Separately collected urine is an attractive potential fertilizer because of its high nutrient content, low cost, and inherent linkage of urban wastewater management and peri-urban agriculture. Urine from waterless urinals was applied to corn and lettuce plants to examine the impact of urine application rates and frequency on plant growth and soil parameters. In both corn and lettuce experiments, urine application significantly (p < 0.05) increased growth and leaf production relative to control plants. More frequent applications led to lower soil cation exchange capacities for corn and higher soil nitrogen content for both crops. Based on preliminary implementation calculations, waterless urinals at the University of São Paulo (USP), School of Arts, Sciences, and Humanities campus could lead to over 1,500 m³ of water saved and 360 m³ of urine produced on an annual basis. These experiments and modeling results are discussed in the context of scaling up urban urine collection, transport, and fertilization in São Paulo, Brazil.

Currently, it is important to develop strategic frameworks to support the selection of sustainable resource recovery solutions. This study applies a new framework for planning, implementation, and assessment of resource recovery strategies for a full-scale wastewater treatment plant (WWTP) in São Paulo megacity. The framework comprises several steps based on case study-specific data and information from current literature. Data were collected from various sources: a survey with a wastewater treatment utility, national and regional databases, and review of local regulations and international literature. Treatment configuration, wastewater and by-products composition, potential demand (for water, energy, and phosphorus), stakeholder identification, and local legislation were thoroughly discussed regarding decision-making on resource recovery. Scenario analysis was used to explore suitable nutrient and energy recovery measures based on indicators. Biogas recovery and sewage sludge composting showed more favorable conditions due to similar experiences in the area and robust legislation. The proposed framework is a simplified tool, and its application can support managers to get information on resource recovery and how to plan such initiatives in easier ways to facilitate wiser decision-making, and better operation and management. The results on framework use and refinement can guide potential applications in other contexts and stimulate public policy formulation and further research.