Search

Search Results

• 61. [Article] Validation of an ANN Flow Prediction Model Using a Multt-Station Cluster Analysis

  The objective of this study is to validate a flow prediction model for a hydrometric station using a multistation criterion in addition to standard single-station performance criteria. In this contribution ...

  Citation × Citation Citation Abstract Copy Title: Validation of an ANN Flow Prediction Model Using a Multt-Station Cluster Analysis Author: Demirel, Mehmet, Booij, Martijn, Kahya, Ercan Year: 2012 The objective of this study is to validate a flow prediction model for a hydrometric station using a multistation criterion in addition to standard single-station performance criteria. In this contribution we used cluster analysis to identify the regional flow height, i.e., water-level patterns and validate the output of an artificial neural network (ANN) model of the Alportel River in Portugal. Measurements of precipitation, temperature, and flow height were used as input variables to the ANN model with a lead time of 12 h. The lead time of 12 h is assumed to be appropriate for a short-term hydrological prediction since it is meaningful for physical processes. The ANN model with three inputs, four hidden neurons, and ten epochs was tested using the new model-validation criterion. The high performance of the model (i.e., Nash-Sutcliffe coefficient is equal to 0.922) was confirmed by the cluster-analysis criterion. It can be concluded that a multistation-based approach can be used as an additional validation criterion and might result in a rejection of a model which initially passed a single-station validation criterion. Title: Validation of an ANN Flow Prediction Model Using a Multt-Station Cluster Analysis Author: Demirel, Mehmet, Booij, Martijn, Kahya, Ercan Year: 2012 The objective of this study is to validate a flow prediction model for a hydrometric station using a multistation criterion in addition to standard single-station performance criteria. In this contribution we used cluster analysis to identify the regional flow height, i.e., water-level patterns and validate the output of an artificial neural network (ANN) model of the Alportel River in Portugal. Measurements of precipitation, temperature, and flow height were used as input variables to the ANN model with a lead time of 12 h. The lead time of 12 h is assumed to be appropriate for a short-term hydrological prediction since it is meaningful for physical processes. The ANN model with three inputs, four hidden neurons, and ten epochs was tested using the new model-validation criterion. The high performance of the model (i.e., Nash-Sutcliffe coefficient is equal to 0.922) was confirmed by the cluster-analysis criterion. It can be concluded that a multistation-based approach can be used as an additional validation criterion and might result in a rejection of a model which initially passed a single-station validation criterion. Close

• 62. [Article] Mapping the Distribution of Vesicular Textures on Silicic Lavas Using the Thermal Infrared Multispectral Scanner

  The Thermal Infrared Multispectral Scanner (TlMS) is a potentially powerful tool for mapping detailed chemical variations in silicic lava flows which in turn could expand knowledge of pre-eruption compositional ...

