<P> The Romans constructed numerous aqueducts throughout the Empire to bring water into cities and towns--often from distant sources . The water supplied public baths, latrines, fountains, and private households . Aqueducts also provided water for mining operations, milling, farms, and gardens . </P> <P> Aqueducts moved water through gravity alone, usually along a slight overall downward gradient within conduits of stone, brick or concrete, but sometimes through steeper gradients . 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 . The run - off water from aqueducts sometimes drove urban water - mills, and scoured the drains and sewers . </P>

What did the ancient romans build to maintain the supply of water in their cities