In the middle of the Biesbosch National Park in the Dutch wetlands, where rivers weave through islands and reed beds, sits Biesbosch MuseumEiland. The museum, founded in 1984, was reimagined in 2015 as part of a massive Dutch water management program: 4,450 hectares of the Noordwaard polder were “depoldered” — turned back into a floodplain to help protect cities like Rotterdam from rising river levels. Within this transformed landscape, the museum itself became a showcase for living with water.
Instead of building a conventional wastewater plant, designers Studio Marco Vermeulen installed a system that feels almost poetic: a forest of native willows that filter the museum’s wastewater. “Water safety was the key reason for the development of the Biesbosch Museum Island,” says Studio Marco Vermeulen. “Sanitary wastewater is purified through a willow filter: the first in the Netherlands and an acknowledgement of the wicker culture of the Biesbosch”. The willows absorb the wastewater, including nitrogen and phosphate, which help the trees grow. Purified water is returned to the wetlands, creating habitats for birds and aquatic life.
In the face of mounting water stress, museums and cultural institutions are rethinking how to manage one of their most overlooked resources: wastewater. Conventional treatment plants are costly, energy-intensive, and require high levels of technical expertise. By contrast, soft wastewater treatment systems harness natural processes — wetlands, vegetation, soil, and microbes — to purify water with minimal energy, low maintenance costs, and far fewer chemicals. These solutions turn waste streams into landscapes that sustain life, biodiversity, and resilience. They also align with the United Nation’s Sustainable Development Goals (SDGs) for 2030, in particular SDG 6 (Clean Water and Sanitation) and SDG 15 (Life on Land) when it comes to water use.
In Arizona, another institution has taken its own measures, adapted to its own local climate.The Arizona-Sonora Desert Museum in Tucson reuses treated wastewater to irrigate gardens. In fact, 96% of its irrigation water comes from the wastewater treatment facility on the property. In its newest buildings - the Warden Oasis Theater and a new classroom for the Art Institute - also use rooftop water harvesting. Set in the Sonoran Desert, this museum replaces potable water with reclaimed flows, ensuring that even in one of North America’s driest ecosystems, green spaces remain lush while conserving scarce freshwater.
Trees in the Netherlands, reclaimed irrigation in the desert… No matter the environment, for museums wastewater can be more than hidden infrastructure — it can be transformed into a visible, regenerative system.
NEXT IN Summit is the event promoted by ACCIONA Cultura that brings together international leaders in the cultural field to share experiences, discuss ideas and analyze the challenges that will shape the future of the cultural industry.