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• 1. [Article] Terra ; Vol.6 No.1 (Fall 2010)

  29 pages

  Citation × Citation Citation Abstract Copy Title: Terra ; Vol.6 No.1 (Fall 2010) Author: Houtman, Nicolas, Sherman, Lee, Brown, Aimee Lyn, Yeager, Angela 29 pages Title: Terra ; Vol.6 No.1 (Fall 2010) Author: Houtman, Nicolas, Sherman, Lee, Brown, Aimee Lyn, Yeager, Angela 29 pages Close

• 2. [Article] The Columbia River's fate in the twentieth century

  Discusses the history of the Columbia River during the 20th century, emphasizing the image of the river as both a source of industry and an example of wild natural beauty. In 1933 the river was dammed ...

  Citation × Citation Citation Abstract Copy Title: The Columbia River's fate in the twentieth century Author: Lang, William L. Year: 2000 Discusses the history of the Columbia River during the 20th century, emphasizing the image of the river as both a source of industry and an example of wild natural beauty. In 1933 the river was dammed to harness its power for hydroelectricity and control its unpredictable flooding. With the completion of the dams in the 1970's, however, came problems with the edenic vision of the river, especially with the annual salmon run. By the late 20th century, the salmon had all but disappeared, leading to an ongoing conflict between supporters of the dams and conservationists. Title: The Columbia River's fate in the twentieth century Author: Lang, William L. Year: 2000 Discusses the history of the Columbia River during the 20th century, emphasizing the image of the river as both a source of industry and an example of wild natural beauty. In 1933 the river was dammed to harness its power for hydroelectricity and control its unpredictable flooding. With the completion of the dams in the 1970's, however, came problems with the edenic vision of the river, especially with the annual salmon run. By the late 20th century, the salmon had all but disappeared, leading to an ongoing conflict between supporters of the dams and conservationists. Close

• 3. [Article] Assessing the Current State of Transboundary Cooperation in the International Columbia River Basin

  The Columbia River Treaty (CRT) is often used as an example of how treaties can work to normalize, regulate, and improve the cooperative management of shared water resources between basin countries. Few ...

  Citation × Citation Citation Abstract Copy Title: Assessing the Current State of Transboundary Cooperation in the International Columbia River Basin Author: Timboe, Ingrid A. The Columbia River Treaty (CRT) is often used as an example of how treaties can work to normalize, regulate, and improve the cooperative management of shared water resources between basin countries. Few would argue that, in its limited mandate to regulate hydropower generation and flood risk management for downstream communities, the CRT has been anything but a success. However, there are many aspects of water resource management, including water quality, aquatic species, and indigenous peoples' rights and responsibilities that are left unaddressed by the Treaty. These issues are of increasing importance to managers and stakeholders in river basins around the world. This paper asks, in the absence of a formal agreement governing these issues, are the United States and Canada coordinating the broader management of the Columbia River and its international tributaries? If so, around which water resource issues do they collaborate and at what level? If not, do these gaps in co-management negatively affect the basin? In order to assess the current state of transboundary water cooperation between the United States and Canada within the basin, 50 transboundary initiatives were identified and categorized into management categories including: ecosystem function, fish passage & habitat, climate change, invasive species or toxics management, and energy. Interviews were then conducted with 34 natural resource managers throughout the international basin on their work with these initiatives, specifically addressing areas where they are, and are not, collaborating at this time. The interviews revealed that, while there is a great deal of collaborative work being done, it appears largely fragmented and restricted to sub-basin activities. International, basin-wide cooperation, outside of treaty obligations under the CRT, appears limited at this time. This thesis contends that there is a need for these sub-basin activities to be networked with one another, either through the Treaty, or through an inclusive, legitimate, and transparent river basin organization. Title: Assessing the Current State of Transboundary Cooperation in the International Columbia River Basin Author: Timboe, Ingrid A. The Columbia River Treaty (CRT) is often used as an example of how treaties can work to normalize, regulate, and improve the cooperative management of shared water resources between basin countries. Few would argue that, in its limited mandate to regulate hydropower generation and flood risk management for downstream communities, the CRT has been anything but a success. However, there are many aspects of water resource management, including water quality, aquatic species, and indigenous peoples' rights and responsibilities that are left unaddressed by the Treaty. These issues are of increasing importance to managers and stakeholders in river basins around the world. This paper asks, in the absence of a formal agreement governing these issues, are the United States and Canada coordinating the broader management of the Columbia River and its international tributaries? If so, around which water resource issues do they collaborate and at what level? If not, do these gaps in co-management negatively affect the basin? In order to assess the current state of transboundary water cooperation between the United States and Canada within the basin, 50 transboundary initiatives were identified and categorized into management categories including: ecosystem function, fish passage & habitat, climate change, invasive species or toxics management, and energy. Interviews were then conducted with 34 natural resource managers throughout the international basin on their work with these initiatives, specifically addressing areas where they are, and are not, collaborating at this time. The interviews revealed that, while there is a great deal of collaborative work being done, it appears largely fragmented and restricted to sub-basin activities. International, basin-wide cooperation, outside of treaty obligations under the CRT, appears limited at this time. This thesis contends that there is a need for these sub-basin activities to be networked with one another, either through the Treaty, or through an inclusive, legitimate, and transparent river basin organization. Close

• 4. [Article] Particle Trapping in Stratified Estuaries - Definition of a Parameter Space

  Estuarine turbidity maxima (ETM) retain suspended particulate matter (SPM) through advection, settling, aggregation and non-linearities in bed processes. This contribution defines for the first time a ...

