Re-thinking wastewater landscapes: combining innovative strategies to address tomorrow's urban wastewater treatment challenges

Most major cities worldwide face urban water management challenges relating to drinking supply, stormwater and wastewater treatment, and ecological preservation. In light of climate change and finite natural resources, addressing these challenges in sustainable ways will require innovative solutions arising from interdisciplinary collaboration. This article summarizes five major urban water management strategies that bridge the fields of engineering, ecology, landscape architecture, and urban planning. A conceptual implementation of these strategies is demonstrated through a design for a small constructed wetland treatment system in San Francisco, California. The proposed decentralized system described in this article consists of a detention basin, vegetated and open free water surface wetlands, and ultraviolet disinfection. In wet weather, the system would detain and treat combined sewer discharges (CSD), and in dry weather it would treat residential greywater for toilet flushing and irrigation in a nearby neighborhood. It is designed to adapt over time to changing climatic conditions and treatment demands. Importantly, this proposal demonstrates how constructed wetland engineers can incorporate multiple benefits into their systems, offering a vision of how wastewater infrastructure can be an attractive community, educational, recreational, and habitat amenity through the integration of engineering, ecology, and landscape design.