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• 11. [Article] Quantifying Uncertainty in Urban Flooding Analysis Considering Hydro-Climatic Projection and Urban Development Effects

  How will the combined impacts of land use change, climate change, and hydrologic modeling influence changes in urban flood frequency and what is the main uncertainty source of the results? Will such changes ...

  Citation × Citation Citation Abstract Copy Title: Quantifying Uncertainty in Urban Flooding Analysis Considering Hydro-Climatic Projection and Urban Development Effects Author: Jung, Il-Won, Chang, Heejun, Moradkhani, Hamid Year: 2011 How will the combined impacts of land use change, climate change, and hydrologic modeling influence changes in urban flood frequency and what is the main uncertainty source of the results? Will such changes differ by catchment with different degrees of current and future urban development? We attempt to answer these questions in two catchments with different degrees of urbanization, the Fanno catchment with 84% urban land use and the Johnson catchment with 36% urban land use, both located in the Pacific Northwest of the US. Five uncertainty sources – general circulation model (GCM) structures, future greenhouse gas (GHG) emission scenarios, land use change scenarios, natural variability, and hydrologic model parameters – are considered to compare the relative source of uncertainty in flood frequency projections. Two land use change scenarios, conservation and development, representing possible future land use changes are used for analysis. Results show the highest increase in flood frequency under the combination of medium high GHG emission (A1B) and development scenarios, and the lowest increase under the combination of low GHG emission (B1) and conservation scenarios. Although the combined impact is more significant to flood frequency change than individual scenarios, it does not linearly Title: Quantifying Uncertainty in Urban Flooding Analysis Considering Hydro-Climatic Projection and Urban Development Effects Author: Jung, Il-Won, Chang, Heejun, Moradkhani, Hamid Year: 2011 How will the combined impacts of land use change, climate change, and hydrologic modeling influence changes in urban flood frequency and what is the main uncertainty source of the results? Will such changes differ by catchment with different degrees of current and future urban development? We attempt to answer these questions in two catchments with different degrees of urbanization, the Fanno catchment with 84% urban land use and the Johnson catchment with 36% urban land use, both located in the Pacific Northwest of the US. Five uncertainty sources – general circulation model (GCM) structures, future greenhouse gas (GHG) emission scenarios, land use change scenarios, natural variability, and hydrologic model parameters – are considered to compare the relative source of uncertainty in flood frequency projections. Two land use change scenarios, conservation and development, representing possible future land use changes are used for analysis. Results show the highest increase in flood frequency under the combination of medium high GHG emission (A1B) and development scenarios, and the lowest increase under the combination of low GHG emission (B1) and conservation scenarios. Although the combined impact is more significant to flood frequency change than individual scenarios, it does not linearly Close

• 12. [Article] Channel Shallowing as Mitigation of Coastal Flooding

  Here, we demonstrate that reductions in the depth of inlets or estuary channels can be used to reduce or prevent coastal flooding. A validated hydrodynamic model of Jamaica Bay, New York City (NYC), is ...

