MEASURING THE QUALITY OF THE PEDESTRIAN ENVIRONMENT: TOWARDS AN APPROPRIATE ASSESSMENT METHODOLOGY Prepared by Andrew Devlin MA Candidate Presented to Dr. Lawrence Frank PLAN 548Q School of Community and Regional Planning 7 March 2008 The University of British Columbia
ABSTRACT In order to plan for more walkable environments, methods are required that allow planners and decision-makers to effectively identify and assess the elements of the built environment that support or detract from walking. The existing pedestrian levelof-service methodology is critiqued and demonstrated to be an inappropriate tool to assess the pedestrian environment. A more accurate and sensitive tool would incorporate and account for the various micro-scale environmental factors that define the walking environment. To improve existing assessment processes, municipalities will be required to identify what elements need to be measured, how to measure these elements and, finally, incorporating them into an appropriate assessment framework. The literature and progressive practical examples like the For Collins pedestrian LOS methodology provide a framework for how to develop an appropriate tool. Page 2
TABLE OF CONTENTS INTRODUCTION 4 DEFINING AND DISSECTING THE PEDESTRIAN ENVIRONMENT 4 MEASURING THE PEDESTRIAN ENVIRONMENT 6 Existing Approach 6 Strengths and Weaknesses of Existing Approach 7 ARTICULATING A NEW DIRECTION 8 What Needs To Be Measured? 9 How Should These Elements Be Measured? 9 What Should A New Methodology Look Like? 10 CASE STUDY 11 Fort Collins, Colorado A Progressive Pedestrian LOS 11 CONCLUSIONS 12 REFERENCES 12 Page 3
INTRODUCTION With the explosion of Smart Growth, New Urbanism and neo-traditional urban design ideologies during the past decade, it has become common for many municipal governments and planning agencies to cite their commitment towards planning for the pedestrian and nonmotorized traveler (Benfield, 2003). In order to appropriately plan for more walkable environments, methods are required that allow planners and decision-makers to effectively identify and assess the elements of the built environment that support or detract from walking. (Muraleetharan and Hagiwara, 2007). The quality of the pedestrian environment has been measured for many years throughout North American and Europe using the Level-of-Service (LOS) approach. Debate exists, however, over the appropriateness of existing LOS methods to capture the numerous factors that contribute to how walkable a streetscape may be perceived to be (Clifton et al., 2007). As a result, there is concern that inappropriate policy and investment initiatives will be directed at the pedestrian environment (Landis et al., 2001). Recognizing this situation, the goal of this paper is to summarize the dialogue and debate on pedestrian level of service measurements and lend ideas on how the process can be improved. The paper begins with a discussion on the myriad of factors and elements that may contribute to a walkable environment. It then draws on these to assess and critique the existing methodologies that measure the quality of the pedestrian environment. The last section will focus on identifying shortcomings of the existing tools and measures and ways to improve the process will be discussed and recommended. DEFINING AND DISSECTING THE PEDESTRIAN ENVIRONMENT The literature on what elements come together to define a walkable urban environment is quite extensive. A majority of this research limit measures of interest to more macro-scale elements such as land use mix, density, and street patterns (Frank and Engelke, 2001; Greenwald and Boarnet, 2001; Handy et al., 2002; Saelens et al., 2003). This body of work has generally found that areas with higher residential and commercial densities, higher intersection densities, and a functional mixing of land uses in close proximity to where people live and work are associated with higher levels of walking and cycling (Frank and Pivo, 1994; Frank et al., 2005). What these Page 4
studies fail to capture, however, are the micro-scale environmental elements that frame the suitability for walking in a given area. These may include the street façade and sidewalk treatments, building site design and street furniture (Figure 1) (Zacharias, 2001). There is an emerging argument that these elements and other like them have a strong influence on how the pedestrian perceives the walking environment (Giles-Corti and Donovan, 2003). This argument is justified by Rapoport (1987) who states that because pedestrians move at a much slower pace than vehicles they are more aware and sensitive to their surroundings. As a result, pedestrians require a high number of noticeable differences in the form of street furniture, destinations, building types and styles and signage to make the walking environment enjoyable. Figure 1: Pedestrian Friendly Street in Aspen, CO. Note pedestrian-scale signage, building setback, placement of trees and furniture and sidewalk treatment. Source: PPS (http://www.pps.org). A number of papers have attempted to articulate and assess the relative influence of various micro-scale built environment elements that may affect a pedestrian s assessment of the quality of the walking environment. Craig et al. (2002) describes 18 elements that may lend to creating a walkable environment. These included visual interest (i.e. type and variety of buildings and building design), traffic threats (i.e. speed of and separation from traffic), and the inclusiveness of pedestrians (i.e. pedestrian-oriented buildings, signage and amenities). Owen et al (2004) developed a comprehensive list of over 60 micro-scale elements that influence walking, including safety from traffic, presence of continuous sidewalks, presence of street crossings, degree of crowding, sidewalk environment (i.e. seating, garbage can, planter boxes), route directness, site design, and visual interest and stimuli. Pikora et al (2002) also identifies over 40 environmental components that contribute to overall functionality, safety, aesthetics, and destinations. The full lists of environmental Page 5
