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• 1. [Article] The fractal structure of surface water waves near breaking

  The goal of this research project is to determine the fractal nature, if any, which certain surface water waves exhibit when viewed on a microscopic scale. We make use of the mathematical formulation of ...

  Citation × Citation Citation Abstract Copy Title: The fractal structure of surface water waves near breaking Author: Munzenmayer, Katja The goal of this research project is to determine the fractal nature, if any, which certain surface water waves exhibit when viewed on a microscopic scale. We make use of the mathematical formulation of non-viscous fluids describing their physical properties. Using these expressions and including boundary conditions for free surfaces as well as taking the surface tension into consideration, we obtain a partial differential equation describing the dynamics of surface water waves. A brief introduction to the study of fractal geometry with several examples of well-known fractals is included. An important property of fractals is their non-integral dimension. Several methods of determining the dimension of a curve are described in this paper. Our wave equation is examined under different assumptions representing the conditions of a surface water wave near its breaking point. Solutions are developed using analytical and numerical methods. We determine the dimension of 'rough' solutions using one of the methods introduced and conclude that under certain conditions, surface water waves near their breaking point exhibit a fractal structure on a microscopic scale. Title: The fractal structure of surface water waves near breaking Author: Munzenmayer, Katja The goal of this research project is to determine the fractal nature, if any, which certain surface water waves exhibit when viewed on a microscopic scale. We make use of the mathematical formulation of non-viscous fluids describing their physical properties. Using these expressions and including boundary conditions for free surfaces as well as taking the surface tension into consideration, we obtain a partial differential equation describing the dynamics of surface water waves. A brief introduction to the study of fractal geometry with several examples of well-known fractals is included. An important property of fractals is their non-integral dimension. Several methods of determining the dimension of a curve are described in this paper. Our wave equation is examined under different assumptions representing the conditions of a surface water wave near its breaking point. Solutions are developed using analytical and numerical methods. We determine the dimension of 'rough' solutions using one of the methods introduced and conclude that under certain conditions, surface water waves near their breaking point exhibit a fractal structure on a microscopic scale. Close

• 2. [Article] Hydrologic connectivity constrains partitioning of global terrestrial water fluxes

  This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in the journal Science on 10 July 2015, ...

  Citation × Citation Citation Abstract Copy Title: Hydrologic connectivity constrains partitioning of global terrestrial water fluxes Author: Noone, David, Bowen, Gabriel, Good, Stephen P. This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in the journal Science on 10 July 2015, Volume 349 number 6244, DOI:10.1126/science.aaa5931. The published article is copyrighted by the American Association for the Advancement of Science and can be found at: http://www.sciencemag.org/journals/ Title: Hydrologic connectivity constrains partitioning of global terrestrial water fluxes Author: Noone, David, Bowen, Gabriel, Good, Stephen P. This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in the journal Science on 10 July 2015, Volume 349 number 6244, DOI:10.1126/science.aaa5931. The published article is copyrighted by the American Association for the Advancement of Science and can be found at: http://www.sciencemag.org/journals/ Close

• 3. [Article] Toxic Pollutants Measured in Surface Water and Fish Collected from the Willamette River Basin by the Oregon Department of Environmental Quality (2008 – 2010)

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Toxic Pollutants Measured in Surface Water and Fish Collected from the Willamette River Basin by the Oregon Department of Environmental Quality (2008 – 2010) Author: Hamel, Allen, Coyle, Jim, Johnson, Ben Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Toxic Pollutants Measured in Surface Water and Fish Collected from the Willamette River Basin by the Oregon Department of Environmental Quality (2008 – 2010) Author: Hamel, Allen, Coyle, Jim, Johnson, Ben Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 4. [Article] Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment, and cultured oysters in the Chesapeake Bay, MD, USA

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersi...

