Ross Vander Meulen is far too young to remember the 1948 Donora Smog, when air pollution over a Pennsylvania steel town grew so toxic that it killed 20 people and sickened thousands more. At 23, he doesn’t remember the Los Angeles of the 1950s, when small children sometimes fainted from the smog. It seems unimaginable to him that, in 1969, a sheen of toxins coating Ohio’s Cuyahoga River burst into flame.
The former civil and environmental engineering graduate student has grown up in an America relatively free of the unchecked pollution that was commonplace in the early and middle 20th century. And it didn’t happen by accident.
Today’s comparatively clean environment is due largely to the efforts of the generation that came of age in the 1960s and 70s, which includes Vander Meulen’s graduate advisor, Glen Daigger. Daigger, a professor of civil and environmental engineering, remembers back to the days in the late 1960s when his generation, already outraged by the Vietnam war, looked around at a poisoned country and decided that enough was enough.
“Rivers were burning, air pollution was horrible,” he said. “There was a gut-level feeling that humankind, through the things we were doing and the way we were living our lives, was destroying the planet. We were destroying it for other living things, but also for ourselves.”
At U-M, almost exactly 50 years ago, that feeling manifested itself in The Teach-In on the Environment, an event that helped crystallize the public consensus that something had to be done. On March 11, 1970, a 50,000-strong cadre packed the newly christened Crisler Arena to kick off what has been called “The most famous little-known event in American history.”
The lineup of speakers and events seems almost impossibly diverse today – from Ralph Nader to Republican Michigan Gov. William Milliken, heads of Dow Chemical and General Motors, even folk-rock star Gordon Lightfoot and the Chicago cast of “Hair.” Events included the “trial” and execution-by-sledgehammer of a 1959 Ford and the dumping of thousands of non-returnable pop cans at a Coca-Cola bottling plant.
The four-day teach-in was more successful than anyone – especially its organizers – could ever have imagined.
“It was an idea whose time had come,” said Doug Scott, who in 1970 was a graduate student in the forest recreation program of the School of Natural Resources and co-chair of ENACT, the group that organized the teach-in. “It wasn’t threatening, it was something that everybody could get behind. And I think it appealed to our nature not only in terms of wanting to keep the place we live clean, but also to our American style of wanting to be involved and present…this was a positive thing that people could do and do widely.”
The event was an audacious gamble that went far beyond the modest series of lectures that was originally planned. Scott believes that it gave the public, politicians and the media an idea of what was possible and the sense that this was the time to make it happen.
“The way I was raised was, ‘If you’re going to do something, don’t ever make small plans. Do it right,’” Scott said. “Nobody ever said, ‘That won’t work.’ Nobody ever said I shouldn’t go and approach the president of the university about [the teach-in]. We never limited ourselves on the scale that we should pursue.”
The months and years that followed the teach-in saw a flood of legislation that rebooted the nation’s thinking about the environment, making protection of the natural world a national priority for the first time. The passage of the Clean Air Act and establishment of the Environmental Protection Agency in 1970, the modernized Clean Water Act passed in 1972 and the Clean Drinking Water Act passed in 1974 were perhaps the most prominent examples.
Today, half a century after the first Earth Day, Vander Meulen’s generation is at a similar inflection point. Floods and wildfires are alternately drowning and scorching vast swathes of the planet, while the United Nations’ Intergovernmental Panel on Climate Change found in 2018 that we have just 12 years to make massive changes if we’re to avoid the worst consequences of climate change. Those consequences could include massive sea level rise, food and water scarcity and potential political unrest.
For a generation still in the early stages of adulthood, the uncertainty can be an overwhelming burden. And U-M professor Meghan Duffy has seen its effect on her students first-hand. The professor of ecology and evolutionary biology considers the climate change lecture in her introductory biology course to be the most important material she teaches. But she found that it was causing anxiety attacks in her students, leaving them feeling dejected and hopeless rather than empowered to make change.
“There’s a danger in having the instruction emphasize climate catastrophe,” she said in an interview with the Washington Post. “It’s tempting to say how bad things are, how much we need to stop it. But at some point, you’ve accidentally said this is a foregone conclusion.”
So she updated her approach to focus on solutions as well as problems. And her students, as well as their generational cohorts, are doing the same. In September of 2019 they organized the Global Climate Strike, attended by around four million mostly young protesters in cities around the world. Across U-M, students are taking part in a series of 50th-anniversary Earth Year events to explore the challenges they face.
