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• 1. [Article] Relationships Between Environmental Governance and Water Quality in a Growing Metropolitan Area of the Pacific Northwest, USA

  We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro ...

  Citation × Citation Citation Abstract Copy Title: Relationships Between Environmental Governance and Water Quality in a Growing Metropolitan Area of the Pacific Northwest, USA Author: Chang, Heejun, Thiers, Paul R., Netusil, Noelwah R., Yeakley, J. Alan, Rollwagen-Bollens, Gretchen, Bollens, Steve, Singh, Sonia Year: 2014 We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro areas share many common biophysical characteristics, they have different land development histories and water governance structures, providing a unique opportunity for examining how differences in governance might affect environmental quality. We conceptualize possible linkages in which water quality influences governance directly, using monitoring efforts as a metric, and indirectly by using the change in the sale price of single-family residential properties. Governance may then influence water quality directly through riparian restoration resulting from monitoring results and indirectly through land use policy.We investigate evidence to substantiate these linkages. Our results showed that changes in monitoring regimes and land development patterns differed in response to differences in growth management policy and environmental governance systems. Our results also showed similarities in environmental quality responses to varying governance systems. For example, we found that sales prices responded positively to improved water quality (e.g., increases in DO and reductions in bacteria counts) in both cities. Furthermore, riparian restoration efforts improved over time for both cities, indicating the positive effect of governance on this land-based resource that may result in improved water quality. However, as of yet, there were no substantial differences across study areas in water temperature over time, despite an expansion of these urban areas of more than 20%over 24 years. The mechanisms by which water quality was maintained was similar in the sense that both cities benefited from riparian restoration, but different in the sense that Portland benefited indirectly from land use policy. A combination of long-term legacy effects of land development, and a relatively short history of riparian restoration in both the Portland and Vancouver regions, may have masked any subtle differences between study areas. An alternative explanation is that both cities exhibited combinations of positive indirect and direct water quality governance that resulted in maintenance of water quality in the face of increased urban growth. These findings suggest that a much longer-term water quality monitoring effort is needed to identify the effectiveness of alternative land development and water governance policies Title: Relationships Between Environmental Governance and Water Quality in a Growing Metropolitan Area of the Pacific Northwest, USA Author: Chang, Heejun, Thiers, Paul R., Netusil, Noelwah R., Yeakley, J. Alan, Rollwagen-Bollens, Gretchen, Bollens, Steve, Singh, Sonia Year: 2014 We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro areas share many common biophysical characteristics, they have different land development histories and water governance structures, providing a unique opportunity for examining how differences in governance might affect environmental quality. We conceptualize possible linkages in which water quality influences governance directly, using monitoring efforts as a metric, and indirectly by using the change in the sale price of single-family residential properties. Governance may then influence water quality directly through riparian restoration resulting from monitoring results and indirectly through land use policy.We investigate evidence to substantiate these linkages. Our results showed that changes in monitoring regimes and land development patterns differed in response to differences in growth management policy and environmental governance systems. Our results also showed similarities in environmental quality responses to varying governance systems. For example, we found that sales prices responded positively to improved water quality (e.g., increases in DO and reductions in bacteria counts) in both cities. Furthermore, riparian restoration efforts improved over time for both cities, indicating the positive effect of governance on this land-based resource that may result in improved water quality. However, as of yet, there were no substantial differences across study areas in water temperature over time, despite an expansion of these urban areas of more than 20%over 24 years. The mechanisms by which water quality was maintained was similar in the sense that both cities benefited from riparian restoration, but different in the sense that Portland benefited indirectly from land use policy. A combination of long-term legacy effects of land development, and a relatively short history of riparian restoration in both the Portland and Vancouver regions, may have masked any subtle differences between study areas. An alternative explanation is that both cities exhibited combinations of positive indirect and direct water quality governance that resulted in maintenance of water quality in the face of increased urban growth. These findings suggest that a much longer-term water quality monitoring effort is needed to identify the effectiveness of alternative land development and water governance policies Close

• 2. [Article] Development of Future Land Cover Change Scenarios in the Metropolitan Fringe, Oregon, U.S., with Stakeholder Involvement

  We describe a future land cover scenario construction process developed under consultation with a group of stakeholders from our study area. We developed a simple geographic information system (GIS) method ...

