<P> The Romans constructed aqueducts throughout their 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 . </P> <P> 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 reduce any water - borne debris . Sluices and castella aquae (distribution tanks) regulated the supply to individual destinations . In cities and towns, the run - off water from aqueducts scoured the drains and sewers . </P>

A roman engineering device used to carry water over long distances is called an