Design and evaluate community-based urban rainwater harvesting systems

Thesis Abstract

Urban areas face increasing challenges related to water scarcity, stormwater management, and sustainable resource utilization, necessitating innovative solutions such as community-based rainwater harvesting systems. This study aims to design, implement, and evaluate a comprehensive community-driven model for urban rainwater harvesting to improve water security and mitigate urban flooding. The specific objectives include assessing current rainwater harvesting practices within selected urban communities, designing an optimized rainwater harvesting system tailored to local environmental and socio-economic conditions, and evaluating the technical, socio-behavioral, and economic performance of the proposed system over a twelve-month period. The research adopts a mixed-methods approach, combining qualitative and quantitative techniques to generate a holistic understanding of community-based rainwater systems. The study population comprises residents of three urban neighborhoods in a mid-sized city, with a total population estimated at 15,000 individuals. A stratified random sampling technique was employed to select 300 households for quantitative surveys, ensuring representation across socio-economic strata, while focus group discussions and key informant interviews involving 30 community leaders and local officials provided qualitative insights. Data collection instruments include structured questionnaires, participatory mapping tools, semi-structured interview guides, and observation checklists. The quantitative data will be analyzed using descriptive statistics, chi-square tests, and multivariate regression analysis to identify determinants of system adoption, effectiveness, and sustainability. The qualitative data will be subjected to thematic content analysis using NVivo software, facilitating an exploration of community perceptions, barriers, and motivators. The design phase involves employing sustainable rainwater harvesting principles aligned with the Stormwater Management Model (SWMM) and incorporating community feedback to optimize system functionality. Implementation follows a participatory approach, engaging local residents in installation, maintenance, and educational activities. The evaluation component assesses system performance through parameters such as water volume captured, quality, cost-effectiveness, user satisfaction, and environmental impact, monitored periodically over the year. A cost-benefit analysis and economic feasibility assessment, utilizing net present value (NPV) and payback period calculations, determine financial viability, while social acceptance is gauged through Likert-scale surveys and thematic discussions. Expected findings include significant improvements in household water availability, increased community engagement, and enhanced awareness of sustainable water practices. Data analysis is anticipated to reveal strong correlations between community participation levels and system sustainability, with regression models indicating socio-economic factors influencing adoption rates. The evaluation is expected to demonstrate that well-designed, community-managed rainwater harvesting systems can significantly reduce dependence on municipal supply, lower stormwater runoff volumes, and foster resilience to climate variability. This research contributes to existing knowledge by providing an empirically validated model for community-based urban rainwater harvesting, integrating technical, social, and economic perspectives to inform policy and practice. It advances theoretical understanding through the application of the Diffusion of Innovations Theory and the Social Capital Theory in promoting sustainable water management behaviors. Methodologically, it offers a replicable framework for pilot intervention studies in urban environments. The study concludes that participatory design and strong community engagement are critical drivers of system success and sustainability. Recommendations include scaling up community-led rainwater harvesting initiatives, integrating them into urban water management policies, and developing capacity-building programs to ensure long-term functionality and replicability. Suggestions for further research emphasize exploring technological innovations in rainwater collection and treatment tailored to diverse urban contexts.