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• 11. [Article] Flood control in the Pacific South Coastal Basin

  Citation × Citation Citation Abstract Copy Title: Flood control in the Pacific South Coastal Basin Author: Miller, James E. Title: Flood control in the Pacific South Coastal Basin Author: Miller, James E. Close

• 12. [Article] A general theory of flooding implementing the cuspoid catastrophe

  The flooding phenomenon can be defined as the maximum attainable flow condition beyond which the well defined countercurrent flow pattern can no longer exist. Thus the countercurrent flow limit (CCFL) ...

  Citation × Citation Citation Abstract Copy Title: A general theory of flooding implementing the cuspoid catastrophe Author: Lafi, Abd Y. The flooding phenomenon can be defined as the maximum attainable flow condition beyond which the well defined countercurrent flow pattern can no longer exist. Thus the countercurrent flow limit (CCFL) or the flooding limit may be thought of as the flow condition at which the strong interaction between the two phases occurs. Considerable effort has been devoted to understanding and analyzing the flooding transition in many fields. For example; the flooding phenomenon is one of the important phenomena encountered in the safety analysis of light water reactors (pressurized water reactors and boiling water reactors). Accurate predictions of flooding behavior are particularly important in the assessment of emergency core cooling system (ECCS) performance. Currently, the postulated loss-of-coolant accident (LOCA) is considered the design basis accident. A physical understanding of the flooding phenomenon will help assess core refill during the course of a LOCA. Understanding the physical mechanisms of the flooding phenomenon might help establish more reliable equations and correlations which accurately describe the thermal hydraulic behavior of the system. The models can provide best-estimate capability to the design codes used in the evaluation of ECCS performance. The primary concern of this study was to: 1. Understand the physical mechanisms involved in the flooding phenomenon in order to derive a suitable analytical model. 2. Show that the combination of: a. Linear Instability Theory b. Kinematic Wave Theory c. Catastrophe Theory can provide a general model for flooding phenomenon. The theoretical model derived using the aforementioned combination of theories indicates good agreement between the experimental and the predicted values. Comparisons have been made using a large volume of air-water flooding data. Title: A general theory of flooding implementing the cuspoid catastrophe Author: Lafi, Abd Y. The flooding phenomenon can be defined as the maximum attainable flow condition beyond which the well defined countercurrent flow pattern can no longer exist. Thus the countercurrent flow limit (CCFL) or the flooding limit may be thought of as the flow condition at which the strong interaction between the two phases occurs. Considerable effort has been devoted to understanding and analyzing the flooding transition in many fields. For example; the flooding phenomenon is one of the important phenomena encountered in the safety analysis of light water reactors (pressurized water reactors and boiling water reactors). Accurate predictions of flooding behavior are particularly important in the assessment of emergency core cooling system (ECCS) performance. Currently, the postulated loss-of-coolant accident (LOCA) is considered the design basis accident. A physical understanding of the flooding phenomenon will help assess core refill during the course of a LOCA. Understanding the physical mechanisms of the flooding phenomenon might help establish more reliable equations and correlations which accurately describe the thermal hydraulic behavior of the system. The models can provide best-estimate capability to the design codes used in the evaluation of ECCS performance. The primary concern of this study was to: 1. Understand the physical mechanisms involved in the flooding phenomenon in order to derive a suitable analytical model. 2. Show that the combination of: a. Linear Instability Theory b. Kinematic Wave Theory c. Catastrophe Theory can provide a general model for flooding phenomenon. The theoretical model derived using the aforementioned combination of theories indicates good agreement between the experimental and the predicted values. Comparisons have been made using a large volume of air-water flooding data. Close

• 13. [Article] Ecological responses to riverine floods and flow alteration

  Floods are major disturbance events for riverine ecosystems, directly and indirectly impacting organisms and their habitat. In this study I investigated the role of riverine floods and flow alteration ...

