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• 1. [Article] Analysis of Dam-Induced Cyclic Patterns on River Flow Dynamics

  This paper investigates the impact of the Hungry Horse Dam on streamflow dynamics in the South Fork of the Flathead River, Montana, USA. To this end, pre- and post-dam periods of raw and naturalized streamflow ...

  Citation × Citation Citation Abstract Copy Title: Analysis of Dam-Induced Cyclic Patterns on River Flow Dynamics Author: Tongal, Hakan, Demirel, Mehmet C., Moradkhani, Hamid Year: 2016 This paper investigates the impact of the Hungry Horse Dam on streamflow dynamics in the South Fork of the Flathead River, Montana, USA. To this end, pre- and post-dam periods of raw and naturalized streamflow data were analysed. Pettitt’s change point analysis indicated a significant change point in streamflow dynamics due to dam construction. Complexities in the pre- and post-dam periods were evaluated by sample and multi-scale entropy analyses, and the entropies of the post-dam period were found to be higher than those of the pre-dam period. Possible reasons for this, unrelated to the natural hydrological cycle caused by the dam, were analysed using wavelet analyses. The wavelet analyses showed a clear change in the phase relationship between precipitation and streamflow. Finally, weak positive trends found in the hydrological variables indicated the effects of human activities (e.g. dam construction). The results also revealed distorted lead times, which can improve the streamflow forecasts for different lead times. Title: Analysis of Dam-Induced Cyclic Patterns on River Flow Dynamics Author: Tongal, Hakan, Demirel, Mehmet C., Moradkhani, Hamid Year: 2016 This paper investigates the impact of the Hungry Horse Dam on streamflow dynamics in the South Fork of the Flathead River, Montana, USA. To this end, pre- and post-dam periods of raw and naturalized streamflow data were analysed. Pettitt’s change point analysis indicated a significant change point in streamflow dynamics due to dam construction. Complexities in the pre- and post-dam periods were evaluated by sample and multi-scale entropy analyses, and the entropies of the post-dam period were found to be higher than those of the pre-dam period. Possible reasons for this, unrelated to the natural hydrological cycle caused by the dam, were analysed using wavelet analyses. The wavelet analyses showed a clear change in the phase relationship between precipitation and streamflow. Finally, weak positive trends found in the hydrological variables indicated the effects of human activities (e.g. dam construction). The results also revealed distorted lead times, which can improve the streamflow forecasts for different lead times. Close

• 2. [Article] Removing Dams, Constructing Science: Coproduction of Undammed Riverscapes by Politics, Finance, Environment, Society and Technology

  Dam removal in the United States has continued to increase in pace and scope, transitioning from a dam-safety engineering practice to an integral component of many large-scale river restoration programmes. ...

  Citation × Citation Citation Abstract Copy Title: Removing Dams, Constructing Science: Coproduction of Undammed Riverscapes by Politics, Finance, Environment, Society and Technology Author: Grabowski, Zbigniew J., Denton, Ashlie, Rozance, Mary Ann, Matsler, Marissa, Kidd, Sarah Year: 2017 Dam removal in the United States has continued to increase in pace and scope, transitioning from a dam-safety engineering practice to an integral component of many large-scale river restoration programmes. At the same time, knowledge around dam removals remains fragmented by disciplinary silos and a lack of knowledge transfer between communities of practice around dam removal and academia. Here we argue that dam removal science, as a study of large restoration-oriented infrastructure interventions, requires the construction of an interdisciplinary framework to integrate knowledge relevant to decision-making on dam removal. Drawing upon infrastructure studies, relational theories of coproduction of knowledge and social life, and advances within restoration ecology and dam removal science, we present a preliminary framework of dams as systems with irreducibly interrelated political, financial, environmental, social, and technological dimensions (PFESTS). With this framework we analyse three dam removals occurring over a similar time period and within the same narrow geographic region (the Mid-Columbia Region in WA and OR, USA) to demonstrate how each PFESTS dimension contributed to the decision to remove the dam, how it affected the process of removing the dam, and how those dimensions continue to operate post removal in each watershed. We conclude with a discussion of a joint research and practice agenda emerging out of the PFESTS framing. Title: Removing Dams, Constructing Science: Coproduction of Undammed Riverscapes by Politics, Finance, Environment, Society and Technology Author: Grabowski, Zbigniew J., Denton, Ashlie, Rozance, Mary Ann, Matsler, Marissa, Kidd, Sarah Year: 2017 Dam removal in the United States has continued to increase in pace and scope, transitioning from a dam-safety engineering practice to an integral component of many large-scale river restoration programmes. At the same time, knowledge around dam removals remains fragmented by disciplinary silos and a lack of knowledge transfer between communities of practice around dam removal and academia. Here we argue that dam removal science, as a study of large restoration-oriented infrastructure interventions, requires the construction of an interdisciplinary framework to integrate knowledge relevant to decision-making on dam removal. Drawing upon infrastructure studies, relational theories of coproduction of knowledge and social life, and advances within restoration ecology and dam removal science, we present a preliminary framework of dams as systems with irreducibly interrelated political, financial, environmental, social, and technological dimensions (PFESTS). With this framework we analyse three dam removals occurring over a similar time period and within the same narrow geographic region (the Mid-Columbia Region in WA and OR, USA) to demonstrate how each PFESTS dimension contributed to the decision to remove the dam, how it affected the process of removing the dam, and how those dimensions continue to operate post removal in each watershed. We conclude with a discussion of a joint research and practice agenda emerging out of the PFESTS framing. Close

