Tara Webster is a microbial ecologist and environmental engineer. She is collaborating with Noah Fierer and Balaji Rajagopalan to improve our understanding of the microbial processes in biosand filters. Biosand filters hold great promise to provide clean drinking water in both developed and developing countries. Effective pathogen removal relies on the activity of a complex microbial community within the filter. However, little is known about the factors that shape microbial community structure and function in these systems. Currently, filter start-up and maintenance are based on empirical observations, leading to highly variable performance. To address this variability requires a better understanding of how filter design impacts microbial community development and pathogen removal. This research will determine how biotic and abiotic design decisions can shape microbial community structure to improve biosand filter performance.