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• 31. [Article] Long-Term Exposure to Fluoxetine Reduces Growth and Reproductive Potential in the Dominant Rocky Intertidal Mussel, Mytilus californianus

  Environmental stressors shape community composition and ecosystem functioning. Contaminants such as pharmaceuticals are of increasing concern as an environmental stressor due to their persistence in surface ...

  Citation × Citation Citation Abstract Copy Title: Long-Term Exposure to Fluoxetine Reduces Growth and Reproductive Potential in the Dominant Rocky Intertidal Mussel, Mytilus californianus Author: Peters, Joseph R., Granek, Elise F. Year: 2016 Environmental stressors shape community composition and ecosystem functioning. Contaminants such as pharmaceuticals are of increasing concern as an environmental stressor due to their persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations; and examination of whole organism effects are necessary to identify potential community-level consequences in estuarine and marine ecosystems. We conducted a long-term exposure study (107 days) with the anti-depressant pharmaceutical, fluoxetine (the active constituent in Prozac®) to determine whether minimal concentrations affected whole organism metrics in the California mussel, Mytilus californianus. We measured algal clearance rates, mussel growth, and the gonadosomatic index, a measure of reproductive health. We found that fluoxetine negatively affects all measured characteristics, however many effects were mediated by length of exposure. Our results fill an important data gap, highlighting organism-level effects of chronic exposure periods; such data more explicitly identify the overall impacts of pharmaceuticals and other contaminants on marine communities and ecosystems. Title: Long-Term Exposure to Fluoxetine Reduces Growth and Reproductive Potential in the Dominant Rocky Intertidal Mussel, Mytilus californianus Author: Peters, Joseph R., Granek, Elise F. Year: 2016 Environmental stressors shape community composition and ecosystem functioning. Contaminants such as pharmaceuticals are of increasing concern as an environmental stressor due to their persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations; and examination of whole organism effects are necessary to identify potential community-level consequences in estuarine and marine ecosystems. We conducted a long-term exposure study (107 days) with the anti-depressant pharmaceutical, fluoxetine (the active constituent in Prozac®) to determine whether minimal concentrations affected whole organism metrics in the California mussel, Mytilus californianus. We measured algal clearance rates, mussel growth, and the gonadosomatic index, a measure of reproductive health. We found that fluoxetine negatively affects all measured characteristics, however many effects were mediated by length of exposure. Our results fill an important data gap, highlighting organism-level effects of chronic exposure periods; such data more explicitly identify the overall impacts of pharmaceuticals and other contaminants on marine communities and ecosystems. Close

• 32. [Article] Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon

  In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, ...

  Citation × Citation Citation Abstract Copy Title: Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2013 In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, Carex aquatilis var. aquatilis, Carex nebrascensis, Carex pellita, Carex praegracilis, Carex sheldonii, Distichlis spicata, Juncus balticus, Leymus triticoides, Phalaris arundinacea, and Sparganium eurycarpum. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores help to place the plant associations within gradients in soil moisture and alkalinity. The Alopecurus pratensis and Phalaris arundinacea associations are dominated by exotic, invasive species and appear to be outcompeting native plant associations. Phases of the Carex praegracilis association appear to be replaced by the Alopecurus pratensis association, while the Carex pellita, Juncus balticus, and Leymus triticoides associations may be replaced by the Phalaris arundinacea association. The Carex aquatilis and Sparganium eurycarpum associations were undersampled and provide only an estimate of composition. Most associations are consistent with what has been included in the National Vegetation Classification. Title: Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2013 In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, Carex aquatilis var. aquatilis, Carex nebrascensis, Carex pellita, Carex praegracilis, Carex sheldonii, Distichlis spicata, Juncus balticus, Leymus triticoides, Phalaris arundinacea, and Sparganium eurycarpum. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores help to place the plant associations within gradients in soil moisture and alkalinity. The Alopecurus pratensis and Phalaris arundinacea associations are dominated by exotic, invasive species and appear to be outcompeting native plant associations. Phases of the Carex praegracilis association appear to be replaced by the Alopecurus pratensis association, while the Carex pellita, Juncus balticus, and Leymus triticoides associations may be replaced by the Phalaris arundinacea association. The Carex aquatilis and Sparganium eurycarpum associations were undersampled and provide only an estimate of composition. Most associations are consistent with what has been included in the National Vegetation Classification. Close

• 33. [Article] Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon

  This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double ...