  Citation × Citation Citation Abstract Copy Title: Particle Trapping in Stratified Estuaries - Definition of a Parameter Space Author: Jay, David A., Orton, Philip M., Chisholm, Thomas A., Wilson, Douglas J., Fain, Annika M., McGinity, John Year: 2003 Estuarine turbidity maxima (ETM) retain suspended particulate matter (SPM) through advection, settling, aggregation and non-linearities in bed processes. This contribution defines for the first time a parameter space descriptive of ETM water-column particle trapping processes through a scaling analysis of the local and integral SPM balances. In the absence of long-term deposition, there are five primary parameters for the large particles or aggregates that are typically trapped. Rouse number P, the ratio of settling velocity WS of the SPM relative to the shear velocity U*, describes the material trapped in the ETM in terms of the local vertical balance between vertical mixing and aggregate settling. Advection number A= P ΔU/UT scales the landward transport of SPM by tidal and mean flow processes in terms of flood-ebb velocity difference (ΔU) and maximum tidal current (UT). Supply number SR = P UR/UT defines SPM supply and removal (UR is river flow). Changes in the estuarine inventory of SPM are described in terms of a Trapping Efficiency E, a ratio of peak ETM concentration to fluvial or marine supply concentration. The effects of aggregation in the integral dynamic balance are quantified by a Floc number F that describes the tendency of aggregates to form through shear-driven collisions. This study uses observations from two strongly advective systems (the Columbia and Fraser Rivers) plus literature values from 13 other estuaries to illustrate the applicability of the above scaling. The primary question investigated is the relationship of trapping efficiency E and Floc number F to other parameters, especially river flow (expressed in terms of supply number SR). The strongest SPM trapping (high E) occurs in mid-ETM, where A ~0. The extreme high flows observed in the Fraser River estuary show how ETM trapping becomes ineffective as the estuary length contracts to one tidal excursion or less (limit of high SR). Use of data from all 15 estuaries shows that there is a strong trend toward more efficient trapping for low SR. E and F are positively correlated, so that aggregation becomes more prominent in systems with weak to moderate river flow. Examination of tidal monthly and seasonal particle properties at four closely-spaced moorings in the Columbia emphasize the importance of strong ETM gradients – particle properties are diverse even when the hydrodynamic regime is apparently similar. Finally, scaling variables and data are combined to express ETM properties in terms of U*, UR and UT.. Title: Particle Trapping in Stratified Estuaries - Definition of a Parameter Space Author: Jay, David A., Orton, Philip M., Chisholm, Thomas A., Wilson, Douglas J., Fain, Annika M., McGinity, John Year: 2003 Estuarine turbidity maxima (ETM) retain suspended particulate matter (SPM) through advection, settling, aggregation and non-linearities in bed processes. This contribution defines for the first time a parameter space descriptive of ETM water-column particle trapping processes through a scaling analysis of the local and integral SPM balances. In the absence of long-term deposition, there are five primary parameters for the large particles or aggregates that are typically trapped. Rouse number P, the ratio of settling velocity WS of the SPM relative to the shear velocity U*, describes the material trapped in the ETM in terms of the local vertical balance between vertical mixing and aggregate settling. Advection number A= P ΔU/UT scales the landward transport of SPM by tidal and mean flow processes in terms of flood-ebb velocity difference (ΔU) and maximum tidal current (UT). Supply number SR = P UR/UT defines SPM supply and removal (UR is river flow). Changes in the estuarine inventory of SPM are described in terms of a Trapping Efficiency E, a ratio of peak ETM concentration to fluvial or marine supply concentration. The effects of aggregation in the integral dynamic balance are quantified by a Floc number F that describes the tendency of aggregates to form through shear-driven collisions. This study uses observations from two strongly advective systems (the Columbia and Fraser Rivers) plus literature values from 13 other estuaries to illustrate the applicability of the above scaling. The primary question investigated is the relationship of trapping efficiency E and Floc number F to other parameters, especially river flow (expressed in terms of supply number SR). The strongest SPM trapping (high E) occurs in mid-ETM, where A ~0. The extreme high flows observed in the Fraser River estuary show how ETM trapping becomes ineffective as the estuary length contracts to one tidal excursion or less (limit of high SR). Use of data from all 15 estuaries shows that there is a strong trend toward more efficient trapping for low SR. E and F are positively correlated, so that aggregation becomes more prominent in systems with weak to moderate river flow. Examination of tidal monthly and seasonal particle properties at four closely-spaced moorings in the Columbia emphasize the importance of strong ETM gradients – particle properties are diverse even when the hydrodynamic regime is apparently similar. Finally, scaling variables and data are combined to express ETM properties in terms of U*, UR and UT.. Close