In the face of growing social-ecological challenges, multiple forms of expertise must be brought to bear in environmental problem-solving. As such, community-based science has been touted as a potential way to "democratize" scientific knowledge production, allowing for multiple sources of expertise to be harnessed and for learning across stakeholders to occur in new ways. The extent to which this occurs, however, is mediated by a variety of factors. Focusing on the context of a dam removal and river restoration initiative in the Western United States, we leverage "community science literacy" as a conceptual lens to critically interrogate if and how multiple forms of expertise are taken up through community-based science toward the goal of watershed revitalization. Based on an analysis of empirical evidence collected from interviews, ethnographic observations, and project artifacts, we found that local residents in the watershed demonstrated robust forms of situated local knowledge that they often leveraged toward the work of science. This occurred through processes of coordination work, which were mediated by opportunities for individuals to shift between roles, the contributions of brokers and boundary spanners, and issues of power, status, and rank. While individuals demonstrated and shared their nuanced local knowledge, dominant science still structured if, when, and how this was taken up in the project. Ultimately, we suggest that leveling hierarchies in community-based science--and affording broader publics greater epistemic agency in shaping the work of science--is key to fostering social-ecological transformation through science learning in informal settings.