Small Scale Rainwater Harvesting Design for External Usage

Abstract

Water is a life-sustaining resource for humans and all other creatures. Humans, animals, and plants all need water to survive. A proper rainwater harvesting system (RWH) could produce clean and efficient water resources. This study aims to identify outdoor water consumption in UTHM main campus, to choose the appropriate capacity for RWH tank, and to suggest a rainwater harvesting design for outdoor water consumption in UTHM’s main campus. This study involved fieldwork, literature study, collection of rainfall data, simulations using Tangki NAHRIM software, and a semi-structured interview with UTHM’s assistant engineer. The results of this study identified a few outdoor water consumption in the UTHM’s main campus, namely vehicle cleaning and watering the garden. Based on the rainfall data and the catchment area, the average daily harvested rainwater for a week is 2286.3ℓ. Therefore, a water tank system with capacity of 3000ℓ has been proposed as a solution. The results demonstrated two possible RWH designs, first, a stainless steel tank with a capacity of 3000ℓ, second, two polyethene tanks, each with 1500ℓ in capacity. Simulation results from Tangki NAHRIM showed that the proposed RWH system has high storage efficiency up to 97.86%. This research could serve as a guide for future researchers, the Center of Development and Maintenance UTHM (PPP UTHM), and contractors in designing future small-scale rainwater harvesting systems for outdoor water consumption in the UTHM Main Campus.