Do we only care for what is alive?
Reflections from the ‘Bringing Urban Rivers Back to Life’ conference.
‘Rivers are alive’, vibrated through the CARDIMED conference in Utrecht last week. But what if they were not, would they matter less? Some reflections on value, the commons, and why buildings, too, can be thought of as living systems.
‘Rivers are alive’ and why that statement works
Last week, on 22nd and 23rd of September 2026, researchers, practitioners, planners, policy makers and artists gathered at a beautiful location surrounded by a canal in Utrecht for the CARDIMED conference ‘Bringing Urban Rivers Back to Life’, organised together with Utrecht University’s Pathways to Sustainability programme. The conversations moved between daylighting buried streams, renaturing canalised riverbeds, governance and the idea of a shared manifesto for the rights to urban rivers.
Running through all of it was a statement: rivers are alive.
And the statement works and makes sense. Rivers are a part of and not apart from our human lives and they move, flow and shape landscapes, societies, economies and politics. It draws in not only scientists, who start reasoning about why and in what sense a river might be alive, but also the people who walk along a river every day, swim or fish in it, cross it on the way to work. People who speak of it as their river. Calling a river alive turns it from background into someone or something you can have a relationship with.
And yet, sitting in the sessions, one question kept returning to me.
Do we only value what is alive?
If we need a river to be alive in order to care for it, what does that say about everything we consider not alive? Do we value what is alive more than what we see as inanimate? Water, sediment, stone, air, soil minerals. If they are not alive, are they less valuable? Should they be respected less, simply because they do not seem to fight back?
On closer look, rivers do respond. They flood, they dry out, they erode banks and carry away what we put into them. They simply respond on timescales and in ways that we often do not read as a response; until the water is in the street. The question is not only philosophical. Ecosystems do not run on living organisms alone. In ecology, the structure of an ecosystem is the arrangement of both its biotic and abiotic elements. To those belong plants, animals and microbes, but equally water, minerals, light and the physical space in which they interact. The ecosystem services we depend on, from water purification to cooling and flood regulation, emerge from exactly these interactions. Take the ‘non-living’ half away and the living half has nothing to live in.
Ours, or everyone’s?
A second question followed closely: do we mainly care when we consider something ours? And do we care less when it belongs to the collective?
The attraction of ‘their river’ at the conference was that people felt ownership in the sense of belonging and attachment. Yet rivers, groundwater, air and urban climate are shared. They are commons, and commons are often treated as if they belong to no one. They are considered something to use, drain into or build over, while responsibility for their condition lies somewhere else. Often, we take more from the commons than what we give back, if we give something back. Elinor Ostrom’s work showed that this is not inevitable: communities can and do govern shared resources well when they see themselves as responsible for them. Perhaps what we need is to redefine what ‘ours’ means. Collective things and common goods are ours, but not only to use. They are ours to care for, and ours to provide for, too.
Everything moves, just at different speeds
A conversation with Elias Cuello, CEO of For Nature Construction and an electrical engineer by training, added another layer. His view was that everything is energy. Life exists through energy and happens at different timescales, in slightly different ways, but following certain rules. A river moves visibly, a stone over geological time, a building over decades of use, repair and renovation. And what we think, say and do also sparks energy that can inspire and move. Words and actions can change, affect and modify the systems we are part of.
You can take this theory to a spiritual level. But it also holds on to a very practical one, and it connects to thermodynamics. In my own research, together with colleagues, we described ecosystems and buildings as thermodynamically open systems: both continuously exchange energy, matter and information with their surroundings. Seen through that lens, the line between ‘living’ and ‘non-living’ looks less like a wall and more like a gradient in how systems organise and use energy. Clean water, for instance, holds more useful work potential (eco-exergy) than contaminated water. Through that potential it can support more life and more processes. The quality of something we call inanimate decides what can live with it.
