Water Quality and Aquatic Ecosystem Assessment Using Water Quality Indices in West Africa: Challenge and Perspectives

“Water quality is health” as it is said, “water is life.” The water quality and aquatic ecosystem health assessment is essential for early detection of water habitat degradation and overall aquatic ecosystem disturbances. All water management programs/agencies need simple and cheaper tools for water quality assessment. However, in West Africa there is an urgent need of water quality assessment tools, as far they are very limited. This chapter presents water quality indices as simple and cost-effective tool to monitor water quality. We explore the categories of water quality indices (WQIs), their use/application, and their scope in West African countries. We found that some multimetric indices (MMIs) are developed in West Africa, but they are not well known/used by local water managers and decision makers. There are not yet biotic indices (BIs) and physicochemical water quality indices (PCQWIs) typical to Western African countries areas, but most of them are applied/adapted to meet the needs of West African water quality and ecosystem health assessment. In this chapter, we present the results of some studies led in some West African countries regarding water quality indices (MMIs, BIs, PCWQIs), and address challenges and perspectives for long-term management of water and biological resources in developing countries.