Introduction

Freshwaters represent less than 3% of the total water present on Earth, rivers and lakes around 0.01%. However these systems are crucial for human well-being. Indeed, they are used as resources for both fisheries and drinking water, and serve as recreational areas. Mid-sized lakes exemplify particularly several key challenges for sustainable freshwater management over the next decades. The ever-increasing population will heighten drinking water demand, but will also exacerbate the release of pollutants to aquatic systems. This is especially true in terms of emerging micropollutants that may affect water quality. The chapter also presents some of the key concepts discussed in this book. The book deals with the agricultural source of micropollutants and the influence of a wastewater treatment plant on a bay. It also deals with the risk assessment of the mixture of the compounds present in lake water. The book illustrates the urban sources of pollutants with pharmaceuticals and biocides.