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• 1. [Article] Assessing the Potential of Land Use Modification to Mitigate Ambient NO2 and Its Consequences for Respiratory Health

  Understanding how local land use and land cover (LULC) shapes intra-urban concentrations of atmospheric pollutants—and thus human health—is a key component in designing healthier cities. Here, NO2 is modeled ...

  Citation × Citation Citation Abstract Copy Title: Assessing the Potential of Land Use Modification to Mitigate Ambient NO2 and Its Consequences for Respiratory Health Author: Rao, Meenakshi, George, Linda A., Shandas, Vivek, Rosenstiel, Todd N. Year: 2017 Understanding how local land use and land cover (LULC) shapes intra-urban concentrations of atmospheric pollutants—and thus human health—is a key component in designing healthier cities. Here, NO2 is modeled based on spatially dense summer and winter NO2 observations in Portland-Hillsboro-Vancouver (USA), and the spatial variation of NO2 with LULC investigated using random forest, an ensemble data learning technique. The NO2 random forest model, together with BenMAP, is further used to develop a better understanding of the relationship among LULC, ambient NO2 and respiratory health. The impact of land use modifications on ambient NO2, and consequently on respiratory health, is also investigated using a sensitivity analysis. We find that NO2 associated with roadways and tree-canopied areas may be affecting annual incidence rates of asthma exacerbation in 4–12 year olds by +3000 per 100,000 and -1400 per 100,000, respectively. Our model shows that increasing local tree canopy by 5% may reduce local incidences rates of asthma exacerbation by 6%, indicating that targeted local tree-planting efforts may have a substantial impact on reducing city-wide incidence of respiratory distress. Our findings demonstrate the utility of random forest modeling in evaluating LULC modifications for enhanced respiratory health. Title: Assessing the Potential of Land Use Modification to Mitigate Ambient NO2 and Its Consequences for Respiratory Health Author: Rao, Meenakshi, George, Linda A., Shandas, Vivek, Rosenstiel, Todd N. Year: 2017 Understanding how local land use and land cover (LULC) shapes intra-urban concentrations of atmospheric pollutants—and thus human health—is a key component in designing healthier cities. Here, NO2 is modeled based on spatially dense summer and winter NO2 observations in Portland-Hillsboro-Vancouver (USA), and the spatial variation of NO2 with LULC investigated using random forest, an ensemble data learning technique. The NO2 random forest model, together with BenMAP, is further used to develop a better understanding of the relationship among LULC, ambient NO2 and respiratory health. The impact of land use modifications on ambient NO2, and consequently on respiratory health, is also investigated using a sensitivity analysis. We find that NO2 associated with roadways and tree-canopied areas may be affecting annual incidence rates of asthma exacerbation in 4–12 year olds by +3000 per 100,000 and -1400 per 100,000, respectively. Our model shows that increasing local tree canopy by 5% may reduce local incidences rates of asthma exacerbation by 6%, indicating that targeted local tree-planting efforts may have a substantial impact on reducing city-wide incidence of respiratory distress. Our findings demonstrate the utility of random forest modeling in evaluating LULC modifications for enhanced respiratory health. Close

• 2. [Article] Issues in Trip Generation Methods for Transportation Impact Estimation of Land Use Development: A Review and Discussion of the State-of-the-Art Approaches

  As agencies develop more robust planning objectives for creating sustainable and livable communities, the research community has continued developing supportive tools and methods to provide more accurate ...

