A novel assessment of the environmental and economic impacts of washing operations and water management practices at bus depots

Water crises, fuelled by population growth and anthropogenic climate change, are increasingly threatening many diverse regions, including Europe. While water management is a priority for many sectors, the transportation industry suffers from a significant dearth of academic literature and standardised best practices. This dissertation addresses this gap by evaluating novel water management systems designed to reduce consumption and enhance sustainability, specifically bus-washing operations for transport operators. The research was conducted through three case studies at bus depots located within Europe that participated in the European Commission-funded project LIFEH2OBUS. The findings from these case studies and complementary data were used to develop the first-of-its-kind Environmental Footprint Tool for bus washing facilities and the LIFEH2OBUS depot intended to represent the standard European bus depot. Three scenarios were created: Business-as-Usual (BAU), a Wastewater Recycling System (RS), and a combined Rainwater Harvesting and Recycling system (RHR). The scenarios’ environmental impacts were assessed using the aforementioned tool, and economic viability was analysed through a cost-benefit analysis. Results indicate that while both novel interventions significantly reduce environmental impacts compared to BAU, the RHR system offers the highest environmental performance. However, the RS system proved significantly more economically cost-effective than the RHR, and both outperformed the BAU. However, the study finds these technologies may not be optimal for depots with smaller fleets, suggesting a need for further case studies and possibly scaled solutions. The findings highlight that achieving water-efficient operations necessitates interindustry collaboration, supranational standardisation, and a shift in government policy. By aligning academic research with transport operations, this study provides a framework for stakeholders to mitigate water scarcity while maintaining economic viability in the transportation sector.