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• 21. [Image] Unsteady Flow and Fluid Transients

  	Citation × Citation Citation Abstract Copy Title: Unsteady Flow and Fluid Transients Year: 1992 Title: Unsteady Flow and Fluid Transients Year: 1992 Close

• 22. [Article] Funneled flow mechanisms in a sloping layered soil: Laboratory investigation

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

  Citation × Citation Citation Abstract Copy Title: Funneled flow mechanisms in a sloping layered soil: Laboratory investigation Author: Braddock, R. D., Selker, J. S., Steenhuis, T. S., Parlange, J.-Y., Kim, J.-S., Boll, J., Walter, M. T., Heilig, A. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Title: Funneled flow mechanisms in a sloping layered soil: Laboratory investigation Author: Braddock, R. D., Selker, J. S., Steenhuis, T. S., Parlange, J.-Y., Kim, J.-S., Boll, J., Walter, M. T., Heilig, A. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Close

• 23. [Article] Modeling Density Currents in Circular Clarifiers

  Design of sedimentation tanks for solid-liquid separation is often dependent on assuming ideal flow conditions. But the geometry of the tank and density currents as a result of temperature and suspended ...

  Citation × Citation Citation Abstract Copy Title: Modeling Density Currents in Circular Clarifiers Author: Wells, Scott A., LaLiberte, David M. Year: 1998 Design of sedimentation tanks for solid-liquid separation is often dependent on assuming ideal flow conditions. But the geometry of the tank and density currents as a result of temperature and suspended solids influences the fluid mechanics of the tank and can result in significant deviations from ideal flow. A two-dimensional radial flow model was proposed which incorporated the effect of density currents resulting from temperature and suspended solids differentials within the tank. The numerical model predicted the steady-state, layer-averaged radial flow and layer depth. The model solution and field data showed that the momentum and suspended solids of the inflow caused a density current that moved along the clarifier bottom. In the winter, this density current rose as a result of warm inflow water after the initial momentum had decreased and the suspended solids had settled. Title: Modeling Density Currents in Circular Clarifiers Author: Wells, Scott A., LaLiberte, David M. Year: 1998 Design of sedimentation tanks for solid-liquid separation is often dependent on assuming ideal flow conditions. But the geometry of the tank and density currents as a result of temperature and suspended solids influences the fluid mechanics of the tank and can result in significant deviations from ideal flow. A two-dimensional radial flow model was proposed which incorporated the effect of density currents resulting from temperature and suspended solids differentials within the tank. The numerical model predicted the steady-state, layer-averaged radial flow and layer depth. The model solution and field data showed that the momentum and suspended solids of the inflow caused a density current that moved along the clarifier bottom. In the winter, this density current rose as a result of warm inflow water after the initial momentum had decreased and the suspended solids had settled. Close

• 24. [Article] A Novel Approach to Flow Estimation in Tidal Rivers

  Reliable estimation of river discharge to the ocean from large tidal rivers is vital for water resources management and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, ...

  Citation × Citation Citation Abstract Copy Title: A Novel Approach to Flow Estimation in Tidal Rivers Author: Moftakhari Rostamkhani, Hamed, Jay, David A, Talke, Stefan A., Kukulka, Tobias, Bromirski, Peter D. Year: 2013 Reliable estimation of river discharge to the ocean from large tidal rivers is vital for water resources management and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, flow records are often limited in length and/or quality and tidal records often predate discharge records. Tidal theory indicates that tides and river discharge interact through quadratic bed friction, which diminishes and distorts the tidal wave as discharge increases. We use this phenomenon to develop a method of estimating river discharge for time periods with tidal data but no flow record. Employing sequential 32 day harmonic analyses of tidal properties, we calibrate San Francisco (SF), CA tide data to the Sacramento River delta outflow index from 1930 to 1990, and use the resulting relationship to hindcast river flow from 1858 to 1929. The M2 admittance (a ratio of the observed M2 tidal constituent to its astronomical forcing) best reproduces high flows, while low-flow periods are better represented by amplitude ratios based on higher harmonics (e.g.). Results show that the annual inflow to SF Bay is now 30% less than before 1900 and confirm that the flood of January 1862 was the largest since 1858. Title: A Novel Approach to Flow Estimation in Tidal Rivers Author: Moftakhari Rostamkhani, Hamed, Jay, David A, Talke, Stefan A., Kukulka, Tobias, Bromirski, Peter D. Year: 2013 Reliable estimation of river discharge to the ocean from large tidal rivers is vital for water resources management and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, flow records are often limited in length and/or quality and tidal records often predate discharge records. Tidal theory indicates that tides and river discharge interact through quadratic bed friction, which diminishes and distorts the tidal wave as discharge increases. We use this phenomenon to develop a method of estimating river discharge for time periods with tidal data but no flow record. Employing sequential 32 day harmonic analyses of tidal properties, we calibrate San Francisco (SF), CA tide data to the Sacramento River delta outflow index from 1930 to 1990, and use the resulting relationship to hindcast river flow from 1858 to 1929. The M2 admittance (a ratio of the observed M2 tidal constituent to its astronomical forcing) best reproduces high flows, while low-flow periods are better represented by amplitude ratios based on higher harmonics (e.g.). Results show that the annual inflow to SF Bay is now 30% less than before 1900 and confirm that the flood of January 1862 was the largest since 1858. Close