elements and components identified by Craig et al. (2002) and Owen et al. (2004) are found in Appendix A. Studies have been conducted that offer empirical evidence of the influence of micro-scale environmental elements on defining the quality of the pedestrian environment. Research by Humpel et al. (2002), Giles-Corti and Donovan (2003), and Saelens et al. (2003) found highly walkable environments are positively correlated with strong aesthetic qualities, higher perceptions of pedestrian safety and access to appropriate facilities. Brownson et al. (2004) surveyed residents in the San Diego area and demonstrated that characteristics like a pedestrian-oriented walking environment, stimulating neighbourhood aesthetics and neighbourhood safety contributed to a more enjoyable walking environment. These studies and other like them support the idea that what defines the quality of the pedestrian environment is complex. The presence and quality of these types of features needs to be assessed in order to better plan for successful pedestrian environments. MEASURING THE PEDESTRIAN ENVIRONMENT Existing Approach The most widely used method to assess the quality of the pedestrian environment is the pedestrian Level-of-Service (LOS) measurement (Kerridge et al., 2001). This method employs a letter scale from A to F to measure and describe the overall walking conditions of the pedestrian environment. An LOS A is considered an ideal environment while LOS F would be the worst or most unfitting for a pedestrian (Fruin, 1971). The most common application of the pedestrian LOS methodology is to measure the capacity and flow characteristics of pedestrian facilities (Petritsch et al., 2006). Here, sidewalks and pathways that have unimpeded flow and an abundance of additional capacity are considered to be the most ideal environments for pedestrians (see Figure 2). Conversely, those streetscapes or intersections characterized by high degrees of crowding are deemed to be ill suited for optimal pedestrian movement. Another common application of the pedestrian LOS methodology is to assess the pedestrian environment in terms of the ease with which streets can be crossed (presence and timing of crossing zones) and sidewalk and Page 6
pathway continuity (Dixon, 1996). Where more of these features exist, the better the environment is deemed to be pedestrian-friendly. These methods of assessing the built environment in terms of flow, movement and capacity have been normalized in the Highway Capacity Manual (HCM), the industry standard guidelines for evaluating the pedestrian environment (TRB, 2000). Indeed, many major United States metropolitan areas including New York City and Baltimore have adopted this methodology into their practical planning practice to assess and better plan for the pedestrian environment (Baltimore Metropolitan Council, 2004; NYC DCP, 2006). Strengths and Weaknesses of Existing Approach The more common pedestrian LOS applications outlined above have several advantages which makes their appealing to many municipalities and planning agencies. First, these methodologies are rather simple. It is relatively easy, for instance, to collect and assess data on sidewalk continuity, location of crosswalks and general flow characteristics (Petritsch et al., 2006). Second, the standardization of the pedestrian LOS that assesses flow, movement and capacity characteristics in the HCM allows planners and decision-makers to utilize pre-developed ways of assessing data and allows for easy comparison of LOS ratings from a certain place and time and other location (NYC DCP, 2006). Figure 2: Images of pedestrian LOS standards contained in the Highway Capacity Manual. LOS A is defined as the best condition. LOS F is considered the worst. Source: HCM, 2000. Numerous deficiencies and criticisms of the existing assessment approach have been identified. Research by Khisty (1994), Jaskiewicz (1999), Phillips and Guttenplan (2003), and Muraleetharan and Hagiwara (2007) points out that the existing pedestrian LOS methodologies used in many North American jurisdictions are Page 7
