City Blueprints: Baseline Assessments of Sustainable Water Management in 11 Cities of the Future

The necessity of Urban Water Cycle Services (UWCS) adapting to future stresses
calls for changes that take sustainability into account. Megatrends (e.g. population growth,
water scarcity, pollution and climate change) pose urgent water challenges in cities. In a
previous paper, a set of indicators, i.e., the City Blueprint has been developed to assess the
sustainability of UWCS (Van Leeuwen et al., Wat Resour Manage 26:2177–2197, 2012). In this
paper this approach has been applied in 9 cities and regions in Europe (Amsterdam, Algarve,
Athens, Bucharest, Hamburg, Reggio Emilia, Rotterdam, Oslo and Cities of Scotland) and in 2
African cities in Angola (Kilamba Kiaxi) and Tanzania (Dar es Salaam). The assessments
showed that cities vary considerably with regard to the sustainability of the UWCS. This is also
captured in the Blue City Index (BCI), the arithmetic mean of 24 indicators comprising the City
Blueprint (Van Leeuwen et al., Wat Resour Manage 26:2177–2197, 2012). Theoretically, the
BCI has a minimum score of 0 and a maximum score of 10. The actual BCIs in the 11 cities
studied varied from 3.31 (Kilamba Kiaxi) to 7.72 (Hamburg). The BCI was positively
correlated with the Gross Domestic Product (GDP) per person, the ambitions of the local
authorities regarding the sustainability of the UWCS, the voluntary participation index (VPI)
and all governance indicators according to the World Bank. The study demonstrated that the
variability in sustainability among the UWCS of cities offers great opportunities for short-term
and long-term improvements, provided that cities share their best practices.