Community Values and the Long-term Ecological Integrity of Rapidly Urbanizing Watersheds

Until recently, managing water quality in a watershed was widely viewed as a matter of installing (and operating) an infrastructure to deal with pollution from industrial and domestic urban sewage. Data on discharges and pollutant loads from a population equivalent, generated or collected from within a government bureaucracy, were used by professional engineers to specify the level of infrastructure that would be necessary for either a final effluent or a section of river to meet a particular chemical composition. This conceptual, and (eventually) literal, transformation of untreated pollutant fluxes into river water of a specified quality was based on scientific principles developed since the early 1900s. From the 1960s onwards they were implemented in an increasingly systematic manner through the mathematical models, optimisation, and decision-support schemes of applied systems analysis (see, for example, Beck, 1997). For most of the past century, notably following the advent of the profession of sanitary engineering, the general public had essentially no interest in knowing what these scientific principles might be (Beder, 1997).