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• 1. [Article] A Stable Isotopic Investigation of a Polar Desert Hydrologic System, McMurdo Dry Valleys, Antarctica

  The hydrologic system of the coastal McMurdo Dry Valleys, Antarctica, is defined by snow accumulation, glacier melt, stream flow, and retention in closed-basin, ice-covered lakes. During the austral summers ...

  Citation × Citation Citation Abstract Copy Title: A Stable Isotopic Investigation of a Polar Desert Hydrologic System, McMurdo Dry Valleys, Antarctica Author: Gooseff, Michael N., Lyons, W. Berry, McKnight, Diane M., Vaughn, Bruce H., Fountain, Andrew G., Dowling, Carolyn Year: 2006 The hydrologic system of the coastal McMurdo Dry Valleys, Antarctica, is defined by snow accumulation, glacier melt, stream flow, and retention in closed-basin, ice-covered lakes. During the austral summers from 1993-1996 and 1999-2000 to 2002-2003, fresh snow, snow pits, glacier ice, stream water, and lake waters were sampled for the stable isotopes deuterium (D) and 18O in order to resolve sources of meltwater and the interactions among the various hydrologic reservoirs in the dry valleys. This data set provides a survey of the distribution of natural water isotope abundances within the well-defined dry valley hydrologic system in Taylor Valley, which extends 20 km inland from McMurdo Sound. The three major Taylor Valley lakes are not connected to one another hydrologically, and their levels are maintained by glacial meltwater inflow and perennial ice-cover sublimation. At the valley scale, glacial ice, snow, stream, and lake waters become more depleted in delta D with increasing distance from McMurdo Sound (further inland). Snow pack in glacial accumulation zones is heterogeneous, likely a result of varying storm sources (continental versus coastal), and, in general, snow pits, fresh snow samples, and glacier ice are more depleted than stream waters. Within the lake basins, glacial ice source waters are depleted by as much as 111ppm delta D and 20 ppm delta 18O compared to lake waters. These results demonstrate the importance of in-stream fractionation at the valley scale. In-stream fractionation occurs through direct evaporation from the channel and hyporheic exchange with isotopically enriched waters in the near-stream subsurface during transport from the glacial source to lake. Furthermore, the results show that lake waters directly reflect their glacial ice sources, despite fractionation during stream transport. Inter-annual comparisons of lake profiles suggest that lake waters are directly influenced by the isotopic composition and amount of stream flow during a season. Title: A Stable Isotopic Investigation of a Polar Desert Hydrologic System, McMurdo Dry Valleys, Antarctica Author: Gooseff, Michael N., Lyons, W. Berry, McKnight, Diane M., Vaughn, Bruce H., Fountain, Andrew G., Dowling, Carolyn Year: 2006 The hydrologic system of the coastal McMurdo Dry Valleys, Antarctica, is defined by snow accumulation, glacier melt, stream flow, and retention in closed-basin, ice-covered lakes. During the austral summers from 1993-1996 and 1999-2000 to 2002-2003, fresh snow, snow pits, glacier ice, stream water, and lake waters were sampled for the stable isotopes deuterium (D) and 18O in order to resolve sources of meltwater and the interactions among the various hydrologic reservoirs in the dry valleys. This data set provides a survey of the distribution of natural water isotope abundances within the well-defined dry valley hydrologic system in Taylor Valley, which extends 20 km inland from McMurdo Sound. The three major Taylor Valley lakes are not connected to one another hydrologically, and their levels are maintained by glacial meltwater inflow and perennial ice-cover sublimation. At the valley scale, glacial ice, snow, stream, and lake waters become more depleted in delta D with increasing distance from McMurdo Sound (further inland). Snow pack in glacial accumulation zones is heterogeneous, likely a result of varying storm sources (continental versus coastal), and, in general, snow pits, fresh snow samples, and glacier ice are more depleted than stream waters. Within the lake basins, glacial ice source waters are depleted by as much as 111ppm delta D and 20 ppm delta 18O compared to lake waters. These results demonstrate the importance of in-stream fractionation at the valley scale. In-stream fractionation occurs through direct evaporation from the channel and hyporheic exchange with isotopically enriched waters in the near-stream subsurface during transport from the glacial source to lake. Furthermore, the results show that lake waters directly reflect their glacial ice sources, despite fractionation during stream transport. Inter-annual comparisons of lake profiles suggest that lake waters are directly influenced by the isotopic composition and amount of stream flow during a season. Close

• 2. [Article] Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures

  Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each ...

