Green Infrastructure for Sanitation in Settlements in the Global South: A Narrative Review of Socio-Technical Systems

Abstract

In the developing economies of the Global South, a fundamental challenge in the transition of settlements from rural or periurban to urban is increased environmental contamination as a result of poor sanitation and sanitation management. With governments’ limited ability to connect all neighbourhoods to a city’s existing municipal water, sewerage and other services, decentralised approaches using green infrastructure offer potential to address this challenge. In addition, green infrastructure might facilitate a move towards a holistic response to manage the full water cycle. This paper presents a narrative review of green infrastructure projects, involving constructed wetlands or their variants for wastewater treatment, within vulnerable communities in the Global South. It describes the scale and scope of each project, identifies the challenges of implementation, and reflects on their outcomes for different stakeholder groups. The review demonstrates that decentralised sanitation programs using constructed wetlands for wastewater treatment can provide a range of advantages/benefits/services, dependant on the specific sociocultural, political and biogeophysical contexts of each. Issues of governance and sociocultural appropriateness, rather than technical issues, challenged the implementation of green infrastructure for sanitation in these projects. Projects must be a collaboration between the government, nongovernment organisations and the community. Whether the project is organised from top-down or bottom-up, community consultation is essential. Context will determine the role of the community in the consultation process and the type of information required to guide the design, implementation and governance of the system. In every project to provide decentralised sanitation systems, the community must be participants, not simply beneficiaries.

An assessment of technological development and applications of decentralized water reuse: A critical review and conceptual framework

“…socio-economics of the local population obstruct the implementation of sophisticated technologies (Prescott et al, 2021;Putri, 2017). In this situation, the best practice is to adapt a modular onsite system, especially in areas with limited space, with locally available materials, and green infrastructure is a cost-effective option (Prescott et al, 2021;Putri, 2017).…”

“…However, when it comes to decentralized greywater recycling, governance, the fragmented and fragile geography, lack of human resources (locally trained runners for maintenance services are lacking), in addition to the disadvantaged socio‐economics of the local population obstruct the implementation of sophisticated technologies (Prescott et al, 2021; Putri, 2017). In this situation, the best practice is to adapt a modular onsite system, especially in areas with limited space, with locally available materials, and green infrastructure is a cost‐effective option (Prescott et al, 2021; Putri, 2017).…”

“…However, when it comes to decentralized greywater recycling, governance, the fragmented and fragile geography, lack of human resources (locally trained runners for maintenance services are lacking), in addition to the disadvantaged socio‐economics of the local population obstruct the implementation of sophisticated technologies (Prescott et al, 2021; Putri, 2017). In this situation, the best practice is to adapt a modular onsite system, especially in areas with limited space, with locally available materials, and green infrastructure is a cost‐effective option (Prescott et al, 2021; Putri, 2017). Phytoremediation technology using simple constructed wetlands aided with simple sediment and carbon filter are successful examples of decentralized systems adopted in many informal settlements such as Lima (Peru) and Machaki village (Pakistan) (Prescott et al, 2021).…”

“…In this situation, the best practice is to adapt a modular onsite system, especially in areas with limited space, with locally available materials, and green infrastructure is a cost‐effective option (Prescott et al, 2021; Putri, 2017). Phytoremediation technology using simple constructed wetlands aided with simple sediment and carbon filter are successful examples of decentralized systems adopted in many informal settlements such as Lima (Peru) and Machaki village (Pakistan) (Prescott et al, 2021). With a basic water piping infrastructure facility, decentralized greywater recycling could be done to produce water for mobile toilets too (Box 1).…”

Driving Forces for the Spatial Reconstruction of Rural Settlements in Mountainous Areas Based on Structural Equation Models: A Case Study in Western China

“…This study explored the factors that were important in influencing the intention of peasant households relating to the spatial reconstruction of rural settlements and determined the major driving forces. Regarding the measurement method and index selection of previous studies [54,56,65,[67][68][69], and with consideration of the practical situation of the study area, five driving forces were selected. These formed the latent variables to measure household intention (Table 1) and were as follows: (1) External attractions (A1-A5): enough employment opportunities, education opportunities, a high-quality living environment, and good public infrastructure.…”