Environmental Engineering Reference
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the technological wonder of water supply and sanitary sewers and also
because these networks were and continue to be an amalgam of human
and natural, built and unbuilt. Rather than a wholly new network of
technical components, drainage networks consist of a jumble of natural
and technical elements (ditches, existing waterways, natural depressions,
streets, rooftops, downspouts, and so on) that defy tidy description. Fur-
thermore, drainage networks do not fi t nicely in the Promethean timeline
because they are a premodern form of infrastructure that preceded the
nineteenth-century water supply and wastewater networks. As early as
3000 BC, human settlements had extensive drainage networks to con-
vey rainwater away from buildings and streets. The celebrated Roman
Empire, best known for its aqueducts and roads, had equally impressive
drainage networks that were central to its success. 23 These practices were
largely abandoned after the fall of the Empire and urban drainage strate-
gies tended to be informal and piecemeal with ditches or gutters made of
wood or stone to convey urban runoff to the nearest waterway until the
mid-nineteenth century. With the advent of the engineering profession as
well as the technical and administrative means to design and construct
complex service networks, underground storm drains gradually emerged
as the standard method to convey urban runoff in North America and
Northern Europe. 24
The contemporary distinction between the three urban water networks
refl ected in engineering education as well as construction and administra-
tion activities belies a messier history of development during the nineteenth
century. Illicit dumping of sanitary wastes in surface drainage networks
caused widespread public health and aesthetic problems. Furthermore,
the introduction of consistent water supplies and the adoption of water-
hungry plumbing fi xtures (particularly the water closet) caused a break-
down in existing sanitary systems. Pits for the collection of human waste
were overwhelmed with the rapid increase in wastewater volumes, result-
ing in widespread public health issues. In short, there was no systems view
of urban water in the nineteenth century; water supply and sewerage were
treated as separate operations throughout the century, while the increasing
density of urban populations and the increasing consumption of water
and generation of wastewater volumes created complex linkages between
urban residents and water fl ows. 25
In the 1850s, U.S. cities began to adopt water-carriage systems for
sanitary wastes, transforming waste disposal from a local, labor-intensive
effort into a capital-intensive but convenient method for urban residents to
maintain more healthy urban conditions. 26 The adoption of water-carriage
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