Multi-Criteria Evaluation and Sensitivity Analysis for the Optimal Location of Constructed Wetlands (METland) at Oceanic and Mediterranean Areas

Abstract

METland is a new variety of Constructed Wetland (CW) for treating wastewater where gravel is replaced by a biocompatible electroconductive material to stimulate the metabolism of electroactive bacteria. The system requires a remarkably low land footprint (0.4 m2/pe) compared to conventional CW, due to the high pollutant removal rate exhibited by such microorganisms. In order to predict the optimal locations for METland, a methodology based on Multi-Criteria Evaluation (MCE) techniques applied to Geographical Information Systems (GIS) has been proposed. Seven criteria were evaluated and weighted in the context of Analytical Hierarchy Process (AHP). Finally, a Global Sensitivity Analysis (GSA) was performed using the Sobol method for resource optimization. The model was tested in two locations, oceanic and Mediterranean, to prove its feasibility in different geographical, demographic and climate conditions. The GSA revealed as conclusion the most influential factors in the model: (i) land use, (ii) distance to population centers, and (iii) distance to river beds. Interestingly, the model could predict best suitable locations by reducing the number of analyzed factors to just such three key factors (responsible for 78% of the output variance). The proposed methodology will help decision-making stakeholders in implementing nature-based solutions, including constructed wetlands, for treating wastewater in rural areas.

Knowledge Atlas on the Relationship between Water Management and Constructed Wetlands—A Bibliometric Analysis Based on CiteSpace

“…CFW technology, on the other hand, is less engineered and is easily integrated into existing water environments, such as lakes, ponds, dams, and storage ponds, but it is slightly weaker in terms of the pollutant-removal efficiency [130]. Moreover, CWs are further realised with newer applications, such as bio-electrochemical-assisted constructed wetlands (MET land) [131], green roofs + constructed wetlands [132], and vertical green walls + constructed wetlands [133]. Thus, it is important to flexibly grasp the characteristics of several types of CWs to further explore the deformation of CWs and apply them to urban water management in the future.…”

Assessing METland® Design and Performance Through LCA: Techno-Environmental Study With Multifunctional Unit Perspective

“…Regarding innovative designs, the use of the so-called e-sinks devices was proved to effectively control the electron flow inside the EC bed for enhancing removal rates of pollutants (Prado et al, 2020). Prediction tools for finding suitable locations to implement METland R have been recently developed through a methodology based on Multi-Criteria Evaluation (MCE) techniques and Geographical Information Systems (GIS) (Peñacoba-Antona et al, 2021). The interest and potential of the solution seems clear but, in the context of a Circular Economy transition, the potential environmental impact of a new technology like METland R should be evaluated to prevent impacts from the design (EEA, 2019).…”

Microbial Electrochemically Assisted Treatment Wetlands: Current Flow Density as a Performance Indicator in Real-Scale Systems in Mediterranean and Northern European Locations

“…The results from the four different systems, together with the data from previous laboratory and mesocosms could set the bases for determining design parameters. Furthermore, it has demonstrated the viability of the technology, treating waters under different climatic conditions, water characteristics, and geographical locations ( Peñacoba-Antona et al, 2021a ).…”