• 3. [Article] Current DAMS In 3D: Access, Storage, And Preservation

  The digital asset management systems (DAMS) landscape is rapidly evolving, and many new products have become available in the past few years. DAMS tend to vary widely in terms of scope, technical specifications, ...

  Citation × Citation Citation Abstract Copy Title: Current DAMS In 3D: Access, Storage, And Preservation Author: Burgess, Joanna, Estlund, Karen Year: 2011 The digital asset management systems (DAMS) landscape is rapidly evolving, and many new products have become available in the past few years. DAMS tend to vary widely in terms of scope, technical specifications, functionality, usability, and price point – so DAMS evaluations can be somewhat complex. The Orbis Cascade Alliance appointed a Digital Services Team to evaluate DAMS and consider offering an affordable digital repository platform for members. DAMS can fulfill a range of needs. Typical goals for libraries and archives include enabling access to digital content and providing short or long-term storage for digital objects and data. More recently, digital preservation (practices that ensure continued access to digital objects over time) has also emerged as a critical concern of libraries and cultural heritage institutions. What do access, storage, and preservation mean for your institution? An awareness of institutional or collaborative goals is key to a successful DAMS implementation. Title: Current DAMS In 3D: Access, Storage, And Preservation Author: Burgess, Joanna, Estlund, Karen Year: 2011 The digital asset management systems (DAMS) landscape is rapidly evolving, and many new products have become available in the past few years. DAMS tend to vary widely in terms of scope, technical specifications, functionality, usability, and price point – so DAMS evaluations can be somewhat complex. The Orbis Cascade Alliance appointed a Digital Services Team to evaluate DAMS and consider offering an affordable digital repository platform for members. DAMS can fulfill a range of needs. Typical goals for libraries and archives include enabling access to digital content and providing short or long-term storage for digital objects and data. More recently, digital preservation (practices that ensure continued access to digital objects over time) has also emerged as a critical concern of libraries and cultural heritage institutions. What do access, storage, and preservation mean for your institution? An awareness of institutional or collaborative goals is key to a successful DAMS implementation. Close

• 4. [Article] Analyzing Dam Feasibility in the Willamette River Watershed

  This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. ...

