The arrival in India of an internationally mobile discourse extolled “the market” as the best and most efficient allocator of resources and provider of urban services. The career of this idea in Mumbai reveals a surprising history of how the water department’s century-old system of careful mapmaking and record keeping was abandoned—a decline in which the debates over privatization have themselves been deeply implicated. The privatization debates presided over the decimation of the department’s informational infrastructures, a dynamic that, in an ironic twist, would derail a privatization initiative when it finally arrived. While the two-decade arc of debate over the benefits and pitfalls of privatization concluded with Mumbai’s water infrastructures squarely in the public domain, market logic unmapped Mumbai’s water distribution network.