Fresh water distribution problematic in Nouakchott

Abstract

Because of its geographical location, Mauritania is characterized by an arid climate. The water resources are thus limited. The annual average rainfall calculated by M.Yeslem [1] over a 60-years period (1931-1991) is 112 mm. Nouakchott, the Mauritanian capital, knew an exceptional growth of the population, carrying it to more than 700 000 inhabitants in the year 2005 [2]. These brisk demographic trends generated a fast expansion of occupied space and a strong pressure on the social equipments and basic infrastructures and in particular for drinking water. Balloffet E.[3] and Seureca A.[4] indicate that the needs of the population of Nouakchott for drinking water, supplied from underground lake of Idini, increased exponentially the last years, in spite of the fragility of the system for which overexploitation could be prejudicial with the resources. This situation was accentuated by the lack of planning and of a framework of urban regulation. In these particular circumstances, the inhabitants of the town of Nouakchott suffer from all problems related to Water resource availability and quality. This study, carried out over a representative sample of Nouakchott's population coming from two poor districts and a rich one, shows that the rate of access to distribution network, to the sanitation network and accessibility to water are very low for the two poor districts of El Mina and Sebkha. 22%, 4% and 35% of the population had access to the above networks. These meduim rates, are due to households in the district of Tevragh-Zeina (a rich area). In addition, this work shows that the vulnerability of the distributed water is big because of the non generalization of the supplying network. In fact, the results of our physico-chemical and bacteriological analyses/tests carried out on site, in different points of the distribution channel, show that the physico-chemical characteristics of the water conform to the World Health Organization (WHO)'s norms. However, the terminal fountains were found to be contaminated with total and fecal coliforms. This work, based on laboratory diagnosis and analyses results, can be an important prerequisite for the installation of an environment and public health management system associated with the quality of the distributed water in Nouakchott.