  Citation × Citation Citation Abstract Copy Title: Analyzing Dam Feasibility in the Willamette River Watershed Author: Nagel, Alexander Cameron Year: 2017 This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. Constructed between 1941 and 1969, these structures function in collaboration to comprise the Willamette River Basin Reservoir System (WRBRS). The motivation for this project derives from a growing awareness of the biophysical impacts that dam structures can have on riparian habitats. This project compares each of the 13 dams being assessed, to prioritize their level of utility within the system. The study takes the metrics from the top three services (flood regulation, hydropower generation and recreation) and disservices (fish mortality, structural risk and water temperature hazards) and creates a rubric that scores the feasibility of each dam within the system. Within a range between 0 to 3 for three dam services and 0 to -4.5 for two disservices, the overall calculated score elucidates for each structure whether its contribution to the WRBRS is positive or negative. Further analysis searches for spatiotemporal trends such as anomalous tributaries or magnified structural risk for structures exceeding a certain age. GIS data from the National Inventory of Dams (NID), U.S. Geologic Survey (USGS) water measurements, raw data from USACE, and peer-reviewed studies comprise the statistics that generate results for this analysis. The computed scores for each dam yield an average overall score of -1.31, and nine of the 13 structures have negative results, indicating that the WRBRS faces challenges going forward. The study seeks to contribute to the increasingly relevant examination of dam networks at the watershed scale. Title: Analyzing Dam Feasibility in the Willamette River Watershed Author: Nagel, Alexander Cameron Year: 2017 This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. Constructed between 1941 and 1969, these structures function in collaboration to comprise the Willamette River Basin Reservoir System (WRBRS). The motivation for this project derives from a growing awareness of the biophysical impacts that dam structures can have on riparian habitats. This project compares each of the 13 dams being assessed, to prioritize their level of utility within the system. The study takes the metrics from the top three services (flood regulation, hydropower generation and recreation) and disservices (fish mortality, structural risk and water temperature hazards) and creates a rubric that scores the feasibility of each dam within the system. Within a range between 0 to 3 for three dam services and 0 to -4.5 for two disservices, the overall calculated score elucidates for each structure whether its contribution to the WRBRS is positive or negative. Further analysis searches for spatiotemporal trends such as anomalous tributaries or magnified structural risk for structures exceeding a certain age. GIS data from the National Inventory of Dams (NID), U.S. Geologic Survey (USGS) water measurements, raw data from USACE, and peer-reviewed studies comprise the statistics that generate results for this analysis. The computed scores for each dam yield an average overall score of -1.31, and nine of the 13 structures have negative results, indicating that the WRBRS faces challenges going forward. The study seeks to contribute to the increasingly relevant examination of dam networks at the watershed scale. Close

• 5. [Article] Soil Development and Vegetation Response to Removal of a Small Dam, Lassen Volcanic National Park, California

  Dam removal is increasing as dams age, yet little is understood about the pedogenic response to dam removal. This study reports on the edaphic changes of reservoir sediments and vegetation cover one year ...

  Citation × Citation Citation Abstract Copy Title: Soil Development and Vegetation Response to Removal of a Small Dam, Lassen Volcanic National Park, California Author: Rohdy, Stephanie Kay Year: 2013 Dam removal is increasing as dams age, yet little is understood about the pedogenic response to dam removal. This study reports on the edaphic changes of reservoir sediments and vegetation cover one year following removal of a small earthen dam in Northern California. In August 2012, I sampled surface sediments from the former Dream Lake reservoir in Lassen Volcanic National Park, and compared their physical and chemical properties with soil samples from two reference sites. I also estimated percent cover of vegetation in the former reservoir and reference sites. My results show that the reservoir was under reduced conditions, as determined by gleyed soil color and a higher pH when compared to reference samples. In contrast to reservoirs on larger river systems which tend to be sinks for organic matter, Dream Lake showed a reduction in organic matter when compared to reference locations. My results suggest reservoirs created by dams cannot be considered to have similar sediment properties, namely increases in organic material. Unlike other studies that found former impoundments invaded by non-native species, the former Dream Lake site has been colonized by native grasses, sedges, and rushes. This study documents the edaphic properties and vegetation response of a small reservoir one year after dam removal, and suggests a more thorough investigation of those properties prior to undertaking costly restoration of these highly dynamic systems. Title: Soil Development and Vegetation Response to Removal of a Small Dam, Lassen Volcanic National Park, California Author: Rohdy, Stephanie Kay Year: 2013 Dam removal is increasing as dams age, yet little is understood about the pedogenic response to dam removal. This study reports on the edaphic changes of reservoir sediments and vegetation cover one year following removal of a small earthen dam in Northern California. In August 2012, I sampled surface sediments from the former Dream Lake reservoir in Lassen Volcanic National Park, and compared their physical and chemical properties with soil samples from two reference sites. I also estimated percent cover of vegetation in the former reservoir and reference sites. My results show that the reservoir was under reduced conditions, as determined by gleyed soil color and a higher pH when compared to reference samples. In contrast to reservoirs on larger river systems which tend to be sinks for organic matter, Dream Lake showed a reduction in organic matter when compared to reference locations. My results suggest reservoirs created by dams cannot be considered to have similar sediment properties, namely increases in organic material. Unlike other studies that found former impoundments invaded by non-native species, the former Dream Lake site has been colonized by native grasses, sedges, and rushes. This study documents the edaphic properties and vegetation response of a small reservoir one year after dam removal, and suggests a more thorough investigation of those properties prior to undertaking costly restoration of these highly dynamic systems. Close

