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• 1. [Article] Watershed Data Organization and Project Prioritization

  The Oregon Coastal Salmon Restoration Initiative (OCSRI) (1197) is the first of several documents that have come to be known as the Oregon Plan for Salmon and watersheds (OPSW). The OCSRI indicates that ...

  Citation × Citation Citation Abstract Copy Title: Watershed Data Organization and Project Prioritization Author: Darling, Joshua Year: 2003 The Oregon Coastal Salmon Restoration Initiative (OCSRI) (1197) is the first of several documents that have come to be known as the Oregon Plan for Salmon and watersheds (OPSW). The OCSRI indicates that protection and restoration of salmonid stocks and improvement in water quality are the main roles for state agencies within the Oregon Plan (EO09-01: 1(b)). The Oregon Plan specifies particular actions that state agencies must take to aid in salmon recovery and also directs the Governors Watershed Enhancement Board (GWEB) to help create and organize watershed councils responsible for assessing conditions and determining priorities for watershed health. Title: Watershed Data Organization and Project Prioritization Author: Darling, Joshua Year: 2003 The Oregon Coastal Salmon Restoration Initiative (OCSRI) (1197) is the first of several documents that have come to be known as the Oregon Plan for Salmon and watersheds (OPSW). The OCSRI indicates that protection and restoration of salmonid stocks and improvement in water quality are the main roles for state agencies within the Oregon Plan (EO09-01: 1(b)). The Oregon Plan specifies particular actions that state agencies must take to aid in salmon recovery and also directs the Governors Watershed Enhancement Board (GWEB) to help create and organize watershed councils responsible for assessing conditions and determining priorities for watershed health. Close

• 2. [Article] Watershed Solutions: Collaborative Problem Solving for States and Communities

  In July 2002, the National Policy Consensus Center (NPCC) hosted a colloquium for people involved in watershed collaborations, academics, and other experts from government and non-profit organizations. ...

  Citation × Citation Citation Abstract Copy Title: Watershed Solutions: Collaborative Problem Solving for States and Communities Author: National Policy Consensus Center Year: 2002 In July 2002, the National Policy Consensus Center (NPCC) hosted a colloquium for people involved in watershed collaborations, academics, and other experts from government and non-profit organizations. Its aim was to identify lessons learned from successful watershed initiatives, and to develop recommendations for governors and other state officials on ways to enhance the use and effectiveness of watershed partnerships. This report is an outgrowth of that conference. Studies on watershed collaborations are beginning to identify what makes them successful and what some of the barriers are to greater success. For example, contrary to the fears of some observers, successful collaborations do not shy away from controversial issues. Drawing on a growing list of best practices and lessons learned from experiences across the country, state officials and local partners can be better assured of successful outcomes in collaborative watershed management initiatives. Title: Watershed Solutions: Collaborative Problem Solving for States and Communities Author: National Policy Consensus Center Year: 2002 In July 2002, the National Policy Consensus Center (NPCC) hosted a colloquium for people involved in watershed collaborations, academics, and other experts from government and non-profit organizations. Its aim was to identify lessons learned from successful watershed initiatives, and to develop recommendations for governors and other state officials on ways to enhance the use and effectiveness of watershed partnerships. This report is an outgrowth of that conference. Studies on watershed collaborations are beginning to identify what makes them successful and what some of the barriers are to greater success. For example, contrary to the fears of some observers, successful collaborations do not shy away from controversial issues. Drawing on a growing list of best practices and lessons learned from experiences across the country, state officials and local partners can be better assured of successful outcomes in collaborative watershed management initiatives. Close

• 3. [Article] Type and Timing of Stream Flow Changes in Urbanizing Watersheds in the Eastern U.S.

  Linking the type and timing of hydrologic changes with patterns of urban growth is essential to identifying the underlying mechanisms that drive declines in urban aquatic ecosystems. In six urbanizing ...

