The Clean Water Act (CWA) requires that wetlands be protected from degradation because of their important ecological functions including maintenance of high water quality and provision of fish and wildlife habitat. However, this protection generally does not encompass riparian areasâ€"the lands bordering rivers and lakesâ€"even though they often provide the same functions as wetlands. Growing recognition of the similarities in wetland and riparian area functioning and the differences in their legal protection led the NRC in 1999 to undertake a study of riparian areas, which has culminated in Riparian Areas: Functioning and Strategies for Management. The report is intended to heighten awareness of riparian areas commensurate with their ecological and societal values. The primary conclusion is that, because riparian areas perform a disproportionate number of biological and physical functions on a unit area basis, restoration of riparian functions along America's waterbodies should be a national goal.

In 1997, New York City adopted a mammoth watershed agreement to protect its drinking water and avoid filtration of its large upstate surface water supply. Shortly thereafter, the NRC began an analysis of the agreement's scientific validity. The resulting book finds New York City's watershed agreement to be a good template for proactive watershed management that, if properly implemented, will maintain high water quality. However, it cautions that the agreement is not a guarantee of permanent filtration avoidance because of changing regulations, uncertainties regarding pollution sources, advances in treatment technologies, and natural variations in watershed conditions. The book recommends that New York City place its highest priority on pathogenic microorganisms in the watershed and direct its resources toward improving methods for detecting pathogens, understanding pathogen transport and fate, and demonstrating that best management practices will remove pathogens. Other recommendations, which are broadly applicable to surface water supplies across the country, target buffer zones, stormwater management, water quality monitoring, and effluent trading.

This fully revised edition provides a modern overview of the intersection of hydrology, water quality, and water management at the rural-urban interface. The book explores the ecosystem services available in wetlands, natural channels and ponds/lakes. As in the first edition, Part I examines the hydrologic cycle by providing strategies for quantifying each component: rainfall (with NOAH 14), infiltration, evapotranspiration and runoff. Part II examines field and farm scale water quality with an introduction to erosion prediction and water quality. Part III provides a concise examination of water management on the field and farm scale, emphasizing channel design, field control structures, measurement structures, groundwater processes and irrigation principles. Part IV then concludes the text with a treatment of basin-scale processes. A comprehensive suite of software tools is available for download, consisting of Excel spreadsheets, with some public domain models such as HY-8 culvert design, and software with public domain readers such as Mathematica, Maple and TK solver.