Study of Water in a Rainwater Harvesting Technique (Majels and Fesguias) in the Matmata Mountains

Abstract

Located in the South of Tunisia, the mounts of Matmata, face a rarity and large irregularity of water resources. This scarcity has driven the local population to invent techniques like “Mejel” and “Fesguia” to store rainwater in order to cover the needs over a longer period of time. The traditional rainwater harvesting techniques in the Matmata Mountains are essentially characterized by their key role in the storage of runoff water, which represents a significant renewable water potential despite the scarcity of rainfall. Serious attempts to exploit the runoff water for human consumption and rainfed agriculture and reduce the water erosion in the mountain regions. This study aims to examine the rainwater stored in collection tanks (called “Mejel” and “Fesguia”) based on chemical analysis of 327 samples of water, carried out in the Laboratory of Eremology and Combating Desertification at the Arid Regions Institute (ARI) Medenine-Tunisia. The results build an idea about the quality of water tanks intended for human consumption. In fact, the physico-chemical analysis of water in tanks showed an acceptable chemical composition that meets the standard suggested by the WHO except for a few samples. However, the microbiological analysis has shown that 60% of the collected samples have a quality that does not comply with the standards, which is why a disinfection operation is mandatory to prevent or at least minimize any kind of microbial contamination.