Susan Clark NRS 509 Nov. 29, 2005

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1 Susan Clark NRS 509 Nov. 29, 2005 The original intent of this project was to look at the role of GIS in the inventory of bicycle and pedestrian facilities. The research, however, indicates a different role for GIS and its application in the field of transportation planning. Three significant uses for GIS are apparent. It has an important use in the research field with its ability to supply objective data as well as substantial databases. Secondly, GIS has a strong application potential in the area of route mapping. Finally, GIS may be used in sub-division design and evaluation. Bicycle and pedestrian research projects have several uses for GIS. Many projects use the software to map the study area. Criteria for selection of the study area differs depending on the subject, but whether the area is selected on the basis of income, neighborhood characteristics, or a specific address of a survey participant, GIS is utilized to create the map. Once this is done, outside databases are connected to the map providing the potential for acquiring extensive data which may then be used as variables. These variables may be read as attributes for each polygon of a study area. They range from population density to ethnicity, income, family status, and even mode of travel to work. Attributes can be provided for slope of a route, land use, topography. Journey to work is especially important in biking and walking studies. Addressing of survey participants can easily be accommodated through use of the TIGER database. Environmental factors such as crime statistics, tax rate, and even local weather characteristics can be accessed through the connection to the correct source. Many bicycle and pedestrian studies involve the decision to bike or walk. In these studies GIS is able to present the objective data amid a collection of perceived images. The choice not to be physically active coincides with areas that are perceived by the residents to be unsafe and unwelcoming to bikers and walkers. However, GIS demonstrates that these neighborhoods are not as inhospitable as perceived. Crime rate is not higher than in other neighborhoods which are perceived as safe. Sidewalks are just as wide. Traffic volume is just as low. The perception is what drives the decision rather than the actual physical characteristics. A second application of GIS in bicycle and pedestrian transportation planning is route planning. Route planning may be accomplished for various reasons. The Safe Routes to School Program is a national program to encourage U.S. children to walk or bike to school. If safety is the criteria for route planning, the GIS database is organized around a collection of traffic data such as Average Daily Traffic, crime rate, number of intersections, number of travel lanes, and presence of bike lanes among others. With analysis of these variables, a safe route may be plotted from the origin of the bike trip to the destination. Distance of each route can be determined and then routes may be compared for a choice of the safest, but yet most direct route. Route planning may also revolve around a selection of points, or destinations. Although this is a common application in vehicle transportation planning, it is not common practice for bicycling and walking. Biking and walking involve consideration of

2 factors which are not as important in vehicle routing such as road grade and intersection numbers and detail. Change in elevation of a route may not have any significant effect on the choice to drive it, but it has a great of influence on the choice to bike or walk it. The ease of incorporating these factors into the decision is much greater with use of GIS. Therefore in route planning there are two elements of GIS. One is the set of spatial data and the other is spatial analysis. Urban design and landscape design benefit from a third application of GIS. In addition to mapping abilities and accessibility to extensive databases, GIS may be used for spatial analysis of walking and biking routes within a development, either new or existing. To encourage walking activity in particular, it is important to design routes with the walker in mind. With studies showing that people will not walk more than ¼ mile, designers are able to measure distances within a proposed development or project to analyze which has the shortest routes to destinations. Destinations considered are schools, transit stops, and open spaces. These analyses may be done speedily and provide opportunities for the designer to quickly assess the walkability of the development. Databases which will be necessary for the three applications of GIS in bicycle and pedestrian planning include government, state, and local sources. Census data, both polygon and line, provide information on the population characteristics and addressing. A National elevation database is useful as well as municipal resources such as crime statistics and parcel information, including property tax amount. State data includes traffic information such as average daily traffic, number of lanes, and intersections. Inventory of bicycle and pedestrian facilities using GIS is a practice used by some state Departments of Transportation. The application which I describe here could apply to Vermont AOT which is planning to develop an inventory of facilities. Visuals of sidewalks, bicycle lanes, and shared use recreational paths are recorded on video tape. A van is driven over every state road. The right lane is video recorded with two cameras, one aimed directly on the lane in front, the other off to the right side. The width of the sidewalk can then be measured with a software program called Surveyor. The lines representing sidewalks, lanes, and paths can then be digitized to a layer in GIS using the state road network map as the base. Attributes for each segment can then be entered which would include sidewalk or lane width, condition, and materials. Crash data could be entered in as point data and identified as to the type and cause. This could then be used in a safe routes planning application. Although GIS has had widespread use in motor vehicle traffic planning, its full potential has not been realized in the area of bicycles and pedestrians. Many of the same applications can be used to plan biking and walking routes as are now used in planning for roads and highways. The difficulty is in adapting the application to fit a much different mode of transportation, but with promotion of the healthy lifestyle of a biker or pedestrian, it is becoming more common.