  Citation × Citation Citation Abstract Copy Title: Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment, and cultured oysters in the Chesapeake Bay, MD, USA Author: Jacobs, John M., Shaw, Kristi S., Crump, Byron C. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/microbiology. Title: Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment, and cultured oysters in the Chesapeake Bay, MD, USA Author: Jacobs, John M., Shaw, Kristi S., Crump, Byron C. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/microbiology. Close

• 5. [Article] Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin

  Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on ...

  Citation × Citation Citation Abstract Copy Title: Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin Author: Abdallah, Mohamed (Mohamed Ahmed B.) Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on vegetation and how changes in surface-soil water affect plant water uptake. Studies in arid environments have evaluated the effect of groundwater variation and simulated precipitation on plant production and vegetation condition but it is not clear if plants respond equally to the availability of surface water or groundwater. This study was conducted in a greenhouse to evaluate growth and physiology of three desert graminoids (Distichlis spicata, Leymus triticoides, and Juncus arcticus) as affected by surface water availability (mimicking precipitation) or subsurface water availability (mimicking groundwater). The species of study are amply distributed in wetlands and open rangelands of western USA and were collected from two sources of ecological distribution: an area near Bishop, California, and an area near Burns, Oregon. The Bishop, California area has a characteristic shallow aquifer and plants in this area are considered somewhat dependent on groundwater. The Burns, Oregon, area sustains the same species but in a variety of soil moisture conditions. We had two general hypotheses for this study: 1) that the use of surface water is favored over groundwater and 2) that there are ecotypic differences in the response of the species to water availability. The first hypothesis was partially supported by the results of the study, but variability existed among species. However, when all species had equal access to both surface soil water and groundwater plants tended to preferentially use surface water. The second hypothesis was clearly supported by our results. Although the mechanism is not clear, it is possible that an area with periodic and predictable shallow groundwater underlying a dry or saline soil layer, such as the California site, might favor plant ecotypes with high proficiency in water acquisition by deeper roots. Knowledge of water use characteristics of vegetation is essential to provide management guidelines for areas where plants depend on both surface-soil water and groundwater. This study contributed to that knowledge. Further studies on ecotypic variation and an expansion to different species that inhabit areas with shallow aquifers are recommended. Title: Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin Author: Abdallah, Mohamed (Mohamed Ahmed B.) Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on vegetation and how changes in surface-soil water affect plant water uptake. Studies in arid environments have evaluated the effect of groundwater variation and simulated precipitation on plant production and vegetation condition but it is not clear if plants respond equally to the availability of surface water or groundwater. This study was conducted in a greenhouse to evaluate growth and physiology of three desert graminoids (Distichlis spicata, Leymus triticoides, and Juncus arcticus) as affected by surface water availability (mimicking precipitation) or subsurface water availability (mimicking groundwater). The species of study are amply distributed in wetlands and open rangelands of western USA and were collected from two sources of ecological distribution: an area near Bishop, California, and an area near Burns, Oregon. The Bishop, California area has a characteristic shallow aquifer and plants in this area are considered somewhat dependent on groundwater. The Burns, Oregon, area sustains the same species but in a variety of soil moisture conditions. We had two general hypotheses for this study: 1) that the use of surface water is favored over groundwater and 2) that there are ecotypic differences in the response of the species to water availability. The first hypothesis was partially supported by the results of the study, but variability existed among species. However, when all species had equal access to both surface soil water and groundwater plants tended to preferentially use surface water. The second hypothesis was clearly supported by our results. Although the mechanism is not clear, it is possible that an area with periodic and predictable shallow groundwater underlying a dry or saline soil layer, such as the California site, might favor plant ecotypes with high proficiency in water acquisition by deeper roots. Knowledge of water use characteristics of vegetation is essential to provide management guidelines for areas where plants depend on both surface-soil water and groundwater. This study contributed to that knowledge. Further studies on ecotypic variation and an expansion to different species that inhabit areas with shallow aquifers are recommended. Close

• 6. [Article] Oxygen isotope ratio, barium and salinity in waters around the North American coast from the Pacific to the Atlantic: Implications for freshwater sources to the Arctic throughflow

  In 2002, oxygen isotope ratios of water (H2 18O/H2 16O), dissolved barium, and salinity were measured in surface waters around northern North America to identify freshwater sources and to provide a large-scale ...

