Redesigning Silicon Valley’s Bus Routes
I recently completed my Bachelor’s degree at San Jose State University in Geography with minors in GIS and Urban Studies. In the course of my studies, the GIS project that I found most edifying was in my Advanced GIS for Urban Planning class because it involved working with an outside client: the Santa Clara Valley Transportation Authority (VTA). This large agency coordinates public transportation in the vast Silicon Valley region. The agency is completing a significant redesign of its entire bus route network, and the planning team solicited input from our class on the effectiveness of the proposed rerouting to ensure maximum access for residents of affected neighborhoods. This semester-long project gave my team an opportunity to create a digital map book that categorized and labeled each new bus route as well as the "walksheds" or catchments around bus stations using ArcGIS Network Analyst and Data Driven Pages, as shown in figure 1.
Our professor, Richard Kos, helped us launch the project. We started by meeting with our clients, Jay Tyree and Esther Jung, at their VTA office. They explained that the bus station location redesign project would be triggered by the launch of BART service (the Bay Area Rapid Transit public transportation system) to northeastern San Jose (now planned for late 2019). They asked us to create quarter mile and half mile catchments (walksheds) for each newly redesigned station location using the ArcGIS Network Analysis toolset.
Ms. Jung gave us more detail about the project by explaining the VTA route numbering conventions; for example, 200 for school bus routes, two digits for regular routes, and 66L for an extended route. Once we received the data from her, my team created a geodatabase and organized all bus stop and route data within it. Then we checked the attribute tables to verify that all the data we entered was accurate, and made minor changes as needed. With the data gathered, we also created a network dataset, a foundational data type necessary to network-based analysis. Professor Kos guided us through this process to ensure that our quarter- and half-mile catchments would be properly generated by traveling away from the bus station locations along the road system (as opposed to a straight-line, “as the crow flies” distance measurement, which doesn’t reflect the way people actually move in the area). Check-in meetings with VTA staff further ensured that our progress was accurate and on track to timely completion.
Since VTA required us to organize our final maps into a convenient PDF booklet, we used the ArcGIS feature known as Data Driven Pages. Once we studied how to use it properly, we experimented with its many options, determining which VTA data attributes would be most suitable to produce one bus route per PDF page. Eventually we decided to settle for putting the main route in the center of the page, with surrounding routes in the vicinity. Examples are shown in figures 2 and 3.
Ultimately, we determined that the “Page Definition Tool” would produce the maps we needed, and we also learned how each route could be depicted in both the “inbound” and “outbound” directions. Our final step was to apply cartographic touches to ensure that the maps were clear and easy to read. For example, since the yellow catchment overlapped with the school color routes, we experimented with blue and light blue catchment areas instead, as shown in figure 4. Later, we thought that we could just make the yellow school routes have the thinnest width so that it would seen on top of other broader routes on relevant pages of the map book.
This project was challenging but extremely rewarding, and the whole process was quite a learning experience! We appreciated all the support we received from Mr. Tyree and Ms. Jung at VTA and, of course, from Professor Kos. Due to their guidance and support, our GIS skills flourished and we learned new tools for executing this project. Furthermore, our insight into transportation planning widened by seeing how the VTA system works and how it intends to serve the residents of Silicon Valley.
Aseem Mogre is currently enrolled as a part-time graduate student in the online MS GIS program at Johns Hopkins University. He can be reached at email@example.com.