Since 2011, Chinese environmental authorities have undertaken a project of "occupying" online spaces, with a particular focus on social media like Weibo. These activities have been analysed alternatively as a promising attempt to improve environmental governance by increasing citizen engagement and transparency, or as a new tool of control over online environmental discourses. However, empirical research into the practices of state microblogs is rare, and the implications of their emergence for local environmental governance remain poorly understood. Using a combination of online and offline investigation methods, this paper analyses the use of microblogs by 172 local environmental authorities in Shandong Province, whose multi-level EPB microblogging system is seen as a model for other provinces, testing whether this system improves environmental governance, and whether this objective is impeded by practices aimed at controlling online environmental discourse. We find limited evidence of improved environmental governance that would be attested by enhanced information disclosure and active citizen engagement. Instead, EPB communication appears mostly insular, and obstructed by floods of diversionary content and propaganda. We suggest that while these behaviours are likely driven by misaligned state incentive structures and fears of triggering social unrest, they also support the goal of discursive control by occupation.