In this essay, I focus on the remarkable process through which Mumbai’s urban administration has continued to release its sewage, largely untreated, into the Arabian Sea. I show how it does this by rendering sewage both legally and materially ambiguous. I urge an attention to the processes of legal and material ambiguation, through which ‘slow violence’ is unevenly administered in Mumbai. Building on the work of Jacqueline Best, I argue that ambiguity does not simply leave open improvised forms of technocratic administration; ambiguity also defers bureaucratic activity in particular domains, while permitting activity in others. Taken together, the municipal administration mobilizes ambiguity so as to evade rendering toxicity an actionable problem of urban living and distributed social vulnerability in the city.