  Citation × Citation Citation Abstract Copy Title: Mapping the Distribution of Vesicular Textures on Silicic Lavas Using the Thermal Infrared Multispectral Scanner Author: Ondrusek, Jaime, Christensen, Philip R., Fink, Jonathan Year: 1993 The Thermal Infrared Multispectral Scanner (TlMS) is a potentially powerful tool for mapping detailed chemical variations in silicic lava flows which in turn could expand knowledge of pre-eruption compositional gradients and mixing processes in silicic magma bodies. However, thermal infrared image data may be greatly influenced by the range of vesicular textures which occur on silicic flows . To investigate the effect of vesicularity on TIMS imagery independent of chemical variations, we studied Little Glass Mountain at the Medicine Lake Volcano of northern California, a large rhyolitic flow of uniform composition but textural heterogeneity. The imagery was recalibrated so that the digital number values for a lake in the scene matched a calculated ideal spectrum for water. TIMS spectra for the lava show useful differences in coarsely and finely vesicular pumice data, particularly in TIMS bands 3 and 4. Images generated by ratioing these bands accurately map out those areas known from field studies to be coarsely vesicular pumice. These texture-related emissivity variations are probably due to the larger vesicles being relatively deeper and separated by smaller septa leaving less smooth glass available to give the characteristic emission of the lava. In studies of inaccessible lava flows (as on Mars) areas of coarsely vesicular pumice must be identified and avoided before chemical variations can be interpreted. Remotely determined distributions of vesicular and glassy textures can also be related to the volatile contents and potential hazards associated with the emplacement of silicic lava flows on Earth. Title: Mapping the Distribution of Vesicular Textures on Silicic Lavas Using the Thermal Infrared Multispectral Scanner Author: Ondrusek, Jaime, Christensen, Philip R., Fink, Jonathan Year: 1993 The Thermal Infrared Multispectral Scanner (TlMS) is a potentially powerful tool for mapping detailed chemical variations in silicic lava flows which in turn could expand knowledge of pre-eruption compositional gradients and mixing processes in silicic magma bodies. However, thermal infrared image data may be greatly influenced by the range of vesicular textures which occur on silicic flows . To investigate the effect of vesicularity on TIMS imagery independent of chemical variations, we studied Little Glass Mountain at the Medicine Lake Volcano of northern California, a large rhyolitic flow of uniform composition but textural heterogeneity. The imagery was recalibrated so that the digital number values for a lake in the scene matched a calculated ideal spectrum for water. TIMS spectra for the lava show useful differences in coarsely and finely vesicular pumice data, particularly in TIMS bands 3 and 4. Images generated by ratioing these bands accurately map out those areas known from field studies to be coarsely vesicular pumice. These texture-related emissivity variations are probably due to the larger vesicles being relatively deeper and separated by smaller septa leaving less smooth glass available to give the characteristic emission of the lava. In studies of inaccessible lava flows (as on Mars) areas of coarsely vesicular pumice must be identified and avoided before chemical variations can be interpreted. Remotely determined distributions of vesicular and glassy textures can also be related to the volatile contents and potential hazards associated with the emplacement of silicic lava flows on Earth. Close

• 63. [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