  Citation × Citation Citation Abstract Copy Title: Type and Timing of Stream Flow Changes in Urbanizing Watersheds in the Eastern U.S. Author: Hopkins, Kristina G., Morse, Nathaniel B., Bain, Daniel J., Bettez, Neil D., Grimm, Nancy B., Morse, Jennifer L., Palta, Monica M. Year: 2015 Linking the type and timing of hydrologic changes with patterns of urban growth is essential to identifying the underlying mechanisms that drive declines in urban aquatic ecosystems. In six urbanizing watersheds surrounding three U.S. cities (Baltimore, MD, Boston, MA, and Pittsburgh, PA), we reconstructed the history of development patterns since 1900 and assessed the magnitude and timing of stream flow changes during watershed development. Development reconstructions indicated that the majority of watershed development occurred during a period of peak population growth, typically between 1950 and 1970. Stream flow records indicated significant increases in annual frequency of high-flow events in all six watersheds and increases in annual runoff efficiency in five watersheds. Annual development intensity during the peak growth period had the strongest association with the magnitude of changes in high-flow frequency from the pre- to post-development periods. Results suggest the timing of the peak growth period is particularly important to understanding hydrologic changes, because it can set the type of stormwater infrastructure installed within a watershed. In three watersheds there was a rapid (~10-15 years) shift toward more frequent high-flow events, and in four watersheds there was a shift toward higher runoff efficiency. Breakpoint analyses indicated these shifts occurred between 1969 and 1976 for high-flow frequency and between 1962 and 1984 for runoff efficiency. Results indicated that the timing of high-flow changes were mainly driven by the development trajectory of each watershed, whereas the timing of runoff-efficiency changes were driven by a combination of development trajectories and extreme weather events. Our results underscore the need to refine the causes of urban stream degradation to incorporate the impact of gradual versus rapid urbanization on hydrologic changes and aquatic ecosystem function, as well as to recognize that the dominant drivers of hydrologic changes are heterogeneous among urban watersheds and vary over time. Title: Type and Timing of Stream Flow Changes in Urbanizing Watersheds in the Eastern U.S. Author: Hopkins, Kristina G., Morse, Nathaniel B., Bain, Daniel J., Bettez, Neil D., Grimm, Nancy B., Morse, Jennifer L., Palta, Monica M. Year: 2015 Linking the type and timing of hydrologic changes with patterns of urban growth is essential to identifying the underlying mechanisms that drive declines in urban aquatic ecosystems. In six urbanizing watersheds surrounding three U.S. cities (Baltimore, MD, Boston, MA, and Pittsburgh, PA), we reconstructed the history of development patterns since 1900 and assessed the magnitude and timing of stream flow changes during watershed development. Development reconstructions indicated that the majority of watershed development occurred during a period of peak population growth, typically between 1950 and 1970. Stream flow records indicated significant increases in annual frequency of high-flow events in all six watersheds and increases in annual runoff efficiency in five watersheds. Annual development intensity during the peak growth period had the strongest association with the magnitude of changes in high-flow frequency from the pre- to post-development periods. Results suggest the timing of the peak growth period is particularly important to understanding hydrologic changes, because it can set the type of stormwater infrastructure installed within a watershed. In three watersheds there was a rapid (~10-15 years) shift toward more frequent high-flow events, and in four watersheds there was a shift toward higher runoff efficiency. Breakpoint analyses indicated these shifts occurred between 1969 and 1976 for high-flow frequency and between 1962 and 1984 for runoff efficiency. Results indicated that the timing of high-flow changes were mainly driven by the development trajectory of each watershed, whereas the timing of runoff-efficiency changes were driven by a combination of development trajectories and extreme weather events. Our results underscore the need to refine the causes of urban stream degradation to incorporate the impact of gradual versus rapid urbanization on hydrologic changes and aquatic ecosystem function, as well as to recognize that the dominant drivers of hydrologic changes are heterogeneous among urban watersheds and vary over time. Close

• 4. [Article] Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend

  We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based ...

  Citation × Citation Citation Abstract Copy Title: Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend Author: Miller, Stephanie A., Gordon, Sean N, Eldred, Peter, Beloin, Ronald M., Wilcox, Steve, Raggon, Mark, Andersen, Heidi, Muldoon, Ariel Year: 2015 We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based on stream sampling data collected from 2002 to the 2013 (214 watersheds) as part of an eight year repeating (rotating) sample design. We are currently halfway through our second rotation of stream sampling, and have repeated 110 watersheds since the second rotation began in 2009. The analysis presented in this report uses roughly half the number of watersheds as was originally intended by the sample design since re-visitation will not be completed until 2017. In the meantime, we compare the first rotation of visits (2002-2009) to the first four years of the second rotation (2010-2013) giving us a general idea of current patterns. To evaluate stream condition we used a reference condition nearest neighbor statistical approach to calculate the stream physical habitat scores based on substrate, wood, and pool metrics for each watershed. Macroinvertebrates and water temperature were analyzed separately from physical habitat and provide additional assessment of overall watershed condition. Scores for both stream and upslope/riparian conditions were normalized to fall between 0 (poor) and 100 (good). Title: Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend Author: Miller, Stephanie A., Gordon, Sean N, Eldred, Peter, Beloin, Ronald M., Wilcox, Steve, Raggon, Mark, Andersen, Heidi, Muldoon, Ariel Year: 2015 We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based on stream sampling data collected from 2002 to the 2013 (214 watersheds) as part of an eight year repeating (rotating) sample design. We are currently halfway through our second rotation of stream sampling, and have repeated 110 watersheds since the second rotation began in 2009. The analysis presented in this report uses roughly half the number of watersheds as was originally intended by the sample design since re-visitation will not be completed until 2017. In the meantime, we compare the first rotation of visits (2002-2009) to the first four years of the second rotation (2010-2013) giving us a general idea of current patterns. To evaluate stream condition we used a reference condition nearest neighbor statistical approach to calculate the stream physical habitat scores based on substrate, wood, and pool metrics for each watershed. Macroinvertebrates and water temperature were analyzed separately from physical habitat and provide additional assessment of overall watershed condition. Scores for both stream and upslope/riparian conditions were normalized to fall between 0 (poor) and 100 (good). Close

