Three Engineering Paradigms in the Historical Development of Water Services: More, Better and Cheaper Water to European Cities
Résumé
The size and complexity of large cities creates the ‘urban water’ sustainability issue: where water transport and treatment technologies, public water services, including public water supply, sewage collection and treatment, and storm water control, had become the object of specific policies, separate from water resource allocation. Today, large metropolitan areas cannot take natural abundance for granted any more, and they need to protect and to manage water resources, if only to reduce the long term cost of transporting and treating water. In this chapter, we describe the historical development of water services in European metropolitan areas, placing the technological developments in their geographic, socio-economic, and political contexts. Our framework follows the successive contributions of three paradigms: civil engineering, sanitary engineering, and environmental engineering. Civil engineering has to do with the ‘quantity of water’, and it allows water to be moved in and out of cities, up hills, and under floors. Sanitary engineering has to do with ‘water quality’, and water treatment has given cities more freedom to take water from nearby rivers and to reduce impacts of sewer discharge. Lastly, environmental engineering has the potential to overcome supply-side shortcomings: it can use demand-side management, water conservation, water allocation flexibility; it can also provide an integrated approach to water services, water resources management, and land use policies.