  Citation × Citation Citation Abstract Copy Title: Oxygen isotope ratio, barium and salinity in waters around the North American coast from the Pacific to the Atlantic: Implications for freshwater sources to the Arctic throughflow Author: McLaughlin, Fiona A., Carmack, Eddy C., Yamamoto-Kawai, Michiyo, Falkner, Kelly K. In 2002, oxygen isotope ratios of water (H2 18O/H2 16O), dissolved barium, and salinity were measured in surface waters around northern North America to identify freshwater sources and to provide a large-scale background for interpretation of regional inputs and processes. Oxygen isotope ratios showed that precipitation, river runoff, and sea ice meltwater were all significant contributors to the freshwater carried by the coastal component of the Arctic throughflow. Precipitation and runoff contributed 40% and 60%, respectively, to the freshwater found in surface waters along the Pacific coast. Sea ice meltwater contributed up to 65% to waters residing near the Mackenzie River and in the Canadian Arctic Archipelago. The salinity-barium relationship, after being corrected for dilution by sea ice meltwater, indicated that freshwater from the Mackenzie River flowed eastward into Amundsen Gulf. It did not, however, continue eastward through Dolphin Union Strait and Coronation Gulf in 2002. In the eastern part of the Canadian Arctic Archipelago, Baffin Bay and the Labrador Sea, barium concentrations in surface waters were low, the result of biological activity and/or local freshwater inputs with low barium concentrations. Title: Oxygen isotope ratio, barium and salinity in waters around the North American coast from the Pacific to the Atlantic: Implications for freshwater sources to the Arctic throughflow Author: McLaughlin, Fiona A., Carmack, Eddy C., Yamamoto-Kawai, Michiyo, Falkner, Kelly K. In 2002, oxygen isotope ratios of water (H2 18O/H2 16O), dissolved barium, and salinity were measured in surface waters around northern North America to identify freshwater sources and to provide a large-scale background for interpretation of regional inputs and processes. Oxygen isotope ratios showed that precipitation, river runoff, and sea ice meltwater were all significant contributors to the freshwater carried by the coastal component of the Arctic throughflow. Precipitation and runoff contributed 40% and 60%, respectively, to the freshwater found in surface waters along the Pacific coast. Sea ice meltwater contributed up to 65% to waters residing near the Mackenzie River and in the Canadian Arctic Archipelago. The salinity-barium relationship, after being corrected for dilution by sea ice meltwater, indicated that freshwater from the Mackenzie River flowed eastward into Amundsen Gulf. It did not, however, continue eastward through Dolphin Union Strait and Coronation Gulf in 2002. In the eastern part of the Canadian Arctic Archipelago, Baffin Bay and the Labrador Sea, barium concentrations in surface waters were low, the result of biological activity and/or local freshwater inputs with low barium concentrations. Close

• 7. [Article] Sub-regional detention siting : a methodology using GIS

  The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s ...