• 5. [Article] Urbanization and its Relationship to Water Quality within the Bronson Creek Watershed

  Urbanization and its Relationship to Water Quality within the Bronson Creek Watershed A watershed analysis project was undertaken to investigate the impact of urbanization on the water quality with Bronson ...

  Citation × Citation Citation Abstract Copy Title: Urbanization and its Relationship to Water Quality within the Bronson Creek Watershed Author: Creech, Jason Cristopher Year: 2003 Urbanization and its Relationship to Water Quality within the Bronson Creek Watershed A watershed analysis project was undertaken to investigate the impact of urbanization on the water quality with Bronson Creek; a small urban stream in the metropolitan area of Portland, Oregon. Total Maximum Daily Loads (TMDLs) have been established for several water quality parameters within the watershed. Water quality data were collected at nine sampling along Bronson Creek by Clean Water Services, a local public utility charged with storm water management and water quality protection duties. Only seven water quality parameters were included in the analysis; they were 1) temperature, 2) total phosphorous, 3) ortho-phosphate, 4) ammonia, 5) total nitrogen, 6) total suspended solids, and 7) E. Coli. Samples were taken approximately twice a month over a 7 year period from 1994 – 2001. Total impervious area (TIA) was used as the indicator of urbanization for the project. Impervious area values (TIA%) were calculated by digitizing aerial photography. Yearly TIA values were calculated for the entire watershed, as well as for its 37 subasins (subcatchement level). Water quality data were analyzed for variations along the stream and for the presence of trends (monotonic changes over time) during seasons of poor water quality. Kendall’s t was also used as the trend test statistic. Data were also analyzed to determine if an association exists between water quality at a sampling site and the upstream imperviousness (TIA%). Kendall’s t was used as the test statistic. Negative trends (improving water quality) were found throughout the watershed with nitrogen exhibiting the largest reduction. Temperature was the only parameter not to exhibit a negative trend at any location within the watershed. Results of the correlation between water quality and TIA% showed similar results, where a parameter experiencing a trend also exhibited a significant Kendall’s correlation with upstream TIA%. As TIA increased, water quality improved at least one site, for all parameters except temperature. One possible cause of the improving water quality within Bronson Creek is the implementation of best management practices within the watershed. Stormwater ponds were located in subcatchments that were adjacent to water quality sampling sites with improving water quality. The Bronson Creek watershed is also part of a pilot program to test the effectiveness of best management practices on improving water quality in the urban environment. Title: Urbanization and its Relationship to Water Quality within the Bronson Creek Watershed Author: Creech, Jason Cristopher Year: 2003 Urbanization and its Relationship to Water Quality within the Bronson Creek Watershed A watershed analysis project was undertaken to investigate the impact of urbanization on the water quality with Bronson Creek; a small urban stream in the metropolitan area of Portland, Oregon. Total Maximum Daily Loads (TMDLs) have been established for several water quality parameters within the watershed. Water quality data were collected at nine sampling along Bronson Creek by Clean Water Services, a local public utility charged with storm water management and water quality protection duties. Only seven water quality parameters were included in the analysis; they were 1) temperature, 2) total phosphorous, 3) ortho-phosphate, 4) ammonia, 5) total nitrogen, 6) total suspended solids, and 7) E. Coli. Samples were taken approximately twice a month over a 7 year period from 1994 – 2001. Total impervious area (TIA) was used as the indicator of urbanization for the project. Impervious area values (TIA%) were calculated by digitizing aerial photography. Yearly TIA values were calculated for the entire watershed, as well as for its 37 subasins (subcatchement level). Water quality data were analyzed for variations along the stream and for the presence of trends (monotonic changes over time) during seasons of poor water quality. Kendall’s t was also used as the trend test statistic. Data were also analyzed to determine if an association exists between water quality at a sampling site and the upstream imperviousness (TIA%). Kendall’s t was used as the test statistic. Negative trends (improving water quality) were found throughout the watershed with nitrogen exhibiting the largest reduction. Temperature was the only parameter not to exhibit a negative trend at any location within the watershed. Results of the correlation between water quality and TIA% showed similar results, where a parameter experiencing a trend also exhibited a significant Kendall’s correlation with upstream TIA%. As TIA increased, water quality improved at least one site, for all parameters except temperature. One possible cause of the improving water quality within Bronson Creek is the implementation of best management practices within the watershed. Stormwater ponds were located in subcatchments that were adjacent to water quality sampling sites with improving water quality. The Bronson Creek watershed is also part of a pilot program to test the effectiveness of best management practices on improving water quality in the urban environment. Close

