Governing the Nexus of Water, Energy and Food: The Case of Wastewater Reuse in Agriculture
Achieving the Sustainable Development Goals (SDGs) requires overcoming institutional siloes and harnessing synergies between the management of water, energy and food resources. This paper employs an agent-based modeling approach to critically examine the recent UN-Water directive on SDG target 6.3, which focuses on wastewater reuse. We advocate for an improved understanding of the factors that determine the feasibility and effectiveness of wastewater reuse, while accounting for regional variations and institutional changes.
By applying the Nexus approach, we demonstrate how it is possible to forge concepts of trade-offs and synergies to draw out coupled perspectives of bio-physical and institutional dimensions of water-energy-food interactions. This paper proposes the use of place-based observatories as a mechanism to support the valorization of data and methodological assumptions, which is a prerequisite for the robust monitoring of global goals.
Conventional unidimensional approaches to SDG monitoring have emphasized a disproportionate focus on the behavior of bio-physical resources, the efficiency of ecological systems, statistical analysis of interactions between SDG goals and targets, and case study research that has neither been pilot-tested nor validated through engagement with governance structures and processes. Such approaches can promote institutional siloes in environmental planning and management, potentially undermining the credibility of the global monitoring regime.
In contrast, our proposed Wastewater Reuse Effectiveness Index (WREI) combines bio-physical and institutional components, relying on data valorization, expert opinion, and the coupling of bio-physical and institutional perspectives. This showcases cutting-edge applications of the Nexus approach in managing trade-offs and fostering synergies in environmental planning and management.
Monitoring Sustainable Development Goal (SDG) Target 6.3 on Wastewater Reuse: Method, Data and Applications of Agent-Based Modeling
Wastewater reuse assumes significance from the perspective of examining both the policy orientation of research and the role of feedback loops in governance systems. Approximately 20 million hectares of land is currently under cultivation worldwide using wastewater. When wastewater is better managed, significant economic benefits can be derived in developing countries through reuse for productive purposes like agriculture, kitchen gardens, and poultry rearing.
Some of the direct benefits of wastewater collection and reuse could include double cropping and lower input costs for agriculture. There may also be important economy-wide trade-offs of encouraging freshwater swaps through the use of treated domestic wastewater in agriculture. While these trade-offs could involve enhanced source sustainability of the urban water supply, lower energy pumping costs, and improved food security arising from increased farm incomes, linearity of outcomes cannot be assumed.
Empirically grounded agent-based models can help evaluate whether hypothesized processes are consistent with empirically observed patterns of behavior. In contexts characterized by complex feedback loops between resource use, agricultural productivity, and considerations of distributional equity (for example, favoring well-to-do vs. poor consumers), posing the relevant question can be a major challenge in devising a methodology for monitoring a global goal on wastewater reuse.
Political Economy of Public Decision Making in the Water-Energy-Food Nexus
Integrative modeling of trade-offs that incorporates perspectives from both bio-physical and institutional domains will highlight the role of the political economy in decision-making. Trade-off analysis will reflect the fact that policy and management choices operating at global, national, and local scales are guided by norms, agency, and individual behavior with regards to the allocation of financial and human resources, as well as institutional capacity, which can impact the goal of balancing bio-physical risks with institutional ones.
The systematic use of literature reviews and expert opinion to develop and pilot-test composite indices raises the prospect of a data-light approach to monitoring SDGs. Specifically, what are the merits of relying on extensive survey data compared to composite indices that are amenable to supporting benchmarking and scenario analysis, and can provide the insight needed to inform decision-making and robust monitoring of global goals?
Plotting the hypothetical component-wise scores of the Wastewater Reuse Effectiveness Index (WREI) for different countries/regions helps in understanding the role of governance/institutions in mobilizing public action in the form of finances, technology, and skill sets to support an effective response to challenges posed by the fact that planetary boundaries are being reached. Such an approach to global monitoring can present a clear picture of the constraints various countries face and can serve as a basis for capacity building in support of normative change.
Conclusion: Implications for Global Public Goods Research
This paper has undertaken a critical examination of the recent UN-Water directive on SDG target 6.3 and shown that synergies are required to ensure coordination between UN agencies (on norms and indicators), Member States (on coherence of policy instruments), and consumers (on perceptions of safety and affordability of services) to advance the achievement of the goal of reuse of wastewater.
We have demonstrated how the development, pilot-testing, and validation of the Wastewater Reuse Effectiveness Index (WREI) relied upon data valorization, expert opinion, and the coupling of bio-physical and institutional models of water-energy-food interactions. This showcases cutting-edge applications of the Nexus approach in managing trade-offs and fostering synergies in environmental planning and management.
The WREI offers a refreshingly novel perspective on monitoring SDG target 6.3 by pointing out that effective reuse of wastewater can emerge only when a threshold of bio-physical risk (e.g., for water quality or precipitation) is crossed, backed by governance/institutional resources in the form of financing, trained functionaries, and networks for information sharing within public agencies. This makes the WREI not only effective but also sustainable in the long run, as technologies and policies may not sustain in the absence of good governance, i.e., appropriate institutions and enforcement mechanisms.
Our analysis makes us skeptical about the prospects of global public goods research when it comes to advocating for institutional, as opposed to normative, change. This is because the effect of proposals for reform of budgetary strategies, plans for staff retrenchment, and organizational restructuring on policy outcomes can be multidimensional, recursive, and non-monotonic.
Therefore, we propose two hypotheses that future Nexus research is underway or being proposed to more rigorously test:
Hypothesis 1: Focusing on Norms and Intention of Agents with reference to Resource Reuse & Recovery
– Countries/regions that are successful with effective reuse of wastewater are more likely to be already successful with delivering public services; the quantum of available financing, skills, and technology need not a-priori be a constraint.
Hypothesis 2: Focusing on Observatories as Mechanisms for Knowledge Translation with reference to Wastewater Reuse in Agriculture
– Countries/regions that do not pursue effective reuse of wastewater in agriculture despite compelling environmental pressures in the form of, for example, water scarcity or declining water quality may benefit from impact evaluations that support the development and pilot-testing of policy instruments (guidelines, notifications, standards, circulars, and directives) with the potential to aid uptake of technical options based on a robust typology of wastewater management and integrative Nexus thresholds to public action.
This hypothesis and theory article is the culmination of 6 years of multi-country and trans-disciplinary collaboration on the Water-Energy-Food (WEF) Nexus. The corresponding author acknowledges the support of various partners in developing some of the ideas contained in this paper.
