The latest edition of this bestselling work continues to offer a state-of-the-art look at modern water management. It emphasizes the application of scientific methods to problems associated with the development, movement, and treatment of water and wastewater. Recognizing that all waters are potential sources of supply, the book's tradition of presenting treatment processes in context of what they can do, rather than in the context of water or wastewater treatment, is becoming more appropriate a s the concept of total water management gains greater acceptance.The sixth edition has been improved with new material added on the EPANET model for analyzing water distribution systems, the processing of sludges, and water reuse. The existing coverage of water use, population projections, urban hydrology, storm drainage system design, and treatment processes has been substantially revised to reflect the latest technologies, engineering practices, and regulations. The authors have included a number of new examples and problems based on actual engineering designs and operations. Computer-oriented solutions are stressed where appropriate. The presentation has been clarified where necessary to make this a valuable text and reference for the civil and environmental engineering student.