Impacts of impervious cover, water withdrawals, and climate change on river flows in the conterminous US

Abstract. Rivers are essential to aquatic ecosystem and societal sustainability, but are increasingly impacted by water withdrawals, land-use change, and climate change. The relative and cumulative effects of these stressors on continental river flows are relatively unknown. In this study, we used an integrated water balance and flow routing model to evaluate the impacts of impervious cover and water withdrawal on river flow across the conterminous US at the 8-digit Hydrologic Unit Code (HUC) watershed scale. We then estimated the impacts of projected change in withdrawals, impervious cover, and climate under the B1 "Low" and A2 "High" emission scenarios on river flows by 2060. Our results suggest that compared to no impervious cover, 2010 levels of impervious cover increased river flows by 9.9% on average with larger impacts in and downstream of major metropolitan areas. In contrast, compared to no water withdrawals, 2005 withdrawals decreased river flows by 1.4% on average with larger impacts in heavily irrigated arid regions of Western US. By 2060, impacts of climate change were predicted to overwhelm the potential gain in river flow due to future changes in impervious cover and add to the potential reduction in river flows from withdrawals, decreasing mean annual river flows from 2010 levels by 16% on average. However, increases in impervious cover by 2060 may offset the impact of climate change during the growing season in some watersheds. Large water withdrawals will aggravate the predicted impact of climate change on river flows, particularly in the Western US. Predicted ecohydrological impacts of land cover, water withdrawal, and climate change will likely include alteration of the terrestrial water balance, stream channel habitat, riparian and aquatic community structure in snow-dominated basins, and fish and mussel extirpations in heavily impacted watersheds. These changes may also require new infrastructure to support increasing anthropogenic demand for water, relocation of agricultural production, and/or water conservation measures. Given that the impacts of land use, withdrawals and climate may be either additive or offsetting in different magnitudes, integrated and spatially explicit modeling and management approaches are necessary to effectively manage water resources for aquatic life and human use in the face of global change.

[1]  G. McCabe,et al.  Century‐scale variability in global annual runoff examined using a water balance model , 2011 .

[2]  Robert R. Pierce,et al.  Estimated Use of Water in the United States in 1995 , 1998 .

[3]  Steven L. Markstrom,et al.  A Monthly Water-Balance Model Driven By a Graphical User Interface , 2007 .

[4]  Gregory J. McCabe,et al.  Independent effects of temperature and precipitation on modeled runoff in the conterminous United States , 2011 .

[5]  B. Santer,et al.  Selecting global climate models for regional climate change studies , 2009, Proceedings of the National Academy of Sciences.

[6]  Joshua H. Viers,et al.  Ecology and Management of the Spring Snowmelt Recession , 2009 .

[7]  Howard W. Lull,et al.  Hydrologic effects from urbanization of forested watersheds in the northeast , 1969 .

[8]  M. Simpson.  Global Climate Change Impacts in the United States , 2011 .

[9]  Victor Koren,et al.  Using SSURGO data to improve Sacramento Model a priori parameter estimates , 2006 .

[10]  B. Bates,et al.  Climate Change and Water: Technical Paper VI , 2008 .

[11]  F. P. Kapinos,et al.  Hydrologic unit maps , 1987 .

[12]  Kelly K. Caylor,et al.  Dryland ecohydrology and climate change: critical issues and technical advances , 2012 .

[13]  J. Meyer,et al.  Streams in the Urban Landscape , 2001 .

[14]  Y. Ouyang,et al.  Managing forest water quantity and quality under climate change , 2014 .

[15]  Daren M. Carlisle,et al.  Alteration of streamflow magnitudes and potential ecological consequences: a multiregional assessment , 2011 .

[16]  C. Schneider,et al.  Coextirpation of host–affiliate relationships in rivers: the role of climate change, water withdrawal, and host‐specificity , 2011 .

[17]  V. Koren,et al.  Evaluation of a grid-based distributed hydrological model over a large area , 2006 .

[18]  N. Poff,et al.  Ecological responses to altered flow regimes: a literature review to inform the science and management of environmental flows , 2010 .

[19]  Qingyun Duan,et al.  Use of a Priori Parameter Estimates in the Derivation of Spatially Consistent Parameter Sets of Rainfall‐Runoff Models , 2013 .

[20]  Yan Zhang,et al.  A general predictive model for estimating monthly ecosystem evapotranspiration , 2011 .

[21]  W. Lucht,et al.  Causes of change in 20th century global river discharge , 2008 .

[22]  Alan M. Lumb,et al.  Hydro-Climatic Data Network (HCDN) Streamflow Data Set, 1874-1988 , 1993 .

[23]  R. Stouffer,et al.  Stationarity Is Dead: Whither Water Management? , 2008, Science.

[24]  Hoshin Vijai Gupta,et al.  Toward improved identification of hydrological models: A diagnostic evaluation of the “abcd” monthly water balance model for the conterminous United States , 2010 .

