The Water-Soil-Waste Nexus: Making It Work

  • 2018/10/19     Dresden, Germany

    By Cornel Dick, Communications and Advocacy, and Dr Tamara Avellán and Mario Roidt, Water Resources Management

    Dealing with water-related issues is pivotal to staying on track of the UN 2030 Agenda for Sustainable Development and meeting the Sustainable Development Goals (SDGs) (United Nations 2018). Water is critical to life and demand for it is increasing from various users. Its quality and quantity depend not only on how water  as a resource  is managed but also how other resources such as waste and soil are handled.

    This calls for the need to move beyond single resource management approaches.


    Established integrated approaches of resource management, though, focus on the one central dimension of the resource system analysed (e.g., Integrated Solid Waste Management assesses solid waste flows within municipal/administrative boundaries). In order to meet the necessity of integrating traditionally separately managed resources and sectors, we need appropriate research frameworks which can grasp the complexity of resource flows across those traditionally drawn borderlines and render it still measurable.

    The Water-Energy-Food Nexus tackles this issue by linking together different sectors (Avellán et al. 2017). The Water-Soil-Waste (WSW) Nexus further strives to analyse the interdependencies not within sectors but of the observed resources in a given environmental system. But environmental systems are complex and could be assessed at varying geographical scales. The results from the analysis would then differ and make action on the ground impossible. For instance, impacts of wastewater can be assessed at the level of a treatment facility, or that of the municipality that produces it, or that of the river basin they lie in. Solutions to reduce the consequences of the impacts would differ significantly for either of those scales.

    In the article “Making the Water–Soil–Waste Nexus Work: Framing the Boundaries of Resource Flows” – published in the journal Sustainability – Avellán et al. (2017) deliver a research framework for the case-oriented application of the WSW Nexus and apply it on two cases: the Mezquital Valley close to Mexico City and the Mourcheh Kourth Industrial Park in Iran.

    Adhering to systems analysis and drawing from already established integrated resource management approaches, Avellán et al. (2017) aim at defining the boundaries of the WSW system, thereby focusing on biophysical processes around the observed resources.

    As the authors point out, one has to keep in mind that the WSW Nexus and the WSW system are (indeed) not just two ways of expressing the same thing – and that it is necessary to distinctly draw the boundaries of the latter to be able to apply the former.

    Avellán et al. (2017) are therefore suggesting a standard but flexible way of how to draw boundaries of the system to successfully analyse the resource fluxes.

    The problem is that the Water-Soil-Waste Nexus is so far lacking a clear methodology and operationalisation for hands-on implementation.


    So, the question is: which elements are necessary to make the WSW Nexus applicable to actual cases? Avellán et al. (2017) assess the system boundaries of already existing integrated resource management approaches (such as Integrated Water Resources Management, Integrated Natural Resources Management, Integrated Solid Waste Management, and the WEF Nexus) and then draw ‘lessons’ from these.

    Avellán et al. (2017) define the boundary of systems analysis under the WSW Nexus as “the geographic area where at least two systems overlap and thus form the WSW Nexus system”. In order to analyse the WSW Nexus the chosen scale must not be too small, i.e. reduced to one municipality or treatment facility, for example. But it must not be too broad either, which means that the analysis should be conducted ‘within the smallest common geographic area of the physical interlinkages of the three resources’ (Avellán et al. 2017).

    Research that develops such frameworks is pivotal to enabling effective action for the 2030 Agenda. Science not only provides the needed information through data collection, but also shows ways and strategies of implementation and allows for evidence-based decision making to achieve the SDGs.


    Avellán, Tamara, Roidt, Mario, Emmer, Adam, von Koerber, Janis, Schneider, Petra and Raber, Wolf. 2017. “Making the Water–Soil–Waste Nexus Work: Framing the Boundaries of Resource Flows.” Sustainability, 9(10):1–17.

    United Nations. 2018. “Sustainable Development Goal 6 Synthesis Report 2018 on Water and Sanitation.” New York.