This new edition of a well-established textbook covers the environmental and engineering aspects of the management of rainwater and wastewater in areas of human development. Urban Drainage deals comprehensively not only with the design of new systems, but also the analysis and upgrading of existing infrastructure. Keeping its balance of principles, practice and research, this new edition has significant new material on modelling, resilience, smart systems, and the global and local context. The two new authors bring further research and practice-based experience. This is an essential text for undergraduate and graduate students, lecturers and researchers in water engineering, environmental engineering, public health engineering, engineering hydrology, and related non-engineering disciplines. It also serves as a dependable reference for drainage engineers in water service providers, local authorities, and for consulting engineers. Extensive examples are used to support and demonstrate the key issues throughout the text.