For the Green River Project, artist Olafur Eliasson infused a non-toxic powdered dye called Uranin into the rivers of major urban centers, including Bremen, Germany (1998); Moss, Norway (1998); Los Angeles, USA (1999); Stockholm, Sweden (2000); and Tokyo, Japan (2001). The dye caused the rivers to turn a vibrant green, appearing suddenly and without warning, and thus highlighting the interdependent and complex relationship that exists between humans and nature, the natural and artificial, and between spaces and those who dwell within them. The project was unsanctioned, created guerilla-style, and unaffiliated with any institutional organization.
As art historian Madeleine Grynsztejn explains, Eliasson's "perceiver-dependent" works emphasize "active corporeal vision" and the "kinetic involvement" of the viewer. For Eliasson, The Green River Project sought to address the way in which "a lot of people see urban space as an external image they have no connection with, not even physically" and thus the project "was really about showing people, in this city, as they walk by, that space has dimensions. A space has time. And the water flows through the city with time. The water has an ability to make the city negotiable, tangible." In other words, rivers act as an ideal site for a re-consideration of the "turbulence" that characterizes life in urban centers. Eliasson also wanted to gain insight into "how the river is perceived in the city. Is it something dynamic or static? Something real or just a representation? I wanted to make it present again, get people to notice its movement." He says, "I was interested in the reaction of the people looking at the water [...] and the way this would change their perception of the city."
Speaking about his relational oeuvre as a whole, Eliasson has stated that "...the activities or actions of [the] user in fact constitute the artwork," and, furthermore, that "art and culture [...] have proven that one can create a kind of a space which is both sensitive to individuality and to collectivity. It's very much about this causality, consequences. It's very much about the way we link thinking and doing ... And right in-between thinking and doing, I would say, there is experience. And experience is not just a kind of entertainment in a non-causal way. Experience is about responsibility. Having an experience is taking part in the world. Taking part in the world is really about sharing responsibility."
For Eliasson, de-contextualizing this work, and not allowing it to be pre-conceived of by the viewer as an art project, was crucial. In an interview with art historian, critic, and curator Hans Ulrich Obrist, Eliasson describes an earlier project (Proposal for a Park, 1997), which he believes "didn't work" due to the public's prior awareness of the project as an "art" project. In his view, this preconceived notion of the project as "art" leads the viewer to see the work as a painting, rather than as "some kind of modification of the urban layout." Eliasson believes that The Green River Project, at least in Stockholm, was a success in this regard, stating: "That day, when the people in Stockholm looked at the river - to them, that the water moved was a surprise. The city wasn't a postcard! Not knowing it was an artwork was important. If people knew beforehand there wouldn't be the same discussion." Indeed, the key product of this project was discussion itself, discussion through which urban citizens could share their views on what constitutes the city, and could debate and hypothesize together about what possible reasons there could be for the river to change color in this way. Eliasson's aim was to provide an engaging experience that was "infinitely variable" for individuals, yet simultaneously shared amongst members of the community.
Without institutional affiliation, The Green River Project prompted action, interaction, and engagement, rather than the passive, liminal mode of viewing which so often characterizes a museum or gallery visit. Eliasson stated, "I want the museum visitor to understand that institutional ideology and display is in itself a construction and not a higher state of truth." Eliasson believes that "the museum and exhibition scene too often makes the public passive, instead of stimulating it ... There's a reversal of subject and object [in the Green River Project]: the viewer becomes the object and the context becomes the subject. I always try to turn the viewer into what's on show, make him mobile and dynamic."
This intervention has been praised by many, yet many spectators at all locations reacted with distress or fear, likely due to the fact that the violent green hue of the river provoked "alarming associations with environmental disaster." The amount of panic that developed in some instances was so great that it led Eliasson to decide to abandon such guerilla-art installations after 2001.