In the engineering college, Vander Meulen and others are channeling their energy into building a different future for themselves, and they’re thinking big. They envision a built world that aims to learn from nature rather than conquering it, recycling resources over and over again instead of relying on constant inputs of energy and materials. They see crises like climate change and water scarcity not as an end but as a beginning, and they’ve found opportunity in tired 20th-century systems that are increasingly showing their limits.
“There’s a changing of the guard with the infrastructure, now that things are getting old and need repair and attention,” he said. “It’s opening doors for new technologies to be implemented. It’s the combination of the scientific growth and knowledge about how these things operate and just the opportunity – the infrastructure needs a reset, so to speak. It’s really about changing the conversation, right?”
DOING WATER DIFFERENTLY
Holed up in a chilly concrete basement at the Ann Arbor Wastewater Treatment Plant, civil and environmental engineering PhD candidate Avery Carlson is surrounded by a multi-colored maze of massive pipes, valves and gauges as well as the sulfurous tinge of sewer gas.
But his attention is focused on the slender rack of equipment tucked in a corner. A delicate network of tubing connects several clear, waist-high cylinders filled with partially treated water from the plant. The dark gray water is the untreated liquid that remains after solids are removed from sewage. The gently swirling water contrasts sharply with the gurgle and roar of the surrounding machinery.
“Most of this stuff came from Amazon,” he shouts above the noise, gesturing toward the rack. “It’s pretty amazing how much we can do without a lot of big, expensive machinery.”
That, in a way, is the point. Plants like the one Carlson is standing in were largely designed in the 1970s and 1980s, when the world’s population was less than half what it is today. They do a good job of making sewage clean enough so that it can be thrown away without harming the environment. But they require massive inputs of energy and chemicals – water treatment is one of the most expensive and energy-intensive aspects of running a modern city. And because the water that comes out is still too dirty to be reused, water systems are dependent on nature to provide a constant supply of fresh water at the other end of the process.
This model worked well enough in the 20th century. But with today’s hotter, dryer world and a population that’s expected to swell to nearly 10 billion by 2050, it’s stretched to its limit. Humans are going to need to do water differently – and soon.
Carlson, Vander Meulen and the rest of his team, led by Glen Daigger in CEE, are working on it. They envision a water treatment system that works more like nature, doing away with the idea of wastewater altogether and recycling the same resources again and again. The key, explains Carlson, is to stop thinking of used water and the nutrients that come from human waste – mostly carbon, nitrogen and phosphorus – as pollutants. They’re simply resources that happen to be in the wrong place at the wrong time.
“There is enough water, we just need to manage it differently,” Daigger said. “Today, when we need more water, the first question we ask is, ‘Where can we get more groundwater or surface water?’ What if we asked, ‘Where is there used water?’ or ‘How can we use less water?’ If we ask different questions, we’ll get better solutions.”
A key to making that happen is to devise ways of treating water that, unlike today’s systems, don’t require massive inputs of energy and chemicals. Making it economically feasible to purify water to a higher standard could fundamentally change water treatment, enabling us to reuse water rather than having to constantly find new sources.
“As a society, I think we need to look at [water treatment] more as a system and less as a linear process,” Carlson said. “If we understood that the water we drink today came from somewhere upstream and that our wastewater gets passed to another town downstream, I think we’d be a lot smarter about how we use and treat it.”
Today in the Ann Arbor treatment plant, Carlson is tweaking the chemical and biological variables of a lab-scale system that purifies water using activated biofilms – thick skins of pollutant-eating bacteria that are cultivated on specially designed membranes.
Within a year, the team plans to have the technology up and running in a prototype treatment plant that’s slated to be built on an island in the Yangtze River near Nanjing, China. Called Eco Hi-Tech Island, the development is being built to showcase new environmental ideas, of which the activated biofilm system is one.
The plant is to be built by Dajiang Environment Corporation and funded through a joint effort between the Chinese and Singaporean governments, with ongoing research done by a team of Michigan Engineering professors and graduate students. The first full-scale application of the new technology, Daigger sees the Nanjing project as an opportunity to dramatically accelerate its development. The team is in the final stages of securing funding for the plant, which could be finished in a matter of months once construction begins.