  Citation × Citation Citation Abstract Copy Title: Development of Future Land Cover Change Scenarios in the Metropolitan Fringe, Oregon, U.S., with Stakeholder Involvement Author: Chang, Heejun, Hoyer, Roberrt W. Year: 2014 We describe a future land cover scenario construction process developed under consultation with a group of stakeholders from our study area. We developed a simple geographic information system (GIS) method to modify a land cover dataset and then used qualitative data extracted from the stakeholder storyline to modify it. These identified variables related to our study area’s land use regulation system as the major driver in the placement of new urban growth on the landscape; and the accommodation of new population as the determinant of its growth rate. The outcome was a series of three scenario maps depicting a gradient of increased urbanization. The effort attempted to create a simple and transparent modeling framework that is easy to communicate. The incorporation of the regulatory context and rules and place-specific modeling for denser urban and sparse rural areas provide new insights of future land conversions. This relatively rapid mapping process provides useful information for spatial planning and projects for where and how much urban land will be present by the year 2050 Title: Development of Future Land Cover Change Scenarios in the Metropolitan Fringe, Oregon, U.S., with Stakeholder Involvement Author: Chang, Heejun, Hoyer, Roberrt W. Year: 2014 We describe a future land cover scenario construction process developed under consultation with a group of stakeholders from our study area. We developed a simple geographic information system (GIS) method to modify a land cover dataset and then used qualitative data extracted from the stakeholder storyline to modify it. These identified variables related to our study area’s land use regulation system as the major driver in the placement of new urban growth on the landscape; and the accommodation of new population as the determinant of its growth rate. The outcome was a series of three scenario maps depicting a gradient of increased urbanization. The effort attempted to create a simple and transparent modeling framework that is easy to communicate. The incorporation of the regulatory context and rules and place-specific modeling for denser urban and sparse rural areas provide new insights of future land conversions. This relatively rapid mapping process provides useful information for spatial planning and projects for where and how much urban land will be present by the year 2050 Close

• 3. [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

• 4. [Article] Land Cover, Climate, and the Summer Surface Energy Balance in Phoenix, AZ, and Portland, OR

  Changes in land use and land cover alter the local energy balance and contribute to distinct urban climates. This paper presents a local-scale above-canopy study of intra-urban land cover mixes in two ...