• 64. [Article] Assessing Hydrologic and Water Quality Sensitivities to Precipitation Changes, Urban Growth and Land Management Using SWAT

  Precipitation changes and urban growth are two factors altering the state of water quality. Changes in precipitation will alter the amount and timing of flows, and the corresponding sediment and nutrient ...

  Citation × Citation Citation Abstract Copy Title: Assessing Hydrologic and Water Quality Sensitivities to Precipitation Changes, Urban Growth and Land Management Using SWAT Author: Psaris, Alexander Michael Year: 2014 Precipitation changes and urban growth are two factors altering the state of water quality. Changes in precipitation will alter the amount and timing of flows, and the corresponding sediment and nutrient dynamics. Meanwhile, densification associated with urban growth will create more impervious surfaces which will alter sediment and nutrient loadings. Land and water managers often rely on models to develop possible future scenarios and devise management responses to these projected changes. We use the Soil and Water Assessment Tool (SWAT) to assess the sensitivities of stream flow, sediment, and nutrient loads in two urbanizing watersheds in Northwest Oregon, USA to various climate and urbanization scenarios. We evaluate the spatial patterns climate change and urban growth will have on water, sediment and nutrient yields. We also identify critical source areas (CSAs) and investigate how implementation of vegetative filter strips (VFS) could ameliorate the effects of these changes. Our findings suggest that: 1) Water yield is tightly coupled to precipitation. 2) Large increases in winter and spring precipitation provide enough sub-surface storage to increase summertime water yields despite a moderate decrease in summer precipitation. 3) Expansion of urban areas increases surface runoff and has mixed effects on sediment and nutrients. 4) Implementation of VFS reduces pollutant loads helping overall watershed health. This research demonstrates the usefulness of SWAT in facilitating informed land and water management decisions. Title: Assessing Hydrologic and Water Quality Sensitivities to Precipitation Changes, Urban Growth and Land Management Using SWAT Author: Psaris, Alexander Michael Year: 2014 Precipitation changes and urban growth are two factors altering the state of water quality. Changes in precipitation will alter the amount and timing of flows, and the corresponding sediment and nutrient dynamics. Meanwhile, densification associated with urban growth will create more impervious surfaces which will alter sediment and nutrient loadings. Land and water managers often rely on models to develop possible future scenarios and devise management responses to these projected changes. We use the Soil and Water Assessment Tool (SWAT) to assess the sensitivities of stream flow, sediment, and nutrient loads in two urbanizing watersheds in Northwest Oregon, USA to various climate and urbanization scenarios. We evaluate the spatial patterns climate change and urban growth will have on water, sediment and nutrient yields. We also identify critical source areas (CSAs) and investigate how implementation of vegetative filter strips (VFS) could ameliorate the effects of these changes. Our findings suggest that: 1) Water yield is tightly coupled to precipitation. 2) Large increases in winter and spring precipitation provide enough sub-surface storage to increase summertime water yields despite a moderate decrease in summer precipitation. 3) Expansion of urban areas increases surface runoff and has mixed effects on sediment and nutrients. 4) Implementation of VFS reduces pollutant loads helping overall watershed health. This research demonstrates the usefulness of SWAT in facilitating informed land and water management decisions. Close

