This paper concerns the water imagery of two iconic passages of Roman satire: Horace's figuration of Lucilius as a river churning with mud at Sat. 1.4.11, and the transformation of that image at Juvenal, Sat. 3.62–8 (the Orontes flowing into the Tiber). It posits new ways of reckoning with the codifications and further potentials of these images by establishing points of contact with the workings of water in the Roman world. The main point of reference will be to the work of Rome's censors, who were charged not only with protecting the moral health of the state, but with ensuring the purity and abundance of the city's water supply as well.