  Citation × Citation Citation Abstract Copy Title: Land Cover, Climate, and the Summer Surface Energy Balance in Phoenix, AZ, and Portland, OR Author: Middel, Ariane, Brazel, Anthony J., Gober, Patricia, Myint, Soe Win, Chang, Heejun, Duh, Jiunn-Der Year: 2012 Changes in land use and land cover alter the local energy balance and contribute to distinct urban climates. This paper presents a local-scale above-canopy study of intra-urban land cover mixes in two cities to analyse the relative effects of surface morphology and local climate on the surface energy balance (SEB). The study is conducted for urban areas in Phoenix, Arizona, and Portland, Oregon, cities with distinct climates but similarly warm and dry summers. A Local-Scale Urban Meteorological Parameterization Scheme (LUMPS) is used to analyse the relative contributions of local weather extremes and land cover variations on the urban energy balance. The partitioning of net all-wave radiation into turbulent sensible and latent heat fluxes as well as heat storage is investigated for a typical dry summer month and two extreme weather scenarios in the two cities. Results of sensitivity analyses show that incoming solar radiation is an important driver of the SEB in LUMPS and should be considered in the generation of climate scenarios. The relationship between individual land cover fractions and SEB fluxes is not clear because of interrelated effects of surface characteristics in the land cover mix. Daytime Bowen ratios vary inversely with vegetation fraction between and within cities for all weather scenarios. Impervious surface cover is positively correlated to the available energy that is partitioned into sensible heat. Cumulative evapotranspiration (ET) is similar for average weather conditions across medium wet sites in Phoenix and Portland but varies more in Portland than in Phoenix under extreme weather conditions. Results suggest that land cover manipulation could offset influences of weather extremes on ET in Portland to a certain degree but not in Phoenix. These findings highlight the importance of spatial and climatic context in the urban design process to mitigate the effects of urbanization. Title: Land Cover, Climate, and the Summer Surface Energy Balance in Phoenix, AZ, and Portland, OR Author: Middel, Ariane, Brazel, Anthony J., Gober, Patricia, Myint, Soe Win, Chang, Heejun, Duh, Jiunn-Der Year: 2012 Changes in land use and land cover alter the local energy balance and contribute to distinct urban climates. This paper presents a local-scale above-canopy study of intra-urban land cover mixes in two cities to analyse the relative effects of surface morphology and local climate on the surface energy balance (SEB). The study is conducted for urban areas in Phoenix, Arizona, and Portland, Oregon, cities with distinct climates but similarly warm and dry summers. A Local-Scale Urban Meteorological Parameterization Scheme (LUMPS) is used to analyse the relative contributions of local weather extremes and land cover variations on the urban energy balance. The partitioning of net all-wave radiation into turbulent sensible and latent heat fluxes as well as heat storage is investigated for a typical dry summer month and two extreme weather scenarios in the two cities. Results of sensitivity analyses show that incoming solar radiation is an important driver of the SEB in LUMPS and should be considered in the generation of climate scenarios. The relationship between individual land cover fractions and SEB fluxes is not clear because of interrelated effects of surface characteristics in the land cover mix. Daytime Bowen ratios vary inversely with vegetation fraction between and within cities for all weather scenarios. Impervious surface cover is positively correlated to the available energy that is partitioned into sensible heat. Cumulative evapotranspiration (ET) is similar for average weather conditions across medium wet sites in Phoenix and Portland but varies more in Portland than in Phoenix under extreme weather conditions. Results suggest that land cover manipulation could offset influences of weather extremes on ET in Portland to a certain degree but not in Phoenix. These findings highlight the importance of spatial and climatic context in the urban design process to mitigate the effects of urbanization. Close

• 5. [Article] Stressors and Strategies for Managing Urban Water Scarcity: Perspectives from the Field

  Largely because water resource planning in the U.S. has been separated from land-use planning, opportunities for explicitly linking planning policies to water availability remain unexamined. The pressing ...

  Citation × Citation Citation Abstract Copy Title: Stressors and Strategies for Managing Urban Water Scarcity: Perspectives from the Field Author: Shandas, Vivek, Lehman, Rosa, Larson, Kelli L., Bunn, Jeremy, Chang, Heejun Year: 2015 Largely because water resource planning in the U.S. has been separated from land-use planning, opportunities for explicitly linking planning policies to water availability remain unexamined. The pressing need for better coordination between land-use planning and water management is amplified by changes in the global climate, which will place even greater importance on managing water supplies and demands than in the past. By surveying land and water managers in two urbanizing regions of the western United States—Portland, Oregon and Phoenix Arizona—we assessed the extent to which their perspectives regarding municipal water resource management align or differ. We specifically focus on characterizing how they perceive water scarcity problems (i.e., stressors) and solutions (i.e., strategies). Overall, the results show a general agreement across both regions and professions that long-term drought, population growth, and outdoor water use are the most important stressors to urban water systems. The results of the survey indicated more agreement across cities than across professions with regard to effective strategies, reinforcing the idea that land-use planners and water managers remain divided in their conception of the solutions to urban water management. To conclude, we recommend potential pathways for coordinating the fields of land and water management for urban sustainability. Title: Stressors and Strategies for Managing Urban Water Scarcity: Perspectives from the Field Author: Shandas, Vivek, Lehman, Rosa, Larson, Kelli L., Bunn, Jeremy, Chang, Heejun Year: 2015 Largely because water resource planning in the U.S. has been separated from land-use planning, opportunities for explicitly linking planning policies to water availability remain unexamined. The pressing need for better coordination between land-use planning and water management is amplified by changes in the global climate, which will place even greater importance on managing water supplies and demands than in the past. By surveying land and water managers in two urbanizing regions of the western United States—Portland, Oregon and Phoenix Arizona—we assessed the extent to which their perspectives regarding municipal water resource management align or differ. We specifically focus on characterizing how they perceive water scarcity problems (i.e., stressors) and solutions (i.e., strategies). Overall, the results show a general agreement across both regions and professions that long-term drought, population growth, and outdoor water use are the most important stressors to urban water systems. The results of the survey indicated more agreement across cities than across professions with regard to effective strategies, reinforcing the idea that land-use planners and water managers remain divided in their conception of the solutions to urban water management. To conclude, we recommend potential pathways for coordinating the fields of land and water management for urban sustainability. Close