• 65. [Article] The effect of human activity on the middle course of the Tualatin River, Oregon

  A diurnal study of biological, chemical, and physical parameters was made on the middle course of the, Tualatin River, which drains a 1840 km2 (711 mi2) basin adjacent to metropolitan Portland, Oregon. ...

  Citation × Citation Citation Abstract Copy Title: The effect of human activity on the middle course of the Tualatin River, Oregon Author: Carter, Lolita M. Year: 1975 A diurnal study of biological, chemical, and physical parameters was made on the middle course of the, Tualatin River, which drains a 1840 km2 (711 mi2) basin adjacent to metropolitan Portland, Oregon. This portion of the river lies along land in transition of use from rural agriculture to highly urbanized development. There is no nutrient loading of the river from farming practices because there was no return of water from summer, sprinkler irrigation of commercial crops. However, irrigation significantly reduces the volume of water in the river in the summers. Effluents from sewage treatment plants flowing into the tributaries that drain the highly urbanized eastern areas of the river basin are the main cause of degraded water quality and algal biomass in the lower reaches of the river. The Tualatin River above the mouth of Rock Creek is relatively unpolluted, but downstream from Rock Creek the river is highly eutrophic and during the periods of low flow in the summer serves as a sewage oxidation channel. In this same portion of the river there is also evidence that nitrification occurs. Winter floods leach nitrate-nitrogen from the basin, but in the summer the possibility exists. that nitrate-nitrogen may be a limiting nutrient for algal productivity in the river above Hillsboro. The principal source of poly-phosphates is from sewage treatment plant effluents, but concentrations of poly-phosphates in the middle reaches of the river indicate that there is a natural source of poly- and/or ortho-phosphates in the watershed. Removal of phosphorous compounds from the effluents probably would not affect the large algal blooms occurring in the river below Hillsboro. Trace metal analyses indicated that iron, potassium, nickel, zinc, lead, copper, cobalt, and chromium concentrations were higher during flooding. Turbidity readings suggest that these trace elements are deposited on the floodplain. Melted snow water, which caused one of the winter floods, contained concentrations of zinc, ·copper, and lead greater than those found in the river during the flood. Greater concentrations of arsenic and zinc came from farmland than from urban areas. Diversities of the net plankton as measured by the Shannon-Weaver Index did not change from season to season, nor with downstream flow. Species in the net plankton were benthic forms at the upper stations and planktonic forms downstream from Hillsboro, especially in the summer when the reduced flow caused the river to pond. The enriched effluents from Rock Creek did not affect the diversity of the organisms downstream, but supported a larger biomass. By rating the diversities with other studies it was found that the middle course of the Tualatin River is eutrophic but not heavily polluted. A diurnal study was especially valuable from April to September, inclusive, when insolation and temperatures favored biological activities such as photosynthesis and decomposition. From November to January little diurnal change in the water quality was found. Farming had its greatest impact in the quantity of water and municipalities had a more serious impact on the water quality in the middle course of the Tualatin River. Even with the reduced flow from agricultural irrigation, the river can maintain relatively good water quality, except when effluents from sewage plants caused highly eutrophic conditions. Title: The effect of human activity on the middle course of the Tualatin River, Oregon Author: Carter, Lolita M. Year: 1975 A diurnal study of biological, chemical, and physical parameters was made on the middle course of the, Tualatin River, which drains a 1840 km2 (711 mi2) basin adjacent to metropolitan Portland, Oregon. This portion of the river lies along land in transition of use from rural agriculture to highly urbanized development. There is no nutrient loading of the river from farming practices because there was no return of water from summer, sprinkler irrigation of commercial crops. However, irrigation significantly reduces the volume of water in the river in the summers. Effluents from sewage treatment plants flowing into the tributaries that drain the highly urbanized eastern areas of the river basin are the main cause of degraded water quality and algal biomass in the lower reaches of the river. The Tualatin River above the mouth of Rock Creek is relatively unpolluted, but downstream from Rock Creek the river is highly eutrophic and during the periods of low flow in the summer serves as a sewage oxidation channel. In this same portion of the river there is also evidence that nitrification occurs. Winter floods leach nitrate-nitrogen from the basin, but in the summer the possibility exists. that nitrate-nitrogen may be a limiting nutrient for algal productivity in the river above Hillsboro. The principal source of poly-phosphates is from sewage treatment plant effluents, but concentrations of poly-phosphates in the middle reaches of the river indicate that there is a natural source of poly- and/or ortho-phosphates in the watershed. Removal of phosphorous compounds from the effluents probably would not affect the large algal blooms occurring in the river below Hillsboro. Trace metal analyses indicated that iron, potassium, nickel, zinc, lead, copper, cobalt, and chromium concentrations were higher during flooding. Turbidity readings suggest that these trace elements are deposited on the floodplain. Melted snow water, which caused one of the winter floods, contained concentrations of zinc, ·copper, and lead greater than those found in the river during the flood. Greater concentrations of arsenic and zinc came from farmland than from urban areas. Diversities of the net plankton as measured by the Shannon-Weaver Index did not change from season to season, nor with downstream flow. Species in the net plankton were benthic forms at the upper stations and planktonic forms downstream from Hillsboro, especially in the summer when the reduced flow caused the river to pond. The enriched effluents from Rock Creek did not affect the diversity of the organisms downstream, but supported a larger biomass. By rating the diversities with other studies it was found that the middle course of the Tualatin River is eutrophic but not heavily polluted. A diurnal study was especially valuable from April to September, inclusive, when insolation and temperatures favored biological activities such as photosynthesis and decomposition. From November to January little diurnal change in the water quality was found. Farming had its greatest impact in the quantity of water and municipalities had a more serious impact on the water quality in the middle course of the Tualatin River. Even with the reduced flow from agricultural irrigation, the river can maintain relatively good water quality, except when effluents from sewage plants caused highly eutrophic conditions. Close

• 66. [Article] Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska

  Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ~20 to 30 x ~10⁶ m³ and then drains subglacially within 2 to 3 days. During the ...

