As a teenager, David Sedlak was mesmerized by a novel. “It happened while I was in high school, a time when many young people are ‘abducted, by science fiction ,” this American civil and environmental engineer from the University of California at Berkeley tells SINC .
That book, however, was different, ambitious, like nothing I had read until then: in Dune (1965), the writer Frank Herbert built a whole universe from the combination of elements of medieval culture —an empire in ruins mediated by feudal relations, monastic orders and legends of the advent of a messiah— with touches of high technology such as spacecraft, genetic manipulation, and eugenics.
Beyond the galactic adventures and the eternal struggle between good and evil in this saga, which has just been adapted to the cinema again in a film by Denis Villeneuve , it was a long meditation on deeper issues, a commentary on the rise of religious fundamentalism and the madness of clinging to power, as well as an allegory on colonialism and the destruction of important ecosystems for the acquisition of fuels (the sought after ‘spice’ in history refers directly to oil).
At the same time as the biologist Rachel Carson denounced the excessive use of pesticides in her book Silent Spring (1962) and inaugurated contemporary environmentalism , Herbert deepened global awareness of environmental concerns from fiction.
In addition to its environmental message that would make it one of the first works of the now popular subgenre cli-f (or climate fiction ), Sedlak was fascinated by a Costume piece for this story set in the distant future on a desert planet called Arrakis .
The protagonists [of the novel] wore suits that captured moisture and waste produced by the body, such as urine and feces, and recycled them so that the user could hydrate through a tube connected to his mouth
David Sedlak, Civil and Environmental Engineer, Bekerley University
As Sedlak recalls, one of the most intriguing aspects of the novel that caught his attention “was that the protagonists wore special suits that captured the moisture and waste produced by the body , such as urine and feces, and recycled them so that their user could hydrate through a tube connected to their mouth ”.
Herbert called them stillsuits (or distillation suits) and, although he did not elaborate on their technical details, they were the evolution of the gigantic and clumsy suits of the astronauts of his time that allowed them to survive in uninhabitable environments such as outer space.
“That image stuck with me forever, even though I didn’t live in a desert area,” says Sedlak. “I grew up near the water in Oyster Bay, New York. I spent a lot of time outdoors around the bay. Back then, it was announced that water could one day become as valuable as gold. Dune planted a seed in me that, without knowing it, grew over time ”.
Civil engineer David Sedlak wants to apply the idea of Dune distillation suits to cities to conserve water / University of Berkeley
The city as a living organism
Sedlak forgot about Dune and the stillsuits for many years . Over time, he devoted himself to studying and developing new technologies to provide an abundant and safe water supply to future generations, especially as droughts become more frequent in certain regions of the world.
To do this, this researcher leads a team in which he studies the mechanisms through which chemical products are degraded in advanced water treatment plants [19459003 ] to how to improve the desalination processes of marine water for consumption.
Until a few years ago, he reread the novels that make up Herbert’s space epic with his daughter. “The rediscovery of this treasure from my youth made me think: Could we build a distillation suit for an entire city?”
The idea of considering the city as a body, in fact, was not entirely new. It was born in the nineteenth century but settled in the sixties of the last century. It was known as ‘ urban metabolism ‘: it consisted of conceiving a city as a living organism that feeds on food, generates waste, needs energy and even gets sick if it is not taken care of . And dies.
Sedlak believes that in cities, as in the costumes in Herbert’s novel, a closed system could be created without the need to go out and fetch more water. It would only be enough to recycle it
Sedlak believes that in cities, like the costumes in Herbert’s novel, a closed system could be created without the need to go out and fetch more water. It would only be enough to recycle it.
Stories about water scarcity are very powerful in fiction. Over and over post-apocalyptic movies, like Mad Max (1985) and Tank Girl (1995) or Quantum of Solace (2008), and novels, such as The parable of the sower by Octavia E. Butler, [19459008 ] Water knife by Paolo Bacigalupi or The memory of water from Emmi Itäranta , 19459003] recall how the climate crisis exacerbated droughts and anticipated the emergence of conflicts around our most valuable resource.
“In many countries, unless you are very poor, you have enough water to drink, cook, take a shower, wash your car , so it does not seem that we live in one of these dystopias ”, says Sedlak, who is also the author of the book Water 4.0: The Past, Present, and Future of the World’s Most Vital Resource .
However, “water scarcity or droughts have a great impact on everyone’s life because they can affect the food supply or alter the landscape. In California, we are experiencing terrible fires and smoke reaches us every day. The lack of water is making it difficult to extinguish them. Those dystopian nightmares of a future without water or of fights over the last straw are becoming an increasingly tangible reality for millions of people in the world ”, comments this engineer.
The water crisis is not a threat. In many parts of the planet it is a reality. The UN estimates that by 2025 some 1.8 billion people will live in areas with ‘water stress’ . The extreme drought on the Colorado River has led the US Government, in recent weeks, to push for mandatory water cuts in Arizona and Nevada.