• 25. [Image] Jordan River Average Flows, 1985 - 1990 (Mcm/yr)

  	Citation × Citation Citation Abstract Copy Title: Jordan River Average Flows, 1985 - 1990 (Mcm/yr) Author: Naff, Thomas Year: 1991 Title: Jordan River Average Flows, 1985 - 1990 (Mcm/yr) Author: Naff, Thomas Year: 1991 Close

• 26. [Article] Subsurface flow of a forested riparian area in the Oregon coast range

  This study was undertaken to gain further understanding of the subsurface hydrology for a stream-adjacent riparian area in Western Oregon's Coast Range. Spatial and temporal fluctuations of the free water surface ...

  Citation × Citation Citation Abstract Copy Title: Subsurface flow of a forested riparian area in the Oregon coast range Author: Reiter, Maryanne This study was undertaken to gain further understanding of the subsurface hydrology for a stream-adjacent riparian area in Western Oregon's Coast Range. Spatial and temporal fluctuations of the free water surface of a toeslope, adjacent riparian area, and stream channel in a forested terrace reach were monitored over a period of one year. A total of 27 piezometers were installed (nine in each of three transects established perpendicular to the stream) in a stream-adjacent terrace and hillslope. These piezometers were monitored from September 26, 1989 to July 25, 1990. Results indicate that the direction of flow within a forested terrace can vary throughout the year. During the drier months of September and October, flow direction was generally towards the stream. However, by November the direction of flow for those areas closest to the stream had begun to change. In some cases the direction of flow changed up to 180° from the September direction. The location of influent/effluent zones along the stream (i.e., zones along the stream where the terrace has a lower or higher hydraulic head than the stream, respectively) also varied throughout the year. During October, 1989 the furthest upvalley stream-adjacent piezometer had hydraulic heads greater than the stream for the entire month, while two other stream adjacent piezometers did not. During normal precipitation in January, 1990 both furthest upvalley and the middle stream-adjacent piezometers had hydraulic heads greater than the stream for the entire month. By July, 1990 only the middle stream-adjacent piezometer had a hydraulic head greater than the stream for the entire month, while the furthest upvalley piezometer had a higher head for 33% of the month and the hydraulic head of furthest downvalley piezometer never exceeded that of the stream. For the Deer Creek study site, subsurface velocities were estimated to be in the range of 10-8 to 10-11 m/s resulting in a 3.8 year minimum travel time for storm water to reach the stream. Thus, soil matrix velocities using the Darcy equation were not sufficient to generate stormflow. However, no overland flow was observed during storm events, indicating that alternative subsurface flow pathways, such as macrochannels, are being utilized. Previous research has suggested that the release of water from terrace storage in small headwater streams is no.t sufficient to maintain baseflow. The results of the Deer Creek study support this conclusion. Furthermore, the results of this study indicate that forested riparian areas are hydrologically complex with respect to both space and time and that oversimplification of these systems may lead to misinterpretation of other processes associated with subsurface water dynamics. Title: Subsurface flow of a forested riparian area in the Oregon coast range Author: Reiter, Maryanne This study was undertaken to gain further understanding of the subsurface hydrology for a stream-adjacent riparian area in Western Oregon's Coast Range. Spatial and temporal fluctuations of the free water surface of a toeslope, adjacent riparian area, and stream channel in a forested terrace reach were monitored over a period of one year. A total of 27 piezometers were installed (nine in each of three transects established perpendicular to the stream) in a stream-adjacent terrace and hillslope. These piezometers were monitored from September 26, 1989 to July 25, 1990. Results indicate that the direction of flow within a forested terrace can vary throughout the year. During the drier months of September and October, flow direction was generally towards the stream. However, by November the direction of flow for those areas closest to the stream had begun to change. In some cases the direction of flow changed up to 180° from the September direction. The location of influent/effluent zones along the stream (i.e., zones along the stream where the terrace has a lower or higher hydraulic head than the stream, respectively) also varied throughout the year. During October, 1989 the furthest upvalley stream-adjacent piezometer had hydraulic heads greater than the stream for the entire month, while two other stream adjacent piezometers did not. During normal precipitation in January, 1990 both furthest upvalley and the middle stream-adjacent piezometers had hydraulic heads greater than the stream for the entire month. By July, 1990 only the middle stream-adjacent piezometer had a hydraulic head greater than the stream for the entire month, while the furthest upvalley piezometer had a higher head for 33% of the month and the hydraulic head of furthest downvalley piezometer never exceeded that of the stream. For the Deer Creek study site, subsurface velocities were estimated to be in the range of 10-8 to 10-11 m/s resulting in a 3.8 year minimum travel time for storm water to reach the stream. Thus, soil matrix velocities using the Darcy equation were not sufficient to generate stormflow. However, no overland flow was observed during storm events, indicating that alternative subsurface flow pathways, such as macrochannels, are being utilized. Previous research has suggested that the release of water from terrace storage in small headwater streams is no.t sufficient to maintain baseflow. The results of the Deer Creek study support this conclusion. Furthermore, the results of this study indicate that forested riparian areas are hydrologically complex with respect to both space and time and that oversimplification of these systems may lead to misinterpretation of other processes associated with subsurface water dynamics. Close