  Citation × Citation Citation Abstract Copy Title: Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska Author: Anderson, Suzanne P., Walder, Joseph S., Anderson, Robert S., Kraal, Erin R., Cunico, Michelle, Fountain, Andrew G., Trabant, Dennis C. Year: 2003 Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ~20 to 30 x ~10⁶ m³ and then drains subglacially within 2 to 3 days. During the 1999 and 2000 jökulhlaups, we carried out a series of planned observations around the lake and in the Kennicott River, which drains the glacier. Approximately 20% of the lake volume was contained within a subglacial water ‘‘wedge’’ beneath the ice dam. The entire volume of the lake drains through the wedge; hydraulic head loss through this constriction may be responsible for the fairly symmetrical shape of the HCL outflow hydrographs, deduced from lake level records, basin hypsometry, and collapse of the ice dam. The flood hydrographs in the Kennicott River are similar in shape to the outflow hydrographs, and within error, lake volume matched the river flood volume in both years. Up to 12 x 10⁶ m³ of water was temporarily stored within the glacier during the 2000 jökulhlaup. During the 2000 jökulhlaup the background flow in the Kennicott River shifted to a dilute chemical composition. As the HCL jökulhlaup progressed, Donoho Falls Lake filled with water whose chemistry was closer to that of the background flow in Kennicott River than to HCL water. Comparison of these chemical signals with typical summer variations in Kennicott River chemistry suggests that the jökulhlaup created high subglacial water pressure that impeded normal drainage of solute-rich water from a distributed drainage system into a conduit system at the glacier bed and even caused flow direction locally to reverse. Title: Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska Author: Anderson, Suzanne P., Walder, Joseph S., Anderson, Robert S., Kraal, Erin R., Cunico, Michelle, Fountain, Andrew G., Trabant, Dennis C. Year: 2003 Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ~20 to 30 x ~10⁶ m³ and then drains subglacially within 2 to 3 days. During the 1999 and 2000 jökulhlaups, we carried out a series of planned observations around the lake and in the Kennicott River, which drains the glacier. Approximately 20% of the lake volume was contained within a subglacial water ‘‘wedge’’ beneath the ice dam. The entire volume of the lake drains through the wedge; hydraulic head loss through this constriction may be responsible for the fairly symmetrical shape of the HCL outflow hydrographs, deduced from lake level records, basin hypsometry, and collapse of the ice dam. The flood hydrographs in the Kennicott River are similar in shape to the outflow hydrographs, and within error, lake volume matched the river flood volume in both years. Up to 12 x 10⁶ m³ of water was temporarily stored within the glacier during the 2000 jökulhlaup. During the 2000 jökulhlaup the background flow in the Kennicott River shifted to a dilute chemical composition. As the HCL jökulhlaup progressed, Donoho Falls Lake filled with water whose chemistry was closer to that of the background flow in Kennicott River than to HCL water. Comparison of these chemical signals with typical summer variations in Kennicott River chemistry suggests that the jökulhlaup created high subglacial water pressure that impeded normal drainage of solute-rich water from a distributed drainage system into a conduit system at the glacier bed and even caused flow direction locally to reverse. Close

• 67. [Article] Groundwater-Surface Water Interactions near Mosier, Oregon

  The town of Mosier, Oregon, is located near the east, dry end of the Columbia River Gorge, and the local area is known for cherry orchards that rely heavily on groundwater for irrigation. The CRBG groundwater ...