• 6. [Article] Factors of Successful Collaboration: Oregon's Watershed Councils as Collaborative Systems

  The public sector, business professionals and organization leaders are among some of the diverse entities increasingly viewing collaboration as a useful, and at times necessary, practice. Collaborative ...

  Citation × Citation Citation Abstract Copy Title: Factors of Successful Collaboration: Oregon's Watershed Councils as Collaborative Systems Author: Doherty, Meghan, National Policy Consensus Center Year: 2015 The public sector, business professionals and organization leaders are among some of the diverse entities increasingly viewing collaboration as a useful, and at times necessary, practice. Collaborative systems are networks formed by individuals who repeatedly interact over long time horizons to solve problems and achieve goals they could not on their own. Throughout the academic literature, there are many references to and definitions of collaborative systems or networks, as well as various opinions on what factors enable these systems to be successful. However, these are usually context-specific or limited to the perspective of a certain discipline. Furthermore, empirical literature usually hones in on collaborative projects; networks working together within a predetermined timeframe and towards a specific desired outcome. This research had two objectives. The first was to identify the common factors effecting collaborative performance and possible collaboration benefits from the various academic disciplines and use them to develop a construct for collaborative systems. The project then utilized the rich history of Oregon’s watershed councils as a case study and applied this construct to their boards as they represent a diverse set of collaborative groups that have been in operation for over twenty years. This research measured the identified factors effecting collaborative performance and compared them to the benefits received through a combination of survey questions and outside research, resulting in averaged “factor” and “benefit” scores across all responses as well as for four case study watershed councils. The final step was to use regression analysis to understand the relationship between the factors and collaboration benefits This research developed and tested a construct for collaborative systems by identifying commonly cited factors across varied academic disciples. Through application to Oregon’s watershed councils, this research acquired preliminary data in order to identify the positive relationship between factors and benefits. In addition, it identified opportunities for enhancing watershed council collaborative performance by ranking these factor scores. Further research is needed to expand the application of these findings, as well as to test these factors in other collaborative systems. Title: Factors of Successful Collaboration: Oregon's Watershed Councils as Collaborative Systems Author: Doherty, Meghan, National Policy Consensus Center Year: 2015 The public sector, business professionals and organization leaders are among some of the diverse entities increasingly viewing collaboration as a useful, and at times necessary, practice. Collaborative systems are networks formed by individuals who repeatedly interact over long time horizons to solve problems and achieve goals they could not on their own. Throughout the academic literature, there are many references to and definitions of collaborative systems or networks, as well as various opinions on what factors enable these systems to be successful. However, these are usually context-specific or limited to the perspective of a certain discipline. Furthermore, empirical literature usually hones in on collaborative projects; networks working together within a predetermined timeframe and towards a specific desired outcome. This research had two objectives. The first was to identify the common factors effecting collaborative performance and possible collaboration benefits from the various academic disciplines and use them to develop a construct for collaborative systems. The project then utilized the rich history of Oregon’s watershed councils as a case study and applied this construct to their boards as they represent a diverse set of collaborative groups that have been in operation for over twenty years. This research measured the identified factors effecting collaborative performance and compared them to the benefits received through a combination of survey questions and outside research, resulting in averaged “factor” and “benefit” scores across all responses as well as for four case study watershed councils. The final step was to use regression analysis to understand the relationship between the factors and collaboration benefits This research developed and tested a construct for collaborative systems by identifying commonly cited factors across varied academic disciples. Through application to Oregon’s watershed councils, this research acquired preliminary data in order to identify the positive relationship between factors and benefits. In addition, it identified opportunities for enhancing watershed council collaborative performance by ranking these factor scores. Further research is needed to expand the application of these findings, as well as to test these factors in other collaborative systems. Close