  Citation × Citation Citation Abstract Copy Title: Sub-regional detention siting : a methodology using GIS Author: Murdock, Carol L. The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s and has recently accelerated. A landscape level analysis of the urbanization process was combined with the results of a recently completed storm water master plan for the area. The project resulted in the identification of potential locations for combined detention and water quality facilities. It also served to further justify the recent revision of surface water management rules and regulations to include requirements for lower release rates from detention facilities and riparian and wetland buffers. Geographic Information Systems (GIS) was used extensively throughout the project to provide data input into the XPSWMM model that was used to analyze storm water flows and to identify infrastructure needs and requirements. In addition, GIS played a pivotal role in identifying factors which may be contributing to changes in stream condition in the basin. The results of this analysis project will be used by surface water managers in their continuing effort to refine current surface water management rules and regulations in the face of on-going development and continued urbanization. Title: Sub-regional detention siting : a methodology using GIS Author: Murdock, Carol L. The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s and has recently accelerated. A landscape level analysis of the urbanization process was combined with the results of a recently completed storm water master plan for the area. The project resulted in the identification of potential locations for combined detention and water quality facilities. It also served to further justify the recent revision of surface water management rules and regulations to include requirements for lower release rates from detention facilities and riparian and wetland buffers. Geographic Information Systems (GIS) was used extensively throughout the project to provide data input into the XPSWMM model that was used to analyze storm water flows and to identify infrastructure needs and requirements. In addition, GIS played a pivotal role in identifying factors which may be contributing to changes in stream condition in the basin. The results of this analysis project will be used by surface water managers in their continuing effort to refine current surface water management rules and regulations in the face of on-going development and continued urbanization. Close

• 8. [Article] The effects of land use on mineral flat wetland hydrologic processes in lowland agricultural catchments

  Hydrologic processes within mineral flat wetlands, along with their connections to groundwater and downstream surface water in lowland agricultural catchments are poorly understood, particularly under ...