  Citation × Citation Citation Abstract Copy Title: Issues in Trip Generation Methods for Transportation Impact Estimation of Land Use Development: A Review and Discussion of the State-of-the-Art Approaches Author: Currans, Kristina Marie Year: 2017 As agencies develop more robust planning objectives for creating sustainable and livable communities, the research community has continued developing supportive tools and methods to provide more accurate and robust means for estimating transportation impacts for site-level development review. This paper is a review of the state-of-the-art trip generation methods for land use transportation impact estimation. First, it provides an overview of the more recent available and peer-reviewed estimation methods. Second, the authors offer a discussion of the successes of state-of-the-art approaches using common themes of research to identify corresponding consistency with theories of travel behavior and urban economics. These themes include: (a) the ability to estimate overall amounts of activity; (b) built environment and multimodal estimation; (c) socio-and economic demographics; (d) mixed and/or multiuse methods; and (e) land use (dis)aggregation. The main objective of this paper is to, throughout the discussion and conclusions, identify the largest and potentially problematic gaps in the state-of-the-art methods available for practice in order to allow researchers, agencies, and practitioners to both be aware of these limitations and forge forward new innovations to solve these on-going problems Title: Issues in Trip Generation Methods for Transportation Impact Estimation of Land Use Development: A Review and Discussion of the State-of-the-Art Approaches Author: Currans, Kristina Marie Year: 2017 As agencies develop more robust planning objectives for creating sustainable and livable communities, the research community has continued developing supportive tools and methods to provide more accurate and robust means for estimating transportation impacts for site-level development review. This paper is a review of the state-of-the-art trip generation methods for land use transportation impact estimation. First, it provides an overview of the more recent available and peer-reviewed estimation methods. Second, the authors offer a discussion of the successes of state-of-the-art approaches using common themes of research to identify corresponding consistency with theories of travel behavior and urban economics. These themes include: (a) the ability to estimate overall amounts of activity; (b) built environment and multimodal estimation; (c) socio-and economic demographics; (d) mixed and/or multiuse methods; and (e) land use (dis)aggregation. The main objective of this paper is to, throughout the discussion and conclusions, identify the largest and potentially problematic gaps in the state-of-the-art methods available for practice in order to allow researchers, agencies, and practitioners to both be aware of these limitations and forge forward new innovations to solve these on-going problems Close

• 3. [Article] Accessibility, Income, and Person Trip Generation: Multilevel Model of Activity at Food Retail Establishments in Portland, Oregon

  In the past decade, the methods for estimating multimodal transportation impacts of urban land use development have improved substantially. One assumption commonly made in these new methods is that overall ...

  Citation × Citation Citation Abstract Copy Title: Accessibility, Income, and Person Trip Generation: Multilevel Model of Activity at Food Retail Establishments in Portland, Oregon Author: Currans, Kristina Marie, Clifton, Kelly Year: 2017 In the past decade, the methods for estimating multimodal transportation impacts of urban land use development have improved substantially. One assumption commonly made in these new methods is that overall person-trip rates at similarly-sized establishments of the same land use do not vary across a region. This is an assumption of convenience to permit the adjustment of ITE Trip Generation vehicle trip rates for use in different urban environments. However, this assumption is inconsistent with theories of urban economics, which recognize that businesses pay a premium to locate in areas with high levels of accessibility to attract more customers. In addition, most transportation impact analyses have ignored income effects, even though socio-economics are a proven driver of travel behavior. To test this assumption and understand the effects of accessibility and income on levels of activity at the establishment level, we examine transaction counts for 97 grocery and convenience markets in Portland, Oregon. In a multilevel negative binomial regression, we test the relationship of regional accessibility, local accessibility, and income on weekly and daily transaction rates. While there was not enough evidence to suggest a significant relationship between accessibility and transaction rates, the results indicated a significant relationship with median income of the surrounding area. The implications point to the need to consider area-wide socio-demographics in site-level transportation impact analysis. The study also provides some important discussion about the use of transaction as a proxy for person-trip rates. Title: Accessibility, Income, and Person Trip Generation: Multilevel Model of Activity at Food Retail Establishments in Portland, Oregon Author: Currans, Kristina Marie, Clifton, Kelly Year: 2017 In the past decade, the methods for estimating multimodal transportation impacts of urban land use development have improved substantially. One assumption commonly made in these new methods is that overall person-trip rates at similarly-sized establishments of the same land use do not vary across a region. This is an assumption of convenience to permit the adjustment of ITE Trip Generation vehicle trip rates for use in different urban environments. However, this assumption is inconsistent with theories of urban economics, which recognize that businesses pay a premium to locate in areas with high levels of accessibility to attract more customers. In addition, most transportation impact analyses have ignored income effects, even though socio-economics are a proven driver of travel behavior. To test this assumption and understand the effects of accessibility and income on levels of activity at the establishment level, we examine transaction counts for 97 grocery and convenience markets in Portland, Oregon. In a multilevel negative binomial regression, we test the relationship of regional accessibility, local accessibility, and income on weekly and daily transaction rates. While there was not enough evidence to suggest a significant relationship between accessibility and transaction rates, the results indicated a significant relationship with median income of the surrounding area. The implications point to the need to consider area-wide socio-demographics in site-level transportation impact analysis. The study also provides some important discussion about the use of transaction as a proxy for person-trip rates. Close

• 4. [Article] Continuous Data Integration for Land Use and Transportation Planning and Modeling

  There is an urgent need for improved models that address the interdependencies between land use and transportation, and considerable new work is underway to develop such models in Oregon and elsewhere. ...