inaccurate in that they do not reflect and incorporate other important elements that aid in defining how walkable an environment is from the pedestrians perspective. These include the myriad of factors discussed in the previous section and found in Appendix A. By not incorporating and assessing these additional measures, it can be argued that the existing, more common pedestrian LOS framework being used may actually reinforce the perpetuation of plans, policies and initiatives that do not favour walking and nonmotorized transportation. For instance, using these measures, more traditional suburban streets and arterials can be developed with a continuous sidewalk or pathway system and a large number of strategically placed crosswalks can register a high level of service rating although walking may actually be quite impractical and unexciting due to wide road widths, homogenous and uninteresting site design, and the lack of pedestrian amenities and signage that characterize many traditional suburban developments (Landis et al., 2001). Under current methods, street furniture like benches, signage and planter boxes are actually considered barriers that impede pedestrian flow and therefore contribute negatively to a successful pedestrian environment (NYC DCP, 2006). It would appear, then, that a complete shift in thinking about the pedestrian environment is required on the part of municipalities and planning agencies to develop and use more accurate and appropriate LOS measurements. ARTICULATING A NEW DIRECTION Despite the abundance of criticism, much of the work directed at improving the pedestrian LOS methodology is focused on strengthening the current applications of assessing pedestrian flow and the availability of pedestrian facilities and infrastructure (Baltes and Chu, 2002). Although important in certain respects, this work does little to push assessment methodologies towards a more comprehensive framework like that called for by Rapoport (1987). Where research has been directed at explicitly articulating a more appropriate way for assessing the quality of the pedestrian environment, it is scattered throughout the literature (Gallin, 2001). This section will draw on this body of work to bring together and articulate the various ideas for improving the pedestrian LOS measurement. Page 8
What Needs To Be Measured? There are a number of objective and subjective elements that contribute to defining the pedestrian environment (see Appendix A). It is impossible to measure, let alone know, every factor that is most important to residents who walk or cycle. Although there are currently no standard or common ways of establishing what these factors (Handy and Clifton, 2001), the literature points to several ways of collecting this information. Surveys, interviews and focus groups, for instance, can be used determine what certain streetscape elements are the most important (or not) for walking environments (Pikora et al., 2003). Surveys can be developed to ask people to consider aspects of the built environment that might support or impede walking in their neighbourhood and how the design of these and other places may be improved to facilitate walking (Day et al., 2006). Surveys, however, may take a substantial amount of time and money to undertake, something many municipalities may not have (Day et al., 2006). In their place, municipalities and agencies may turn to the literature. This paper has demonstrated that many studies have looked at which elements lend the most influence to defining walkable environments. These could be used as a foundation for what a municipality or agency may want to assess. The relatively low cost of this option may make it more appealing for many municipalities. How Should These Elements Be Measured? Many of the elements identified by pedestrians that define the quality of the walking environment can be difficult to quantify or measure (Khisty, 1994). For instance, issues may arise in how to effectively assess the visual stimulus or aesthetical qualities of a streetscape. The literature provides an established body of work that offers numerous ways to quantify or measure these subjective qualities. For instance, pedestrian safety may be measured in terms of amount of quality of pedestrian-scale lighting, the presence of clear sightlines, or the amount of street parking separating pedestrians from traffic (Hess et al., 1999; Landis et al., 2001; Chu et al., 2004). Visual and aesthetic quality may be measured by the presence of historical buildings and unique architecture, public art and street furniture and the building setback from the sidewalk/street (Gallin, 2001). Field surveys undertaken by municipal or agency staff or pedestrians themselves may be used to identify and record the pertinent built Page 9
environment characteristics (Day et al., 2006). It is also possible that many municipalities or agencies will already have information on many of these elements scattered throughout various departments (Handy and Clifton, 2001). In this case, it would be a matter of collecting all of the pertinent data and standardizing it into a format that will allow for a meaningful analysis. Geographic Information Systems (GIS) can be used to efficiently map and analyze the distribution of key elements like street furniture, historical buildings, crosswalks and sidewalks, and areas of on-street parking an create databases of the features (Aultman-Hall et al., 1997). Lee and Moudon (2006) used GIS to capture and map various environmental elements including the location of trees and street furniture, crosswalks and topography in a study that explored the correlates of walking and cycling. Combining different map layers of various features in a GIS enables the planner or decision-maker to produce a visual representation of where environments are more conducive to pedestrian activity and those that are not and require more immediate attention. What Should A New Methodology Look Like? The potential exists