  Citation × Citation Citation Abstract Copy Title: Groundwater-Surface Water Interactions near Mosier, Oregon Author: Jones, Cullen Brandon Year: 2016 The town of Mosier, Oregon, is located near the east, dry end of the Columbia River Gorge, and the local area is known for cherry orchards that rely heavily on groundwater for irrigation. The CRBG groundwater system in Mosier has experienced groundwater declines of up to 60 meters due to over-pumping and or commingling. Declining groundwater levels have led to concerns over the sustainability of the resource, as it is the principle water source for irrigation and domestic use. Despite numerous previous studies of groundwater flow in CRBG aquifers here and elsewhere in the Columbia River basin, an aspect that has received relatively little attention is the interaction between groundwater and surface waters at locations where interflow zones are intersected by the surface waters. The objective of my research is to investigate how CRBG interflow zone exposures in Mosier Creek may be controlling groundwater elevations in the area. The methods used include: (1) geochemical analysis of well cuttings and detailed geologic mapping along area streams to identify interflow zones of individual CRBG flows, (2) analysis of stream discharge data and groundwater elevation data to confirm exchange of groundwater and surface waters, and (3) collection and analyses of 31 water samples from area wells, streams, and springs, to determine if waters from individual CRBG aquifers can be hydrochemically identified and to further constrain understanding of surface and groundwater interactions. My study confirms that the general elevation of the Pomona Member and Basalt of Lolo interflow zone creek exposure is coincident with the elevation where a change in slope of the decline trend in 2004 is seen in Mosier area well hydrographs. Furthermore, the results of stream discharge data indicated a close connection between drawdown from groundwater pumping during irrigation season and groundwater- surface water interaction. At the time of drawdown in the upper-most CRBG aquifer (Pomona), the stream transitions from gaining to losing water into the groundwater system. Elemental chemistry data indicates the Frenchman Springs Sentinel Gap aquifer waters are the most evolved waters in this study. Stable isotopic data reinforced this determination as the Sentinel Gap waters are the lightest, or most negative, with regard to δD and δ18O. Sentinel Gap samples were more depleted than other aquifer samples by 4.38 to 6.89 0/100 for δD and 0.39 to 0.59 0/100 for δ18O. The results of the general chemistry and isotope data reveal a more evolved chemical signature in lower watershed groundwater versus a less evolved signature for waters from wells located higher up on the Columbia Hills anticline. This was interpreted to be the result of the major structural features in the area providing for a more regional pathway of recharge in lower watershed groundwaters, versus a more local source of recharge for upper watershed groundwaters. There was also a pronounced commingled signature in the elemental ratios of lower watershed aquifer waters. The suspected mechanism of recharge to lower watershed wells is through younger Cascadian deposits upslope from the local watershed. The findings of this study reveal the importance of a detailed understanding of CRBG stratigraphy and its relation to surface waters, especially for other areas within the Yakima Fold Belt or Oregon and Washington. Studies that do not consider the influence that individual CRBG flows can have on groundwater-surface water interactions, and the groundwater system as a whole, run the risk of improperly assessing the groundwater resource for a region. Title: Groundwater-Surface Water Interactions near Mosier, Oregon Author: Jones, Cullen Brandon Year: 2016 The town of Mosier, Oregon, is located near the east, dry end of the Columbia River Gorge, and the local area is known for cherry orchards that rely heavily on groundwater for irrigation. The CRBG groundwater system in Mosier has experienced groundwater declines of up to 60 meters due to over-pumping and or commingling. Declining groundwater levels have led to concerns over the sustainability of the resource, as it is the principle water source for irrigation and domestic use. Despite numerous previous studies of groundwater flow in CRBG aquifers here and elsewhere in the Columbia River basin, an aspect that has received relatively little attention is the interaction between groundwater and surface waters at locations where interflow zones are intersected by the surface waters. The objective of my research is to investigate how CRBG interflow zone exposures in Mosier Creek may be controlling groundwater elevations in the area. The methods used include: (1) geochemical analysis of well cuttings and detailed geologic mapping along area streams to identify interflow zones of individual CRBG flows, (2) analysis of stream discharge data and groundwater elevation data to confirm exchange of groundwater and surface waters, and (3) collection and analyses of 31 water samples from area wells, streams, and springs, to determine if waters from individual CRBG aquifers can be hydrochemically identified and to further constrain understanding of surface and groundwater interactions. My study confirms that the general elevation of the Pomona Member and Basalt of Lolo interflow zone creek exposure is coincident with the elevation where a change in slope of the decline trend in 2004 is seen in Mosier area well hydrographs. Furthermore, the results of stream discharge data indicated a close connection between drawdown from groundwater pumping during irrigation season and groundwater- surface water interaction. At the time of drawdown in the upper-most CRBG aquifer (Pomona), the stream transitions from gaining to losing water into the groundwater system. Elemental chemistry data indicates the Frenchman Springs Sentinel Gap aquifer waters are the most evolved waters in this study. Stable isotopic data reinforced this determination as the Sentinel Gap waters are the lightest, or most negative, with regard to δD and δ18O. Sentinel Gap samples were more depleted than other aquifer samples by 4.38 to 6.89 0/100 for δD and 0.39 to 0.59 0/100 for δ18O. The results of the general chemistry and isotope data reveal a more evolved chemical signature in lower watershed groundwater versus a less evolved signature for waters from wells located higher up on the Columbia Hills anticline. This was interpreted to be the result of the major structural features in the area providing for a more regional pathway of recharge in lower watershed groundwaters, versus a more local source of recharge for upper watershed groundwaters. There was also a pronounced commingled signature in the elemental ratios of lower watershed aquifer waters. The suspected mechanism of recharge to lower watershed wells is through younger Cascadian deposits upslope from the local watershed. The findings of this study reveal the importance of a detailed understanding of CRBG stratigraphy and its relation to surface waters, especially for other areas within the Yakima Fold Belt or Oregon and Washington. Studies that do not consider the influence that individual CRBG flows can have on groundwater-surface water interactions, and the groundwater system as a whole, run the risk of improperly assessing the groundwater resource for a region. Close

