Progress in sustainable water resources development involves several and diverse disciplines and abilities, including ecologists, economists, sociologists, representatives of the public and private sectors and citizens groups, politicians, and others. Environmental engineers are essential co-participants in this multidisciplinary array, providing scientific and technological expertise that is essential in arriving at sustainable solutions. This theme is illustrated ‘a long the riverrun’ with four cases: cholera, chlorides, cryptosporidiosis and crabs.