  Citation × Citation Citation Abstract Copy Title: Continuous Data Integration for Land Use and Transportation Planning and Modeling Author: Wang, Liming, Kim, Kihong Year: 2014 There is an urgent need for improved models that address the interdependencies between land use and transportation, and considerable new work is underway to develop such models in Oregon and elsewhere. These models and planning practices to integrate land use into the process, however, require the integration of massive amounts of land use data that is messy and incomplete. There have been considerable advances in the treatment of such data problems in other domains, drawing on data mining and machine-learning techniques to address issues in various domains. To date, however, little systematic effort has applied these technological advances to the problem domain of land use and transportation data. Experience suggests that as much as 70% of the total effort in developing integrated land use and transportation models is directly or indirectly associated with data development, integration and cleaning, yet there is remarkably little systematic research focused on the development of reusable methods and tools to support this problem domain. In coordination with an ongoing project of similar theme funded by University of California Transportation Center (UCTC), this project will focus on bringing interdisciplinary methods to develop land use datasets for integrated land use and transportation planning and modeling, with special attention on preserving temporal dimension of the data and monitoring data quality through indicators. Utilizing statistics and machine-learning techniques, we will develop reusable tools that will create a harmonized and coherent land use database from various public and private sources. These tools will be made available to the public and can be used by cities, counties, metropolitan planning agencies, state agencies, universities or anyone else needing to develop a usable database for use in integrated planning and modeling. All of the resulting data, with the exception of proprietary or confidential input data where there is no viable alternative, would be public and reusable for planning and research. Title: Continuous Data Integration for Land Use and Transportation Planning and Modeling Author: Wang, Liming, Kim, Kihong Year: 2014 There is an urgent need for improved models that address the interdependencies between land use and transportation, and considerable new work is underway to develop such models in Oregon and elsewhere. These models and planning practices to integrate land use into the process, however, require the integration of massive amounts of land use data that is messy and incomplete. There have been considerable advances in the treatment of such data problems in other domains, drawing on data mining and machine-learning techniques to address issues in various domains. To date, however, little systematic effort has applied these technological advances to the problem domain of land use and transportation data. Experience suggests that as much as 70% of the total effort in developing integrated land use and transportation models is directly or indirectly associated with data development, integration and cleaning, yet there is remarkably little systematic research focused on the development of reusable methods and tools to support this problem domain. In coordination with an ongoing project of similar theme funded by University of California Transportation Center (UCTC), this project will focus on bringing interdisciplinary methods to develop land use datasets for integrated land use and transportation planning and modeling, with special attention on preserving temporal dimension of the data and monitoring data quality through indicators. Utilizing statistics and machine-learning techniques, we will develop reusable tools that will create a harmonized and coherent land use database from various public and private sources. These tools will be made available to the public and can be used by cities, counties, metropolitan planning agencies, state agencies, universities or anyone else needing to develop a usable database for use in integrated planning and modeling. All of the resulting data, with the exception of proprietary or confidential input data where there is no viable alternative, would be public and reusable for planning and research. Close

• 5. [Article] Seeking Solutions to Long-Term Public Engagement in Rapidly Diversifying Communities: A Case Study in Washington County, Oregon

  This paper explores the challenges in engaging a rapidly diversifying public in county government decision-making. The State of Oregon recognized the importance of meaningful public engagement by naming ...

  Citation × Citation Citation Abstract Copy Title: Seeking Solutions to Long-Term Public Engagement in Rapidly Diversifying Communities: A Case Study in Washington County, Oregon Author: Merrick, Meg, Tremoulet, Andrée Year: 2016 This paper explores the challenges in engaging a rapidly diversifying public in county government decision-making. The State of Oregon recognized the importance of meaningful public engagement by naming it as the first goal of its landmark statewide land use planning system adopted in 1973. Washington County, which is part of Portland’s tri-county metropolitan region, is geographically large, historically white but, in recent years, rapidly diversifying. It is also largely suburban and includes the region’s largest unincorporated communities. In addition, Washington County includes significant agricultural activities and small rural communities. Title: Seeking Solutions to Long-Term Public Engagement in Rapidly Diversifying Communities: A Case Study in Washington County, Oregon Author: Merrick, Meg, Tremoulet, Andrée Year: 2016 This paper explores the challenges in engaging a rapidly diversifying public in county government decision-making. The State of Oregon recognized the importance of meaningful public engagement by naming it as the first goal of its landmark statewide land use planning system adopted in 1973. Washington County, which is part of Portland’s tri-county metropolitan region, is geographically large, historically white but, in recent years, rapidly diversifying. It is also largely suburban and includes the region’s largest unincorporated communities. In addition, Washington County includes significant agricultural activities and small rural communities. Close

