As the title indicates, this book deals with hydrology, which is the science of water, and watershed management, which is the process of guiding and organizing land and other resource use on a topographically delineated area drained by a stream system to provide desired goods and services without adversely affecting soil and water resources. The book's contents have been divided into four parts. Part I deals with hydrologic processes and land use. Individual chapters cover precipitation and interception; evapotranspiration and soil water storage; infiltration, runoff, and streamflow; and groundwater. This structure provides a basic introduction to components of the hydrologic cycle.