River Rail
On Salt Creek: Flows of Rivers and Peoples
Combining lab work, trash gathering, and art making to tell a river's story. Featuring ecologists Timothy Hoellein and Denise Bruesewitz and author Mary Ellis Gibson.
The Thalweg
Salt Creek is just west of Chicago. Like many urban streams in the upper Midwest, it is situated on a flat landscape, with slow-moving water, a sandy streambed, and incised banks. Many urban streams in this region have well-preserved streamside vegetation that grows in areas set aside for parkland. This designation serves the practical purpose of much-needed flood protection in a place with low relief and plenty of rain. Recreation and natural areas around the stream are a benefit to the community but can also exacerbate littering and illegal dumping—both of which are apparent at Salt Creek.

This image (fig. 1) combines the geologic and the astronomical. The horizontal layers on the canvas allude to geologic strata, representing the long-term deposition of natural material and litter within Earth’s sedimentary record. The intricate rusting of the barrel lid and bowl communicates the slow disintegration of litter in the environment as these decomposing objects are incorporated into sediment layers. They also convey an appearance of weathered planetary or moonlike surfaces. Additional spheres in the horizontal stripes are “echoes” of past litter that have disintegrated away, though their imprints in the geological record are permanent. I like that these additional spheres suggest a dynamic interplanetary system. The composite image is meant to reinforce the sense of longevity of litter impact in Earth’s geological record. The associated graph (fig. 2) is a summary of all the types of litter we encountered at Salt Creek, where the barrel lid and bowl were found.
I am an aquatic ecologist studying water pollution in streams and rivers. I became an artist by accident. For the past 10 years the focus of my research has been “trash”—I am interested in measuring the sources, movement, and biological interactions of litter in rivers in Chicago and other urban areas. “Anthropogenic litter,” the term we use to describe trash in the environment, represents a diverse array of items made up of plastic, metal, rubber, and textiles. Litter comes in many sizes, from large pipes and shopping carts down to microscopic plastics. The research projects that my students and I have conducted have involved many measurements of anthropogenic litter in rivers.

As a byproduct of this scientific research, my lab periodically fills up with piles of trash collected during our studies. After our first set of projects, I was fascinated by the appearance of some of the litter items—they seemed to tell a story. I reached out to a few acquaintances in the art department at my university to ask whether they or their students would be interested in repurposing our trash to create artwork. No one took me up on this offer, so I myself felt compelled to craft artistic expressions from our trash. My work as an artist has become a complementary extension of my scientific research.
I use the litter collected from our research projects to convey many of the same conclusions as our scientific papers. Making art also frees me to see new and unexpected connections in my research. I hope this combination of art and science will expand the audience for the topic and carry these ideas into diverse media:
1. Longevity
Depending on where it ends up, trash made of plastic, metal, and other types of material can persist in the environment for hundreds of years or longer. Anthropogenic litter is one component of the permanent human imprint on the geologic record, part of the emerging concept of the Anthropocene, the epoch in which human activity defines the very nature of the planet. To communicate an idea of litter’s longevity in our waterways and elsewhere, I wire particular bits of litter onto the frames of canvases where I have painted abstractions of geologic strata, or of satellite images taken of natural landscapes. My goal is to convey the persistence of litter as it becomes part of the ecosystems where it falls. I like to imagine this combination as among the archaeological discoveries made by future generations or other civilizations. As they find, date, and attempt to explain the geologically rapid increase in litter at this point in Earth’s sedimentary record, what will they conclude about our culture’s values and our relationship to the natural world?
2. Graphic data / graphic art.
I pair many pieces with a graph that displays data we generated from the litter in the artwork; the titles indicate where the material was found. It is important to me that the graph shows that the litter items are also data and have contributed to a systematic, scientific assessment. Graphs represent a fundamental tool of scientists, who in creating them make artistic choices in their presentation of data, in a way distinct from but akin to how an artist works on a canvas. Therefore, scientists are innately equipped with an artistic “toolkit” for communicating results. Scientists often describe graphs that are especially effective at conveying complex ideas as “elegant,” an artful term that illustrates how communication is a common goal of science and art alike.