• 6. [Article] Looking Back at Planning Oregon

  An interview with Henry Richmond is the product of a new project called People and the Land: An Oral History of Oregon's Statewide Land Use Planning Program. Richmond explains the political and economic ...

  Citation × Citation Citation Abstract Copy Title: Looking Back at Planning Oregon Author: Richmond, Henry, Sitzman, James Year: 2016 An interview with Henry Richmond is the product of a new project called People and the Land: An Oral History of Oregon's Statewide Land Use Planning Program. Richmond explains the political and economic conditions in which land use program was forged, and how these have changed over time. The full interview is available here: http://archives.pdx.edu/ds/psu/16296 Title: Looking Back at Planning Oregon Author: Richmond, Henry, Sitzman, James Year: 2016 An interview with Henry Richmond is the product of a new project called People and the Land: An Oral History of Oregon's Statewide Land Use Planning Program. Richmond explains the political and economic conditions in which land use program was forged, and how these have changed over time. The full interview is available here: http://archives.pdx.edu/ds/psu/16296 Close

• 7. [Article] Travel Mode Choice Framework Incorporating Realistic Bike and Walk Routes

  For a number of reasons--congestion, public health, greenhouse gas emissions, energy use, demographic shifts, and community livability to name a few--the importance of walking and bicycling as transportation ...

  Citation × Citation Citation Abstract Copy Title: Travel Mode Choice Framework Incorporating Realistic Bike and Walk Routes Author: Broach, Joseph Paul Year: 2016 For a number of reasons--congestion, public health, greenhouse gas emissions, energy use, demographic shifts, and community livability to name a few--the importance of walking and bicycling as transportation options will only continue to increase. Currently, policy interest and infrastructure funding for nonmotorized modes far outstrip our ability to model bike and walk travel. To ensure scarce resources are used most effectively, accurate models sensitive to key policy variables are needed to support long-range planning and project evaluation, and to continue adding to our growing understanding of key factors driving walk and bike behavior. This research attempts to synthesize and advance the state of the art in trip-based, nonmotorized mode choice modeling. Over the past fifteen years, efforts to model the decision to walk or bike on a given trip have been hampered by the lack of a comprehensive behavioral framework and inconsistency in measurement scales and model specification. This project develops a mode choice behavioral framework that acknowledges the importance of attributes along the specific walk and bike routes that travelers are likely to consider, in addition to more traditional area-based measures of travel environments. The proposed framework is applied to a revealed preference, GPS-based travel dataset collected from 2010-2013 in Portland, Oregon. Measurement of nonmotorized trip distance, built environment, tour-level variables, and attitudinal attributes as well as mode availability are explicitly addressed. Route and mode choice models are specified using discrete choice techniques, and predicted walking and bicycling routes are tested as inputs to various mode choice models. Results suggest strong potential for predicted route measures to enhance walk and bicycle mode choice modeling. Findings also support the specific notion that bicycle and pedestrian infrastructure contribute not only to route choice but also to the choice of whether to bike or walk. For decisions to bicycle, availability of low-traffic routes may be particularly important to women. Model results further indicate that land use and built environments around trip ends and a person’s home still have important effects on nonmotorized travel when controlling for route quality. Both route and area travel environment impacts are mostly robust to the inclusion of residential self-selection variables, consistent with the idea that built environment differences matter even for households that choose to live in a walkable or bikeable neighborhood. The combination of area and route-based built environment measures alongside trip context, sociodemographic, and attitudinal attributes provides a new perspective on nonmotorized travel behavior relevant to both policy and practice. Title: Travel Mode Choice Framework Incorporating Realistic Bike and Walk Routes Author: Broach, Joseph Paul Year: 2016 For a number of reasons--congestion, public health, greenhouse gas emissions, energy use, demographic shifts, and community livability to name a few--the importance of walking and bicycling as transportation options will only continue to increase. Currently, policy interest and infrastructure funding for nonmotorized modes far outstrip our ability to model bike and walk travel. To ensure scarce resources are used most effectively, accurate models sensitive to key policy variables are needed to support long-range planning and project evaluation, and to continue adding to our growing understanding of key factors driving walk and bike behavior. This research attempts to synthesize and advance the state of the art in trip-based, nonmotorized mode choice modeling. Over the past fifteen years, efforts to model the decision to walk or bike on a given trip have been hampered by the lack of a comprehensive behavioral framework and inconsistency in measurement scales and model specification. This project develops a mode choice behavioral framework that acknowledges the importance of attributes along the specific walk and bike routes that travelers are likely to consider, in addition to more traditional area-based measures of travel environments. The proposed framework is applied to a revealed preference, GPS-based travel dataset collected from 2010-2013 in Portland, Oregon. Measurement of nonmotorized trip distance, built environment, tour-level variables, and attitudinal attributes as well as mode availability are explicitly addressed. Route and mode choice models are specified using discrete choice techniques, and predicted walking and bicycling routes are tested as inputs to various mode choice models. Results suggest strong potential for predicted route measures to enhance walk and bicycle mode choice modeling. Findings also support the specific notion that bicycle and pedestrian infrastructure contribute not only to route choice but also to the choice of whether to bike or walk. For decisions to bicycle, availability of low-traffic routes may be particularly important to women. Model results further indicate that land use and built environments around trip ends and a person’s home still have important effects on nonmotorized travel when controlling for route quality. Both route and area travel environment impacts are mostly robust to the inclusion of residential self-selection variables, consistent with the idea that built environment differences matter even for households that choose to live in a walkable or bikeable neighborhood. The combination of area and route-based built environment measures alongside trip context, sociodemographic, and attitudinal attributes provides a new perspective on nonmotorized travel behavior relevant to both policy and practice. Close