“China is essentially in the process of doing what the U.S. did in the 1970s through about the mid-1980s in terms of putting their basic wastewater treatment infrastructure in place,” Daigger said. “They’re implementing more new systems than any place in the world. So, working with them could mean that the world begins to see the benefits of this technology in five years instead of 20 years.”
Using bacteria to treat wastewater isn’t a new idea, but Carlson explains that today’s systems rely on mechanical aeration, which requires massive air pumps and huge inputs of energy. It’s an inefficient way to cultivate bacteria that only partially purifies the water, sometimes requiring the addition of costly chemicals to finish the job.
The new system takes a much more precise approach to cultivating beneficial bacteria. Instead of just blasting in air bubbles, the membrane feeds the bacteria directly through the biofilm, enabling tighter control over their environment and making it possible to specifically cultivate the most useful bacteria. It’s also estimated to use about two-thirds less energy.
The bacteria gorge themselves on the pollutants, and as they reproduce and settle out of the water, they carry nutrients like phosphorus with them. Because those nutrients are in a relatively pure form, they can be recycled into products like fertilizer, not only keeping them out of landfills but potentially generating a new revenue stream. And because bacteria are doing so much more of the work, costly chemical additives aren’t necessary.
Carlson says a less resource-intensive method for treating water could also redefine the logistics of water treatment, reducing reliance on large municipal treatment plants. That could enable a decentralized system made up of smaller plants that process water for individual neighborhoods, or even single buildings.
Decentralized systems could be less costly, more resilient, and could be customized to the treatment needs of individual areas, enabling them to recycle non-potable water instead of relying on nature for a constant supply of fresh water. They could even bring cleaner water to remote areas and developing countries where large, centralized systems aren’t practical.
Carlson is optimistic about the potential of the team’s technology, but both he and Daigger are also realistic about the fact that it could take decades to change the paradigm in a field as risk-averse and far-reaching as water. In their view, that makes the work all the more urgent.
“They say it takes about 50 years for a technology to get from point A to point B,” Carlson said. “But you have to start somewhere. What we’re trying to do is take real, tangible steps. It’s going to take lots of different concepts, lots of different ideas, and my technology isn’t going to be the one thing that all plants everywhere use. It’s a piece of the puzzle.”
BUILT TO LAST
Water is the most widely used substance on Earth. The second most widely used substance is concrete. And not without good reason – concrete is cheap, plentiful, versatile and durable. Worldwide, 10 billion tons of it are produced every year. That’s about enough to pave the entire state of Ohio with a smooth, fresh, 1 ½-inch thick patio.
But the way concrete is produced and used today makes it one of humans’ most carbon-intensive activities, emitting 2.8 billion tons of climate-warming carbon dioxide gas every year. If concrete were a country, its carbon emissions would be eclipsed only by China and the United States.
Those massive emissions have made built infrastructure, like water treatment, a target in the battle to rewrite the contract between humans and the planet. And, similarly to Daigger’s team, the groundwork is being laid in large part by a generation that sees its future at stake.
The team includes civil and environmental engineering assistant research scientist Duo Zhang, who came to U-M in 2018 by way of China and Canada, parlaying a background in bridge engineering into a position as a building material scientist. After seeing the increasing effects of climate change in the environment around him, he felt he needed to do something to help.
“Where I grew up in Shandong Province in China, snow used to be common, but now there’s very little,” he said. “When I moved to Montreal for graduate school, I began to notice that every winter was warmer than the last. It was very obvious, and it made me think about how my field is one of the biggest emitters of CO2. That got me thinking about ways to use concrete to take carbon out of the atmosphere instead of emitting it.”
The team, led by civil and environmental engineering professors Victor Li and Brian Ellis, is working on a radical new system that could turn concrete into a reusable resource that lasts hundreds of years and removes carbon from the atmosphere instead of emitting it.
Li has been in concrete and construction for decades. If there’s a board or institute that relates to concrete, Li has probably been on it. But he shares Zhang’s sense of urgency and doesn’t mince words about his industry’s outsize contribution to climate change. Li is the James R. Rice Distinguished University Professor of Engineering and E. Benjamin Wylie Collegiate Professor of Civil Engineering.
“We’re the culprit,” he said. “The built environment – roads, bridges, airports, seaports and other buildings – contributes about 60 percent of the world’s carbon emissions when you consider not just production and construction, but also operation and maintenance. We plan not only how these products are made, but often how they’re designed and used. So we have the opportunity to dramatically reduce the Earth’s carbon footprint.”