3 Annotated Bibliography Moudon, Anne Vernez, Chanam Lee, Allen D. Cheadle, Cheza W. Collier, Donna Johnson, Thomas L. Schmid, and Robert D. Weather Cycling and the Built Environment. Transportation Research Part D: Transport and Environment. 10 (3) GIS is the base for this statistical study on variables which affect the number of people choosing to cycle in King County, Washington. The spatial frame is created in GIS and consists of polygons of various land uses within a 240m buffer. Subjective variables are considered, such as perception of safety. GIS provides the objective data for the study such as land use, bus rider ship, and distance to neighborhood centers. It also provides information on topics such as population density, street block size, sidewalk length, traffic volume and speed, topography, and others. GIS provides the ability to study the number of times individuals ride bicycles during a typical week with respect to these independent variables. Crane, Randall, and Crepeau, Richard Does Neighborhood Design Influence Travel?: A Behavioral Analysis of Travel Diary and GIS Data. Transportation Research Part D: Transport and Environment. 3 (4) Crane and Crepeau have developed this study in response to the assertions of the most up to date urban planning model, New Urbanism. The study is a look at land use and travel networks to see if, in fact, they do have an effect on mode of travel choices. GIS in this application is used to eliminate the concerns about neighborhood definition. GIS is implemented to map the study areas by drawing a buffer around each surveyed household and studying the neighborhood characteristics within that buffer. Further explanation about the use of GIS would be helpful for designing future studies. No comments were made on the ability of GIS to develop objective criteria from databases. A question remains as to the extent of the use of GIS in the study. Aultman-Hall, Lisa, Matthew Roorda, and Brian W. Baetz Using GIS for Evaluation of Neighborhood Pedestrian Accessibility. Journal of Urban Planning & Development. 123 (1) 10. The goal of this paper is to promote the use of GIS in the design of sub-divisions to promote walking within a development GIS is the tool which makes the comparison of various sub-division designs possible. The variable which has the greatest influence on choice of walking to a destination is distance. People will not choose to walk if the distance is over 400m(approximately ¼ mile). GIS was used to measure distances to three destinations,: school, open space, and transit stops, for three different sub-division layouts. By measuring the distances, GIS makes the decision between layouts easier. Pikora, Terri Developing a Reliable Audit Instrument to Measure the Physical Environment for Physical Activity. American Journal of Preventive Medicine. 23 (3) 187.

4 This study which was conducted in Perth, Australia, was completed to test an instrument which measures environmental factors which have an effect on the decision to engage in certain physical activities such as biking and walking. Three sources of data were needed for this study. One set collected information using the instrument under study. The second set came from outside sources such as traffic numbers. GIS provided the third set which included information on the destination points. GIS ArcView 3.2 was used to create maps for the study areas. This article was not very helpful, not only in the discussion of the application of GIS, but in the evaluation of the instrument under study as well. Ehlers, Manfred, Stefan Jung, and Katrin Stroemer Design and Implementation of a GIIS Based Bicycle Routing System for the World Wide Web (WWW). Symposium on Geospatial Theory, Processing and Application. Ottawa. Commission IV, WG IV/6. This conference paper is a description of a GIS program for designing bicycling routes in Germany. The process uses an Internet Map Server and the user may access the program via the internet. Routes are plotted based on sites to be included in the tour. The user chooses the desired sites to be incorporated into a route. The request is sent to the Application Server which then distributes it to the correct Spatial Server. The response comes back in HTML format. The user does not need GIS on his/her computer. Standardized maps are also available and the goal is to create bicycle-based navigation units which would direct the user. Huang, Yuanlin and Gordon Ye Selecting Bicycle Commuting Routes Using GIS. Berkeley Planning Journal Huang and Ye of Berkeley have established a model for using GIS to plan bicycle routes within a metropolitan area. They establish that planning bicycle routes differs from auto routes and involves more variables. These variables, grade, travel time, auto traffic, and road surface conditions, are formulated from factors which may be obtained from a variety of publicly available databases. These variables are then combined to determine an impedance factor for roadway segments. Origination and destination points were identified to outline the trip routes which are recommended. The GIS process is twofold. It first involves the creation of the databases and secondly, runs the spatial analysis of the bicycle routes. Wilson, Dawn K. Ph.D., Karen A. Kirtland, Ph.D., Barbara E. Ainsworth, Ph.D., M.P.H., and Cheryl L. Addy, Ph.D., Socioeconomic Status and Perception of Access and Safety for Physical Activity. Annals of Behavioral Medicine. 28 (1) GIS was able in this study to present objective data for factors which address perception of an area. Perception in low income areas was that the area was not attractive, had greater vehicle traffic, and was less conducive to physical activity. GIS data revealed that this was not true. It is the perception of these factors which is the base of the study. Low income areas were compared with high income areas. GIS data revealed the

5 factors dealing with walking facilities were equal across the two income levels. Perception was not equal. Accessibility to trails was the only difference with low income levels having fewer trails.