• 68. [Article] Validation of the CE-QUAL-W2 Version 3 River Basin Hydrodynamic and Water Quality Model

  CE-QUAL-W2 Version 3, a 2-D (longitudinal-vertical) hydrodynamic and water quality model for river basins combining both river and stratified river-estuary and lakereservoir flow, is a development product ...

  Citation × Citation Citation Abstract Copy Title: Validation of the CE-QUAL-W2 Version 3 River Basin Hydrodynamic and Water Quality Model Author: Wells, Scott A. Year: 2002 CE-QUAL-W2 Version 3, a 2-D (longitudinal-vertical) hydrodynamic and water quality model for river basins combining both river and stratified river-estuary and lakereservoir flow, is a development product of the Waterways Experiment Station in Vicksburg, MS, USA. With the development and release of any revised or reformulated model codes, significant model validation is required. This includes comparison of model results to simple analytical solutions for hydrodynamics and water quality transport, as well as comparison to laboratory and field data. In this paper, the model is compared to numerous analytical solutions for mass transport (1-D advective mass transport) and hydrodynamics (impulsive wind stress on water surface, seiching). Suggestions are presented for proper validation protocols for hydrodynamic and water quality models. Title: Validation of the CE-QUAL-W2 Version 3 River Basin Hydrodynamic and Water Quality Model Author: Wells, Scott A. Year: 2002 CE-QUAL-W2 Version 3, a 2-D (longitudinal-vertical) hydrodynamic and water quality model for river basins combining both river and stratified river-estuary and lakereservoir flow, is a development product of the Waterways Experiment Station in Vicksburg, MS, USA. With the development and release of any revised or reformulated model codes, significant model validation is required. This includes comparison of model results to simple analytical solutions for hydrodynamics and water quality transport, as well as comparison to laboratory and field data. In this paper, the model is compared to numerous analytical solutions for mass transport (1-D advective mass transport) and hydrodynamics (impulsive wind stress on water surface, seiching). Suggestions are presented for proper validation protocols for hydrodynamic and water quality models. Close

• 69. [Article] Basis of the CE-QUAL-W2 Version 3 River Basin Hydrodynamic and Water Quality Model

  CE-QUAL-W2 Version 3, a 2-D (longitudinal-vertical) hydrodynamic and water quality model for river basins combining both river and stratified river-estuary and lake-reservoir flow, is a development product ...

