Page 26 - Urban water supply handbook

URBAN WATER INFRASTRUCTURE: A HISTORICAL PERSPECTIVE

URBAN WATER INFRASTRUCTURE 1.25

FIGURE 1.20 Cover to underground drainage system for water channel from the Majestic
Fountain. (Photo by Larry W. Mays and copyright by Larry W. Mays)

water. The Romans built many aqueducts; however, they were not the first to do so.
King Sennacherio built aqueducts, as did both the Phoenicians and the Hellenes. The
Romans and Hellenes needed extensive aqueduct systems for their fountains, baths,
and gardens. They also realized that water transported from springs was better for
their health than river water and did not need to be lifted to street level, as did river
water. Roman aqueducts were built on elevated structures to provide the needed
slope for water flow. Knowledge of pipe making—using bronze, lead, wood, tile,
and concrete—was in its infancy, and the difficulty of making pipes was a hindrance.
Most Roman piping was made of lead, and even the Romans recognized that water
transported by lead pipes was a health hazard.
The water source for a typical water supply system of a Roman city was a
spring or a dug well, usually with a bucket elevator to raise the water. If the well
water was clear, and of sufficient quantity, it was conveyed to the city by aqueduct.
Also, water from several sources was collected in a reservoir, and then conveyed
by aqueduct or pressure conduit to a distributing reservoir (castellum).
Flow in the Roman aqueducts was obtained by gravity. Water flowed through an
enclosed conduit (specus or rivus), which was typically underground, from the source
to a terminus or distribution tank (castellum). Above ground aqueducts were built on
a raised embankment (substructio) or on an arcade or bridge. Settling tanks (piscinae)
were located along the aqueducts to remove sediments and foreign matter. Subsidiary
lines (vamus) were built at some locations along the aqueduct to supply additional
water. Also subsidiary or branch lines (ramus) were used. At distribution points water

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