Developing a Technique for Rainwater Collection from Rooftops to Alleviate the Water Shortages in Nyala City, Sudan

Abstract

Water scarcity and access to safe drinking water are pressing global challenges aggravated by climate change. This research addressed the specific case of Nyala City in West Sudan, where water shortages occur during the summer due to declining groundwater levels. The study was aims to develop a comprehensive rainwater harvesting system as a potential solution to alleviate water scarcity in the city. The research objectives involved investigating the social and cultural factors that influence the acceptance and adoption of rainwater collection, designing an efficient sand filtration system to ensure water quality, evaluating the effectiveness of the filtration system in eliminating contaminants and pathogens, and analyzing the economic viability of implementing the proposed system. Data for this study were collected through structured questionnaires and interviews conducted with the local community experiencing water scarcity and the relevant staff of the Water Corporation responsible for water supply. Additionally, rainfall data spanning the period of 2011-2020 were obtained from Climatic Research Units (CRU data) and Nyala Shape file from Data-Interpolating Variational Analysis Geographic Information System (DIVA-GIS). The research findings indicate significant variations in rainfall patterns across different regions of Nyala City. These findings were instrumental in informing the design of the rainwater harvesting system, which incorporates five filtration layers, including coarse sand, charcoal, and gravel, to effectively filter and enhance the quality of collected rainwater. To provide practical insights, two case studies were presented: Elshahid Hamza Basic School and a residential house. These case studies illustrated the layout and components of the rainwater harvesting system, emphasizing the integration of plastic tanks and PVC pipes for efficient collection, storage, and distribution of rainwater. Furthermore, calculations were performed to estimate the annual water harvesting potential for the case study buildings based on the roof area and average rainfall. The economic viability of the proposed rainwater harvesting system was analyzed, taking into account the costs associated with materials, installation, and maintenance.