  Citation × Citation Citation Abstract Copy Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2016 This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double O was wetter and more alkaline than wet meadows sampled at the south end of the refuge in 2012 and 2013 (Christy 2014), data from the Double O Unit were analyzed and summarized separately. A total of 83 plots were sampled in 2015, and analysis of the data identified 14 plant associations: Alopecurus aequalis - Juncus balticus, Alopecurus pratensis - Potentilla anserina, Carex praegracilis - Juncus balticus, Cicuta douglasii - Carex nebrascensis, Distichlis spicata - Amphiscirpus nevadensis, Distichlis spicata - Nitrophila occidentalis, Eleocharis palustris - Juncus balticus, Eleocharis rostellata, Juncus balticus - Glaux maritima, Hippuris vulgaris - Triglochin maritima, Leymus triticoides - Juncus balticus, Schoenoplectus americanus, Spartina gracilis, and Triglochin maritima. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores and species composition help to place the plant associations within gradients in soil moisture and alkalinity. Seven of the 14 plant associations are listed in the International Vegetation Classification, and the remaining types are provisional Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2016 This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double O was wetter and more alkaline than wet meadows sampled at the south end of the refuge in 2012 and 2013 (Christy 2014), data from the Double O Unit were analyzed and summarized separately. A total of 83 plots were sampled in 2015, and analysis of the data identified 14 plant associations: Alopecurus aequalis - Juncus balticus, Alopecurus pratensis - Potentilla anserina, Carex praegracilis - Juncus balticus, Cicuta douglasii - Carex nebrascensis, Distichlis spicata - Amphiscirpus nevadensis, Distichlis spicata - Nitrophila occidentalis, Eleocharis palustris - Juncus balticus, Eleocharis rostellata, Juncus balticus - Glaux maritima, Hippuris vulgaris - Triglochin maritima, Leymus triticoides - Juncus balticus, Schoenoplectus americanus, Spartina gracilis, and Triglochin maritima. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores and species composition help to place the plant associations within gradients in soil moisture and alkalinity. Seven of the 14 plant associations are listed in the International Vegetation Classification, and the remaining types are provisional Close

• 34. [Article] Mapping the Nonstationary Internal Tide with Satellite Altimetry

  t Temporal variability of the internal tide has been inferred from the 23 year long combined records of the TOPEX/Poseidon, Jason-1, and Jason-2 satellite altimeters by combining harmonic analysis with ...

  Citation × Citation Citation Abstract Copy Title: Mapping the Nonstationary Internal Tide with Satellite Altimetry Author: Zaron, Edward Year: 2017 t Temporal variability of the internal tide has been inferred from the 23 year long combined records of the TOPEX/Poseidon, Jason-1, and Jason-2 satellite altimeters by combining harmonic analysis with an analysis of along-track wavenumber spectra of sea-surface height (SSH). Conventional harmonic analysis is first applied to estimate and remove the stationary components of the tide at each point along the reference ground tracks. The wavenumber spectrum of the residual SSH is then computed, and the variance in a neighborhood around the wavenumber of the mode-1 baroclinic M2 tide is interpreted as the sum of noise, broadband nontidal processes, and the nonstationary tide. At many sites a bump in the spectrum associated with the internal tide is noted, and an empirical model for the noise and nontidal processes is used to estimate the nonstationary semidiurnal tidal variance. The results indicate a spatially inhomogeneous pattern of tidal variability. Nonstationary tides are larger than stationary tides throughout much of the equatorial Pacific and Indian Oceans Title: Mapping the Nonstationary Internal Tide with Satellite Altimetry Author: Zaron, Edward Year: 2017 t Temporal variability of the internal tide has been inferred from the 23 year long combined records of the TOPEX/Poseidon, Jason-1, and Jason-2 satellite altimeters by combining harmonic analysis with an analysis of along-track wavenumber spectra of sea-surface height (SSH). Conventional harmonic analysis is first applied to estimate and remove the stationary components of the tide at each point along the reference ground tracks. The wavenumber spectrum of the residual SSH is then computed, and the variance in a neighborhood around the wavenumber of the mode-1 baroclinic M2 tide is interpreted as the sum of noise, broadband nontidal processes, and the nonstationary tide. At many sites a bump in the spectrum associated with the internal tide is noted, and an empirical model for the noise and nontidal processes is used to estimate the nonstationary semidiurnal tidal variance. The results indicate a spatially inhomogeneous pattern of tidal variability. Nonstationary tides are larger than stationary tides throughout much of the equatorial Pacific and Indian Oceans Close

• 35. [Article] Non-Stationary Internal Tides Observed with Satellite Altimetry

  Temporal variability of the internal tide is inferred from a 17-year combined record of Topex/Poseidon and Jason satellite altimeters. A global sampling of along-track sea-surface height wavenumber spectra ...