to identify and measure additional elements and factors that contribute to the quality of the pedestrian environment in a pedestrian LOS assessment tool. Recent work, however, has explore the relevance of the traditional LOS scale of measurement to effectively and accurate assess the myriad of factors that may define the pedestrian environment. Phillips and Guttenplan (2003), for instance, lament that agencies should not focus efforts to utilize the broad LOS A-F categorization. These categories often aggregate and combine various elements that contribute to a certain theme or major characteristics like safety or visual aesthetics and apply a letter grade to each one. The authors note that a variety of factors that influence the quality of the pedestrian environment may not readily lend themselves to such an aggregated and rigid scale of measurement and therefore call for tools that assess the overall quality of the pedestrian environment. Environmental audit instruments offer a potentially more comprehensive and flexible alternative. These tools allow the user to rate and evaluate individual elements of the built environment that are defined as influencing the quality of the streetscape. (Clifton et al., 2007). In this sense, they allow planners and decision-makers to pinpoint those exact elements that contribute to or detract from a walkable Page 10
streetscape. Audit instruments have been developed and implemented in Australia (Pikora et al., 2002) and in the United States (Day et al., 2006; Clifton et al., 2007) that allow the user to evaluate various elements of the built environment. The testing of these instruments has revealed these instruments to be relatively consistent, reliable and easy to use (Moudon and Lee, 2003). Given their potential to include countless variables that may be evaluated these instruments may result in more detailed characterization of the environment. As a result, however, they may require more time, resources and commitment to develop and administer (Clifton et al., 2007). An example of an environmental audit instrument developed by Clifton et al. (2007) is found in Appendix B. CASE STUDY Fort Collins, Colorado A Progressive Pedestrian LOS The pedestrian LOS developed for Fort Collins, Colorado embodies many of the elements discussed in the previous section and serves as a practical example of the potential for developing and implementing progressive tools to assess the quality and performance of the pedestrian environment. In 1996, the City of Fort Collins developed a comprehensive pedestrian plan that effectively placed the needs of the pedestrian as a primary planning goal for the City. A new pedestrian LOS was seen as a key tool that would aid the City in analyzing existing pedestrian conditions and proposed public and private improvement projects (City of Fort Collins, 1996). The LOS was developed through extensive consultation work. Pedestrian focus groups, Fort Collins Transportation Board officials, Street Standards Committee, and those in attendance at numerous local workshops and outreach initiatives were allowed to actively contribute in the planning and development process. The final product assesses pedestrian conditions based on directness (measurement of walking trip length), continuity (measurement of completeness of sidewalk and pathway system), street crossings (measurement of pedestrian safety in crossing a street), visual interest and amenities (measurement of the pedestrian system attractiveness and features) and security (measurement of the pedestrian s sense of security). A variety of variables like number and location of crosswalks, building setbacks, street furniture and pedestrian lighting are included under each category. Page 11
The city also established threshold values for each category of measurement. These thresholds define the minimum acceptable standard for each element. They also have strong policies that require new public and private developments as well as major street improvements and redevelopment should adhere to the pedestrian LOS standards and attempt to attain the required threshold values. The Fort Collins Pedestrian LOS included in this paper in Appendix C. CONCLUSIONS Existing pedestrian LOS methodologies are entrenched in an ideology based on ease of movement and efficiency of the pedestrian system. These initiatives neglect to account for other subjective factors that are proving to be influential in defining the quality of the walking environment and, as a result, may lend to the perpetual (re) development of truly unwalkable spaces. This paper has demonstrated that potential exists to develop an appropriate quality of service assessment methodology for the pedestrian environment. To do so, three key aspects must be overcome. These are identifying what elements need to be measured, how to assess the elements and incorporating these into an appropriate assessment framework. The literature and progressive practical examples like the For Collins pedestrian LOS methodology provide a framework for how to develop an appropriate tool. It should be acknowledged, however, that substantial efforts would be required on the part of municipalities and planning agencies to initiate and undertake these projects. If municipalities wish to strive towards creating more walkable spaces, the complexity and challenge of developing an appropriate assessment framework should not deter them. REFERENCES Aultman-Hall, L., Roorda, M., & Baetz, B. W. (1997). Using GIS for evaluation of neighborhood pedestrian accessibility. Journal of Urban Planning and Development, 123(1), 10-17. Baltes, M. R., & Chu, X. (2002). Pedestrian level of service for midblock street crossings. Transportation Research Record, 1818, 125-133. Page 12