  Citation × Citation Citation Abstract Copy Title: Basis of the CE-QUAL-W2 Version 3 River Basin Hydrodynamic and Water Quality Model Author: Wells, Scott A. Year: 2002 CE-QUAL-W2 Version 3, a 2-D (longitudinal-vertical) hydrodynamic and water quality model for river basins combining both river and stratified river-estuary and lake-reservoir flow, is a development product of the Waterways Experiment Station in Vicksburg, MS, USA. With the development and release of any revised or reformulated model codes, significant model validation is required. This includes comparison of model results to simple analytical solutions for hydrodynamics and water quality transport, as well as comparison to laboratory and field data. In this paper, the model is compared to numerous analytical solutions for mass transport (1- D advective mass transport) and hydrodynamics (impulsive wind stress on water surface, seiching). Suggestions are presented for proper validation protocols for hydrodynamic and water quality models. Title: Basis of the CE-QUAL-W2 Version 3 River Basin Hydrodynamic and Water Quality Model Author: Wells, Scott A. Year: 2002 CE-QUAL-W2 Version 3, a 2-D (longitudinal-vertical) hydrodynamic and water quality model for river basins combining both river and stratified river-estuary and lake-reservoir flow, is a development product of the Waterways Experiment Station in Vicksburg, MS, USA. With the development and release of any revised or reformulated model codes, significant model validation is required. This includes comparison of model results to simple analytical solutions for hydrodynamics and water quality transport, as well as comparison to laboratory and field data. In this paper, the model is compared to numerous analytical solutions for mass transport (1- D advective mass transport) and hydrodynamics (impulsive wind stress on water surface, seiching). Suggestions are presented for proper validation protocols for hydrodynamic and water quality models. Close

• 70. [Article] Impacts of Columbia River Discharge on Salmonid Habitat: 2. Changes in Shallow-Water Habitat

  This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, ...

  Citation × Citation Citation Abstract Copy Title: Impacts of Columbia River Discharge on Salmonid Habitat: 2. Changes in Shallow-Water Habitat Author: Jay, David A., Kukulka, Tobias Year: 2003 This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, subtidal river stage model that explains ~90% of the stage variance in the tidal river. This model and the tidal model developed in part 1 (Kukulka and Jay, 2003) uncouple the nonlinear interaction of river tides and river stage by referring both to external forcing by river discharge, ocean tides, and atmospheric pressure. Applying the two models, daily high-water levels were predicted for a reach from rkm-50 to rkm-90 during 1974 to 1998, the period of contemporary management. Predicted water levels were related to the bathymetry and topography to determine the changes in shallow-water habitat area (SWHA) caused by flood control dikes and altered flow management. Model results suggest that diking and a >40% reduction of peak flows have reduced SWHA by ~62% during the crucial spring freshet period during which juvenile salmon use of SWHA is maximal. Taken individually, diking and flow cycle alteration reduced spring freshet SWHA by 52% and 29%, respectively. SWHA has been both displaced to lower elevations and modified in its character because tidal range has increased. Our models of these processes are economical for the very long simulations (seasons to centuries) needed to understand historic changes and climate impacts on SWH. Through analysis of the nonlinear processes controlling surface elevation in a tidal river, we have identified some of the mechanisms that link freshwater discharge to SWH and salmonid survival. Title: Impacts of Columbia River Discharge on Salmonid Habitat: 2. Changes in Shallow-Water Habitat Author: Jay, David A., Kukulka, Tobias Year: 2003 This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, subtidal river stage model that explains ~90% of the stage variance in the tidal river. This model and the tidal model developed in part 1 (Kukulka and Jay, 2003) uncouple the nonlinear interaction of river tides and river stage by referring both to external forcing by river discharge, ocean tides, and atmospheric pressure. Applying the two models, daily high-water levels were predicted for a reach from rkm-50 to rkm-90 during 1974 to 1998, the period of contemporary management. Predicted water levels were related to the bathymetry and topography to determine the changes in shallow-water habitat area (SWHA) caused by flood control dikes and altered flow management. Model results suggest that diking and a >40% reduction of peak flows have reduced SWHA by ~62% during the crucial spring freshet period during which juvenile salmon use of SWHA is maximal. Taken individually, diking and flow cycle alteration reduced spring freshet SWHA by 52% and 29%, respectively. SWHA has been both displaced to lower elevations and modified in its character because tidal range has increased. Our models of these processes are economical for the very long simulations (seasons to centuries) needed to understand historic changes and climate impacts on SWH. Through analysis of the nonlinear processes controlling surface elevation in a tidal river, we have identified some of the mechanisms that link freshwater discharge to SWH and salmonid survival. Close