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• 1. [Article] Potential Impacts of Climate Change on Flood-Induced Travel Disruptions: A Case Study of Portland, Oregon, USA

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

  Citation × Citation Citation Abstract Copy Title: Potential Impacts of Climate Change on Flood-Induced Travel Disruptions: A Case Study of Portland, Oregon, USA Author: Chang, Heejun, Lafrenz, Martin, Jung, Il-won, Figliozzi, Miguel, Platman, Deena, Pederson, Cindy Year: 2010 This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland, Oregon, metropolitan area. We used ensemble climate change scenarios, a hydrologic model, a 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 historical period of 1988 and 2006 and simulated for determining the probability of floods for 2020 through 2049. We surveyed stream cross-sections at five road crossings for stream channel geometry and determined flood water surface elevations using the Hydrologic Engineering Centers River Analysis System (HEC-RAS) model. Four of the surveyed bridges and roadways were lower in elevation than the current 100-year flood water 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. Whereas vehicle miles traveled was 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. 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: Potential Impacts of Climate Change on Flood-Induced Travel Disruptions: A Case Study of Portland, Oregon, USA Author: Chang, Heejun, Lafrenz, Martin, Jung, Il-won, Figliozzi, Miguel, Platman, Deena, Pederson, Cindy Year: 2010 This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland, Oregon, metropolitan area. We used ensemble climate change scenarios, a hydrologic model, a 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 historical period of 1988 and 2006 and simulated for determining the probability of floods for 2020 through 2049. We surveyed stream cross-sections at five road crossings for stream channel geometry and determined flood water surface elevations using the Hydrologic Engineering Centers River Analysis System (HEC-RAS) model. Four of the surveyed bridges and roadways were lower in elevation than the current 100-year flood water 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. Whereas vehicle miles traveled was 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. 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

• 2. [Article] Analysis of Landsat Satellite Data to Monitor Water Quality Parameters in Tenmile Lake, Oregon

  The health of North and South Tenmile Lakes in coastal Oregon has declined since the introduction of invasive species of fish and plant life in the 1920s. The lakes are now on the Federal Clean Water Act ...

  Citation × Citation Citation Abstract Copy Title: Analysis of Landsat Satellite Data to Monitor Water Quality Parameters in Tenmile Lake, Oregon Author: Waxter, Michael T. Year: 2014 The health of North and South Tenmile Lakes in coastal Oregon has declined since the introduction of invasive species of fish and plant life in the 1920s. The lakes are now on the Federal Clean Water Act list of impaired water bodies due, in part, to a lack of dissolved oxygen and Hazardous Algae Blooms (HAB) blooms that occur during June through September. In this report we discuss the possibility of detecting and monitoring these blooms using satellite measurements of water surface color. In-situ measurements obtained from the Tenmile Lakes Basin Partnership were used to calibrate reflectance from the Thematic Mapper on the Landsat 5 satellite. Results show a good linear correlation between turbidity and radiance, which are inversely related in algal dominated lakes. Additionally, a correlation between biovolume and reflectance was obtained. Spatial patterns of turbidity and biovolume are observed, with large concentrations observed in lake areas with large residence times. The comparatively lowest concentrations are observed along the probable pathway of cleaner water input by creeks into the lake. However, the ability to predict turbidity and biovolume from satellite reflectance data is currently complicated by the lack of coincident in-situ and satellite data, and the limited number of spectral bands available to separate turbidity from different species of bacteria and algae. Title: Analysis of Landsat Satellite Data to Monitor Water Quality Parameters in Tenmile Lake, Oregon Author: Waxter, Michael T. Year: 2014 The health of North and South Tenmile Lakes in coastal Oregon has declined since the introduction of invasive species of fish and plant life in the 1920s. The lakes are now on the Federal Clean Water Act list of impaired water bodies due, in part, to a lack of dissolved oxygen and Hazardous Algae Blooms (HAB) blooms that occur during June through September. In this report we discuss the possibility of detecting and monitoring these blooms using satellite measurements of water surface color. In-situ measurements obtained from the Tenmile Lakes Basin Partnership were used to calibrate reflectance from the Thematic Mapper on the Landsat 5 satellite. Results show a good linear correlation between turbidity and radiance, which are inversely related in algal dominated lakes. Additionally, a correlation between biovolume and reflectance was obtained. Spatial patterns of turbidity and biovolume are observed, with large concentrations observed in lake areas with large residence times. The comparatively lowest concentrations are observed along the probable pathway of cleaner water input by creeks into the lake. However, the ability to predict turbidity and biovolume from satellite reflectance data is currently complicated by the lack of coincident in-situ and satellite data, and the limited number of spectral bands available to separate turbidity from different species of bacteria and algae. Close