  Citation × Citation Citation Abstract Copy Title: Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures Author: Berger, Chris, Wells, Scott A. Year: 2007 Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each of these forcing functions is directly influenced by the level of channel complexity in the stream channel and riparian shading. The interrelationship between channel complexity, hyporheic flow and stream temperature is highly complex, and efforts to manage for habitat diversity by managing channel complexity could result in unintended consequences on stream temperature. When planning modifications to stream channel complexity, consideration should be given to the effects such moderations could have on stream temperatures. Urbanization has impacted many steams due to the construction of bank protections, levees, vegetation removal, etc. Such activities have eliminated side channels and reduced stream braiding, thereby reducing the overall channel complexity. Hulse et al. (2002) developed maps showing the channel configurations of the Willamette River in Oregon, USA in the years 1850 and 1995. These maps show a significant reduction in channel complexity in the intervening years. More complex stream channels provide greater habitat diversity and thus, are generally more desirable from a wildlife management perspective. Therefore, management of streams for increased channel complexity is gaining in popularity. Knowing that stream channel complexity has diminished over time, an important question to consider is ‘what were stream temperatures before we altered the natural channels?’ This is an important issue in determining what natural conditions were and how we have strayed from these so-called ‘natural’ conditions as a result of channelization, dam building, and changes to the riparian vegetation and deforestation. Current Total Maximum Daily Load’s (TMDL) rely on determining a ‘natural’ condition. In order to develop an understanding of what that is, a hydrodynamic and water quality computer simulation model has been applied to Oregon’s Willamette River with several levels of channel complexity and varying rates of hyporheic flows. Adapting the model used to develop TMDL’s for temperature in the Willamette River, the effects of present and past channel complexity on water temperatures was determined. The model used to develop the TMDL was the U. S. Army Corps of Engineers dynamic 2-D model CE-QUAL-W2, which consists of directly coupled hydrodynamic and water quality transport models and simulates parameters such as temperature, algae concentration, dissolved oxygen concentration, pH, nutrient concentrations and residence time. The model also incorporates a dynamic shading algorithm for both vegetative and topographic shading on water bodies. Title: Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures Author: Berger, Chris, Wells, Scott A. Year: 2007 Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each of these forcing functions is directly influenced by the level of channel complexity in the stream channel and riparian shading. The interrelationship between channel complexity, hyporheic flow and stream temperature is highly complex, and efforts to manage for habitat diversity by managing channel complexity could result in unintended consequences on stream temperature. When planning modifications to stream channel complexity, consideration should be given to the effects such moderations could have on stream temperatures. Urbanization has impacted many steams due to the construction of bank protections, levees, vegetation removal, etc. Such activities have eliminated side channels and reduced stream braiding, thereby reducing the overall channel complexity. Hulse et al. (2002) developed maps showing the channel configurations of the Willamette River in Oregon, USA in the years 1850 and 1995. These maps show a significant reduction in channel complexity in the intervening years. More complex stream channels provide greater habitat diversity and thus, are generally more desirable from a wildlife management perspective. Therefore, management of streams for increased channel complexity is gaining in popularity. Knowing that stream channel complexity has diminished over time, an important question to consider is ‘what were stream temperatures before we altered the natural channels?’ This is an important issue in determining what natural conditions were and how we have strayed from these so-called ‘natural’ conditions as a result of channelization, dam building, and changes to the riparian vegetation and deforestation. Current Total Maximum Daily Load’s (TMDL) rely on determining a ‘natural’ condition. In order to develop an understanding of what that is, a hydrodynamic and water quality computer simulation model has been applied to Oregon’s Willamette River with several levels of channel complexity and varying rates of hyporheic flows. Adapting the model used to develop TMDL’s for temperature in the Willamette River, the effects of present and past channel complexity on water temperatures was determined. The model used to develop the TMDL was the U. S. Army Corps of Engineers dynamic 2-D model CE-QUAL-W2, which consists of directly coupled hydrodynamic and water quality transport models and simulates parameters such as temperature, algae concentration, dissolved oxygen concentration, pH, nutrient concentrations and residence time. The model also incorporates a dynamic shading algorithm for both vegetative and topographic shading on water bodies. Close

