page_title: Roman aqueduct
section_title: Inspection and maintenance
hierarchical_section_title: Roman aqueduct / Planning, surveying and construction / Inspection and maintenance
caption_attribution_description: English: Nîmes - Castellum Polski: Nîmes - Castellum Latina: Nemausus - Castellum
context_page_description: The Romans constructed aqueducts throughout their Republic and later Empire, to bring water from outside sources into cities and towns. Aqueduct water supplied public baths, latrines, fountains, and private households; it also supported mining operations, milling, farms, and gardens.
  Aqueducts moved water through gravity alone, along a slight overall downward gradient within conduits of stone, brick, or concrete; the steeper the gradient, the faster the flow. Most conduits were buried beneath the ground and followed the contours of the terrain; obstructing peaks were circumvented or, less often, tunneled through. Where valleys or lowlands intervened, the conduit was carried on bridgework, or its contents fed into high-pressure lead, ceramic, or stone pipes and siphoned across. Most aqueduct systems included sedimentation tanks, which helped to reduce any water-borne debris. Sluices and castella aquae regulated the supply to individual destinations. In cities and towns, the run-off water from aqueducts scoured the drains and sewers.
  Rome's first aqueduct was built in 312 BC, and supplied a water fountain at the city's cattle market.
context_section_description: Roman aqueducts required a comprehensive system of regular maintenance. The "clear corridors" created to protect the fabric of underground and overground conduits were regularly patrolled for unlawful ploughing, planting, roadways and buildings. In De aquaeductu, Frontinus describes the penetration of conduits by tree-roots as particularly damaging. The aqueducts conduits would have been regularly inspected and maintained by working patrols, to reduce algal fouling, repair accidental breaches, to clear the conduits of gravel and other loose debris, and to remove channel-narrowing accretions of calcium carbonate in systems fed by hard water sources. Inspection and access points were provided at regular intervals on the standard, buried conduits. Accretions within syphons could drastically reduce flow rates, due to the already narrow diameter of their pipes. Some had sealed openings that might have been used as rodding eyes, possibly using a pull-through device. In Rome, where a hard-water supply was the norm, main pipework was shallowly buried beneath road kerbs, for ease of access; the accumulation of calcium carbonate in these pipes would have necessitated their frequent replacement.
  The aqueducts were under the overall care and governance of a water commissioner (curator aquarum). It was a high status, high-profile appointment. In 97, Frontinus served both as consul and as curator aquarum, under the emperor Nerva. Little is known of the day-to-day business of aqueduct maintenance teams (aquarii). Under the emperor Claudius, Rome's contingent of imperial aquarii comprised a familia aquarum of 700 people both slave and free, funded through a combination of Imperial largesse and water taxes. They were supervised by an Imperial freedman, who held office as procurator aquarium. Theirs was probably a never-ending routine of patrol, inspection and cleaning, punctuated by occasional emergencies. Full closure of any aqueduct for servicing would have been a rare event, kept as brief as possible, with repairs preferably made when water demand was lowest, which was presumably at night. The water supply could be shut off at its aqueduct outlet when small or local repairs were needed, but substantial maintenance and repairs to the aqueduct conduit itself required the complete diversion of water at any point upstream or at the spring-head itself.
caption: Urban distribution tank at Nîmes, France. Circular section pipes radiate from a central reservoir, fed by a square-sectioned aqueduct.
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