• 6. [Article] Reservoir Evolution Following the Removal of Marmot Dam on the Sandy River, Oregon

  The October 2007 removal of Marmot Dam, a 14.3-m-tall dam on the Sandy River in northwestern Oregon storing approximately 730,000 m3 of impounded sediment, provided an opportunity to study short- and long-term ...

  Citation × Citation Citation Abstract Copy Title: Reservoir Evolution Following the Removal of Marmot Dam on the Sandy River, Oregon Author: Keith, Mackenzie Karli Year: 2012 The October 2007 removal of Marmot Dam, a 14.3-m-tall dam on the Sandy River in northwestern Oregon storing approximately 730,000 m3 of impounded sediment, provided an opportunity to study short- and long-term geomorphic effects of dam removal. Monitoring reservoir morphology during the two years following dam decommissioning yields a timeline of reservoir channel change. Comparison of a pre-dam survey in 1911 with post-removal surveys provides a basis from which to gage the Reservoir Reach evolution in the context of pre-dam conditions. Analyses of time-lapse photography, topographic surveys, and repeat LiDAR data sets provide detailed spatial and temporal documentation of a release of sediment from the reservoir following dam removal. The majority of morphologic changes to the reservoir largely took place during the first few days and weeks following removal. Channel incision and widening, along with gradient changes through the Reservoir Reach, exhibit diminishing changes with time. Channel incision rates of up to 13 m/hr and widening rates of up to 26 m/hr occurred within the first 24 hours following breaching of the coffer dam. Although channel position through the Reservoir Reach has remained relatively stable due to valley confinement, its width increased substantially. The channel reached an average width of 45 m within two weeks of breaching, but then erosion rates slowed and the channel width reached about 70 to 80 m after one and two years, respectively. Diminishing volumes of evacuated sediment were measured over time through quantitative analysis of survey datasets. About 15 percent of the initial impounded sediment was eroded from the Reservoir Reach within 60 hours of breaching; after one and two years, 50 and 58 percent was eroded, respectively. Grain-size analysis of terraces cut into reservoir fill following dam removal show that bed material coarsened over time at fixed elevations and vertically downward as the channel incised. Overall, these findings indicate valley morphology and local in-channel bedrock topography controlled the spatial distribution of sediment within the reservoir reach while variability in river discharge determined the timing of episodic sediment release. Changes within the Reservoir Reach shortly after dam removal and subsequent evolution over the two years following removal are likely attributable to 1) the timing and intensity of flow events, 2) the longitudinal and stratigraphic spatial variations in deposit grain-size distributions initially and over time, and 3) the pre-dam topography and existing valley morphology. Title: Reservoir Evolution Following the Removal of Marmot Dam on the Sandy River, Oregon Author: Keith, Mackenzie Karli Year: 2012 The October 2007 removal of Marmot Dam, a 14.3-m-tall dam on the Sandy River in northwestern Oregon storing approximately 730,000 m3 of impounded sediment, provided an opportunity to study short- and long-term geomorphic effects of dam removal. Monitoring reservoir morphology during the two years following dam decommissioning yields a timeline of reservoir channel change. Comparison of a pre-dam survey in 1911 with post-removal surveys provides a basis from which to gage the Reservoir Reach evolution in the context of pre-dam conditions. Analyses of time-lapse photography, topographic surveys, and repeat LiDAR data sets provide detailed spatial and temporal documentation of a release of sediment from the reservoir following dam removal. The majority of morphologic changes to the reservoir largely took place during the first few days and weeks following removal. Channel incision and widening, along with gradient changes through the Reservoir Reach, exhibit diminishing changes with time. Channel incision rates of up to 13 m/hr and widening rates of up to 26 m/hr occurred within the first 24 hours following breaching of the coffer dam. Although channel position through the Reservoir Reach has remained relatively stable due to valley confinement, its width increased substantially. The channel reached an average width of 45 m within two weeks of breaching, but then erosion rates slowed and the channel width reached about 70 to 80 m after one and two years, respectively. Diminishing volumes of evacuated sediment were measured over time through quantitative analysis of survey datasets. About 15 percent of the initial impounded sediment was eroded from the Reservoir Reach within 60 hours of breaching; after one and two years, 50 and 58 percent was eroded, respectively. Grain-size analysis of terraces cut into reservoir fill following dam removal show that bed material coarsened over time at fixed elevations and vertically downward as the channel incised. Overall, these findings indicate valley morphology and local in-channel bedrock topography controlled the spatial distribution of sediment within the reservoir reach while variability in river discharge determined the timing of episodic sediment release. Changes within the Reservoir Reach shortly after dam removal and subsequent evolution over the two years following removal are likely attributable to 1) the timing and intensity of flow events, 2) the longitudinal and stratigraphic spatial variations in deposit grain-size distributions initially and over time, and 3) the pre-dam topography and existing valley morphology. Close