  Citation × Citation Citation Abstract Copy Title: Non-Stationary Internal Tides Observed with Satellite Altimetry Author: Ray, R. D., Zaron, Edward D. Year: 2011 Temporal variability of the internal tide is inferred from a 17-year combined record of Topex/Poseidon and Jason satellite altimeters. A global sampling of along-track sea-surface height wavenumber spectra finds that non-stationary variance is generally 25% or less of the average variance at wavenumbers characteristic of mode-1 tidal internal waves. With some exceptions the non-stationary variance does not exceed 0.25 cm2. The mode-2 signal, where detectable, contains a larger fraction of non-stationary variance, typically 50% or more. Temporal subsetting of the data reveals interannual variability barely significant compared with tidal estimation error from 3-year records. Comparison of summer vs. winter conditions shows only one region of noteworthy seasonal changes, the northern South China Sea. Implications for the anticipated SWOT altimeter mission are briefly discussed. Title: Non-Stationary Internal Tides Observed with Satellite Altimetry Author: Ray, R. D., Zaron, Edward D. Year: 2011 Temporal variability of the internal tide is inferred from a 17-year combined record of Topex/Poseidon and Jason satellite altimeters. A global sampling of along-track sea-surface height wavenumber spectra finds that non-stationary variance is generally 25% or less of the average variance at wavenumbers characteristic of mode-1 tidal internal waves. With some exceptions the non-stationary variance does not exceed 0.25 cm2. The mode-2 signal, where detectable, contains a larger fraction of non-stationary variance, typically 50% or more. Temporal subsetting of the data reveals interannual variability barely significant compared with tidal estimation error from 3-year records. Comparison of summer vs. winter conditions shows only one region of noteworthy seasonal changes, the northern South China Sea. Implications for the anticipated SWOT altimeter mission are briefly discussed. Close

• 36. [Article] Regional Models of Internal Tides

  Internal tides are ubiquitous in the ocean, and they play an important role in a range of ocean processes, for example, particle dispersal, acoustics, and vertical buoyancy flux. The wavelength of internal ...

  Citation × Citation Citation Abstract Copy Title: Regional Models of Internal Tides Author: Carter, Glenn S., Fringer, Oliver B., Zaron, Edward D. Year: 2012 Internal tides are ubiquitous in the ocean, and they play an important role in a range of ocean processes, for example, particle dispersal, acoustics, and vertical buoyancy flux. The wavelength of internal tides can be as much as 250 km in the open ocean, but as the generation of these tides depends on the angle between the depth-averaged current and the topography, there can be considerable local spatial variability. This range of scales makes it difficult to develop a comprehensive understanding of the processes involved from observations alone. Regional numerical modeling provides a way to study the generation and early propagation of internal tides at high resolution. Here, we review the role that regional internal tide models, primarily hydrostatic models, can play in increasing our understanding. Title: Regional Models of Internal Tides Author: Carter, Glenn S., Fringer, Oliver B., Zaron, Edward D. Year: 2012 Internal tides are ubiquitous in the ocean, and they play an important role in a range of ocean processes, for example, particle dispersal, acoustics, and vertical buoyancy flux. The wavelength of internal tides can be as much as 250 km in the open ocean, but as the generation of these tides depends on the angle between the depth-averaged current and the topography, there can be considerable local spatial variability. This range of scales makes it difficult to develop a comprehensive understanding of the processes involved from observations alone. Regional numerical modeling provides a way to study the generation and early propagation of internal tides at high resolution. Here, we review the role that regional internal tide models, primarily hydrostatic models, can play in increasing our understanding. Close

• 37. [Article] Infrared-Based Measurements of Velocity, Turbulent Kinetic Energy, and Dissipation at the Water Surface in a Tidal River

  Thermal infrared (IR) based particle image velocimetry (PIV) is used to measure the evolution of velocity, turbulent kinetic energy (TKE), and the TKE dissipation rate at the water surface in the tidally ...

