Design of a Water Tower System for Rural Water Supply: A Case Study of an Ecuadorian Village

Abstract

Rural community water supplies often require the construction of a village water tower. Safe tower design requires careful planning and properly selected materials. In remote villages, transport of concrete or steel materials is cost prohibitive, and locally sourced construction materials are required. This paper presents a case study of a remote Ecuadorian village in the Amazon which used locally available hardwood (referred to locally as “Ecuadorian ironwoodâ€) for water tower construction in conjunction with a local aid-organization. Typical samples of the wood were obtained and important structural properties measured. Wood identification was attempted, but matching mechanical properties and optical microscopy imaging to known woods was inconclusive. Using international building codes, an existing tower design was evaluated for principal failure modes. Because the tower was originally designed without verifying the material’s mechanical properties, the tower was found to be far overdesigned. By considering water flow requirements for various village sizes, this paper shows how the overall tower height, material thickness, and overall material quantity can be reduced while still maintaining adequate factors of safety. By reducing the amount of required material, villager effort and time are significantly reduced in harvesting the required wood from the forest. The measurement and design process in this paper could be replicated for other rural development projects which rely on locally available, but possibly imperfectly characterized, materials for engineering projects.