Li envisions a built environment where most concrete infrastructure is built from high-strength, reusable, modular precast concrete blocks. He has already developed a concrete formula that’s hundreds of times stronger than ordinary concrete. Called ECC, it can bend and flex under stress, instead of cracking as today’s concrete does.
The material is currently being tested in buildings and bridges, and Li believes it could be used to make precast blocks durable enough to last hundreds of years. They would be manufactured in massive quantities and warehoused until needed. Computer software would convert architectural drawings into the right type and number of blocks, which would then be shipped to the construction site and quickly assembled using a largely automated process. When it comes time for renovation or demolition, blocks could be disassembled and sent back to the warehouse until they’re needed again.
If this all sounds a little familiar, it’s because Li’s system draws inspiration from a 20th-century system that we’re all familiar with: Lego.
“Lego is very attractive because you can make many things from the same set of blocks, you can quickly assemble and disassemble,” Li said. “This is the same idea. It would enable us to use the same concrete over and over again instead of knocking whole buildings down and starting over when we want something new.”
Because of their long lifespan, the blocks could also be used to sequester carbon. Zhang is working on a process that sequesters carbon dioxide gas inside precast concrete by rethinking the curing process that’s commonly used today.
“Precast concrete is cured in giant chambers, using steam,” Zhang explains. “We’ve replaced the steam with carbon dioxide gas, which mineralizes into calcium carbonate as it diffuses into the concrete. In lab-scale tests using purified carbon dioxide gas, we’ve sequestered an amount of carbon equivalent to 30% of the weight of the cement used in the concrete. That’s very significant. The process actually makes the finished concrete harder and denser, and because it works at room temperature, it uses less energy than steam curing.”
Zhang is setting up a custom-built, room-sized reaction chamber in the GG Brown Building on North Campus where he will scale up the process, tweaking variables like chemistry, temperature and timing. The ultimate goal is to make the process work using the carbon dioxide waste gas that’s generated by activities like burning coal or manufacturing cement.
“Using waste gas is complicated because it takes longer to diffuse into the concrete than pure CO2,” Zhang said. “But the reaction chamber will give us the opportunity to refine the process by testing on a scale that wasn’t possible before.”
Several commercial firms are also working on carbon sequestering processes, and Li envisions that the final solution will incorporate a combination of innovations.
Li’s bendable concrete was developed under U-M’s MCubed program. The concrete system’s carbon sequestration research is funded in part by the United States Department of Energy and is also part of U-M’s Global CO2 Initiative, led by Volker Sick. It is one of several of the Global CO2 Initiative’s bold research projects, which also include efforts to turn carbon dioxide emissions into household materials and renewable fuels.
“If you look at what really makes a difference, what moves the needle, it’s ideas that are substantially beyond reach,” said Sick, who is an Arthur F. Thurnau Professor of Mechanical Engineering and DTE Energy Professor of Advanced Energy Research. “In almost all cases there are holes, problems to solve, and maybe we’ll solve those ourselves or maybe the vision will motivate someone else to solve them. But if you always play it safe, you’re not going to make the dramatic changes that are needed. We can’t afford to wait 50 years before this is all up and running.”
LET’S DO THIS
The plans to remake the world’s water treatment and building systems are just two of the environmental initiatives underway right now at Michigan Engineering. Calling them audacious would be a massive understatement. But, perhaps similarly to their predecessors in the 1970s, those behind them believe that the planet is at an all-hands-on-deck moment.
They’re also mindful of a lesson from the first Earth Day: Don’t be afraid to think big. Plans that look outlandish at first often seem less so as time passes. It’s something that both Scott and Daigger learned first-hand decades ago.
“If you look back 50 years, behavior has absolutely changed,” Daigger said. “In 1970, you could go into almost any room and people would be smoking. That’s almost totally gone now. People wear seat belts, they recycle. Behavior does change. The question is, does it change enough?”
Vander Meulen and his cohorts are doing all they can to ensure that it does; for them, the stakes couldn’t be higher. They realize that their efforts may only amount to a push on the larger wheel of history. But science is optimistic by nature, and they’ve found strength in the realization that their future is something to be shaped, not feared.
“I love the idea that we can apply concepts of chemistry and science and engineering all together and benefit the environment, benefit people, benefit public health. I think it’s just that combination of impact that we have and our responsibility to really care for our resources in the world that we live in.”