“A modular approach to urban water system design increases the number of possible configurations from a given set of inputs (Complex Adaptive Systems). . . .. . . . a diverse repertoire of alternative options for urban water systems, which have internal degrees of freedom that optimize their flexibility and sustainability over time.”
(From p 65 Integrated Urban Water Management by Akica Bahri, Technical Committee, Global Water Partnership – see The Global Water Partnership – Integrated Water Resource Management)
“Complex Adaptive Systems”, “internal degrees of freedom” and “flexibility” are all Systems Theory concepts. So the Global Water Partnership directly acknowledges that Systems Theory must be the governing paradigm of Integrated Water Resource management.
In the same way that Newtonian Science defined a new scientific paradigm and created “engineering” as the modality governing interventions in accordance with this paradigm, so Systems Theory defines a new paradigm for interventions with “systems”.
The “engineering” modality operates from a basic set of underlying concepts and principles such as force, power, works, energy, levers and gears, voltage, current, resistors, transformers etc.
Systems Theory has similar common underlying concepts and principles that govern all natural systems such as attractors, requisite variety, emergence, feedback, progressive displacement, etc.
Understanding these concepts gives insight into the processes by which biotic systems become disrupted and also how to go about effectively countering these disruptive processes.
Hence the Global Water Partnership defines Integrated Water Resource Management to exist in the Systems Theory domain.