• 6. [Article] Using Spatially Explicit Indicators to Investigate Watershed Characteristics and stream temperature relationships

  We generate a series of novel indicators of spatially explicit watershed permeability and runoff characteristics to examine the relationship between land cover and water temperature parameters in a rapidly ...

  Citation × Citation Citation Abstract Copy Title: Using Spatially Explicit Indicators to Investigate Watershed Characteristics and stream temperature relationships Author: Grabowski, Zbigniew J., Watson, Eric, Chang, Heejun Year: 2016 We generate a series of novel indicators of spatially explicit watershed permeability and runoff characteristics to examine the relationship between land cover and water temperature parameters in a rapidly urbanizing watershed. Our framework provides a readily adaptable method to examine the thermal sensitivity of streams based upon the underlying geomorphological and surface characteristics of drainage basins. Using four model groups each using a different landscape characteristic weighting scheme (Model Group 1: areal averages; Model Group 2: inverse distance by total flow length; Model Group 3: overland distance to stream network and distance squared; Model Group 4: proportional flow accumulation), we examined the predictive capacity of 19 variables, including combinations of simplified land cover, elevation, slope, and flow accumulation, on five stream thermal properties: seven day moving average of daily minimum and maximum, seasonal mean temperature, a novel metric of thermal 'flashiness', and total days with maximum temperature exceeding 17.8°C. We find that the use of spatially explicit landscape indicators combining watershed processes improves the performance of regressions for predicting a number of ecologically relevant stream temperature variables. Improved indicators of watershed condition lend themselves for rapid investigation of the relationship between stream thermal conditions and landscape characteristics in watersheds modified by human land uses, ultimately providing a more hydrologically meaningful indicator for the impacts of landscape change. Title: Using Spatially Explicit Indicators to Investigate Watershed Characteristics and stream temperature relationships Author: Grabowski, Zbigniew J., Watson, Eric, Chang, Heejun Year: 2016 We generate a series of novel indicators of spatially explicit watershed permeability and runoff characteristics to examine the relationship between land cover and water temperature parameters in a rapidly urbanizing watershed. Our framework provides a readily adaptable method to examine the thermal sensitivity of streams based upon the underlying geomorphological and surface characteristics of drainage basins. Using four model groups each using a different landscape characteristic weighting scheme (Model Group 1: areal averages; Model Group 2: inverse distance by total flow length; Model Group 3: overland distance to stream network and distance squared; Model Group 4: proportional flow accumulation), we examined the predictive capacity of 19 variables, including combinations of simplified land cover, elevation, slope, and flow accumulation, on five stream thermal properties: seven day moving average of daily minimum and maximum, seasonal mean temperature, a novel metric of thermal 'flashiness', and total days with maximum temperature exceeding 17.8°C. We find that the use of spatially explicit landscape indicators combining watershed processes improves the performance of regressions for predicting a number of ecologically relevant stream temperature variables. Improved indicators of watershed condition lend themselves for rapid investigation of the relationship between stream thermal conditions and landscape characteristics in watersheds modified by human land uses, ultimately providing a more hydrologically meaningful indicator for the impacts of landscape change. Close

• 7. [Article] Spatial and Temporal Patterns in the Influence of Land Use on Water Quality in Five Portland Area Creeks Representing Differing Levels of Urbanization

  While the negative effects of urban development on freshwater systems are well documented, impacts of human disturbance on water quality vary depending on land cover, local climate, and temporal and spatial ...