• 27. [Article] Will wetlands restoration plans today still be effective tomorrow? Evaluation of performance of potential wetlands for peak flow reduction in future climate scenarios in the Eagle Creek Watershed, IN

  Global climate change is expected to exaggerate the severity of floods and droughts and increase the frequency of extreme streamflow events in the Midwestern United States. Managing these projected impacts ...

  Citation × Citation Citation Abstract Copy Title: Will wetlands restoration plans today still be effective tomorrow? Evaluation of performance of potential wetlands for peak flow reduction in future climate scenarios in the Eagle Creek Watershed, IN Author: Walters, Kelli M. Global climate change is expected to exaggerate the severity of floods and droughts and increase the frequency of extreme streamflow events in the Midwestern United States. Managing these projected impacts poses a major challenge for water resources, conservation, and land use management. Wetlands have been considered as a conservation strategy and work to increase the capacity of watersheds by storing runoff upstream. The implementation of wetlands, especially in tile-drained agricultural watersheds, can reduce peak flows and help mitigate the anticipated impacts of climate change. The goal of this study was to evaluate the long-term performance of wetlands to reduce peak flows in future climate scenarios in the Eagle Creek Watershed in Indiana, as well as to establish a methodology to incorporate climate change into hydrological models to conduct better long-term land management studies and decisions. The Soil and Water Assessment Tool (SWAT) model was forced with bias corrected climate projections from the North American Regional Climate Change Assessment Program (NARCCAP) to evaluate the impacts of climate change on watershed hydrology and the ability of wetlands to reduce peak flows. Long-term monthly streamflow results predicted a slight increase in streamflow in the winter and a slight decrease in the summer from the past (1971-2000) to future (2041-2070) time periods. About half of the climate realizations produced an increase in the Q05 (5% exceedance flow) value and half a decrease, but all predictions agreed that high flow events will increase in frequency in the winter and decrease in the spring and summer. No-flow events, although found to be over-predicted by the hydrological model, showed an increase from the past to the future for all climate realizations. Results from the wetland analysis showed that if all potential wetlands identified in a previous study are installed in the watershed, maximum peak flow reductions of around 20-50 m³/s for the past and future, as well as decreased frequency of extreme events, can be seen. Wetlands proved to be a robust solution for peak flow reduction, producing consistent reductions across all climate projections for both the past and future time periods. Title: Will wetlands restoration plans today still be effective tomorrow? Evaluation of performance of potential wetlands for peak flow reduction in future climate scenarios in the Eagle Creek Watershed, IN Author: Walters, Kelli M. Global climate change is expected to exaggerate the severity of floods and droughts and increase the frequency of extreme streamflow events in the Midwestern United States. Managing these projected impacts poses a major challenge for water resources, conservation, and land use management. Wetlands have been considered as a conservation strategy and work to increase the capacity of watersheds by storing runoff upstream. The implementation of wetlands, especially in tile-drained agricultural watersheds, can reduce peak flows and help mitigate the anticipated impacts of climate change. The goal of this study was to evaluate the long-term performance of wetlands to reduce peak flows in future climate scenarios in the Eagle Creek Watershed in Indiana, as well as to establish a methodology to incorporate climate change into hydrological models to conduct better long-term land management studies and decisions. The Soil and Water Assessment Tool (SWAT) model was forced with bias corrected climate projections from the North American Regional Climate Change Assessment Program (NARCCAP) to evaluate the impacts of climate change on watershed hydrology and the ability of wetlands to reduce peak flows. Long-term monthly streamflow results predicted a slight increase in streamflow in the winter and a slight decrease in the summer from the past (1971-2000) to future (2041-2070) time periods. About half of the climate realizations produced an increase in the Q05 (5% exceedance flow) value and half a decrease, but all predictions agreed that high flow events will increase in frequency in the winter and decrease in the spring and summer. No-flow events, although found to be over-predicted by the hydrological model, showed an increase from the past to the future for all climate realizations. Results from the wetland analysis showed that if all potential wetlands identified in a previous study are installed in the watershed, maximum peak flow reductions of around 20-50 m³/s for the past and future, as well as decreased frequency of extreme events, can be seen. Wetlands proved to be a robust solution for peak flow reduction, producing consistent reductions across all climate projections for both the past and future time periods. Close

