This research project explores the potential of greywater reuse as a sustainable solution to growing water scarcity concerns in British Columbia. Despite being traditionally viewed as rich in water, BC is increasingly facing drought conditions as well as rising water demand, highlighting the need for decentralized water management strategies. Greywater, which is used water from showers, bathtubs, sinks, and laundry, represents a less-utilized resource that can support household irrigation and urban food production. The primary challenge addressed in this project is the restrictive regulatory framework in BC, which classifies all greywater as high-risk sewage, which is costly and limiting for homeowners. This contrasts with more flexible, risk-based systems used in jurisdictions like Seattle and Arizona. By analyzing greywater characteristics, pathogen risks, environmental impacts, and climate conditions, this research demonstrates that a tiered regulatory approach is scientifically justified and technically feasible.

The proposed solution centers on a low-cost Laundry-to-Landscape (L2L) system combined with subsurface mulch basin irrigation. This approach minimizes human exposure, promotes natural biological treatment, and aligns with BC’s wet climate conditions, helping mitigate salt accumulation. The project also considers crop suitability and emphasizes source control practices to reduce environmental risks. Through this work, key learning outcomes that include a clearer understanding of greywater’s risk profile were identified. This includes the importance of climate-specific design, as well as the role of policy in enabling sustainable practices. The project recommends that BC adopt a tiered regulatory framework like Seattle’s mirroring similar climate conditions, to allow safe, accessible greywater reuse while maintaining environmental and public health protections.

Next Steps

Although this project is not currently being implemented at a community scale, it provides a technical and policy foundation that could inform future programs of the potential of greywater reuse. The findings have been shared with the CityStudio partner to possibly contribute to ongoing discussions around sustainable water management as well as policy development in BC. The recommendations, particularly the adoption of a tiered regulatory framework and low-cost residential systems, have practical potential for real-world applications if taken forward by municipal or provincial stakeholders. Future work could involve collaboration with local governments to test small-scale greywater systems or develop educational resources for homeowners. Currently, this project serves just as a research and policy proposal; however, there is potential for continuation. This can be through further academic research, stakeholder engagement, or integration into sustainability initiatives focused on water conservation as well as urban food security.