From the colonial era until the beginning of the twentieth century, most water used in Los Angeles was distributed through channels called zanjas, conduits supplying water for irrigation, power, and household use. Anglo-Americans sought an alternative to this network, and protomodern water mains began domestic deliveries in 1864. Mains did not at first displace zanjas; the two systems evolved together, competing to provide water for the conflicting usages of the era-household use, industrial use, and sewage removal. Angelenos managed the conflicts between usages and supply systems with a complex sociotechnical system of distributed agency and distributed competency: they filed nuisance suits, drafted regulation, and made public and private modifications to the infrastructure, tailoring the network for their particular needs. When the mains supplanted the zanjas, the Los Angeles water supply system lost a significant share of its flexibility and Angelenos much of their control over water.