Baltimore Metropolitan Council. (2004). Bicycle level of service update & pedestrian level of service evaluation. Accessed February 2008 from the World Wide Web: http://www.baltometro.org/reports/bikepedlos.pdf Benfield, F. K. (2003). Solving sprawl: Models of smart growth in communities across America. Washington, D.C.: Island Press. Brownson, R. C., Chang, J. J., Eyler, A. A., & Ainsworth, B. E. (2004). Measuring the environment for friendliness toward physical activity: A comparison of the reliability of 3 questionnaires. American Journal of Public Health, 94(3), 473-483. Chu, X., Guttenplan, M., & Baltes, M. R. (2004). Why people cross where they do: The role of the street environment. Transportation Research Record, 1878, 3-10. City of Fort Collins. (1996). Pedestrian Level of Service 1996. Accessed February 2008 from the World Wide Web: http://fcgov.com/transportationplanning/pdf/levelofservice.pdf Clifton, K., Livismith, A., & Rodriguez, D. (2007). The development and testing of an audit for the pedestrian environment. Landscape and Urban Planning, 80(1-2), 95-110. Craig, C. L., Brownson, R. C., Cragg, S. E., & Dunn, A. L. (2002). Exploring the effect of the environment on physical activity: A study examining walking to work. American Journal of Preventive Medicine, 23(2S), 36-43. Day, K., Boarnet, M. G., Alfonzo, M., & Forsyth, A. (2006). The Irvine ÄìMinnesota inventory to measure built environments development. American Journal of Preventive Medicine, 30(2), 144-152. Dixon, L. B. (1996). Bicycle and pedestrian level-of-service performance measures and standards for congestion management systems. Transportation Research Record, 1538, 1-9. Frank, L., & Engelke, P. (2001). The built environment and human activity: Exploring the impacts of urban form on public health. Journal of Planning Literature, 16(2), 202-218. Frank, L., Schmid, T., Sallis, J., Chapman, J., & Saelens, B. (2005). Linking objectively measured physical activity with objectively measured urban form: Findings from SMARTRAQ. American Journal of Preventive Medicine, 28(2), 117-125. Frank, L. D., & Pivo, G. (1994). Impacts of mixed use and density on utilization of three modes of travel: single-occupant vehicle, transit, and walking. Transportation Research Record, 1466, 44-52. Fruin, J. (1971). Pedestrian Planning and Design. New York: Metropolitan Association of Urban Designers and Environmental Planners, Inc. Page 13
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Muraleetharan, T., & Hagiwara, T. (2007). Overall level of servce of urban walking environment and its influence on pedestrian route chice behavior: Analysis of pedestrian travel in Sapporo, Japan. Transportation Research Record, 2002, 7-17. New York City Department of City Planning (NYC DCP). (2006). NYC Pedestrian Level of Service STudy - Phase I, 2006. Accessed February 2008 from the World Wide Web: www.nyc.gov/html/dcp/html/transportation/td_ped_level_serv.shtml Owen, N., Humpel, N., Leslie, E., Bauman, A., & Sallis, J. (2004). Understanding environmental influences on walking: Review and research agenda. American Journal of Preventive Medicine, 27(1), 67-76. Petritsch, T. A., Landis, B. W., McLeod, P. S., & Huang, H. F. (2006). Pedestrian level-ofservice model for urban arterial facilities with sidewalks. Transportation Research Record, 1982, 84-89. Phillips, R., & Guttenplan, M. (2003). A review of approaches for assessing multimodal quality of service. Journal of Public Transportation, 6(4), 19. Pikora, T. (2003). Developing a framework for assessment of the environmental determinants of walking and cycling. Social Science & Medicine, 56(8), 1693-1703. Pikora, T., Bull, F. C. L., Jamrozik, K., & Knuiman, M. (2002). Developing a reliable audit instrument to measure the physical environment for physical activity. American Journal of Preventive Medicine, 23(3), 187-194. Rapoport, A. (1987). Pedestrian Street use: Culture and perception. In Anne Moudon (ed) Public Streets for Public Use. New York: Van Nostrand Reinhold. Saelens, B., Sallis, J., Black, J. B., & Chen, D. (2003). Neighborhood-based differences in physical activity: An environment scale evaluation. American Journal of Public Health, 93(9), 1552-1558. Saelens, B., Sallis, J., & Frank, L. (2003). Environmental correlates of walking and cycling: Findings from the transportation, urban design, and planning literature. Annals of Behavioral Medicine, 25(2), 80-91. Transportation Research Board (TRB). (2000). Highway Capacity Manual. Washington, DC: Transportation Research Board, National Research Council. Zacharias, J. (2001). Pedestrian behavior pedestrian behavior and perception in urban walking environments. Journal of Planning Literature, 16(1), 3-18. Page 15
APPENDIX A BUILT ENVIRONMENT CHARACTERISTICS Page 16
Source: Craig et al. (2002). Page 17
Source: Owen et al. (2004). Page 18
APPENDIX B SAMPLE ENVIRONMENTAL AUDIT INSTRUMENT Page 19
Source: Clifton et al. (2007). Page 20
APPENDIX C FORT COLLINS, CO PEDESTRIAN LOS Page 21
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