• 7. [Article] Getting Salmon Back in Salmon Creek: Systematizing Comparative Water Quality Analysis for Targeted Restoration

  This presentation focuses on water quality restoration efforts in Salmon Creek

  Citation × Citation Citation Abstract Copy Title: Getting Salmon Back in Salmon Creek: Systematizing Comparative Water Quality Analysis for Targeted Restoration Author: Grabowski, Zbigniew J., Janjua, Sarah, Swamer, Michael, Chang, Heejun, Watson, Eric Year: 2013 This presentation focuses on water quality restoration efforts in Salmon Creek Title: Getting Salmon Back in Salmon Creek: Systematizing Comparative Water Quality Analysis for Targeted Restoration Author: Grabowski, Zbigniew J., Janjua, Sarah, Swamer, Michael, Chang, Heejun, Watson, Eric Year: 2013 This presentation focuses on water quality restoration efforts in Salmon Creek Close

• 8. [Article] Vegetation, Environmental Characteristics, and their Relationships: Variation within the Annually Flooded Riparian Zones of the John Day River Basin, Oregon

  I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships ...

  Citation × Citation Citation Abstract Copy Title: Vegetation, Environmental Characteristics, and their Relationships: Variation within the Annually Flooded Riparian Zones of the John Day River Basin, Oregon Author: Hartsfield, Samuel J. Year: 2009 I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships between species and environmental variables would display differences between these two zones. Vegetation, environmental variables, and relationships between them were assessed for the entire annually flooded riparian zone, and for the proposed upper and lower zones. Data were collected from 60 one-square-meter quadrats: 30 in each the upper and lower zones. Sites were randomly selected and located so that flood duration was roughly equal at all sites within each zone. 34 plant species were encountered: 25 in the upper zone, 27 in the lower zone. Wetland obligate and facultative wetland species groups and eight individual species accounted for statistically different percentages ofquadrat cover between zones. ANOSIM analysis identified two statistically distinct vegetation communities between the two zones. Soil texture averaged 75.85% sand and 20.81% fines. Sand ranged between 36.69% and 95.55%. Fines ranged between 2.54% and 58.84%. A horizon depths and fine soil particle concentrations were greater in the upper zone. Coarser soils with more sand and gravel dominated the lower zone. All enviromnental variables studied, except pH, were highly variable throughout the study area. ANOSIM analysis results suggest that the upper and lower zones have distinct, statistically different physical environments from each other. Regression analyses relating species quadrat cover to physical environmental variables were performed for the total, upper, and lower riparian zones. Numerous differences were identified between the upper and lower riparian zones that the riparian scale analyses did not represent accurately. There were ten instances in which the zone scale analyses identified a relationship in either the upper or lower zone, while the corresponding riparian scale analysis failed to identify any relationship. The results of this study indicate that vegetation and the physical environment are statistically different between the upper and lower zones on this river, and that relationships between a given plant species and environmental variable can vary between zones. Future research and management efforts should consider and address the potential for such between-zone variation. Title: Vegetation, Environmental Characteristics, and their Relationships: Variation within the Annually Flooded Riparian Zones of the John Day River Basin, Oregon Author: Hartsfield, Samuel J. Year: 2009 I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships between species and environmental variables would display differences between these two zones. Vegetation, environmental variables, and relationships between them were assessed for the entire annually flooded riparian zone, and for the proposed upper and lower zones. Data were collected from 60 one-square-meter quadrats: 30 in each the upper and lower zones. Sites were randomly selected and located so that flood duration was roughly equal at all sites within each zone. 34 plant species were encountered: 25 in the upper zone, 27 in the lower zone. Wetland obligate and facultative wetland species groups and eight individual species accounted for statistically different percentages ofquadrat cover between zones. ANOSIM analysis identified two statistically distinct vegetation communities between the two zones. Soil texture averaged 75.85% sand and 20.81% fines. Sand ranged between 36.69% and 95.55%. Fines ranged between 2.54% and 58.84%. A horizon depths and fine soil particle concentrations were greater in the upper zone. Coarser soils with more sand and gravel dominated the lower zone. All enviromnental variables studied, except pH, were highly variable throughout the study area. ANOSIM analysis results suggest that the upper and lower zones have distinct, statistically different physical environments from each other. Regression analyses relating species quadrat cover to physical environmental variables were performed for the total, upper, and lower riparian zones. Numerous differences were identified between the upper and lower riparian zones that the riparian scale analyses did not represent accurately. There were ten instances in which the zone scale analyses identified a relationship in either the upper or lower zone, while the corresponding riparian scale analysis failed to identify any relationship. The results of this study indicate that vegetation and the physical environment are statistically different between the upper and lower zones on this river, and that relationships between a given plant species and environmental variable can vary between zones. Future research and management efforts should consider and address the potential for such between-zone variation. Close