3. Transformation
The rusting, twisting, and fragmentation of litter in the environment generates compelling shapes that are a product of human and natural forces. The dynamic nature of the surfaces can easily be overlooked when the litter is in the environment. By placing the litter within a new context on a canvas, viewers are able to carefully examine the beauty of its decay. The cracks, algae, and rust bring it alive and speak to its continuous, incremental disintegration. In fact, we conduct studies to measure the microbial life on trash—the mixture of bacteria, algae, and fungal organisms that colonize litter is unique compared to natural surfaces such as rocks and leaves. This means some novel microbial communities grow on litter in comparison to other natural surfaces, some of which contribute to its breakdown into smaller pieces.
4. Rivers: arteries or kidneys?
The distinguished stream ecologist Dr. Judith Meyer has stated that in the past, rivers were the foundation for the location, growth, and health of cities. They “served as the arteries of the continent.” She goes on: “today they are used instead as kidneys—processing and purifying the wastes of an industrialized society.” The accumulation of trash in our rivers is a symptom of this fundamental conflict. Clean freshwater is a universal imperative for human health, so why do humans across the world dump trash into rivers? In doing so we defer dealing with our litter and assign this task to those downstream and to later generations. I hope to convey the irrational behavior of humans toward our fundamental need for clean water, and to speak to our ethical responsibility to the others who will have to clean up our mess.
—Tim Hoellein
Tributary
Dear Tim,
Your work and this conversation have driven me back further and further to basic questions. What is a river? What are data? What is the power of metaphor? How does our thinking about rivers, about the daily and geological work of Earth’s processes, necessarily happen through conceptual metaphors, metaphors that create the conditions of thought and therefore the conditions of both scientific investigation and art? As a person who studies literature, specifically 18th- and 19th-century literature and empire, I find that entering this conversation has led me—surprisingly—back to my own historical period.
For me your work as a scientist and an artist has important epistemological, ethical, and aesthetic claims. First, it has implications for the ways we think of rivers as living beings/systems. The very word “system” seems to stand in the way of a river being understood as a “being.” As you note, people find it difficult to give ecological “systems” the respect granted to the idea of a being. But why not take rivers or ecological systems as beings?
Many cultural and religious traditions ascribe forms of being to rivers. Rivers have recently been given legal—that is, juridical—personhood. The Ganges and the Yamuna in India and the Whanganui in New Zealand are all now legally persons. The people of Toledo, Ohio, in the wake of a toxic algae bloom on Lake Erie—their source of drinking water—have voted by a two-to-one margin that the lake (like human beings) has a legal right to “exist, flourish, and naturally evolve.”
My musing about rivers as beings and legal persons led you to reply that for you, “every place in nature is sacred. The difference is in the degree to which they have been defiled. My inclination is to serve those places. I know their current state is temporary because sacredness is inherent and restoration inevitable. This is the foundation of my work.” So the littered streambank in Chicago and the pristine or nearly pristine riverbank in a national park are for you equally valuable, equally important. And these places or systems are sacred, or, as a philosopher might say, valuable as ends in themselves.
This orientation toward the living world around us, using “living” in its broadest sense, has political implications as well. If we think of systems as beings, we can join a venerable tradition of activism dating back to the 18th-century movement for the abolition of slavery. In the 18th century opponents of slavery argued that enslaved people, like other humans, were beings in the fullest sense of that word—and therefore were understood as having either the same human rights as other human beings or the same souls as other humans or both. In each case, juridical right or religious obligation meant that an enslaved person must be treated as a legally and ethically valued being and that the condition of slavery was inhuman, inhumane, and not legally binding.
Similarly, if rivers are beings, then killing them—by slow chemical death and other forms of human-devised destruction—is immoral and illegal. And it is no accident that the descendants of enslaved people and indigenous peoples often must live beside and within the floodplains of the most polluted of rivers. The abolition of slavery, the opposition to the genocide of indigenous peoples, and the protection of rivers—we should think these forms of care in the same thought.
We can even go so far as to say that many governments and corporations and individuals are trading in the lives of natural systems—the lives of the other beings of our planet—with the same moral abandon that they do and did trade in the lives of other humans.