  Citation × Citation Citation Abstract Copy Title: Channel Shallowing as Mitigation of Coastal Flooding Author: Orton, Philip M., Talke, Stefan A., Jay, David A., Yin, Larry, Blumberg, Alan F., Georgas, Nickitas, Zhao, Haihong, Roberts, Hugh J., MacManus, Kytt Year: 2015 Here, we demonstrate that reductions in the depth of inlets or estuary channels can be used to reduce or prevent coastal flooding. A validated hydrodynamic model of Jamaica Bay, New York City (NYC), is used to test nature-based adaptation measures in ameliorating flooding for NYC’s two largest historical coastal flood events. In addition to control runs with modern bathymetry, three altered landscape scenarios are tested: (1) increasing the area of wetlands to their 1879 footprint and bathymetry, but leaving deep shipping channels unaltered; (2) shallowing all areas deeper than 2 m in the bay to be 2 m below Mean Low Water; (3) shallowing only the narrowest part of the inlet to the bay. These three scenarios are deliberately extreme and designed to evaluate the leverage each approach exerts on water levels. They result in peak water level reductions of 0.3%, 15%, and 6.8% for Hurricane Sandy, and 2.4%, 46% and 30% for the Category-3 hurricane of 1821, respectively (bay-wide averages). These results suggest that shallowing can provide greater flood protection than wetland restoration, and it is particularly effective at reducing "fast-pulse" storm surges that rise and fall quickly over several hours, like that of the 1821 storm. Nonetheless, the goal of flood mitigation must be weighed against economic, navigation, and ecological needs, and practical concerns such as the availability of sediment. Title: Channel Shallowing as Mitigation of Coastal Flooding Author: Orton, Philip M., Talke, Stefan A., Jay, David A., Yin, Larry, Blumberg, Alan F., Georgas, Nickitas, Zhao, Haihong, Roberts, Hugh J., MacManus, Kytt Year: 2015 Here, we demonstrate that reductions in the depth of inlets or estuary channels can be used to reduce or prevent coastal flooding. A validated hydrodynamic model of Jamaica Bay, New York City (NYC), is used to test nature-based adaptation measures in ameliorating flooding for NYC’s two largest historical coastal flood events. In addition to control runs with modern bathymetry, three altered landscape scenarios are tested: (1) increasing the area of wetlands to their 1879 footprint and bathymetry, but leaving deep shipping channels unaltered; (2) shallowing all areas deeper than 2 m in the bay to be 2 m below Mean Low Water; (3) shallowing only the narrowest part of the inlet to the bay. These three scenarios are deliberately extreme and designed to evaluate the leverage each approach exerts on water levels. They result in peak water level reductions of 0.3%, 15%, and 6.8% for Hurricane Sandy, and 2.4%, 46% and 30% for the Category-3 hurricane of 1821, respectively (bay-wide averages). These results suggest that shallowing can provide greater flood protection than wetland restoration, and it is particularly effective at reducing "fast-pulse" storm surges that rise and fall quickly over several hours, like that of the 1821 storm. Nonetheless, the goal of flood mitigation must be weighed against economic, navigation, and ecological needs, and practical concerns such as the availability of sediment. Close

• 13. [Article] It’s an Emergency: The Portland State University Library Flood

  Preservation Librarian Kris Kern discusses flooding at the Portland State University Library and lessons learned to prevent extended damage to the Library collections.

  Citation × Citation Citation Abstract Copy Title: It’s an Emergency: The Portland State University Library Flood Author: Kern, Kristen Year: 2008 Preservation Librarian Kris Kern discusses flooding at the Portland State University Library and lessons learned to prevent extended damage to the Library collections. Title: It’s an Emergency: The Portland State University Library Flood Author: Kern, Kristen Year: 2008 Preservation Librarian Kris Kern discusses flooding at the Portland State University Library and lessons learned to prevent extended damage to the Library collections. Close

• 14. [Article] First season effects of managed flooding on the invasive species Phalaris arundinacea L. and shoreline vegetation communities in an urban wetland

  Recent management efforts in the Smith and Bybee Lakes Wildlife Area (SBL), a 700-ha preserve in north Portland, Oregon, have included using a water control structure to suppress invasive reed canarygrass ...

  Citation × Citation Citation Abstract Copy Title: First season effects of managed flooding on the invasive species Phalaris arundinacea L. and shoreline vegetation communities in an urban wetland Author: Jenkins, Noah John Year: 2005 Recent management efforts in the Smith and Bybee Lakes Wildlife Area (SBL), a 700-ha preserve in north Portland, Oregon, have included using a water control structure to suppress invasive reed canarygrass (Phalaris arundinacea L.) by flooding during spring and early summer growth periods. For the first year of managed flooding, I sought to determine: (a) the extent and distribution of reed canarygrass at SBL; (b) the effectiveness of the change in water level at suppressing reed canarygrass; and ( c) the effects of the change in water level on other plant species. I established 30 vegetation transects throughout SBL before completion of the water control structure. These transects were randomly distributed, placed perpendicularly to the shorelines of the wetlands, and had a cumulative length of 3.1 km. I measured vegetation on the transects in autumn 2003 and autumn 2004 using the line intercept method at 10-cm intervals. I surveyed the transects to generate elevation profiles, accurate to 0.15 cm, to determine depth and duration of flooding, which I correlated with vegetative changes. I also monitored inundation depth, growth, and phenological response of individual stands of reed canarygrass during the 2004 growing season. Title: First season effects of managed flooding on the invasive species Phalaris arundinacea L. and shoreline vegetation communities in an urban wetland Author: Jenkins, Noah John Year: 2005 Recent management efforts in the Smith and Bybee Lakes Wildlife Area (SBL), a 700-ha preserve in north Portland, Oregon, have included using a water control structure to suppress invasive reed canarygrass (Phalaris arundinacea L.) by flooding during spring and early summer growth periods. For the first year of managed flooding, I sought to determine: (a) the extent and distribution of reed canarygrass at SBL; (b) the effectiveness of the change in water level at suppressing reed canarygrass; and ( c) the effects of the change in water level on other plant species. I established 30 vegetation transects throughout SBL before completion of the water control structure. These transects were randomly distributed, placed perpendicularly to the shorelines of the wetlands, and had a cumulative length of 3.1 km. I measured vegetation on the transects in autumn 2003 and autumn 2004 using the line intercept method at 10-cm intervals. I surveyed the transects to generate elevation profiles, accurate to 0.15 cm, to determine depth and duration of flooding, which I correlated with vegetative changes. I also monitored inundation depth, growth, and phenological response of individual stands of reed canarygrass during the 2004 growing season. Close