  Citation × Citation Citation Abstract Copy Title: Spatial and Temporal Patterns in the Influence of Land Use on Water Quality in Five Portland Area Creeks Representing Differing Levels of Urbanization Author: Chang, Heejun, Steele, Madeline, Bonak, Zoe Year: 2011 While the negative effects of urban development on freshwater systems are well documented, impacts of human disturbance on water quality vary depending on land cover, local climate, and temporal and spatial scales of analysis. To better understand this variation, we analyzed water quality data for a total of 15 sites from six Portland, Oregon area creeks at multiple spatial and temporal scales. The creeks are characterized by differing levels of urban development, from relatively pristine to highly developed. More than ten years of monthly data gathered by the Portland Bureau of Environmental Services were used to analyze temporal trends, and five years of these data were used to analyze spatial patterns. Analytes of interest were specific conductivity, dissolved oxygen, nitrate, phosphorus, total suspended solids, and temperature. These variables were compared to contributing area land use metrics at three scales: full contributing sub-basin, 100-meter riparian corridor, and 50-meter riparian corridor. We calculated seven land use metrics: population density, street density, Green Streets density, percent low density development, percent high density development, percent forested area, and percent agriculture. We found Spearman?s Rank Correlation Coefficient between the water quality parameters for annual, wet, and dry seasons and the land use metrics at each spatial scale for each parameter. The same water quality data were also analyzed for correlations to same day as well as 3-, 5-, and 7-day antecedent precipitation to examine relationships between water quality and environmental moisture conditions. Additionally, we used a Seasonal Kendall test to search for temporal trends. For each site included in the temporal analysis, changes in population density and street density metrics from 2000 to 2010 were compared to changes in water quality. Results vary across space, but generally confirm that urban development has negatively impacted the creeks. Specific conductivity, total suspended solids and nitrate are particularly sensitive to the level of urban development, especially following rain events. This work will help to better understand and mitigate urbanization impacts on freshwater systems. Title: Spatial and Temporal Patterns in the Influence of Land Use on Water Quality in Five Portland Area Creeks Representing Differing Levels of Urbanization Author: Chang, Heejun, Steele, Madeline, Bonak, Zoe Year: 2011 While the negative effects of urban development on freshwater systems are well documented, impacts of human disturbance on water quality vary depending on land cover, local climate, and temporal and spatial scales of analysis. To better understand this variation, we analyzed water quality data for a total of 15 sites from six Portland, Oregon area creeks at multiple spatial and temporal scales. The creeks are characterized by differing levels of urban development, from relatively pristine to highly developed. More than ten years of monthly data gathered by the Portland Bureau of Environmental Services were used to analyze temporal trends, and five years of these data were used to analyze spatial patterns. Analytes of interest were specific conductivity, dissolved oxygen, nitrate, phosphorus, total suspended solids, and temperature. These variables were compared to contributing area land use metrics at three scales: full contributing sub-basin, 100-meter riparian corridor, and 50-meter riparian corridor. We calculated seven land use metrics: population density, street density, Green Streets density, percent low density development, percent high density development, percent forested area, and percent agriculture. We found Spearman?s Rank Correlation Coefficient between the water quality parameters for annual, wet, and dry seasons and the land use metrics at each spatial scale for each parameter. The same water quality data were also analyzed for correlations to same day as well as 3-, 5-, and 7-day antecedent precipitation to examine relationships between water quality and environmental moisture conditions. Additionally, we used a Seasonal Kendall test to search for temporal trends. For each site included in the temporal analysis, changes in population density and street density metrics from 2000 to 2010 were compared to changes in water quality. Results vary across space, but generally confirm that urban development has negatively impacted the creeks. Specific conductivity, total suspended solids and nitrate are particularly sensitive to the level of urban development, especially following rain events. This work will help to better understand and mitigate urbanization impacts on freshwater systems. Close

• 8. [Article] Determinants of Single Family Residential Water Use Across Scales in Four Western US Cities

  A growing body of literature examines urban water sustainability with increasing evidence that locally-based physical and social spatial interactions contribute to water use. These studies however are ...

