Hydrologie : recherche actuelle

Assessment of Rainwater Harvesting Potential for Non-Potable Use: A Case Study in Debre Tabor University, Ethiopia

Abstract

Tesfa Gebrie Andualem, Yonas Gebresilasie Hagos and Afera Halefom Teka

Freshwater is expected to become increasingly scarce as temperature and sea levels rise due to Global Climate Change. Water reuse and conservation at different levels is so essential to meet the current water demands. One of the best ways to conserve water at a university level is installing small scale rainwater harvesting system for the demands of the shower, laundry, plant growth, and construction requirement within the campus. The purpose of this study was to determine the rainwater harvesting potential and analyze the significance of a rainwater harvesting system for non-potable use in the university and urban areas. The evaluation of rainwater harvesting was done through surveying and analysis of roof catchment, channel networks, and rainfall data. The evaluation of rainwater potential was followed by the design and characterization of the rainwater harvesting system components. The investment required for rainwater harvesting in the campus was very small since it only requires the construction of storage tank, treatment of water by providing sedimentation tank, alum, and chlorination, and pump cost for lifting  the water from the final treatment tank to the distribution system. The results of this study indicated that installing a rainwater harvesting system is economical to address the water scarcity problem in the university. In Debre Tabor University, the available water to be collected from 13 dormitory buildings and the open surface area was 10372.35 m3, 24,671.43 m3, 41510.99 m3 values of minimum, the average and maximum volume of water respectively. This revealed that there is a huge amount of water which is sufficient enough to meet the demand for non-potable uses. Hence, as climate change continues to threaten parts of the world; individuals and organizations must take micro steps to overcome the effect of climate change on water scarcity. Therefore, the adoption of rainwater harvesting technologies in the university will play a great role in reducing water scarcity and making a conducive environment.