Socially sustainable WASH integrated spatial model for informal settlement

Ensuring adequate Water, Sanitation, and Hygiene (WASH) services in urban informal settlements, home to a significant portion of the global urban poor, remains a critical challenge. The dense populations, substandard infrastructure, and limited access to essential services in these areas exacerbate public health risks and environmental degradation. Research efforts are increasingly focusing on developing sustainable WASH systems that address both the physical infrastructure and the social needs of these vulnerable communities. The spatial arrangement of WASH infrastructure (water points, sanitation facilities, waste management) directly influences its accessibility, usability, and overall effectiveness. Irregular layouts and dense housing in informal settlements often hinder the placement of WASH facilities in safe and accessible locations for all residents. Studies highlight a misalignment between the design and spatial arrangement of services and the socio-spatial patterns of residents, leading to inequalities in service distribution and longer travel distances for essential WASH access.

The high population density, lack of formal infrastructure, and insecure land tenure further complicate WASH service provision in these settlements. Socio-spatial approaches emphasize integrating not only the physical location of services but also the social practices, behaviors, and cultural norms that shape residents’ engagement with WASH infrastructure. This underscores the need for improved spatial planning that considers these factors to enhance the living conditions and quality of life in these areas. Research emphasizes the importance of designing services that align with community preferences, including cultural, gender, and safety considerations. While technical advancements in WASH infrastructure are important, overlooking socio-cultural aspects can limit the effectiveness and long-term use of these facilities. Engaging communities in the design process has been shown to increase satisfaction and promote sustainability.

This proposed research builds upon these advancements by integrating spatial analysis with user preference evaluation to develop a conceptual framework for a socially sustainable WASH model. It aims to evaluate both the spatial efficiency and user satisfaction with existing WASH systems, bridging the gap between technical and social sustainability. Current literature highlights the necessity of considering socio-spatial factors in WASH planning and implementation in informal settlements. However, research on spatial models that prioritize social sustainability, including user preferences and satisfaction, remains limited. This research aims to address this gap by developing a socially sustainable WASH integrated spatial model that optimizes the placement and design of WASH services in informal settlements while ensuring community acceptance and effective use. The focus is on creating WASH systems that are not only functional but also aligned with the specific needs and preferences of the community.

The rationale for this research is particularly relevant to Khulna, the second-largest division in Bangladesh, which faces significant WASH challenges in its informal settlements, home to over 130,000 people. The unplanned layouts of these settlements complicate the effective placement of WASH facilities, forcing residents, especially women and children, to travel long distances for basic services, increasing overcrowding and the risk of waterborne diseases. Cultural norms and gender roles further influence the use of WASH services, with women often avoiding communal toilets due to safety and privacy concerns. A socio-spatial model is crucial for combining the physical layout of facilities with the social practices of the community, allowing for the design of technically viable, culturally acceptable, and socially relevant solutions. This research aims to create a tailored socio-spatial WASH integrated model for Khulna’s informal settlements, assessing socio-spatial characteristics and improving their arrangement based on user satisfaction. The expected outcomes include better living conditions, improved access to WASH services, and an enhanced overall quality of life for residents. By providing a robust framework for government agencies and NGOs, this research seeks to enhance their impact in these vulnerable urban areas.

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The primary and most significant anticipated result of this research is the Development of a Conceptual Socio-Spatial Model for Socially Sustainable Water, Sanitation, and Hygiene (WASH) Systems in Urban Informal Settlements, Informed by Empirical Data and Tailored to the Specific Context of Khulna, Bangladesh. This key outcome is characterized by the following critical achievements:

  • Identification and Mapping of Socio-Spatial WASH Indicators: The research will identify and spatially map key WASH indicators within selected informal settlements in Khulna, revealing spatial disparities in access.
  • Evaluation of User Preferences and Satisfaction: Through the development and application of a Resident Satisfaction Index (RSI) and a Resident Preference Index (RPI), the study will comprehensively evaluate user preferences and satisfaction levels concerning the socio-spatial configuration of WASH indicators.
  • Quantified Relationship Between Quality and Satisfaction: The research will statistically quantify the relationship between the quality of preferred socio-spatial WASH indicators and overall user satisfaction, identifying critical gaps in service delivery.
  • Formulated Conceptual Spatial Model: Based on the analysis of spatial data and user feedback, a conceptual spatial model for a socially sustainable WASH system will be formulated. This model will provide recommendations for optimizing the placement and design of WASH infrastructure to better align with community needs and preferences.
  • Evidence-Based Framework for Intervention: The research will provide an evidence-based framework for government agencies, NGOs, and urban planners to develop and implement more effective and socially sustainable WASH interventions in informal settlements.
  • Enhanced Understanding of Socio-Spatial Dynamics: The study will contribute to a deeper understanding of the complex interplay between spatial arrangements and social practices in shaping the accessibility, usability, and satisfaction with WASH services in underserved urban communities.

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