• 7. [Article] Digital Asset Management System Assessment: Use Cases for Digital Infrastructure Re-design

  Academic libraries that offer digital asset management systems (DAMS) and services such as an institutional repository, data curation services, and digitization of historic documents face the need to assess ...

  Citation × Citation Citation Abstract Copy Title: Digital Asset Management System Assessment: Use Cases for Digital Infrastructure Re-design Author: Van Tuyl, Steve, Zhang, Hui, Whitmire, Amanda L. Year: 2015 Academic libraries that offer digital asset management systems (DAMS) and services such as an institutional repository, data curation services, and digitization of historic documents face the need to assess and refine services. This need can be most apparent when considering changes to DAMS infrastructure. The proposed panel presents the experiences of OSU Libraries and Press as we move to a new DAMS system for ScholarsArchive@OSU. Before considering DAMS platforms, we conducted an in-depth requirements analysis with our stakeholders, both within our organization as well as with stakeholders outside of the organization. The panelists will include OSU faculty and administrators selected for requirements interviews who present unique use cases for the DAMS, including those for whom the current iteration of the DAMS does not provide adequate service. Audience members will learn about using requirements analysis to design new digital infrastructures and will learn about popular digital library technologies (e.g. Hydra, DSpace). Title: Digital Asset Management System Assessment: Use Cases for Digital Infrastructure Re-design Author: Van Tuyl, Steve, Zhang, Hui, Whitmire, Amanda L. Year: 2015 Academic libraries that offer digital asset management systems (DAMS) and services such as an institutional repository, data curation services, and digitization of historic documents face the need to assess and refine services. This need can be most apparent when considering changes to DAMS infrastructure. The proposed panel presents the experiences of OSU Libraries and Press as we move to a new DAMS system for ScholarsArchive@OSU. Before considering DAMS platforms, we conducted an in-depth requirements analysis with our stakeholders, both within our organization as well as with stakeholders outside of the organization. The panelists will include OSU faculty and administrators selected for requirements interviews who present unique use cases for the DAMS, including those for whom the current iteration of the DAMS does not provide adequate service. Audience members will learn about using requirements analysis to design new digital infrastructures and will learn about popular digital library technologies (e.g. Hydra, DSpace). Close

• 8. [Article] Analysis and numerical simulation of the ground water system at the Bonneville navigation lock site, Oregon

  As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of ...

