This dissertation is the result of a two-year research project on the Environmental Protection Agency's (EPA) Urban Waters Federal Partnership (UWFP) program, which aimed to improve water quality and promote environmental justice (EJ) outcomes for marginalized communities. The analyses I present draw from qualitative research conducted in four different US cities involved in the partnership project. My findings reveal specific failures within the UWFP program as well as the frictions between participating organizations and government entities that the project often intensified. My focus on tensions between advocacy groups adds complexity to previous portrayals of EJ activists and of the EJ movement itself. In addition, my reflection on shortcomings of institutionalized environmental justice asks what strategies are needed for engaging more productively with the EPA. As my research draws into focus some of the paradoxes and constraints the environmental justice movement faces, I suggest paths forward for EJ advocates, for EJ scholars, and for EPA staff. Lastly, I include a chapter on research ethics that considers impacts of environmental trauma and better practice for activist research, as a complement to the previous investigations.