• 3. [Article] Changes in hyporheic exchange flow following experimental wood removal in a small, low-gradient stream

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/.

  Citation × Citation Citation Abstract Copy Title: Changes in hyporheic exchange flow following experimental wood removal in a small, low-gradient stream Author: Haggerty, Roy, Edwards, Richard T., LaNier, Justin, Wondzell, Steven M., Woodsmith, Richard D. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/. Title: Changes in hyporheic exchange flow following experimental wood removal in a small, low-gradient stream Author: Haggerty, Roy, Edwards, Richard T., LaNier, Justin, Wondzell, Steven M., Woodsmith, Richard D. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/. Close

• 4. [Article] Determining in-channel (dead zone) transient storage by comparing solute transport in a bedrock channel–alluvial channel sequence, Oregon

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/.

  Citation × Citation Citation Abstract Copy Title: Determining in-channel (dead zone) transient storage by comparing solute transport in a bedrock channel–alluvial channel sequence, Oregon Author: Haggerty, Roy, Gooseff, Michael N., LaNier, Justin, Kokkeler, Kenneth This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/. Title: Determining in-channel (dead zone) transient storage by comparing solute transport in a bedrock channel–alluvial channel sequence, Oregon Author: Haggerty, Roy, Gooseff, Michael N., LaNier, Justin, Kokkeler, Kenneth This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/. Close

• 5. [Article] A fluid-mechanics based classification scheme for surface transient storage in riverine environments: quantitatively separating surface from hyporheic transient storage

  This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: [http://publications.copernicus.org/.

  Citation × Citation Citation Abstract Copy Title: A fluid-mechanics based classification scheme for surface transient storage in riverine environments: quantitatively separating surface from hyporheic transient storage Author: Jackson, T. R., Haggerty, R., Apte, Sourabh V. This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: [http://publications.copernicus.org/. Title: A fluid-mechanics based classification scheme for surface transient storage in riverine environments: quantitatively separating surface from hyporheic transient storage Author: Jackson, T. R., Haggerty, R., Apte, Sourabh V. This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: [http://publications.copernicus.org/. Close

• 6. [Article] Spatial and Temporal Variability of Macroinvertebrates in Spawning and Non-Spawning Habitats during a Salmon Run in Southeast Alaska

  This is the publisher’s final pdf. The published article is copyrighted by PLoS ONE and can be found at: http://www.plosone.org/home.action.

  Citation × Citation Citation Abstract Copy Title: Spatial and Temporal Variability of Macroinvertebrates in Spawning and Non-Spawning Habitats during a Salmon Run in Southeast Alaska Author: Merritt, Richard W., Campbell, Emily Y., Benbow, M. Eric, Cummins, Kenneth W. This is the publisher’s final pdf. The published article is copyrighted by PLoS ONE and can be found at: http://www.plosone.org/home.action. Title: Spatial and Temporal Variability of Macroinvertebrates in Spawning and Non-Spawning Habitats during a Salmon Run in Southeast Alaska Author: Merritt, Richard W., Campbell, Emily Y., Benbow, M. Eric, Cummins, Kenneth W. This is the publisher’s final pdf. The published article is copyrighted by PLoS ONE and can be found at: http://www.plosone.org/home.action. Close

• 7. [Article] Geomorphic controls on hyporheic exchange flow in mountain streams

  Simulations of stream-subsurface water exchange (hyporheic exchange) using a three-dimensional steady state groundwater flow model and a particle tracking model in unconstrained and constrained reaches ...