• 8. [Article] The Value of Place: Planning for Walkability in the Tigard Triangle

  The “Tigard Triangle” is bounded by highways and characterized by auto-oriented land uses in an incomplete street grid. It currently presents a challenge to the City of Tigard, whose vision is to be the ...

  Citation × Citation Citation Abstract Copy Title: The Value of Place: Planning for Walkability in the Tigard Triangle Author: Abuhejleh, Wala, Atkinson, Ray, Davis, Linn, Fisher, Curtis Year: 2016 The “Tigard Triangle” is bounded by highways and characterized by auto-oriented land uses in an incomplete street grid. It currently presents a challenge to the City of Tigard, whose vision is to be the most walkable community in the Pacific Northwest. The purpose of the Value of Place project is to develop a plan for improving walkability, safety, comfort, and aesthetics in the Tigard Triangle. In addition, this project was developed to test the application of the State of Place analytical tools to the planning and design challenges faced by the city. This project was conducted under the supervision of Ethan Seltzer, Marisa Zapata, and Susan Hartnett. Title: The Value of Place: Planning for Walkability in the Tigard Triangle Author: Abuhejleh, Wala, Atkinson, Ray, Davis, Linn, Fisher, Curtis Year: 2016 The “Tigard Triangle” is bounded by highways and characterized by auto-oriented land uses in an incomplete street grid. It currently presents a challenge to the City of Tigard, whose vision is to be the most walkable community in the Pacific Northwest. The purpose of the Value of Place project is to develop a plan for improving walkability, safety, comfort, and aesthetics in the Tigard Triangle. In addition, this project was developed to test the application of the State of Place analytical tools to the planning and design challenges faced by the city. This project was conducted under the supervision of Ethan Seltzer, Marisa Zapata, and Susan Hartnett. Close

• 9. [Article] Do TODs Make a Difference? NS Streetcar Line Portland, Oregon

  This analysis was intended to help answer the following policy questions: Q1: Are TODs attractive to certain NAICS sectors? Q2: Do TODs generate more jobs in certain NAICS sectors? Q3: Are firms in TODs ...