I’d like to hope that this way of thinking about rivers—rivers as beings—isn’t metaphorical or anthropomorphic. Using anthropomorphic language to make natural beings into humans doesn’t effectively decenter the human or call humans to account for their actions. Rivers have for years been described anthropomorphically—if we speak of them as arteries, surely we’re thinking of human arteries and, implicitly, of trade as the lifeblood of societies. You’ve pointed to Judith Meyer’s more recent discussion of rivers as kidneys, with the potential for purifying the detritus and pollutants of the planet. I like this metaphor quite a lot. If we think, though, of what the linguist George Lakoff would call the metaphor’s entailments (the ideas a metaphor brings along with it), the implications are a little scary. If rivers are the kidneys of the continent’s body, then the continent—like an old alcoholic—might be depending upon fragile kidneys to repair a history of abuse. And the metaphor is highly ironic in a culture where diabetes and kidney disease have reached epidemic proportions. How can we expect humans to respect the continent’s body more than their own?
But if we resist the anthropomorphic metaphors for rivers, we can grant to rivers through our imaginations what they already have—their own being and their own value. One of the greatest 20th-century books about rivers, Norman Maclean’s A River Runs Through It, concludes with the poignant sentence: “I am haunted by waters.” If we think anthropomorphically about rivers—as arteries of the slave trade or as the kidneys of our failing economic/agricultural system—and if we then rethink, allowing the river to have its own being, we might have to admit that it is we who have transformed rivers into haunted places. When we deny the value of rivers or of other humans, we create the violence that begets haunting.
As the Waterkeepers of Standing Rock have so forcefully made clear, it is humans who have an obligation to rivers, not rivers to us.
With all best wishes,
Mary Ellis
The Hyporheic
Rivers collate information about humans. They are powerful forces, capable of shaping landscapes and shrugging off constraints like dams and armored banks in times of flood. But they can also shape our thinking, our art, and our histories. In our consideration of rivers here, it is also important to recognize a quiet power that rivers possess—the power rivers give us to reflect on ourselves and our communities. We can capture chemical signals in river water that tell us what we eat and what drugs we take, what we use and discard, or what lengths we will go to for manicured lawns. Such knowledge expands our connection to rivers; as they collect information about our lives, they also connect us to our creative selves.
The signatures of humans in river water can be sensitive enough to reflect what people do in different cities or on different days of the week. Day-to-day signals from Kenting, Taiwan, show a cocktail of caffeine, ecstasy, and ketamine entering the local river alongside a steady input of Tylenol during Spring Scream, a pop music festival. We can find the unique isotopic signal of human-made nitrogen carried on the wind to remote alpine lakes. We encounter here the concept of rivers (and lakes) as sentinels and integrators of change first shared by Craig Williamson, with the idea that waters that fall on our parking lots and lawns, that flow through cornfields or sewers, pick up the signature of that place and eventually find their way to a river, lake, or coastal system where they slow down and pool. In these waters, we can collect a snapshot of what is happening on land. In the realm of science, we can also use this framework to understand other human impacts, like rising water temperatures or the presence of DNA snippets from spreading invasive species. If we turn this back around to think about our personal and societal connections to rivers, these signals might tell us things that sadden us or (and) point to inequalities. Rivers carry burdens of industry and agriculture on the land that surrounds them. They carry a sense of place that does not hide undercurrents.
Like Tim, I am an aquatic ecologist who dedicates a lot of time to measuring how humans change the way that rivers work. Years ago, as a graduate student, I received the advice that our work as scientists is to ask questions, collect data, and try to answer our questions dispassionately—in other words, we should not appear to be interested in the fate of these ecosystems (or beings), we should not be overly concerned lest our science be seen as biased. In the intervening years, we have seen a wave of disbelief in science, a willingness and a desire to disregard data as we make decisions that impact our environment. These issues are messy for scientists, and I think we all have to find our own answers about how we ought to engage in such messiness, beyond reporting our data. There is something really powerful about a scientist engaging in creative expression. Such an endeavor is genuine and human, and it can help connect people to their rivers. Rivers quietly compile information about who we are and transmit that signal back to us. If we move beyond quantitative data and embark on an investigation of river flows—encompassing the ecological system, the human, the historical, the political—we can combine all these ways of knowing a river and so be better stewards of both our communities and our ecosystems.
—Denise Bruesewitz