  Citation × Citation Citation Abstract Copy Title: Geomorphic controls on hyporheic exchange flow in mountain streams Author: Kasahara, Tamao Simulations of stream-subsurface water exchange (hyporheic exchange) using a three-dimensional steady state groundwater flow model and a particle tracking model in unconstrained and constrained reaches of small (2nd-order) and intermediate (5th-order) mountain streams were conducted to estimate the effects of geomorphic features on the extent, volume and residence time of hyporheic exchange flow. Study sites were located in the Lookout Creek drainage in the western Cascades of Oregon. Stream water and water table elevations and saturated hydraulic conductivity were collected from four field sites. Steps were the dominant geomorphic features creating vertical complexity in 2nd-order streams and dominating hyporheic exchange flow. The removal of steps from the simulation models of 2nd-order stream reduced the total volume of hyporheic exchange by 54 %. Furthermore, hyporheic exchange flows resulting from steps had relatively short residence times. Horizontal complexity, resulting from secondary channels and channel splits, had strong effects on hyporheic exchange, as did vertically extensive features, such as riffles, in 5th-order streams. Removal of secondary channels, channel splits and riffles from the simulation models reduced hyporheic exchange flow by 25 %, 30 % and 40 %, respectively. Secondary channels contributed to hyporheic exchange with relatively long residence time, where as channel splits and riffles contributed to hyporheic exchange with short residence time. Thus, multiple features strongly contributed to the creation of hyporheic exchange flow and drove various types of the exchange flows. Also, the simulation results and stream survey showed that the interactions between multiple features, for example secondary channels and riffles, enhanced hyporheic exchange. Because horizontally extensive features were important in driving hyporheic exchange flow in the studied unconstrained reaches, the width of the valley floor strongly controlled hyporheic exchange flow in 5th-order streams. Geomorphic controls on hyporheic exchange flow differed between the two stream sizes sampled. Second-order streams had a single key geomorphic feature (i.e. steps) influencing the hyporheic exchange flow, whereas multiple geomorphic features (i.e. riffles, secondary channels and channel splits) were important in 5 b-order streams. As a result, residence time distribution of hyporheic exchange flow was narrow in 2nd- order stream and wide in 5th-order stream. Title: Geomorphic controls on hyporheic exchange flow in mountain streams Author: Kasahara, Tamao Simulations of stream-subsurface water exchange (hyporheic exchange) using a three-dimensional steady state groundwater flow model and a particle tracking model in unconstrained and constrained reaches of small (2nd-order) and intermediate (5th-order) mountain streams were conducted to estimate the effects of geomorphic features on the extent, volume and residence time of hyporheic exchange flow. Study sites were located in the Lookout Creek drainage in the western Cascades of Oregon. Stream water and water table elevations and saturated hydraulic conductivity were collected from four field sites. Steps were the dominant geomorphic features creating vertical complexity in 2nd-order streams and dominating hyporheic exchange flow. The removal of steps from the simulation models of 2nd-order stream reduced the total volume of hyporheic exchange by 54 %. Furthermore, hyporheic exchange flows resulting from steps had relatively short residence times. Horizontal complexity, resulting from secondary channels and channel splits, had strong effects on hyporheic exchange, as did vertically extensive features, such as riffles, in 5th-order streams. Removal of secondary channels, channel splits and riffles from the simulation models reduced hyporheic exchange flow by 25 %, 30 % and 40 %, respectively. Secondary channels contributed to hyporheic exchange with relatively long residence time, where as channel splits and riffles contributed to hyporheic exchange with short residence time. Thus, multiple features strongly contributed to the creation of hyporheic exchange flow and drove various types of the exchange flows. Also, the simulation results and stream survey showed that the interactions between multiple features, for example secondary channels and riffles, enhanced hyporheic exchange. Because horizontally extensive features were important in driving hyporheic exchange flow in the studied unconstrained reaches, the width of the valley floor strongly controlled hyporheic exchange flow in 5th-order streams. Geomorphic controls on hyporheic exchange flow differed between the two stream sizes sampled. Second-order streams had a single key geomorphic feature (i.e. steps) influencing the hyporheic exchange flow, whereas multiple geomorphic features (i.e. riffles, secondary channels and channel splits) were important in 5 b-order streams. As a result, residence time distribution of hyporheic exchange flow was narrow in 2nd- order stream and wide in 5th-order stream. Close