• 28. [Article] Amaila Falls Hydroelectric Project Model Development and Scenarios

  The focus of this present study is to perform the following tasks: * Develop a hydrodynamic and water quality model of the reservoir formed by the Amaila Falls Hydroelectric Project * Develop and run modeling ...

  Citation × Citation Citation Abstract Copy Title: Amaila Falls Hydroelectric Project Model Development and Scenarios Author: Berger, Chris, Wells, Scott A., Wells, Vanessa Year: 2010 The focus of this present study is to perform the following tasks: * Develop a hydrodynamic and water quality model of the reservoir formed by the Amaila Falls Hydroelectric Project * Develop and run modeling scenarios Water quality model simulations of the 23.3 km2 reservoir for Amaila Falls Hydroelectric Project were conducted for low, average, and high flow years. A scenario with no vegetation removed from the reservoir for an average flow was also simulated. Conditions downstream of the reservoir were also modeled using a river model. The model used for the reservoir formed by Amaila Falls Hydroelectric Project is the public domain model, CE-QUAL-W2. Title: Amaila Falls Hydroelectric Project Model Development and Scenarios Author: Berger, Chris, Wells, Scott A., Wells, Vanessa Year: 2010 The focus of this present study is to perform the following tasks: * Develop a hydrodynamic and water quality model of the reservoir formed by the Amaila Falls Hydroelectric Project * Develop and run modeling scenarios Water quality model simulations of the 23.3 km2 reservoir for Amaila Falls Hydroelectric Project were conducted for low, average, and high flow years. A scenario with no vegetation removed from the reservoir for an average flow was also simulated. Conditions downstream of the reservoir were also modeled using a river model. The model used for the reservoir formed by Amaila Falls Hydroelectric Project is the public domain model, CE-QUAL-W2. Close

• 29. [Image] Flows in the Lower Jordan River 1985-1990

  	Citation × Citation Citation Abstract Copy Title: Flows in the Lower Jordan River 1985-1990 Author: Naff, Thomas Year: 2008 Title: Flows in the Lower Jordan River 1985-1990 Author: Naff, Thomas Year: 2008 Close

• 30. [Image] Israeli Withdrawals from Yarmuk River Flows at Lake Tiberias Bank

  	Citation × Citation Citation Abstract Copy Title: Israeli Withdrawals from Yarmuk River Flows at Lake Tiberias Bank Year: 2011 Title: Israeli Withdrawals from Yarmuk River Flows at Lake Tiberias Bank Year: 2011 Close