  Citation × Citation Citation Abstract Copy Title: Determinants of Single Family Residential Water Use Across Scales in Four Western US Cities Author: Chang, Heejun, Bonnette, Matthew Ryan, Stoker, Philip, Crow-Miller, Britt, Wentz, Elizabeth A, Year: 2017 A growing body of literature examines urban water sustainability with increasing evidence that locally-based physical and social spatial interactions contribute to water use. These studies however are based on single-city analysis and often fail to consider whether these interactions occur more generally. We examine a multi-city comparison using a common set of spatially-explicit water, socioeconomic, and biophysical data. We investigate the relative importance of variables for explaining the variations of single family residential (SFR) water uses at Census Block Group (CBG) and Census Tract (CT) scales in four representative western US cities - Austin, Phoenix, Portland, and Salt Lake City, - which cover a wide range of climate and development density. We used both ordinary least squares regression and spatial error regression models to identify the influence of spatial dependence on water use patterns. Our results show that older downtown areas show lower water use than newer suburban areas in all four cities. Tax assessed value and building age are the main determinants of SFR water use across the four cities regardless of the scale. Impervious surface area becomes an important variable for summer water use in all cities, and it is important in all seasons for arid environments such as Phoenix. CT level analysis shows better model predictability than CBG analysis. In all cities, seasons, and spatial scales, spatial error regression models better explain the variations of SFR water use. Such a spatially-varying relationship of urban water consumption provides additional evidence for the need to integrate urban land use planning and municipal water planning. (C) 2017 Elsevier B.V. All rights reserved. Title: Determinants of Single Family Residential Water Use Across Scales in Four Western US Cities Author: Chang, Heejun, Bonnette, Matthew Ryan, Stoker, Philip, Crow-Miller, Britt, Wentz, Elizabeth A, Year: 2017 A growing body of literature examines urban water sustainability with increasing evidence that locally-based physical and social spatial interactions contribute to water use. These studies however are based on single-city analysis and often fail to consider whether these interactions occur more generally. We examine a multi-city comparison using a common set of spatially-explicit water, socioeconomic, and biophysical data. We investigate the relative importance of variables for explaining the variations of single family residential (SFR) water uses at Census Block Group (CBG) and Census Tract (CT) scales in four representative western US cities - Austin, Phoenix, Portland, and Salt Lake City, - which cover a wide range of climate and development density. We used both ordinary least squares regression and spatial error regression models to identify the influence of spatial dependence on water use patterns. Our results show that older downtown areas show lower water use than newer suburban areas in all four cities. Tax assessed value and building age are the main determinants of SFR water use across the four cities regardless of the scale. Impervious surface area becomes an important variable for summer water use in all cities, and it is important in all seasons for arid environments such as Phoenix. CT level analysis shows better model predictability than CBG analysis. In all cities, seasons, and spatial scales, spatial error regression models better explain the variations of SFR water use. Such a spatially-varying relationship of urban water consumption provides additional evidence for the need to integrate urban land use planning and municipal water planning. (C) 2017 Elsevier B.V. All rights reserved. Close

• 9. [Article] A Geospatial Tool for Wetland Prioritization at the Watershed Scale

  There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential ...