  Citation × Citation Citation Abstract Copy Title: Infrared-Based Measurements of Velocity, Turbulent Kinetic Energy, and Dissipation at the Water Surface in a Tidal River Author: Chickadel, C. Chris, Talke, Stefan A., Horner-Devine, Alexander R., Jessup, Andrew T. Year: 2011 Thermal infrared (IR) based particle image velocimetry (PIV) is used to measure the evolution of velocity, turbulent kinetic energy (TKE), and the TKE dissipation rate at the water surface in the tidally influenced Snohomish River. Patterns of temperature variability in the IR imagery arise from disruption of the cool skin layer and are used to estimate the 2D velocity field. Comparisons of IR based PIV mean velocity made against a collocated acoustic velocimeter demonstrate high correlation (r2 > 0.9). Over a tidal period, surface TKE computed from the IR velocity varies from 10-4 J·kg-1 to 3x10-3 J·kg-1, with an average difference from the in situ measurements of 8%. IR-derived TKE dissipation rates vary from approximately 3x10-6 W·kg-1 to 2x10-4 W·kg-1 at peak ebb, agreeing on average to within 7% of the in situ velocimeter results. Infrared-based PIV provides detailed measurements of previously inaccessible surface flow and turbulence statistics. Title: Infrared-Based Measurements of Velocity, Turbulent Kinetic Energy, and Dissipation at the Water Surface in a Tidal River Author: Chickadel, C. Chris, Talke, Stefan A., Horner-Devine, Alexander R., Jessup, Andrew T. Year: 2011 Thermal infrared (IR) based particle image velocimetry (PIV) is used to measure the evolution of velocity, turbulent kinetic energy (TKE), and the TKE dissipation rate at the water surface in the tidally influenced Snohomish River. Patterns of temperature variability in the IR imagery arise from disruption of the cool skin layer and are used to estimate the 2D velocity field. Comparisons of IR based PIV mean velocity made against a collocated acoustic velocimeter demonstrate high correlation (r2 > 0.9). Over a tidal period, surface TKE computed from the IR velocity varies from 10-4 J·kg-1 to 3x10-3 J·kg-1, with an average difference from the in situ measurements of 8%. IR-derived TKE dissipation rates vary from approximately 3x10-6 W·kg-1 to 2x10-4 W·kg-1 at peak ebb, agreeing on average to within 7% of the in situ velocimeter results. Infrared-based PIV provides detailed measurements of previously inaccessible surface flow and turbulence statistics. Close

• 38. [Article] Using Maps to Accelerate Social Movements and Reclaim Place

  Jennifer Veilleux is a geographer focused on the water security of international rivers. Jennifer earned her Ph.D. in Geography from Oregon State University. She has a background in surface and subsurface ...

  Citation × Citation Citation Abstract Copy Title: Using Maps to Accelerate Social Movements and Reclaim Place Author: Veilleux, Jennifer Year: 2017 Jennifer Veilleux is a geographer focused on the water security of international rivers. Jennifer earned her Ph.D. in Geography from Oregon State University. She has a background in surface and subsurface water science and has researched, published, and lectured on threats to humans and the environment from water development in the Nile, Mekong, Missouri, among other basins throughout the world. In addition to scholarship, Veilleux uses maps, infographics, and satellite imagery through social media to highlight spatial relationships of environmental justice and human rights issues as relates to water. As a Postdoctoral Associate with the Steven J. Green School of International and Public Affairs at Florida International University, Jennifer does research and analysis of the hydropolitics of some of the world’s major rivers. Title: Using Maps to Accelerate Social Movements and Reclaim Place Author: Veilleux, Jennifer Year: 2017 Jennifer Veilleux is a geographer focused on the water security of international rivers. Jennifer earned her Ph.D. in Geography from Oregon State University. She has a background in surface and subsurface water science and has researched, published, and lectured on threats to humans and the environment from water development in the Nile, Mekong, Missouri, among other basins throughout the world. In addition to scholarship, Veilleux uses maps, infographics, and satellite imagery through social media to highlight spatial relationships of environmental justice and human rights issues as relates to water. As a Postdoctoral Associate with the Steven J. Green School of International and Public Affairs at Florida International University, Jennifer does research and analysis of the hydropolitics of some of the world’s major rivers. Close

• 39. [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

• 40. [Article] Assessing a Fluorescence Spectroscopy Method for In-Situ Microbial Drinking Water Quality

  Waterborne disease is a significant contributor to the global burden of disease, in particular among high-risk populations in developing nations. State-of-the-art methods for the enumeration of microbial ...