  Citation × Citation Citation Abstract Copy Title: Ecological responses to riverine floods and flow alteration Author: McMullen, Laura E. Floods are major disturbance events for riverine ecosystems, directly and indirectly impacting organisms and their habitat. In this study I investigated the role of riverine floods and flow alteration in regulating aquatic macroinvertebrate population and community structure. I examined this problem using a variety of methods: a meta-analytic review of primary studies from the literature, a mathematical model synthesizing population and flood ecology, a multi-year experimental flood program in an arid-land river, and a field investigation of flood recovery behaviors in a charismatic larval odonate. I found that floods significantly reduced invertebrate abundance in the short term, but had varied effects across particular study sites, microhabitats, and taxonomic groups. I determined that both resistant and resilient capabilities are important to persistence of invertebrate populations after disturbance events, and that these traits may act in a binary fashion. Recovery over time of invertebrate populations may be partially due to "hidden resistance" of spatially displaced individuals in side-channels, benthic substrate, and vegetation or wood. Some invertebrates adapted to flood-prone rivers may possess behavioral adaptations for returning to the main-channel of the river after flood events. This dissertation contributes to riverine disturbance ecology and provides information useful to prediction and management of ecosystem flows in rivers. Title: Ecological responses to riverine floods and flow alteration Author: McMullen, Laura E. Floods are major disturbance events for riverine ecosystems, directly and indirectly impacting organisms and their habitat. In this study I investigated the role of riverine floods and flow alteration in regulating aquatic macroinvertebrate population and community structure. I examined this problem using a variety of methods: a meta-analytic review of primary studies from the literature, a mathematical model synthesizing population and flood ecology, a multi-year experimental flood program in an arid-land river, and a field investigation of flood recovery behaviors in a charismatic larval odonate. I found that floods significantly reduced invertebrate abundance in the short term, but had varied effects across particular study sites, microhabitats, and taxonomic groups. I determined that both resistant and resilient capabilities are important to persistence of invertebrate populations after disturbance events, and that these traits may act in a binary fashion. Recovery over time of invertebrate populations may be partially due to "hidden resistance" of spatially displaced individuals in side-channels, benthic substrate, and vegetation or wood. Some invertebrates adapted to flood-prone rivers may possess behavioral adaptations for returning to the main-channel of the river after flood events. This dissertation contributes to riverine disturbance ecology and provides information useful to prediction and management of ecosystem flows in rivers. Close

• 14. [Article] An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability

  Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel ...

