The Central United States experienced record-setting flooding during 2011, with floods that extended from headwater streams in the Rocky Mountains, to transboundary rivers in the upper Midwest and Northern Plains, to the deep and wide sand-bedded lower Mississippi River. The U.S. Geological Survey (USGS), as part of its mission, collected extensive information during and in the aftermath of the 2011 floods to support scientific analysis of the origins and consequences of extreme floods. The information collected for the 2011 floods, combined with decades of past data, enables scientists and engineers from the USGS to provide syntheses and scientific analyses to inform emergency managers, planners, and policy makers about life-safety, economic, and environmental-health issues surrounding flood hazards for the 2011 floods and future floods like it. USGS data, information, and scientific analyses provide context and understanding of the effect of floods on complex societal issues such as ecosystem and human health, flood-plain management, climate-change adaptation, economic security, and the associated policies enacted for mitigation.
Among the largest societal questions is "How do we balance agricultural, economic, life-safety, and environmental needs in and along our rivers?" To address this issue, many scientific questions have to be answered including the following:
* How do the 2011 weather and flood conditions compare to the past weather and flood conditions and what can we reasonably expect in the future for flood magnitudes?
* What is the “natural” hydrology of these watersheds and how have they been changed?
* How do rivers change during floods and what effects do they have on the natural and built environment: conversely, what effects do the natural and built environments have on rivers and floods?
* Do floods contribute to the transport and fate of contaminants that affect human and ecosystem health?
In an effort to help address these and other questions, USGS Professional Paper 1798 consists of independent but complementary chapters dealing with various scientific aspects of the 2011 floods in the Central United States.