To date, Marccus has primarily worked to understand how social processes and development patterns create hazardous human-built environments, vulnerable infrastructure, and the related risks in urban stormwater management and flooding. Other work has focused on technological disasters, namely fertilizer explosions, and structural damage assessments and recovery trajectories, as well as cascading events such as wet-weather events that overwhelm sanitary sewers and cause overflows, household backups, and contamination. His work emphasizes participation and action that uses methods including photography, visual inspection, and environmental sampling (e.g. , waterborne bacteria). For example, he developed a participatory assessment technique for infrastructure (PATI) that provides a community-based approach to assess the capacity and physical condition of stormwater and other infrastructure systems (e.g. transportation, utility poles, etc.). This application of community science was the first of its kind connecting flood risks from stormwater runoff to the infrastructure systems that are supposed to provide physical protection.