  Citation × Citation Citation Abstract Copy Title: Do TODs Make a Difference? NS Streetcar Line Portland, Oregon Author: Liu, Jenny H., Mumuni, Zakari, Berggren, Matt, Miller, Matt, Nelson, Arthur C., Ewing, Reid Year: 2014 This analysis was intended to help answer the following policy questions: Q1: Are TODs attractive to certain NAICS sectors? Q2: Do TODs generate more jobs in certain NAICS sectors? Q3: Are firms in TODs more resilient to economic downturns? Q4: Do TODs create more affordable housing measured as H+T? Q5: Do TODs improve job accessibility for those living in or near them? The first question investigates which types of industries are actually transit oriented. Best planning practices call for a mix of uses focused around housing and retail, but analysis provides some surprises. The second question tests the economic development effects of transit—do locations provided with transit actually experience employment growth? The third question is intended to determine the ability of employers near transit to resist losing jobs; or having lost jobs, to rapidly regain them. The fourth research question confronts the issue of affordable housing and transit. Transit is often billed as a way to provide affordable housing by matching low-cost housing with employment. Yet proximity to transit stations is also expected to raise land values. Proximity to transit, however, may increase actual affordability, regardless of increases in housing costs, because of the reduction in transportation costs. The final research question considers the relationship between workplace and residence locations. To be able to commute by transit, both the workplace and home must be near transit. Effective transit should increase both the number and share of workers who work and live along the transit corridor. Title: Do TODs Make a Difference? NS Streetcar Line Portland, Oregon Author: Liu, Jenny H., Mumuni, Zakari, Berggren, Matt, Miller, Matt, Nelson, Arthur C., Ewing, Reid Year: 2014 This analysis was intended to help answer the following policy questions: Q1: Are TODs attractive to certain NAICS sectors? Q2: Do TODs generate more jobs in certain NAICS sectors? Q3: Are firms in TODs more resilient to economic downturns? Q4: Do TODs create more affordable housing measured as H+T? Q5: Do TODs improve job accessibility for those living in or near them? The first question investigates which types of industries are actually transit oriented. Best planning practices call for a mix of uses focused around housing and retail, but analysis provides some surprises. The second question tests the economic development effects of transit—do locations provided with transit actually experience employment growth? The third question is intended to determine the ability of employers near transit to resist losing jobs; or having lost jobs, to rapidly regain them. The fourth research question confronts the issue of affordable housing and transit. Transit is often billed as a way to provide affordable housing by matching low-cost housing with employment. Yet proximity to transit stations is also expected to raise land values. Proximity to transit, however, may increase actual affordability, regardless of increases in housing costs, because of the reduction in transportation costs. The final research question considers the relationship between workplace and residence locations. To be able to commute by transit, both the workplace and home must be near transit. Effective transit should increase both the number and share of workers who work and live along the transit corridor. Close

• 10. [Article] Retail Rent with Respect to Distance from Light Rail Transit Stations in Dallas and Denver

  A growing body of recent research is challenging the assumptions underlying the half-mile-circle in planning for development around transit stations. In this article we review this literature and extend ...

  Citation × Citation Citation Abstract Copy Title: Retail Rent with Respect to Distance from Light Rail Transit Stations in Dallas and Denver Author: Nelson, Arthur C., Eskic, Dejan, Ganning, Joanna P., Hamidi, Shima, Petheram, Susan J., Liu, Jenny H., Ewing, Reid Year: 2015 A growing body of recent research is challenging the assumptions underlying the half-mile-circle in planning for development around transit stations. In this article we review this literature and extend it to include retail land uses. We estimate the rent premium conferred on retail properties in metropolitan Dallas and metropolitan Denver, both of which have extensive light rail transit systems. We find that consistent with half-mile-circle assumptions, retail rent premiums extend only to about 0.30 mile from transit stations with half the premium dissipating after a few hundred feet and three quarters within the first 0.10 mile. We offer implications for planners and public officials. Title: Retail Rent with Respect to Distance from Light Rail Transit Stations in Dallas and Denver Author: Nelson, Arthur C., Eskic, Dejan, Ganning, Joanna P., Hamidi, Shima, Petheram, Susan J., Liu, Jenny H., Ewing, Reid Year: 2015 A growing body of recent research is challenging the assumptions underlying the half-mile-circle in planning for development around transit stations. In this article we review this literature and extend it to include retail land uses. We estimate the rent premium conferred on retail properties in metropolitan Dallas and metropolitan Denver, both of which have extensive light rail transit systems. We find that consistent with half-mile-circle assumptions, retail rent premiums extend only to about 0.30 mile from transit stations with half the premium dissipating after a few hundred feet and three quarters within the first 0.10 mile. We offer implications for planners and public officials. Close