The practical level of Elias’s point matters just as much: how we think and talk about things shapes how we act and decide. If a river is described as drainage infrastructure, we straighten it and put it in a pipe. If it is described as a living system, we start to ask what it needs to recover. Words decide what will be changed and what is allowed to stay. Why not think of buildings as living systems too?
This is where the river conversation links to EcoBUILD. If language shapes decisions, then the way we talk about buildings matters as well. We usually describe them as static, inert objects: a structure, an envelope, an asset. But a building is also an open system, constantly exchanging heat, water, air, materials and information with the city and landscape around it.
In a paper with Jaco Appelman and Maibritt Pedersen Zari, we argued that metaphors like ‘living buildings’, or buildings as ‘living systems’, can help move building practice towards regeneration. Design strategies which generate ecosystem services are what allow buildings to begin functioning like living systems. In a later article in Land, we proposed that buildings can become habitats hosting living, non-living and hybrid systems, and derived design strategies from how ecosystems work: providing space for ecologies, increasing multifunctionality, designing dynamic and open structures that exchange with their surroundings, and building symbiotic interactions between living and technical systems. With Marcus Fricke and colleagues, we also showed how ecosystem services are lost across a building’s whole lifecycle, and how much unfulfilled potential common green roofs and façades still have.
This thinking runs through my PhD thesis on weaving ecosystem services into building development processes. And it links buildings directly to rivers. In every roof sits a water catchment system. Furthermore, rainwater that runs off a sealed roof into a sewer, heat radiating from a façade, pollutants washed from a courtyard, all of it ends up in the river system. A building that retains, filters and slowly releases water, cools its surroundings and provides habitat is part of bringing a river back to life, even if it stands kilometres away from the bank.
From care to evidence Caring for something, a river, a building, a commons, becomes more durable when we can see what that care achieves. That is what EcoBUILD works on: a structured, open knowledge base that links building design strategies to the ecological and social benefits reported in scientific studies and real case-study buildings. Not to replace the question of what we value, but to make the consequences of our design choices visible, so that care can become part of everyday decisions rather than an afterthought. Maybe the most important question from the conference was not whether rivers are alive. It may be whether we are willing to treat what we share, be it water, soil, air, and the buildings we place among them, as ours to care for, whether or not it breathes.
If you’re interested in learning more
CARDIMED conference ‘Bringing Urban Rivers Back to Life’: https://mission-adaptation-portal.ec.europa.eu/news-events/events-0/cardimed-conference-2026-bringing-urban-rivers-back-life-2026-09-22_en Hecht, K., Appelman, J., & Pedersen Zari, M. (2023). Buildings as Living Systems – Towards a Tangible Framework for Ecosystem Services Design. In Design for Climate Adaptation (UIA 2023), Springer. https://doi.org/10.1007/978-3-031-36320-7_19 Hecht, K., Ortega Reboso, A., van der Vegt, M., Appelman, J., & Pedersen Zari, M. (2024). Ecologically Regenerative Building Systems through Exergy Efficiency: Designing for Structural Order and Ecosystem Services. Land, 13(9), 1375. https://doi.org/10.3390/land13091375 Fricke, M. M., Hecht, K., Vollmer, M., & Lang, W. (2024). Ecosystem Services Guiding Built Environment Design – Understanding the Impacts of Building Practice on Ecosystems and Their Fundamental Contribution to Human Wellbeing. In Design for Climate Adaptation (UIA 2023), Springer. https://doi.org/10.1007/978-3-031-36320-7_24 Hecht, K. Towards ecologically functional buildings: weaving ecosystem services into building development processes (PhD thesis, Utrecht University). https://research-portal.uu.nl/en/publications/towards-ecologically-functional-buildings-weaving-ecosystem-servi/ EcoBUILD platform demo: https://www.youtube.com/watch?v=NdFSIIp4SNI
Author: Dr Katharina Hecht I am an environmental scientist and ecologist working at the interface of ecology, urban design, and sustainability science. My research focuses on ecosystem services, regenerative design, and how ecological knowledge can inform sustainable buildings and cities.