• 8. [Article] Patterns in stream geomorphology and implications for hyporheic exchange flow

  Longitudinal water surface profiles from high-gradient mountain streams provide useful indicators of the relative potential for hyporheic exchange flow in stream reaches with varying morphology. The spacing ...

  Citation × Citation Citation Abstract Copy Title: Patterns in stream geomorphology and implications for hyporheic exchange flow Author: Anderson, Justin K. Longitudinal water surface profiles from high-gradient mountain streams provide useful indicators of the relative potential for hyporheic exchange flow in stream reaches with varying morphology. The spacing between slope breaks in step-pool and pool-riffle streams provides a geomorphic scaling metric that indicates how the length of average hyporheic flow paths change throughout the river continuum. Twelve stream reaches were randomly selected and surveyed in the Lookout Creek basin at the H.J. Andrews Experimental Forest in the western Cascades Mountains of Oregon. Stream reach morphology was examined for patterns that are expressed over a continuum ranging from headwater to mid-order streams that can be predicted from easily measured drainage basin characteristics. Simple and multiple linear regression models were used to predict changes in lateral complexity in stream reaches, and to predict how the general shape of the water surface profile changes as drainage basin area increases from 0.6 km² to 62.3 km². Patterns in the lateral complexity of stream reaches were associated with the degree of channel confinement in valley segments, and longitudinal patterns in bed configuration were strongly associated with the position of a stream reach within the river continuum. Stream reach longitudinal profiles were evaluated to determine how patterns in slope breaks change throughout the portion of the river continuum represented by the study area. Channel units were defined according to slope categories for flat water, steep water, and step units (FLATs, STEEPs and STEPs). A set of regression models was used to predict how slope break spacing and the general shape of the water surface profile change as drainage basin area increases from 0.6 km² to 62.3 km². Output from these regression equations was tested against independent field data to evaluate model performance. The models generally performed well. Longitudinal transects of piezometers were installed along the thalweg of a second order, and a third order stream reach. Longitudinal profiles in the piezometer transects were surveyed, and piezometers were used to measure hydraulic head in stream beds. Data were used to test a theoretical model that predicts downwelling where stream profiles are convex, and upwelling where stream profiles are concave. Overall, the shape of the water surface profile explained 38% of the variation in the distribution of hydraulic pressure head in the streambed. Results demonstrated the usefulness of quantifying the magnitude of concavities and convexities in stream profiles. A metric for expressing the average water surface concavity (AWSC) is proposed. I demonstrated that this metric could be useful for comparing the potential for hyporheic exchange in stream reaches with varying degrees of stream profile roughness. Results showed a decreasing trend in AWSC as drainage basin area increased. Upwelling and downwelling zones were identified in piezometer transects, and their longitudinal lengths were measured. The lengths of downwelling zones were compared to the spacing between slope breaks in the water surface profile. Average lengths of downwelling zones and FLAT channel slope units increased with increasing basin area at a similar rate, indicating that slope break spacing was a useful indicator for average downwelling zone length. My results demonstrate that patterns in stream morphology are useful for predicting patterns in hyporheic exchange flow throughout the river continuum. I suggest that the potential for gravity driven exchange flow decreases along the river continuum as AWSC decreases. I also suggest that the