  Citation × Citation Citation Abstract Copy Title: An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability Author: Morét, Stephanie L. Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel and if the channel stability survey that was being used accurately predicted the channels resistance to change resulting from a flood. The channel stability survey that was used was the method described in the 'Channel Stability Evaluation and Stream Reach Inventory' designed by the USDA Forest Service, Northern Region, in Colorado (Pfankuch, 1978). This was a non-parametric study, based on an opportunity to reoccupy survey locations from a previous study. A model was proposed to describe the 1995 ratings as predictions for change should a flood event occur. This predicted change was compared to the actual change that occurred as a result of the 1996 flood in order to test the surveys ability to accurately predict change. Changes in the survey totals, the 15 channel stability indicator items that compose the survey, and the sediment distribution were evaluated within and between years at the reach, station and stream scale. An increase in the percentage of fine gravel occurred at all scales when post-flood and pre-flood sediment distribution was compared. Except for an increase in fine gravel, the stream remained similar to its pre-flood state. In 1995, the stream's channel stability was rated as 'fair', indicating that a moderate amount of change should take place if a flood occurred. The 1995 predictions for change did not match the actual change observed after the February 1996 flood at the three scales when defined by the survey totals. When independently evaluating the fifteen individual channel stability indicator items, a considerable amount of change was detected at the reach level. Although change occurred in the indicator items at each reach, the stream average for each of the independent indicator items was similar between the two years. This may indicate that, although change occurred at the reach level, the stream maintained its physical diversity after the flood. The survey method was unable to accurately predict changes to Oak Creek incurred by the February 1996 flood when viewed at the entire stream level, yet it may be more applicable at the reach level when viewing specific changes to channel stability indicator items. In general, the Stream Reach Inventory and Channel Stability Evaluation is designed for observational efficiency but does not have sufficient scientific basis or measurement precision to accurately predict the extent or type of channel change. Title: An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability Author: Morét, Stephanie L. Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel and if the channel stability survey that was being used accurately predicted the channels resistance to change resulting from a flood. The channel stability survey that was used was the method described in the 'Channel Stability Evaluation and Stream Reach Inventory' designed by the USDA Forest Service, Northern Region, in Colorado (Pfankuch, 1978). This was a non-parametric study, based on an opportunity to reoccupy survey locations from a previous study. A model was proposed to describe the 1995 ratings as predictions for change should a flood event occur. This predicted change was compared to the actual change that occurred as a result of the 1996 flood in order to test the surveys ability to accurately predict change. Changes in the survey totals, the 15 channel stability indicator items that compose the survey, and the sediment distribution were evaluated within and between years at the reach, station and stream scale. An increase in the percentage of fine gravel occurred at all scales when post-flood and pre-flood sediment distribution was compared. Except for an increase in fine gravel, the stream remained similar to its pre-flood state. In 1995, the stream's channel stability was rated as 'fair', indicating that a moderate amount of change should take place if a flood occurred. The 1995 predictions for change did not match the actual change observed after the February 1996 flood at the three scales when defined by the survey totals. When independently evaluating the fifteen individual channel stability indicator items, a considerable amount of change was detected at the reach level. Although change occurred in the indicator items at each reach, the stream average for each of the independent indicator items was similar between the two years. This may indicate that, although change occurred at the reach level, the stream maintained its physical diversity after the flood. The survey method was unable to accurately predict changes to Oak Creek incurred by the February 1996 flood when viewed at the entire stream level, yet it may be more applicable at the reach level when viewing specific changes to channel stability indicator items. In general, the Stream Reach Inventory and Channel Stability Evaluation is designed for observational efficiency but does not have sufficient scientific basis or measurement precision to accurately predict the extent or type of channel change. Close

• 15. [Article] Quantifying invertebrate resistance to floods: a global-scale meta-analysis

  This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/.

  Citation × Citation Citation Abstract Copy Title: Quantifying invertebrate resistance to floods: a global-scale meta-analysis Author: Lytle, David A., McMullen, Laura E. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/. Title: Quantifying invertebrate resistance to floods: a global-scale meta-analysis Author: Lytle, David A., McMullen, Laura E. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/. Close

• 16. [Article] Prediction of peak flows for culvert design on small watersheds in Oregon

  Forest engineers must frequently make flood frequency estimates for very small watersheds when designing culvert installations. Empirical formulae and simplified rainfall runoff models, the most commonly ...