  Citation × Citation Citation Abstract Copy Title: The effects of land use on mineral flat wetland hydrologic processes in lowland agricultural catchments Author: Marshall, Sarah M. (Sarah Marie) Hydrologic processes within mineral flat wetlands, along with their connections to groundwater and downstream surface water in lowland agricultural catchments are poorly understood, particularly under different land uses. In the three field studies included in this thesis, we examined infiltration, wetland hydroperiod, groundwater recharge dynamics, surface runoff generation, and water quality in mineral flat wetlands using a combination of soil and hydrometric measurements, stable isotope tracers, and water chemistry analysis. Our overarching objectives were to examine, for mineral flat wetlands under native prairie, farmed grassland, and restored prairie land cover: 1) how different land management influences infiltration and wetland hydroperiod at the plot scale, 2) the effects of land use on seasonal groundwater-surface water dynamics at the field scale, and 3) seasonal variation in runoff sources and nutrient transport from native prairie and farmed wetlands at the small catchment scale. At the plot scale, our results suggest that edaphic factors, particularly those related to soil structure, are strongly associated with wetland infiltration and overall hydroperiod across least-altered prairie, farmed, and restored prairie mineral flat wetlands. The hydroperiod metrics we examined were generally more sensitive to level of site disturbance than land use alone. At the field scale, our results indicate that, in spite of land use differences and slight variations in soil stratigraphy, many similarities exist in overall wetland hydroperiod, water sources and evaporation rates for mineral flat wetlands in the Willamette Valley lowlands. Isotopic evidence suggests that the greatest degree of groundwater-surface water mixing occurs in the upper 0.5 m of the saturated soil profile across sites under all land uses. Finally, at the small catchment scale, farmed wetland runoff was isotopically similar to field surface water for most of the wet season, indicating that saturation excess was an important runoff generation process. Prairie wetland runoff was isotopically similar to upstream water throughout the winter, and briefly similar to shallow groundwater and surface water within the wetland in mid-spring. Throughout the wet season, elevated nitrate, sulfate, and chloride concentrations were observed in groundwater and surface water at the farm site, and deeper groundwater at the prairie site. Upstream-downstream runoff chemistry remained similar throughout the wet season at the prairie site. Farm site runoff chemistry reflected the dominant water source within the farm field throughout the wet season. Our findings suggest that, while surface water pathways dominate runoff from wetland flats under farm land use, large wetland flat fields have a high potential to absorb, store, and process nutrients and agrochemicals from on-site and nearby off-site chemical inputs. Mineral flats that maintain wetland hydrology in spite of farm use represent a unique balance between agricultural production and preservation of some of the water storage and delay, and water quality-related ecosystem services once provided at a much larger scale in the Willamette Valley lowlands. We anticipate that results of this work will lead to better understanding of key site-scale edaphic and hydrologic factors to consider when prioritizing and managing sites for restoration, and how site disturbance under a variety of land uses may impact different hydrologic processes and components of the wetland hydroperiod. Additionally, our results provide a better understanding of how land use affects seasonal runoff generation processes in mineral flat wetlands, and the water quality implications of modifying groundwater and surface water connectivity between mineral flats and surrounding surface drainage networks. Title: The effects of land use on mineral flat wetland hydrologic processes in lowland agricultural catchments Author: Marshall, Sarah M. (Sarah Marie) Hydrologic processes within mineral flat wetlands, along with their connections to groundwater and downstream surface water in lowland agricultural catchments are poorly understood, particularly under different land uses. In the three field studies included in this thesis, we examined infiltration, wetland hydroperiod, groundwater recharge dynamics, surface runoff generation, and water quality in mineral flat wetlands using a combination of soil and hydrometric measurements, stable isotope tracers, and water chemistry analysis. Our overarching objectives were to examine, for mineral flat wetlands under native prairie, farmed grassland, and restored prairie land cover: 1) how different land management influences infiltration and wetland hydroperiod at the plot scale, 2) the effects of land use on seasonal groundwater-surface water dynamics at the field scale, and 3) seasonal variation in runoff sources and nutrient transport from native prairie and farmed wetlands at the small catchment scale. At the plot scale, our results suggest that edaphic factors, particularly those related to soil structure, are strongly associated with wetland infiltration and overall hydroperiod across least-altered prairie, farmed, and restored prairie mineral flat wetlands. The hydroperiod metrics we examined were generally more sensitive to level of site disturbance than land use alone. At the field scale, our results indicate that, in spite of land use differences and slight variations in soil stratigraphy, many similarities exist in overall wetland hydroperiod, water sources and evaporation rates for mineral flat wetlands in the Willamette Valley lowlands. Isotopic evidence suggests that the greatest degree of groundwater-surface water mixing occurs in the upper 0.5 m of the saturated soil profile across sites under all land uses. Finally, at the small catchment scale, farmed wetland runoff was isotopically similar to field surface water for most of the wet season, indicating that saturation excess was an important runoff generation process. Prairie wetland runoff was isotopically similar to upstream water throughout the winter, and briefly similar to shallow groundwater and surface water within the wetland in mid-spring. Throughout the wet season, elevated nitrate, sulfate, and chloride concentrations were observed in groundwater and surface water at the farm site, and deeper groundwater at the prairie site. Upstream-downstream runoff chemistry remained similar throughout the wet season at the prairie site. Farm site runoff chemistry reflected the dominant water source within the farm field throughout the wet season. Our findings suggest that, while surface water pathways dominate runoff from wetland flats under farm land use, large wetland flat fields have a high potential to absorb, store, and process nutrients and agrochemicals from on-site and nearby off-site chemical inputs. Mineral flats that maintain wetland hydrology in spite of farm use represent a unique balance between agricultural production and preservation of some of the water storage and delay, and water quality-related ecosystem services once provided at a much larger scale in the Willamette Valley lowlands. We anticipate that results of this work will lead to better understanding of key site-scale edaphic and hydrologic factors to consider when prioritizing and managing sites for restoration, and how site disturbance under a variety of land uses may impact different hydrologic processes and components of the wetland hydroperiod. Additionally, our results provide a better understanding of how land use affects seasonal runoff generation processes in mineral flat wetlands, and the water quality implications of modifying groundwater and surface water connectivity between mineral flats and surrounding surface drainage networks. Close

• 9. [Article] What Lies Below: Options to Improve Sustainable Management of U.S./Mexico TransboundaryAquifers

  Globally, as surface water quality and quantity diminishes there is increasing reliance on groundwater to buffer water demands of growing populations. Today in many arid regions around the world aquifer ...