frequency of hydrologic exchange between the stream and the hyporheic zone decreases, and that the average length of hyporheic flow paths increase, across the river continuum. Title: Patterns in stream geomorphology and implications for hyporheic exchange flow Author: Anderson, Justin K. Longitudinal water surface profiles from high-gradient mountain streams provide useful indicators of the relative potential for hyporheic exchange flow in stream reaches with varying morphology. The spacing between slope breaks in step-pool and pool-riffle streams provides a geomorphic scaling metric that indicates how the length of average hyporheic flow paths change throughout the river continuum. Twelve stream reaches were randomly selected and surveyed in the Lookout Creek basin at the H.J. Andrews Experimental Forest in the western Cascades Mountains of Oregon. Stream reach morphology was examined for patterns that are expressed over a continuum ranging from headwater to mid-order streams that can be predicted from easily measured drainage basin characteristics. Simple and multiple linear regression models were used to predict changes in lateral complexity in stream reaches, and to predict how the general shape of the water surface profile changes as drainage basin area increases from 0.6 km² to 62.3 km². Patterns in the lateral complexity of stream reaches were associated with the degree of channel confinement in valley segments, and longitudinal patterns in bed configuration were strongly associated with the position of a stream reach within the river continuum. Stream reach longitudinal profiles were evaluated to determine how patterns in slope breaks change throughout the portion of the river continuum represented by the study area. Channel units were defined according to slope categories for flat water, steep water, and step units (FLATs, STEEPs and STEPs). A set of regression models was used to predict how slope break spacing and the general shape of the water surface profile change as drainage basin area increases from 0.6 km² to 62.3 km². Output from these regression equations was tested against independent field data to evaluate model performance. The models generally performed well. Longitudinal transects of piezometers were installed along the thalweg of a second order, and a third order stream reach. Longitudinal profiles in the piezometer transects were surveyed, and piezometers were used to measure hydraulic head in stream beds. Data were used to test a theoretical model that predicts downwelling where stream profiles are convex, and upwelling where stream profiles are concave. Overall, the shape of the water surface profile explained 38% of the variation in the distribution of hydraulic pressure head in the streambed. Results demonstrated the usefulness of quantifying the magnitude of concavities and convexities in stream profiles. A metric for expressing the average water surface concavity (AWSC) is proposed. I demonstrated that this metric could be useful for comparing the potential for hyporheic exchange in stream reaches with varying degrees of stream profile roughness. Results showed a decreasing trend in AWSC as drainage basin area increased. Upwelling and downwelling zones were identified in piezometer transects, and their longitudinal lengths were measured. The lengths of downwelling zones were compared to the spacing between slope breaks in the water surface profile. Average lengths of downwelling zones and FLAT channel slope units increased with increasing basin area at a similar rate, indicating that slope break spacing was a useful indicator for average downwelling zone length. My results demonstrate that patterns in stream morphology are useful for predicting patterns in hyporheic exchange flow throughout the river continuum. I suggest that the potential for gravity driven exchange flow decreases along the river continuum as AWSC decreases. I also suggest that the frequency of hydrologic exchange between the stream and the hyporheic zone decreases, and that the average length of hyporheic flow paths increase, across the river continuum. Close