• 15. [Article] Future Flooding Impacts on Transportation Infrastructure and Traffic Patterns Resulting from Climate Change

  This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland metropolitan area. We used ensemble climate change ...

  Citation × Citation Citation Abstract Copy Title: Future Flooding Impacts on Transportation Infrastructure and Traffic Patterns Resulting from Climate Change Author: Chang, Heejun, Lafrenz, Martin, Jung, Il-Won, Figliozzi, Miguel A., Melgoza, Rolando, Ruelas, David, Platman, Deena, Pederson, Cindy Year: 2011 This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland metropolitan area. We used ensemble climate change scenarios, a hydrologic model, stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission scenarios and eight general circulation models. The Precipitation-Runoff Modeling System was calibrated and validated for the period 1988-2006, and simulated for determining the probability of floods from 2020-2049. We surveyed stream cross sections at five road crossings for stream channel geometry and determined floodwater surface elevations using the HEC-RAS model. Four of the surveyed bridges and roadways were lower in elevation than the current 100-year floodwater surface elevation, leading to relatively frequent nuisance flooding. These roadway flooding events will become more frequent under some climate change scenarios in the future, but climate change impacts will depend on local geomorphic conditions. While vehicle miles traveled were not significantly affected by road closure, vehicle-hours delay demonstrated a greater impact from road closures, increasing by 10 percent in the Fanno Creek area. Results indicate that any cost analysis is extremely sensitive to the occurrence of human fatalities or injuries and fairly insensitive to delay costs. In addition, this research presents a comprehensive classification of flooding costs, identifies preventative measures, and makes short- and long-term recommendations. Our research demonstrated the usefulness of the integration of top-down and bottom-up approaches in climate change impact assessment, and the need for spatially explicit modeling and participatory planning in flood management and transportation planning under increasing climate uncertainty. Title: Future Flooding Impacts on Transportation Infrastructure and Traffic Patterns Resulting from Climate Change Author: Chang, Heejun, Lafrenz, Martin, Jung, Il-Won, Figliozzi, Miguel A., Melgoza, Rolando, Ruelas, David, Platman, Deena, Pederson, Cindy Year: 2011 This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland metropolitan area. We used ensemble climate change scenarios, a hydrologic model, stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission scenarios and eight general circulation models. The Precipitation-Runoff Modeling System was calibrated and validated for the period 1988-2006, and simulated for determining the probability of floods from 2020-2049. We surveyed stream cross sections at five road crossings for stream channel geometry and determined floodwater surface elevations using the HEC-RAS model. Four of the surveyed bridges and roadways were lower in elevation than the current 100-year floodwater surface elevation, leading to relatively frequent nuisance flooding. These roadway flooding events will become more frequent under some climate change scenarios in the future, but climate change impacts will depend on local geomorphic conditions. While vehicle miles traveled were not significantly affected by road closure, vehicle-hours delay demonstrated a greater impact from road closures, increasing by 10 percent in the Fanno Creek area. Results indicate that any cost analysis is extremely sensitive to the occurrence of human fatalities or injuries and fairly insensitive to delay costs. In addition, this research presents a comprehensive classification of flooding costs, identifies preventative measures, and makes short- and long-term recommendations. Our research demonstrated the usefulness of the integration of top-down and bottom-up approaches in climate change impact assessment, and the need for spatially explicit modeling and participatory planning in flood management and transportation planning under increasing climate uncertainty. Close

• 16. [Article] Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2

  The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, ...