  Citation × Citation Citation Abstract Copy Title: Assessing a Fluorescence Spectroscopy Method for In-Situ Microbial Drinking Water Quality Author: Sharpe, Taylor Jeffery Year: 2017 Waterborne disease is a significant contributor to the global burden of disease, in particular among high-risk populations in developing nations. State-of-the-art methods for the enumeration of microbial pathogens in drinking water sources have important limitations, including high initial cost, 24-48 hour delays in results, high staffing and facility requirements, and training requirements which all become especially problematic in the developing nation context. A number of alternative approaches to microbial water quality testing have been proposed, with the goal of decreasing the required testing time, decreasing overall costs, leveraging appropriate technology approaches, or improving sensitivity or specificity of the water quality testing method. One approach that may offer solutions to some of these limitations involves the deployment of sensor networks using fluorescent spectroscopy to detect intrinsic protein fluorescence in water samples as a proxy for microbial activity. In recent years, a number of researchers have found significant and meaningful correlations between indicator bacteria species and the protein fluorescence of drinking water samples. Additionally, advances in the semiconductor industry could be used to drive down the cost of such sensors. This technology may also be extensible to other water quality parameters, including dissolved organic matter or the presence of fluorescent pollutants. In this thesis, a literature review describes the fundamentals of fluorescence spectroscopy, historical and recent work regarding the fluorescence of the amino acid tryptophan and associated bacterial fluorescence, possible mechanisms for this association, and potential applications of this technology for drinking water quality monitoring and waste water process control. Extensibility of the technology is also discussed. Next, experimental methodology in reproduction of similar results is described. Samples were taken from seven (7) surface water sources and tested using membrane filtration and an off-the-shelf fluorescence spectrometer to help examine the association between the presence of indicator bacteria and the tryptophan fluorescence of the water sample. The results, showing an association of R2 = 0.560, are compared to the results of recent similar experiments. Finally, two prototypes are described, including their design requirements and data from prototype testing. The results of the testing are briefly discussed, and next steps are outlined with the goal of developing a low-cost, in-situ microbial water quality sensor using fluorescence spectroscopy principles. Title: Assessing a Fluorescence Spectroscopy Method for In-Situ Microbial Drinking Water Quality Author: Sharpe, Taylor Jeffery Year: 2017 Waterborne disease is a significant contributor to the global burden of disease, in particular among high-risk populations in developing nations. State-of-the-art methods for the enumeration of microbial pathogens in drinking water sources have important limitations, including high initial cost, 24-48 hour delays in results, high staffing and facility requirements, and training requirements which all become especially problematic in the developing nation context. A number of alternative approaches to microbial water quality testing have been proposed, with the goal of decreasing the required testing time, decreasing overall costs, leveraging appropriate technology approaches, or improving sensitivity or specificity of the water quality testing method. One approach that may offer solutions to some of these limitations involves the deployment of sensor networks using fluorescent spectroscopy to detect intrinsic protein fluorescence in water samples as a proxy for microbial activity. In recent years, a number of researchers have found significant and meaningful correlations between indicator bacteria species and the protein fluorescence of drinking water samples. Additionally, advances in the semiconductor industry could be used to drive down the cost of such sensors. This technology may also be extensible to other water quality parameters, including dissolved organic matter or the presence of fluorescent pollutants. In this thesis, a literature review describes the fundamentals of fluorescence spectroscopy, historical and recent work regarding the fluorescence of the amino acid tryptophan and associated bacterial fluorescence, possible mechanisms for this association, and potential applications of this technology for drinking water quality monitoring and waste water process control. Extensibility of the technology is also discussed. Next, experimental methodology in reproduction of similar results is described. Samples were taken from seven (7) surface water sources and tested using membrane filtration and an off-the-shelf fluorescence spectrometer to help examine the association between the presence of indicator bacteria and the tryptophan fluorescence of the water sample. The results, showing an association of R2 = 0.560, are compared to the results of recent similar experiments. Finally, two prototypes are described, including their design requirements and data from prototype testing. The results of the testing are briefly discussed, and next steps are outlined with the goal of developing a low-cost, in-situ microbial water quality sensor using fluorescence spectroscopy principles. Close