• 9. [Article] Economic analysis of restoration practices to improve water quality and fish habitat of a large river floodplain : a case study of the Willamette River, Oregon

  In- stream water temperature is one of the most important environmental factors associated with the decline in salmonid populations and their habitats in the Pacific Northwest. Most ecological restoration ...

  Citation × Citation Citation Abstract Copy Title: Economic analysis of restoration practices to improve water quality and fish habitat of a large river floodplain : a case study of the Willamette River, Oregon Author: Seedang, Saichon In- stream water temperature is one of the most important environmental factors associated with the decline in salmonid populations and their habitats in the Pacific Northwest. Most ecological restoration practices that attempt to reduce instream temperatures center on replanting or reestablishing riparian vegetation and increasing flows. However, in a large floodplain river like the Willamette, restoring hyporheic flow may also play an important role in reducing water temperature. The objective of this dissertation is to examine restoration practices that focus on the reduction of water temperatures in the upper mainstem Willamette River, Oregon, for the benefit of salmonid species. Economic information is developed to determine the cost-effectiveness of water temperature reduction strategies. The CEQUAL- W2 water temperature model is used to simulate the effects of upstream combinations of riparian shading and flow increments on downstream water temperatures. Costs associated with these strategies are estimated. These costs consist of the opportunity costs of losing agricultural production, and losing recreation due to flow releases from up-stream reservoirs. The effectiveness of each strategy in reducing water temperature and the associated costs are used to construct a cost-effectiveness frontier. The results indicate that the cumulative effects of shading and flows have little impact on temperature reduction downstream. Even when maximum available resources are allocated to investments in shade and flow increases they cannot lower summer water temperatures sufficiently to meet the state water temperature standard. However, the restoration practices selected from the cost-effectiveness frontiers method do provide ranges of achievable temperature reductions at minimum costs. These results are thus useful management tools when selecting policies to pursue water temperature goals. Hyporheic temperature reduction is also examined. Restoration practices associated with this type of cooling are done through removal/reconnection of the obstacles that are necessary to allow the process of re-creating dynamic channel complexity. The observed significant reduction of summer water temperatures associated with channel complexity indicates that this approach is more flexible in reducing temperature than approaches that rely on flow increments or/and shade. Although the costs associated with the hyporheic approach are substantial, the effects of such a long-term ecological improvement of floodplain habitat may substantially benefit salmonid populations. Title: Economic analysis of restoration practices to improve water quality and fish habitat of a large river floodplain : a case study of the Willamette River, Oregon Author: Seedang, Saichon In- stream water temperature is one of the most important environmental factors associated with the decline in salmonid populations and their habitats in the Pacific Northwest. Most ecological restoration practices that attempt to reduce instream temperatures center on replanting or reestablishing riparian vegetation and increasing flows. However, in a large floodplain river like the Willamette, restoring hyporheic flow may also play an important role in reducing water temperature. The objective of this dissertation is to examine restoration practices that focus on the reduction of water temperatures in the upper mainstem Willamette River, Oregon, for the benefit of salmonid species. Economic information is developed to determine the cost-effectiveness of water temperature reduction strategies. The CEQUAL- W2 water temperature model is used to simulate the effects of upstream combinations of riparian shading and flow increments on downstream water temperatures. Costs associated with these strategies are estimated. These costs consist of the opportunity costs of losing agricultural production, and losing recreation due to flow releases from up-stream reservoirs. The effectiveness of each strategy in reducing water temperature and the associated costs are used to construct a cost-effectiveness frontier. The results indicate that the cumulative effects of shading and flows have little impact on temperature reduction downstream. Even when maximum available resources are allocated to investments in shade and flow increases they cannot lower summer water temperatures sufficiently to meet the state water temperature standard. However, the restoration practices selected from the cost-effectiveness frontiers method do provide ranges of achievable temperature reductions at minimum costs. These results are thus useful management tools when selecting policies to pursue water temperature goals. Hyporheic temperature reduction is also examined. Restoration practices associated with this type of cooling are done through removal/reconnection of the obstacles that are necessary to allow the process of re-creating dynamic channel complexity. The observed significant reduction of summer water temperatures associated with channel complexity indicates that this approach is more flexible in reducing temperature than approaches that rely on flow increments or/and shade. Although the costs associated with the hyporheic approach are substantial, the effects of such a long-term ecological improvement of floodplain habitat may substantially benefit salmonid populations. Close

• 10. [Article] Quantifying spatial differences in metabolism in headwater streams

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Society for Freshwater Science and published by The University of Chicago Press. ...

  Citation × Citation Citation Abstract Copy Title: Quantifying spatial differences in metabolism in headwater streams Author: Haggerty, Roy, Argerich, Alba, Gonzalez-Pinzon, Ricardo This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Society for Freshwater Science and published by The University of Chicago Press. It can be found at: https://www.freshwater-science.org/Journal/Access-FWS.aspx Title: Quantifying spatial differences in metabolism in headwater streams Author: Haggerty, Roy, Argerich, Alba, Gonzalez-Pinzon, Ricardo This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Society for Freshwater Science and published by The University of Chicago Press. It can be found at: https://www.freshwater-science.org/Journal/Access-FWS.aspx Close