  Citation × Citation Citation Abstract Copy Title: A Geospatial Tool for Wetland Prioritization at the Watershed Scale Author: Blackmore, Debra Sue, Chang, Heejun Year: 2015 There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential of selected ecosystem functions for freshwater wetlands within a watershed using widely available geospatial data. We developed four functions to estimate 1) flood storage, 2) late season flow, 3) sediment retention and 4) temperature control in four pilot watersheds in Oregon (Tualatin, Coquille, Upper Grande Ronde and Sprague). These watersheds are geographically separated from each other representing diverse ecoregion environments. Spatial analysis and geographic information system (GIS) were designed for maximum re-use, based on publicly-available data, commonly-used software, semi-automated techniques and wetland characterizations that attempt to capture fundamental wetland processes. Our data sources include 30-meter digital elevation models, NRCS soil survey extracts, USGS National Land Cover Data, USGS HUC8 boundaries (polygons) and statewide wetland delineations (polygons) processed within ArcGIS 10.2 and Python 2.7.5 software. Model parameters were compiled using multiple proxy values for size, slope, aspect, proximity, flow path distance, hydrologic gradient, shade, and soil characteristics. WPT characterizations emphasize the multi-faceted value of freshwater wetlands, relating potential within a watershed as well as providing model-based characterizations between watersheds. Our wetland prioritization tool (WPT) provides useful information to estimate and compare the relative potential for selected wetland functions, thereby improving success in wetland conservation, restoration, and mitigation efforts. Title: A Geospatial Tool for Wetland Prioritization at the Watershed Scale Author: Blackmore, Debra Sue, Chang, Heejun Year: 2015 There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential of selected ecosystem functions for freshwater wetlands within a watershed using widely available geospatial data. We developed four functions to estimate 1) flood storage, 2) late season flow, 3) sediment retention and 4) temperature control in four pilot watersheds in Oregon (Tualatin, Coquille, Upper Grande Ronde and Sprague). These watersheds are geographically separated from each other representing diverse ecoregion environments. Spatial analysis and geographic information system (GIS) were designed for maximum re-use, based on publicly-available data, commonly-used software, semi-automated techniques and wetland characterizations that attempt to capture fundamental wetland processes. Our data sources include 30-meter digital elevation models, NRCS soil survey extracts, USGS National Land Cover Data, USGS HUC8 boundaries (polygons) and statewide wetland delineations (polygons) processed within ArcGIS 10.2 and Python 2.7.5 software. Model parameters were compiled using multiple proxy values for size, slope, aspect, proximity, flow path distance, hydrologic gradient, shade, and soil characteristics. WPT characterizations emphasize the multi-faceted value of freshwater wetlands, relating potential within a watershed as well as providing model-based characterizations between watersheds. Our wetland prioritization tool (WPT) provides useful information to estimate and compare the relative potential for selected wetland functions, thereby improving success in wetland conservation, restoration, and mitigation efforts. Close

• 10. [Article] Facilitating Collaborative Urban Water Management Through University-Utility Cooperation

  In the face of intensifying stresses such as climate change, rapid urban population growth, land use change, and public concern with rates and use restrictions, water management is becoming increasingly ...

  Citation × Citation Citation Abstract Copy Title: Facilitating Collaborative Urban Water Management Through University-Utility Cooperation Author: Crow-Miller, Britt, Chang, Heejun, Stoker, Philip, Wentz, Elizabeth A, Year: 2016 In the face of intensifying stresses such as climate change, rapid urban population growth, land use change, and public concern with rates and use restrictions, water management is becoming increasingly complex in the cities of the American West. One strategy to improve water management practices in this changing social-ecological context is to develop collaborative relationships that facilitate the engagement of multiple stakeholders at multiple scales. At the local level, one important but frequently underdeveloped collaborative link is that between university researchers and water utilities, who together occupy the interstitial space between science and decision-making, while at the same time interfacing with water users. Based on workshop data, a pilot survey, and interviews with representative water managers and university researchers from cities across the American West, we identify a number of barriers to establishing collaborative platforms from which utilities and university researchers can effectively work together to tackle challenges around sustainable urban water management in the twenty-first century. We make suggestions for overcoming these barriers and argue that developing an integrated model for university-utility collaborations is a critical area on which we must focus our collective attention if sustainable urban water management is to be achieved. Title: Facilitating Collaborative Urban Water Management Through University-Utility Cooperation Author: Crow-Miller, Britt, Chang, Heejun, Stoker, Philip, Wentz, Elizabeth A, Year: 2016 In the face of intensifying stresses such as climate change, rapid urban population growth, land use change, and public concern with rates and use restrictions, water management is becoming increasingly complex in the cities of the American West. One strategy to improve water management practices in this changing social-ecological context is to develop collaborative relationships that facilitate the engagement of multiple stakeholders at multiple scales. At the local level, one important but frequently underdeveloped collaborative link is that between university researchers and water utilities, who together occupy the interstitial space between science and decision-making, while at the same time interfacing with water users. Based on workshop data, a pilot survey, and interviews with representative water managers and university researchers from cities across the American West, we identify a number of barriers to establishing collaborative platforms from which utilities and university researchers can effectively work together to tackle challenges around sustainable urban water management in the twenty-first century. We make suggestions for overcoming these barriers and argue that developing an integrated model for university-utility collaborations is a critical area on which we must focus our collective attention if sustainable urban water management is to be achieved. Close