Self-organisation in environmental service delivery is increasingly being promoted as an alternative to centralised service delivery. This article argues that self-organised environmental service delivery must be understood in the context of legal rules, especially environmental legislation. The article’s aim is twofold: first, to understand the changing relationship between the government and citizens in self-organised service delivery, and second, to explore how self-organised environmental service delivery complies with environmental quality requirements stipulated in legislation. The empirical study focuses on wastewater management in Oosterwold, the largest Dutch urban development that experimented with self-organisation. The results show that while individual wastewater management was prioritised and implemented at scale, the applicable legal rules were not adequately considered and integrated. Consequently, the experiment led to a deterioration of water quality. The article concludes that the success or failure of self-organisation in delivering environmental services such as wastewater management critically hinges on ensuring compliance with environmental legislation.