  Citation × Citation Citation Abstract Copy Title: Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2 Author: Van Glubt, Sarah Year: 2017 The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, exists within five counties, and flows through agricultural, residential, industrial, and forest land areas. Four major rivers discharge to the Chehalis River, as well as many smaller creeks, five wastewater treatment plants, and groundwater flows. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia, with severe consequences for property, safety and transportation. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen, and has had multiple water quality and Total Maximum Daily Load studies beginning in 1990. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure's impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed. This involved developing meteorological data, riparian shading data, and flow, temperature, water quality records for all tributaries during the calibration period of January 1, 2013 to December 31, 2014. System cross-sectional geometry data were also required for the model grid. Because of the short travel time in the river, the model was sensitive to boundary condition data, wind speed, bathymetry, nutrient kinetics, and algae, epiphyton, and zooplankton kinetics. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures also showed impacts to river temperature and water quality. Structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. As this research continues improvements will be made, particularly to temperature and water quality constituents. Additional data for the system would be beneficial to this process. Model predictions of temperature were sensitive to meteorological data, including cloud cover, which were largely estimated based on solar radiation. Additional meteorological data throughout the basin would be useful to temperature results. Temperature results were also sensitive to the model bathymetry, and additional investigations into segments widths and water depths may improve temperature predictions. Water quality constituent data were largely lacking for the system. Many estimation techniques and approximations were used for input water quality constituents for the model upstream boundary and tributaries when little or no data were available, introducing uncertainty to the model. It was not possible to calibrate pH to field data because alkalinity data were essentially unavailable. However, other constituents had good agreement between model predictions and field data, including dissolved oxygen, nitrates, total phosphorus, and total suspended solids. Title: Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2 Author: Van Glubt, Sarah Year: 2017 The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, exists within five counties, and flows through agricultural, residential, industrial, and forest land areas. Four major rivers discharge to the Chehalis River, as well as many smaller creeks, five wastewater treatment plants, and groundwater flows. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia, with severe consequences for property, safety and transportation. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen, and has had multiple water quality and Total Maximum Daily Load studies beginning in 1990. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure's impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed. This involved developing meteorological data, riparian shading data, and flow, temperature, water quality records for all tributaries during the calibration period of January 1, 2013 to December 31, 2014. System cross-sectional geometry data were also required for the model grid. Because of the short travel time in the river, the model was sensitive to boundary condition data, wind speed, bathymetry, nutrient kinetics, and algae, epiphyton, and zooplankton kinetics. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures also showed impacts to river temperature and water quality. Structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. As this research continues improvements will be made, particularly to temperature and water quality constituents. Additional data for the system would be beneficial to this process. Model predictions of temperature were sensitive to meteorological data, including cloud cover, which were largely estimated based on solar radiation. Additional meteorological data throughout the basin would be useful to temperature results. Temperature results were also sensitive to the model bathymetry, and additional investigations into segments widths and water depths may improve temperature predictions. Water quality constituent data were largely lacking for the system. Many estimation techniques and approximations were used for input water quality constituents for the model upstream boundary and tributaries when little or no data were available, introducing uncertainty to the model. It was not possible to calibrate pH to field data because alkalinity data were essentially unavailable. However, other constituents had good agreement between model predictions and field data, including dissolved oxygen, nitrates, total phosphorus, and total suspended solids. Close

• 17. [Article] Tidal Asymmetry in an Estuarine Pycnocline 2. Transport

  Flood currents in shallow estuaries are driven by an along-channel barotropic and baroclinic pressure gradient that increases monotonically toward the bottom, while friction retards near-bottom currents. ...

