Waste to Fertilizer at the UBC Botanical Garden
Creating a closed-loop system, returning solid and liquid waste back to ecosystems in the form of nutrient-rich soil and fertilizer.
The UBC Botanical Garden, in partnership with the Biogenic Architecture Lab at the UBC School of Architecture and Landscape Architecture (SALA), has developed a proposal to incorporate a state-of-the-art mushroom-based composting toilet system at the entrance of the canopy walk. The composting toilet will not only provide a better experience to the user but create a closed-loop system returning solid and liquid waste from the toilet back to the ecosystem in the form of nutrient-rich soil and fertilizer, all while better aligning with the Garden’s goals of environmental stewardship. Funding from the Campus as Living Lab program will enable initial testing of the mushroom-based composting toilet during Spring 2024. To leverage these research funds, the Botanical Garden is currently seeking funding to transform this project into a long-term replacement of an existing chemical toilet that must be serviced weekly throughout the year.
Benefits of Composting
Composting toilets are a proven alternative to flush and chemical toilets, enabling onsite conversion of solid and liquid waste to valuable fertilizer that can be used to enrich local soils. Composting toilets operate naturally, without the need for water, electricity, or other inputs. It is estimated that the project will generate approximately 600L of valuable soil and 2000L of liquid fertilizer per year that can be used for operations and maintenance at the Botanical Garden, reducing overall reliance on energy-intensive fertilizers in keeping with ecological sustainability goals at the garden.
Incorporating New Research: A Phased Approach
The project incorporates innovative research at SALA and UBC Microbiology to develop the MycoToilet, the world’s first composting toilet to use mushrooms and thermophilic microorganisms to break down waste naturally and efficiently. The first phase of the project consists of a 6-week pilot project to test the MycoToilet at the Botanical Garden, which will be funded through the Campus as a Living Lab program at UBC. The toilet enclosure at the Botanical Gardens will aid in the full-scale development and testing of the MycoToilet with the goal of expanding its use beyond that of the Garden to provide solutions for contexts such as remote communities in Canada and refugee camps without access to centralized sewerage systems.
Project Team
Lead Researchers
Joseph Dahmen
Steven Hallam
Research Assistants
Isobel McLean
Lorena Polovina
Juan Santana
Collaborators
UBC Department of Immunology and Microbiology
Chris Moraes (McGill University)
Sponsors
Campus as a Living Lab Grant
UBC SEEDS Sustainability
BioProducts Institute
Visualization concept for the toilet enclosure at the UBC Botanical Garden
Proposed location of toilet enclosure
Exploded axonometric drawing showing enclosure structure
Enclosure section
Site section