This paper responds to recent calls for deeper scrutiny of the institutional contexts of citizen science. In the last few years, at least two dozen civil society organizations in New York and Pennsylvania have begun monitoring the watershed impacts of unconventional natural gas drilling, also known as "fracking." This study examines the institutional logics that inform these citizen monitoring efforts and probes how relationships with academic science and the regulatory state affect the practices of citizen scientists. We find that the diverse practices of the organizations in the participatory water monitoring field are guided by logics of consciousness- raising, environmental policing, and science. Organizations that initiate monitoring projects typically attempt to combine two or more of these logics as they develop new practices in response to macro-level social and environmental changes. The dominant logic of the field remains unsettled, and many groups appear uncertain about whether and how their practices might have an influence. We conclude that the impacts of macro-level changes, such as the scientization of politics, the rise of neoliberal policy ideas, or even large-scale industrial transformations, are likely to be experienced in field-specific ways.