  Citation × Citation Citation Abstract Copy Title: Tidal Asymmetry in an Estuarine Pycnocline 2. Transport Author: Jay, David A., Cudaback, Cynthia N. Year: 2001 Flood currents in shallow estuaries are driven by an along-channel barotropic and baroclinic pressure gradient that increases monotonically toward the bottom, while friction retards near-bottom currents. Therefore, in many estuaries there is a middepth maximum in flood currents. We explore this phenomenon using a simple three-layer model in which each layer has vertically uniform currents and constant density. In this model the middle layer is of intermediate density and grows by shear-induced entrainment from the other two layers. This very simple model produces a middepth maximum in flood currents and simulates observed currents in the Columbia River entrance channel within about 10%. There is good qualitative agreement between model salinity transport and observed transport. The model pycnocline rises and falls tidally, in phase with the observed pycnocline, although pycnocline depth and thickness are better simulated using results from a two-layer model Title: Tidal Asymmetry in an Estuarine Pycnocline 2. Transport Author: Jay, David A., Cudaback, Cynthia N. Year: 2001 Flood currents in shallow estuaries are driven by an along-channel barotropic and baroclinic pressure gradient that increases monotonically toward the bottom, while friction retards near-bottom currents. Therefore, in many estuaries there is a middepth maximum in flood currents. We explore this phenomenon using a simple three-layer model in which each layer has vertically uniform currents and constant density. In this model the middle layer is of intermediate density and grows by shear-induced entrainment from the other two layers. This very simple model produces a middepth maximum in flood currents and simulates observed currents in the Columbia River entrance channel within about 10%. There is good qualitative agreement between model salinity transport and observed transport. The model pycnocline rises and falls tidally, in phase with the observed pycnocline, although pycnocline depth and thickness are better simulated using results from a two-layer model Close

• 18. [Article] Effects of urbanization on the hydrologic regime of Johnson Creek, Portland, Oregon

  The Johnson Creek watershed, Portland, Oregon, has undergone urbanization at an increasing rate. Excessive flooding has occurred in the lower portions of the watershed, resulting in an estimated 1.5 million ...

  Citation × Citation Citation Abstract Copy Title: Effects of urbanization on the hydrologic regime of Johnson Creek, Portland, Oregon Author: Clement, William Vandewater Year: 1984 The Johnson Creek watershed, Portland, Oregon, has undergone urbanization at an increasing rate. Excessive flooding has occurred in the lower portions of the watershed, resulting in an estimated 1.5 million dollars worth of flood losses annually. In attempts to mitigate the flooding damages millions of dollars have been spent to channelize the creek, and over 200 thousand dollars has been spent during the last 20 years on preliminary feasibility studies alone. The author saw a need to verify that there has been a change in the rainfall-runoff relationships in the upper Johnson Creek basin since 1941 and to quantify this change through the analysis of key hydrologic parameters. To accomplish this , extensive background research was conducted to gather as much extant information as possible about the climatic and physiographic characteristics that affect the basin hydrology. The watershed was found to have many distinct physiographic sub-areas comprised of different underlying geology, soils, geomorphic areas, slopes, vegetation patterns, and land use types that result in a complex interaction between the watershed input {precipitation) and the watershed output (runoff at the stream gage). Title: Effects of urbanization on the hydrologic regime of Johnson Creek, Portland, Oregon Author: Clement, William Vandewater Year: 1984 The Johnson Creek watershed, Portland, Oregon, has undergone urbanization at an increasing rate. Excessive flooding has occurred in the lower portions of the watershed, resulting in an estimated 1.5 million dollars worth of flood losses annually. In attempts to mitigate the flooding damages millions of dollars have been spent to channelize the creek, and over 200 thousand dollars has been spent during the last 20 years on preliminary feasibility studies alone. The author saw a need to verify that there has been a change in the rainfall-runoff relationships in the upper Johnson Creek basin since 1941 and to quantify this change through the analysis of key hydrologic parameters. To accomplish this , extensive background research was conducted to gather as much extant information as possible about the climatic and physiographic characteristics that affect the basin hydrology. The watershed was found to have many distinct physiographic sub-areas comprised of different underlying geology, soils, geomorphic areas, slopes, vegetation patterns, and land use types that result in a complex interaction between the watershed input {precipitation) and the watershed output (runoff at the stream gage). Close

• 19. [Article] Floodplains: Balancing Nature and Human Needs

  For countless years, the interaction between climatic conditions and water flow has forged the rolling hills and rivers in the metroscape. The floods that forced a deluge of water down the Columbia River ...