  Citation × Citation Citation Abstract Copy Title: Analysis and numerical simulation of the ground water system at the Bonneville navigation lock site, Oregon Author: Baron, Dirk Year: 1990 As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of the dam. It requires large quantities of water free from chemical and biological contamination. In addition, the water has to be in a narrow temperature range. Currently the fish hatchery receives its water from a well field that is located on the alluvial terrace downstream of Bonneville Dam. The well field lies in the proposed approach channel for the new lock and has to be abandoned during construction of the lock. For the continued water supply of the hatchery, a new well field will be developed north of the approach channel. Early in the planning phase for the new lock, concerns were raised about the potential impact of the relocation of the well field and the excavation of the new approach channel on the hatchery. To assess these concerns and to assure a continuous water supply during and after construction, a hydrogeologic investigation was initiated. Within the framework of the investigation this study focuses on the analysis of pumping test data and the development of a three-dimensional ground water flow model for the site. Title: Analysis and numerical simulation of the ground water system at the Bonneville navigation lock site, Oregon Author: Baron, Dirk Year: 1990 As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of the dam. It requires large quantities of water free from chemical and biological contamination. In addition, the water has to be in a narrow temperature range. Currently the fish hatchery receives its water from a well field that is located on the alluvial terrace downstream of Bonneville Dam. The well field lies in the proposed approach channel for the new lock and has to be abandoned during construction of the lock. For the continued water supply of the hatchery, a new well field will be developed north of the approach channel. Early in the planning phase for the new lock, concerns were raised about the potential impact of the relocation of the well field and the excavation of the new approach channel on the hatchery. To assess these concerns and to assure a continuous water supply during and after construction, a hydrogeologic investigation was initiated. Within the framework of the investigation this study focuses on the analysis of pumping test data and the development of a three-dimensional ground water flow model for the site. Close

• 9. [Article] An Analysis of Vegetation Recovery following Dam Removal at Hemlock Recreation Site, Washington

  Dam removals are becoming increasingly common as dams reach their life expectancy and face costly upgrades associated with relicensing. Though removal is often viewed as a success in terms of ecological ...

  Citation × Citation Citation Abstract Copy Title: An Analysis of Vegetation Recovery following Dam Removal at Hemlock Recreation Site, Washington Author: Ramsey, Greer Stewart Year: 2014 Dam removals are becoming increasingly common as dams reach their life expectancy and face costly upgrades associated with relicensing. Though removal is often viewed as a success in terms of ecological restoration, it also represents a major disturbance to an area. Previous research has shown that native species do not survive as well at these disturbed sites, and invasive species often dominate. This study examines the vegetation response in the drained reservoir area after the removal of Hemlock Dam on Trout Creek, a tributary to the Wind River in southern Washington. Transects were established and quadrats were sampled to determine the plant classifications and cover of vegetation and to examine possible correlations between environmental variables and the spatial distribution of plant classification groups. Sampling took place in the third and fourth years following dam removal, and the data was analyzed to determine significant changes and relationships. The results of this study showed that the site was dominated by a volunteer native forb Lotus purshianus (Spanish clover) and a planted native tree Alnus rubra (red alder). Most of the other species found were native volunteer forbs and grasses characteristic of early succession in this region. Both invasive species and planted species, with the exception of Alnus rubra, had low canopy covers. There was a significant increase in native plant canopy cover, as well as total canopy cover, from 2012 to 2013. There were also significant relationships between plant classification groups and environmental variables, including soil infiltration, elevation, and distance from stream. This study will help inform resource managers about the kinds of plants that will volunteer after dam removals and the possible success of re-vegetation projects. Title: An Analysis of Vegetation Recovery following Dam Removal at Hemlock Recreation Site, Washington Author: Ramsey, Greer Stewart Year: 2014 Dam removals are becoming increasingly common as dams reach their life expectancy and face costly upgrades associated with relicensing. Though removal is often viewed as a success in terms of ecological restoration, it also represents a major disturbance to an area. Previous research has shown that native species do not survive as well at these disturbed sites, and invasive species often dominate. This study examines the vegetation response in the drained reservoir area after the removal of Hemlock Dam on Trout Creek, a tributary to the Wind River in southern Washington. Transects were established and quadrats were sampled to determine the plant classifications and cover of vegetation and to examine possible correlations between environmental variables and the spatial distribution of plant classification groups. Sampling took place in the third and fourth years following dam removal, and the data was analyzed to determine significant changes and relationships. The results of this study showed that the site was dominated by a volunteer native forb Lotus purshianus (Spanish clover) and a planted native tree Alnus rubra (red alder). Most of the other species found were native volunteer forbs and grasses characteristic of early succession in this region. Both invasive species and planted species, with the exception of Alnus rubra, had low canopy covers. There was a significant increase in native plant canopy cover, as well as total canopy cover, from 2012 to 2013. There were also significant relationships between plant classification groups and environmental variables, including soil infiltration, elevation, and distance from stream. This study will help inform resource managers about the kinds of plants that will volunteer after dam removals and the possible success of re-vegetation projects. Close

• 10. [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