• 9. [Article] Effects of Tide Gate Replacement on Water Temperature ina Freshwater Slough in the Columbia River Estuary

  Dramatic declines in salmon populations in the Pacific Northwest have brought new attention to the importance of estuarine rearing habitats. Levees and tide gates used to convert estuarine wetlands into ...

  Citation × Citation Citation Abstract Copy Title: Effects of Tide Gate Replacement on Water Temperature ina Freshwater Slough in the Columbia River Estuary Author: Ennis, Sara Year: 2009 Dramatic declines in salmon populations in the Pacific Northwest have brought new attention to the importance of estuarine rearing habitats. Levees and tide gates used to convert estuarine wetlands into farmland have reduced available habitat by more than half of historical levels. Recent efforts to restore estuarine habitats include tide gate replacement, though this method has been poorly studied. As a key indicator of salmon habitat suitability, temperature was used to evaluate the effects of tide gate replacement in a tidally influenced freshwater slough in the Lower Columbia River estuary. Three tide gates in the largest slough on Tenasillahe Island were replaced in 2007 with side-hinged aluminum gates. As managed during the data collection periods, the new tide gates did not allow tidal inflow into the slough. The study employed a Before-After, Control-Impact (BACI) approach, collecting data seasonally two years before and after replacement at the impact site and at the control site, a relatively unaltered slough on nearby Welch Island. Randomized Intervention Analysis and Monte Carlo tests revealed no significant difference in slough water temperatures after tide gate replacement, although minimum temperatures dropped up and downstream of the tide gates. Although the new tide gates did not have a significant effect on water temperature, the lower minimum temperatures may have been caused by a slight increase in tidal circulation. This result suggests that slough temperatures would decrease if the tide gates were managed to increase tidal inflow, and thus improve the quality of salmon rearing habitat. Title: Effects of Tide Gate Replacement on Water Temperature ina Freshwater Slough in the Columbia River Estuary Author: Ennis, Sara Year: 2009 Dramatic declines in salmon populations in the Pacific Northwest have brought new attention to the importance of estuarine rearing habitats. Levees and tide gates used to convert estuarine wetlands into farmland have reduced available habitat by more than half of historical levels. Recent efforts to restore estuarine habitats include tide gate replacement, though this method has been poorly studied. As a key indicator of salmon habitat suitability, temperature was used to evaluate the effects of tide gate replacement in a tidally influenced freshwater slough in the Lower Columbia River estuary. Three tide gates in the largest slough on Tenasillahe Island were replaced in 2007 with side-hinged aluminum gates. As managed during the data collection periods, the new tide gates did not allow tidal inflow into the slough. The study employed a Before-After, Control-Impact (BACI) approach, collecting data seasonally two years before and after replacement at the impact site and at the control site, a relatively unaltered slough on nearby Welch Island. Randomized Intervention Analysis and Monte Carlo tests revealed no significant difference in slough water temperatures after tide gate replacement, although minimum temperatures dropped up and downstream of the tide gates. Although the new tide gates did not have a significant effect on water temperature, the lower minimum temperatures may have been caused by a slight increase in tidal circulation. This result suggests that slough temperatures would decrease if the tide gates were managed to increase tidal inflow, and thus improve the quality of salmon rearing habitat. Close

• 10. [Article] Effects of Water Development on Arid Land Freshwater Ecosystems

  This presentation focuses on the Columbia Basin Project

  Citation × Citation Citation Abstract Copy Title: Effects of Water Development on Arid Land Freshwater Ecosystems Author: Strecker, Angela L. Year: 2013 This presentation focuses on the Columbia Basin Project Title: Effects of Water Development on Arid Land Freshwater Ecosystems Author: Strecker, Angela L. Year: 2013 This presentation focuses on the Columbia Basin Project Close