In the 3rd century AD, the Roman town began a transformation process with significant consequences in regards to the previous urban organization and construction dynamics. This paper addresses an issue that, among several changes that occurred in the Late Antique town, has been largely overlooked: the mutation of the city sewerage network from the 3rd to the 6th centuries AD. As in this period the ancient sewerage systems were no longer properly maintained as they used to be, certain methods were employed to keep them operational, such as the reuse of some previously abandoned sewers or its rebuilding by using mixed construction techniques or salvaged construction materials. By focusing on some examples from Hispania we intend to outline the last maintenance processes and the final abandon of the urban sewerage systems in the towns of that particular Roman Province.