  Citation × Citation Citation Abstract Copy Title: Floodplains: Balancing Nature and Human Needs Author: Shandas, Vivek, Merrick, Meg Year: 2008 For countless years, the interaction between climatic conditions and water flow has forged the rolling hills and rivers in the metroscape. The floods that forced a deluge of water down the Columbia River between 13 and 17 thousand years ago established the fertile and absorptive landscape of the Willamette Valley. The lush vegetation controlled the regional climate and stabilized the soils, while the thirsty wetlands reduced flood potential, provided habitat, and purified the water. Over geological time, these natural processes have created ideal conditions for humans. The Pacific Northwest was home to some of the most densely populated communities of Native Americans, due partly to mild climate, plentiful water, and abundant sources of food and shelter. In the 19th century, Anglo settlers flooded the region for the same amenities, which continues to create ideal conditions for all that the region is known for today, including hiking, kayaking, and sailing - not to mention the provision of climate, topography, and fertile soils for growing some of the world?s best wines! Land surveys from the 1860s suggest that the current form of the metroscape started to take shape at the end of the 19th century. The conifers, alders, and maples that covered the region were slowly removed to make way for new urban settlements, and wetlands were drained to create farms and agricultural areas. In this atlas, we journey 140 years into the past to examine how and where the metroscape has changed. Our aim is to illustrate historic flooding of the region, and ponder what changes might mean to its future. Title: Floodplains: Balancing Nature and Human Needs Author: Shandas, Vivek, Merrick, Meg Year: 2008 For countless years, the interaction between climatic conditions and water flow has forged the rolling hills and rivers in the metroscape. The floods that forced a deluge of water down the Columbia River between 13 and 17 thousand years ago established the fertile and absorptive landscape of the Willamette Valley. The lush vegetation controlled the regional climate and stabilized the soils, while the thirsty wetlands reduced flood potential, provided habitat, and purified the water. Over geological time, these natural processes have created ideal conditions for humans. The Pacific Northwest was home to some of the most densely populated communities of Native Americans, due partly to mild climate, plentiful water, and abundant sources of food and shelter. In the 19th century, Anglo settlers flooded the region for the same amenities, which continues to create ideal conditions for all that the region is known for today, including hiking, kayaking, and sailing - not to mention the provision of climate, topography, and fertile soils for growing some of the world?s best wines! Land surveys from the 1860s suggest that the current form of the metroscape started to take shape at the end of the 19th century. The conifers, alders, and maples that covered the region were slowly removed to make way for new urban settlements, and wetlands were drained to create farms and agricultural areas. In this atlas, we journey 140 years into the past to examine how and where the metroscape has changed. Our aim is to illustrate historic flooding of the region, and ponder what changes might mean to its future. Close

• 20. [Article] Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed

  Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative ...

  Citation × Citation Citation Abstract Copy Title: Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed Author: Hong, Change-Yu, Chung, Eun-Sung Year: 2016 Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative governance definitely requires an active participatory decision-making process that reflects citizens’ preferences. Citizen preference also tends to substantially change with life pattern and life quality. These shifts can be caused by slight variations in both social priorities and personal preferences for SWM. Therefore, collaborative water governance must be frequently renewed in response to citizens’ values through the participatory framework. The An’yang Stream in South Korea is generally regarded as a representative urban stream restoration case that has been successfully led by collaborative governance. By conducting individual surveys with citizens on-site, this study addresses how citizens’ preferences of the stream’s management have changed between 2005 and 2015. In addition, this study used three quantitative hydrologic vulnerability indices: potential flood damage (PFD), potential streamflow depletion (PSD), and potential water quality deterioration (PWQD). They can spatially quantify citizen preference using the Analytic Hierarchy Process (AHP), which can systematically derive citizens’ subjective relative-weighted preferences. In the end, this study identified critical differences in priorities in regard to vulnerable areas between in 2005 and in 2015. Title: Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed Author: Hong, Change-Yu, Chung, Eun-Sung Year: 2016 Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative governance definitely requires an active participatory decision-making process that reflects citizens’ preferences. Citizen preference also tends to substantially change with life pattern and life quality. These shifts can be caused by slight variations in both social priorities and personal preferences for SWM. Therefore, collaborative water governance must be frequently renewed in response to citizens’ values through the participatory framework. The An’yang Stream in South Korea is generally regarded as a representative urban stream restoration case that has been successfully led by collaborative governance. By conducting individual surveys with citizens on-site, this study addresses how citizens’ preferences of the stream’s management have changed between 2005 and 2015. In addition, this study used three quantitative hydrologic vulnerability indices: potential flood damage (PFD), potential streamflow depletion (PSD), and potential water quality deterioration (PWQD). They can spatially quantify citizen preference using the Analytic Hierarchy Process (AHP), which can systematically derive citizens’ subjective relative-weighted preferences. In the end, this study identified critical differences in priorities in regard to vulnerable areas between in 2005 and in 2015. Close