  Citation × Citation Citation Abstract Copy Title: What Lies Below: Options to Improve Sustainable Management of U.S./Mexico TransboundaryAquifers Author: Welch, Christina, N. Globally, as surface water quality and quantity diminishes there is increasing reliance on groundwater to buffer water demands of growing populations. Today in many arid regions around the world aquifer pumping rates far exceed recharge rates. Often the groundwater is nonrenewable, or thousands of years old. Despite the known hydrologic connection between surface and groundwater, existing institutions and laws governing surface water are poorly equipped to manage groundwater. While there are more than 600 international treaties governing surface water, only one treaty worldwide explicitly addresses groundwater allocation. Like many other regions of the world, the treaties covering the Paseo del Norte region shared between Mexico and the United States allocate the quantity and timing of surface water deliveries, yet fail to regulate groundwater abstraction. The three transboundary aquifers shared by two countries and three states (New Mexico/U.S., Texas/U.S., and Chihuahua/MX) within Paseo del Norte study area present an ideal microcosm to closer examine water management institutions across the local, state, national, and international scales. This research assesses the United States and Mexico’s institutional capacity to manage groundwater across each scale. The problem is imminent since the Hueco Bolson transboundary aquifer is the primary source of drinking water for nearly 2 million people and the fresh water is predicted to be completely depleted between 2020-2050. The ultimate objective is to identify which future legal, scientific and economic options can best contribute to more sustainable management of transboundary aquifers without compromising water security in both countries. This research proposes three major paths to move forward: the first step is to increase public awareness of the aquifer exploitation problem; second, for water managers to accurately plan for future water demands there should be a binational groundwater model built by scientists on both sides of the border; third, an international treaty or regional joint agreement is necessary to legally support groundwater management efforts. Title: What Lies Below: Options to Improve Sustainable Management of U.S./Mexico TransboundaryAquifers Author: Welch, Christina, N. Globally, as surface water quality and quantity diminishes there is increasing reliance on groundwater to buffer water demands of growing populations. Today in many arid regions around the world aquifer pumping rates far exceed recharge rates. Often the groundwater is nonrenewable, or thousands of years old. Despite the known hydrologic connection between surface and groundwater, existing institutions and laws governing surface water are poorly equipped to manage groundwater. While there are more than 600 international treaties governing surface water, only one treaty worldwide explicitly addresses groundwater allocation. Like many other regions of the world, the treaties covering the Paseo del Norte region shared between Mexico and the United States allocate the quantity and timing of surface water deliveries, yet fail to regulate groundwater abstraction. The three transboundary aquifers shared by two countries and three states (New Mexico/U.S., Texas/U.S., and Chihuahua/MX) within Paseo del Norte study area present an ideal microcosm to closer examine water management institutions across the local, state, national, and international scales. This research assesses the United States and Mexico’s institutional capacity to manage groundwater across each scale. The problem is imminent since the Hueco Bolson transboundary aquifer is the primary source of drinking water for nearly 2 million people and the fresh water is predicted to be completely depleted between 2020-2050. The ultimate objective is to identify which future legal, scientific and economic options can best contribute to more sustainable management of transboundary aquifers without compromising water security in both countries. This research proposes three major paths to move forward: the first step is to increase public awareness of the aquifer exploitation problem; second, for water managers to accurately plan for future water demands there should be a binational groundwater model built by scientists on both sides of the border; third, an international treaty or regional joint agreement is necessary to legally support groundwater management efforts. Close

• 10. [Article] Economic criteria as normative content in Oregon surface water law

  Citation × Citation Citation Abstract Copy Title: Economic criteria as normative content in Oregon surface water law Author: Whittaker, Gerald W. Title: Economic criteria as normative content in Oregon surface water law Author: Whittaker, Gerald W. Close