, M.U.P./M.S. ’17, a senior associate at the philanthropy consulting group Arabella Advisors, which works with foundations, companies, families, and individuals to maximize the impact of their giving. Jones says that some of the funders he works with have begun to think “more holistically” about how their gifts can have an impact on both the environment and on social issues. That’s also important for the urban planning profession, he says, noting that planning once played a role in destroying communities of color, particularly during the era of so-called urban renewal.
“It’s important to recognize the reality that planning has participated in unjust systems,” he says. “When you’re able to approach it from that lens, you’re even more attuned to each community’s vision for its neighborhood. And you can hopefully be a better advocate for social justice in different spaces that you’re in.”
That’s been a life’s mission for Kristin Baja, M.U.P./M.S. ’11, climate resilience officer at the Urban Sustainability Directors Network, a network of 238 local officials working on environmental, economic, and social justice issues. Recognized in 2016 by the Obama administration as a Champion of Change for her work on climate and equity, she now focuses on creating “resilience hubs:” facilities providing space and resources for a marginalized community to work toward economic development and equity goals, as well as toward reducing carbon emissions and improving its ability to adapt to a changing climate.
“Race is the greatest disparity in the United States,” Baja says. “I center all conversations around climate change in the reality of racism and prejudice to encourage a proactive, equity-centered approach. We are wasting our time if we’re not considering climate change and social systems together. We need to ensure we’re not progressing forward on one thing without considering who is impacted the most, how they are impacted, and how we can shift the power dynamics. We can’t take a top-down approach — our work toward sustainability must first be grounded in community well-being.”
The Los Angeles River runs more than 50 miles, from the mountains northwest of the city, through the San Fernando Valley and downtown L.A., and finally south to the Pacific Ocean. Once bordered by thick reed forests, its waters full of steelhead trout, the L.A. River today functions more like a giant storm drain. Lined with concrete by the Army Corps of Engineers after a disastrous 1938 flood, the river has long been seen as effectively dead. In recent years, however, it has been declared a navigable river, and some human residents have begun to think of the river and its banks as an ecological asset that could even help feed this sprawling city.
“If you look at how park-poor Los Angeles is, particularly in some of the communities along the L.A. River, well, we’ve realized the river can’t just be a flood channel anymore,” says Leigh Christy, FAIA, B.S. ’96, a principal in the Los Angeles office of Perkins & Will who leads the office’s pro bono work. She has spent more than a decade developing a series of visions that could transform at least one segment of the river for future generations. Her Urban Agriculture Green Infrastructure Plan, a partnership with the nonprofit River LA and incorporating substantive input from the City of Los Angeles, would remake a 660-acre area along the heart of the river into a hub for urban agriculture, with space for gardens, beekeeping, and even aquaculture, as well as a marketplace and facilities for processing so-called “value added” food products. Providing local jobs, affordable food, and testing new food-related innovation were goals, too. Christy says it’s all about resilience in the food system — providing options that leverage actions the local community is taking already.
“If you’re going to make something happen in this area, you need to define urban agriculture broadly,” Christy explains. “We’re talking about the full food cycle, because that’s what it will take to make something like this work in this community in a way that’s also truly sustainable.”
Urban agriculture has become a buzzy concept, notes Lesli Hoey, an associate professor of urban and regional planning whose research focuses on righting inequities in food systems. She describes how “large-scale, high-tech urban agriculture initiatives are growing around the country, but too often, they overshadow the long history of urban gardening and farming, particularly in communities of color.” Still, like Christy, she sees value behind the hype.
“From an environmental perspective,” Hoey says. “I think it has a huge role to play, if only in educating more people and bringing them closer to their food systems.”
Hoey’s research has taken her to Vietnam and Kenya, and she currently is looking at the nation of Bolivia and the state of Michigan as what she calls “prototypical cases,” or model food systems from which other cities, states, regions, or countries could learn.
“Both Bolivia and Michigan are ahead of the game in trying to shift toward either more health-promoting or more equitable or more sustainable food systems,” Hoey says. “In Bolivia, for example, the national government was one of the first to develop a massive effort to prevent malnutrition in children. In Michigan, it’s more of a bottom-up approach, in which cities and the state have responded to a lot of grassroots efforts to revive our local food economies and address equitable food access.”
Local food economies are increasingly important as climate change threatens global food systems, Hoey says, but the idea is also a bit of a throwback. As American cities grew in the 19th century, “food systems were integral to how they developed and were planned — ensuring people had access to food and connecting farmers with markets was a public function for a long time,” she explains. “It used to be something urban planners thought of as one of their basic functions, just like ensuring clean water.”
That changed as grocery stores replaced public markets and industrial agriculture replaced small farms, but as planners like Hoey and architects like Christy help cities develop more resilient food systems, the future might wind up looking more like the past.
That’s certainly true for the L.A. River, which — when Christy’s vision is realized — may begin to look and operate a little more like the vibrant, nourishing place it was before 20th century engineers encased it in concrete.