As urban areas expand, the need for sustainable water management becomes increasingly urgent. Traditional approaches treat water supply, wastewater and stormwater systems separately, whereas integrated approaches consider the urban water cycle as a whole. Although integrated management is widely advocated, direct quantitative comparisons across different integration perspectives remain limited. This study addresses this gap by applying the urban water use (UWU) decision-support tool to compare three integration levels: Limited, Partial, and Broad, reflecting different managerial perspectives during planning. Results show that Broad Integration outperformed the other approaches, increasing the Effectiveness Index by up to 81% compared to Limited Integration and by up to 21% compared to Partial Integration, depending on the group of measures. By revealing synergies and trade-offs that remain hidden under lower integration levels, the findings support more informed decision-making and reinforce the need to shift from fragmented toward integrated urban water management, particularly in complex urban contexts.
Hoepers et al. (Tue,) studied this question.