  Citation × Citation Citation Abstract Copy Title: Prediction of peak flows for culvert design on small watersheds in Oregon Author: Campbell, Alan J. Forest engineers must frequently make flood frequency estimates for very small watersheds when designing culvert installations. Empirical formulae and simplified rainfall runoff models, the most commonly used techniques to predict floods from very small watersheds, require considerable engineering judgement to give reasonable results. As an alternative to such methods, this study presents equations to predict peak flows on small watersheds in Oregon. The equations were developed from 80 watersheds ranging in size from 0.21 to 10.60 square miles. Oregon was divided into six physiographic regions based on previous flood frequency studies. In each region, annual peak flow data from gaging stations with more than 20 years of record were analyzed using four flood frequency distributions (Gumbel, two-parameter log-normal, three-parameter log-normal, log Pearson type III). The log Pearson type III distribution was found to be suitable for use in all regions of the state, based on the chi-square goodness of fit test. Flood magnitudes having recurrence intervals of 10, 25, 50, and 100 years were related to physical and climatic indices of drainage basins by multiple regression analysis. Drainage basin area (A) was the most important variable in explaining the variation of flood peaks in all regions. Mean basin elevation (E) and mean annual precipitation (P) were also significantly related to flood peaks in two regions in western Oregon. The following equations to predict the 25-year flood were developed for each physiographic region in Oregon: (1) Willamette region Q₂₅ = 156A·⁸⁰ (2) Coast region Q₂₅ = 6.31A¹⁰¹E·⁵¹ (3) Cascade region Q₂₅ = .O32A⁴⁴P¹·⁹⁷ (4) Rogue-Umpqua region Q₂₅ = l63A·⁷⁷ (5) Blue-Wallowa region Q₂₅ = 67.6A·⁴⁷ Title: Prediction of peak flows for culvert design on small watersheds in Oregon Author: Campbell, Alan J. Forest engineers must frequently make flood frequency estimates for very small watersheds when designing culvert installations. Empirical formulae and simplified rainfall runoff models, the most commonly used techniques to predict floods from very small watersheds, require considerable engineering judgement to give reasonable results. As an alternative to such methods, this study presents equations to predict peak flows on small watersheds in Oregon. The equations were developed from 80 watersheds ranging in size from 0.21 to 10.60 square miles. Oregon was divided into six physiographic regions based on previous flood frequency studies. In each region, annual peak flow data from gaging stations with more than 20 years of record were analyzed using four flood frequency distributions (Gumbel, two-parameter log-normal, three-parameter log-normal, log Pearson type III). The log Pearson type III distribution was found to be suitable for use in all regions of the state, based on the chi-square goodness of fit test. Flood magnitudes having recurrence intervals of 10, 25, 50, and 100 years were related to physical and climatic indices of drainage basins by multiple regression analysis. Drainage basin area (A) was the most important variable in explaining the variation of flood peaks in all regions. Mean basin elevation (E) and mean annual precipitation (P) were also significantly related to flood peaks in two regions in western Oregon. The following equations to predict the 25-year flood were developed for each physiographic region in Oregon: (1) Willamette region Q₂₅ = 156A·⁸⁰ (2) Coast region Q₂₅ = 6.31A¹⁰¹E·⁵¹ (3) Cascade region Q₂₅ = .O32A⁴⁴P¹·⁹⁷ (4) Rogue-Umpqua region Q₂₅ = l63A·⁷⁷ (5) Blue-Wallowa region Q₂₅ = 67.6A·⁴⁷ Close

• 17. [Article] Impacts of Agriculture on the Inland Capture Fisheries in the Mekong Delta

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Impacts of Agriculture on the Inland Capture Fisheries in the Mekong Delta Author: Vu, Vi An, Ngwenya, Elkana Abstract only. Title: Impacts of Agriculture on the Inland Capture Fisheries in the Mekong Delta Author: Vu, Vi An, Ngwenya, Elkana Abstract only. Close

• 18. [Article] Estimating residential flood control benefits using implicit price equations

  Citation × Citation Citation Abstract Copy Title: Estimating residential flood control benefits using implicit price equations Author: Thompson, Mark Edward Title: Estimating residential flood control benefits using implicit price equations Author: Thompson, Mark Edward Close

• 19. [Article] Locating villages in the floods: the use of RADARSAT imagery in the flood hazard management in Bangladesh

  Citation × Citation Citation Abstract Copy Title: Locating villages in the floods: the use of RADARSAT imagery in the flood hazard management in Bangladesh Author: Petry, Heather N. Title: Locating villages in the floods: the use of RADARSAT imagery in the flood hazard management in Bangladesh Author: Petry, Heather N. Close

• 20. [Article] Flood Forecast Modeling of the Willamette Basin Using HEC-CWMS and HEC-ResSim

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Flood Forecast Modeling of the Willamette Basin Using HEC-CWMS and HEC-ResSim Author: Christensen, Daniel, Goodell, Chris, Bogavelli, Shali Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Flood Forecast Modeling of the Willamette Basin Using HEC-CWMS and HEC-ResSim Author: Christensen, Daniel, Goodell, Chris, Bogavelli, Shali Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close