tween fluvial and ecological processes and patterns at multiple scales—an interdisciplinary scientific enterprise. Unlike other emerging sciences, the spatial and temporal boundaries of river science problems are defined by the characteristic spatial and temporal scales of the problem, from local and short-term, to national and long-term. Because of the complexity of rivers, an interdisciplinary, process-based, multiscale approach to studying rivers is needed to support policy-relevant decision making for the nation.

Among federal agencies, the USGS is well poised to be a leader in river science. It historically has provided impartial policy-relevant data to the nation, leading all federal agencies in collecting hydraulic data on rivers, monitoring river conditions, and mapping the nation’s mineral and water resources. It has an established data distribution infrastructure to provide quality data to the nation, multiple disciplines, and an organizational structure that engages in research at local to national scales. The USGS has a clearly well-defined responsibility to assist society in addressing science issues associated with rivers, and provide policy-relevant and policy-neutral information and understanding. Finally, river science spans traditional core scientific disciplines of the USGS—hydrology and hydraulics, sediment transport, biology and ecology, aquatic chemistry, geology, and resource mapping. As such, the USGS is uniquely positioned among federal agencies to draw from the disciplinary expertise throughout its organization to provide needed integration and synthesis.

Thus, the overall design principle for a USGS river science initiative should be to deliver objective policy-relevant science information in critical areas where the nation’s gaps in understanding intersect with the USGS’s strengths and missions. Other recommendations in this report may be viewed respectively as scientific, monitoring, data management, and institutional design principles.