The Paraná River in Argentina —the second longest in South America after the Amazon— is suffering the longest drought in 77 years. Brazil, for its part, declared itself a water emergency in May.
With his team, Sedlak explores how cities will have to adapt to cope with the effects of climate change, population growth and the struggle for water resources.
The researcher indicates that this can be achieved at different levels. Just as many people have solar panels on the roofs of their houses and do not need to connect to the electricity grid, a building or a home can capture rainwater and recycle it . “The systems that allow this are improving,” he says. “ reverse osmosis technology used to remove salinity from seawater is increasingly accessible.”
But it is not enough. Sedlak believes that it is necessary to completely abandon centralized wastewater treatment plant schemes and build distributive recycling plants throughout the city.
Among the proposals are the capture of rainwater and its recycling, reverse osmosis that eliminates salinity from seawater, and smaller wastewater treatment plants distributed throughout the city
It indicates that “the systems we use to move water around cities can be very inefficient. In some countries, between 20% to 40% of the water is lost before reaching homes ”.
Furthermore, “a lot of energy is required to move the water several kilometers from the plant to the user. Instead of having one or two plants in a city of one million or ten million inhabitants, one could have 20, 30, 50 smaller treatment plants with greater autonomy and that can operate independently. And instead of having a full-time staff of operators, they could be run remotely with sensors and actuators, ”he stresses.
Sedlak proposes a distributed system of wastewater treatment plants in cities. / Brave Blue World.
Innovations with resistors
This new proposed planning consists of a transition to next generation water systems and at the same time a continuation of a repeated cycle of growth, failures and reinventions of urban water systems that has occurred over the last 2,500 years: piped water systems and sewers built by ancient Romans were replicated in European cities that they were growing very rapidly during the first wave of global industrialization in the 19th century.
Drinking water treatment was the next revolution: it stopped the spread of waterborne diseases – such as cholera and typhoid fever – and generated benefits for unimaginable health.
This was followed by the standardization of wastewater treatment plants after decades of decline in the rivers, lakes, and estuaries that surround cities. In Windhoek, capital of Namibia —one of the driest countries in Africa—, they have produced drinking water from treatment of their wastewater since 1968 .
In Singapore , where drinking water is a national security issue and half of their current water supplies are imported from neighboring Malaysia, they combine desalination plants, recycling of wastewater and efficient collection of rainwater through a network of drains, channels, rivers, rainwater, collection ponds and reservoirs.
However promising they may seem, these strategies may meet with resistance. “Drinking water that falls on the roof and using it is something that many people accept,” says Sedlak.
“When it comes to recycling wastewater, people get nervous. What we have noticed in California, Australia and Singapore, places that have pioneered these systems. For this reason, it is necessary that we familiarize ourselves with these technologies ”, says Sedlak
“But when it comes to recycling wastewater, people get nervous. What we have noticed in California, Australia and Singapore, places that have pioneered these systems. Therefore, it is necessary for people to become familiar with these technologies. There must be transparency and also trust in those who provide the water. Some communities have been successful in creating these recycling systems. In others, where governments are not trusted, they failed ”, says the engineer.
There are cultural reasons that explain these rejections. In religions such as Judeo-Christian or Islam, certain taboos prevail regarding interacting with waste.
The example of the International Space Station
Changing these old conceptions will take time but communities and governments can learn from successful examples, such as the International Space Station (ISS. By its acronym in English). At 400 km from the earth’s surface, a closed-loop system captures the astronauts’ wastewater, such as urine, sweat or even the humidity of their breath. Then impurities and contaminants are filtered out of the water. The end product is potable water that can be used to rehydrate food, wash or drink.
On the ISS a closed loop system captures urine, sweat and even moisture from astronauts’ breath. Then everything is filtered and turned into drinking water that can be used to rehydrate food, wash or drink
“The system may sound disgusting,” says chemistry Enid J. Contes from Ames Research Center from NASA – but water recycled on the ISS is cleaner than what most people on Earth drink ”.
The treated wastewater can also be used for food cultivation . “That has been more accepted around the world,” recalls Sedlak. “It has been done for hundreds of years. In Israel, all sewage is diverted for crop irrigation. Also in China and parts of the United States. And it’s not just to grow grasslands for livestock. In California, we have a water recycling project in Monterrey where the treated wastewater is used for growing strawberries and lettuce ”.
Like Sedlak and his team, around the world all kinds of scientists, engineers and innovators are working to develop new technologies and strategies that generate, supply and provide drinking water on which we humans depend so much.
In his documentary Brave Blue World , the Irish biochemist and producer Paul O’Callaghan tells that in certain regions of Africa there are ‘[ 19459061] harvests ‘water from the atmosphere. In northern California, they are experimenting with systems capable of ‘ hunting ‘ mist to capture up to 30 liters of drinking water in 24 hours, while a Danish company seeks to apply recycling technology from the ISS on Earth.
As Sedlak points out: “This wide range of innovations that allow us to safely collect, recycle and purify water is no longer a matter of science fiction.”