[25]  D. Lodge,et al.  Going with the flow: using species-discharge relationships to forecast losses in fish biodiversity. , 2006, Ecology.

[26]  Philip B. Duffy,et al.  Guidelines for Constructing Climate Scenarios , 2011 .

[27]  N. Arnell.  Climate change and global water resources , 1999 .

[28]  N. LeRoy Poff,et al.  Hydrologic variation with land use across the contiguous United States: Geomorphic and ecological consequences for stream ecosystems , 2006 .

[29]  Christopher A. Barnes,et al.  Completion of the 2006 National Land Cover Database for the conterminous United States. , 2011 .

[30]  G. Jewitt.  Water and Forests , 2006 .

[31]  John F. B. Mitchell,et al.  THE WCRP CMIP3 Multimodel Dataset: A New Era in Climate Change Research , 2007 .

[32]  T. Schueler.  The importance of imperviousness , 1995 .

[33]  Petra Döll,et al.  Global-scale analysis of river flow alterations due to water withdrawals and reservoirs , 2009 .

[34]  Anne Choate,et al.  National housing and impervious surface scenarios for integrated climate impact assessments , 2010, Proceedings of the National Academy of Sciences.

[35]  R. Naiman,et al.  Freshwater biodiversity: importance, threats, status and conservation challenges , 2006, Biological reviews of the Cambridge Philosophical Society.

[36]  W. Graf.  Dam nation: A geographic census of American dams and their large‐scale hydrologic impacts , 1999 .

[37]  G. McCabe,et al.  SPATIAL VARIABILITY IN WATER‐BALANCE MODEL PERFORMANCE IN THE CONTERMINOUS UNITED STATES 1 , 2002 .

[38]  Ge Sun,et al.  Upscaling key ecosystem functions across the conterminous United States by a water‐centric ecosystem model , 2011 .

[39]  R. B. Zelt,et al.  Water-level changes in the High Plains aquifer--predevelopment to 1992 , 1994 .

[40]  P. Döll,et al.  Global estimates of water withdrawals and availability under current and future “business-as-usual” conditions , 2003 .

[41]  B. G. Lockaby,et al.  Water Quantity and Quality at the Urban–Rural Interface , 2012 .

[42]  A. Thomson,et al.  Climate Change Impacts for the Conterminous USA: An Integrated Assessment , 2005 .

[43]  C. Vörösmarty,et al.  Reconstructing 20 th century global hydrography : a contribution to the Global Terrestrial Network-Hydrology ( GTN-H ) , 2010 .

[44]  Mei Zhao,et al.  The impact of land cover change on the atmospheric circulation , 2001 .

[45]  Ge Sun,et al.  Impacts of Multiple Stresses on Water Demand and Supply Across the Southeastern United States 1 , 2008 .

[46]  Alex K. Manda,et al.  Urbanization Effects on Watershed Hydrology and In-Stream Processes in the Southern United States , 2010 .

[47]  C. Daly,et al.  A Statistical-Topographic Model for Mapping Climatological Precipitation over Mountainous Terrain , 1994 .

[48]  R. B. Jackson,et al.  Water in a changing world , 2001 .

[49]  Maosheng Zhao,et al.  Improvements of the MODIS terrestrial gross and net primary production global data set , 2005 .

[50]  U. Shani.  AMERICAN SOCIETY OF AGRONOMY CROP SCIENCE SOCIETY OF AMERICA SOIL SCIENCE SOCIETY OF AMERICA , 2005 .

[51]  P. Ciais,et al.  Changes in climate and land use have a larger direct impact than rising CO2 on global river runoff trends , 2007, Proceedings of the National Academy of Sciences.

[52]  C. Vörösmarty,et al.  Global water resources: vulnerability from climate change and population growth. , 2000, Science.

[53]  A. Robock,et al.  Large-scale water cycle perturbation due to irrigation pumping in the US High Plains: A synthesis of observed streamflow changes , 2010 .

[54]  J. Olden,et al.  Homogenization of regional river dynamics by dams and global biodiversity implications , 2007, Proceedings of the National Academy of Sciences.

[55]  Raghavan Srinivasan,et al.  Climate Change Impacts for the Conterminous USA: An Integrated Assessment , 2005 .

[56]  F. Ludwig,et al.  Impact of reservoirs on river discharge and irrigation water supply during the 20th century , 2011 .

[57]  G. McCabe,et al.  GENERAL‐CIRCULATION‐MODEL SIMULATIONS OF FUTURE SNOWPACK IN THE WESTERN UNITED STATES 1 , 1999 .

[58]  B. Bates,et al.  Climate change and water. , 2008 .

[59]  Sarah Praskievicz,et al.  A review of hydrological modelling of basin-scale climate change and urban development impacts , 2009 .

[60]  Nancy L. Barber,et al.  Estimated use of water in the United States in 2005 , 2009 .

[61]  Vijay P. Singh,et al.  The NWS River Forecast System - catchment modeling. , 1995 .