PLAN 626: Advanced GIS in Landscape Architecture and Urban Planning
Applying GIS Technology to Improve Transit Accessibility -Lawrence Marcus, Jose Rodaniel Cruz Journal Article Review (Presentation) Submitted by – Avinash Shrivastava
City of Rockville, Maryland • PROBLEM: Traffic congestion • GOAL: To improve transportation networks • STRATEGY: To fight congestion by taking the battle off the streets and focusing on the promotion of alternative modes of transportation. • FOCUS: Applying GIS technology to map transit and pedestrian networks. • ACTION: Run distance and travel time analyses.
NETWORK ANALYSIS • DATA COLLECTION: Existing GIS layers (centerlines, bus routes, sidewalks) Using GIS, transportation networks were developed around these layers. – Transit Lines Network – Sidewalk (Pedestrian) Network and – Location of Bus Stops
• ANALYSIS: Using GIS, which supports Network Analyst, the aforementioned layers were integrated to view the actual scope and efficiency of the Rockville transit system.
OBJECTIVE 1: Maximize Walk-Accessible Transit Service To City Residents
Transit Buffer Area Transit buffer areas are formed by constructing a circular buffer with a radius of 0.25 miles (0.4 km), regardless of network connectivity.
Problem with ‘Transit Buffer Area’ Assumption - All residents can walk “as the crow flies” to a transit stop. As a result, this map indicates portions of unconnected, parallel streets within 0.25 mi (0.4 km) of a bus stop within the shaded buffer area.
Solution is ‘Transit Catchment Area’ This map displays pedestrian routes, color-coded by travel time. Areas without color represent problem locations. Transit Catchment Area Every portion of street segment that is connected to and within 0.25 mi (0.4 km) of a bus stop. If a street parallels a bus route at a distance of less than 0.25 mi (0.4 km) but is not connected to the street near the bus route, it is excluded from the catchment area.
On a City-wide scale.. • Real-world view of actual walk sheds available to access transit service. • Areas outside blue shaded areas are those beyond ¼ mile access to transit service. ESTIMATE POPULATION INACCESSIBLE TO TRANSIT: 23 percent (11,314)
OBJECTIVE 2: Increase the Number of Residents within a 10-Minute Travel Time to a Metrorail Station, using the Local Bus Service • To evaluate access to the Rockville Metrorail station, the GIS model was used to integrate the results of Objective 1 with transit performance. • Transit lines are colorcoded, reflecting the travel time to the Rockville Metrorail station.
OBJECTIVE 3: Maximize the Transit Frequency of Service
Finally, the quality of transit service in Rockville was assessed using data on the frequency of transit service and the population/employment base.
RECOMMENDATIONS Modifications to the transit system: (a) Modify the route(s), (b) Add or change bus stop locations, (c) Add shuttle service.
Professional Paper Topic: Facilitating trips to key destinations (B-CS area), by re-routing the Texas A & M University buses.
THANK YOU
Applying GIS Technology to Improve Transit Accessibility Lawrence Marcus, Jose Rodaniel Cruz Journal Article Review (Notes)
Applying GIS Technology to Improve Transit Accessibility - Lawrence Marcus, Jose Rodaniel Cruz
SLIDE 2 City of Rockville, Maryland •
PROBLEM: Traffic congestion is one of the biggest problems throughout the United States.
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Now the QUESTION is how can a small city like City of Rockville, Maryland confront this problem and work to improve the quality of its transportation system?
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To answer this question, the City came up with an approach to fight congestion by taking the battle off the streets and focusing on the promotion of alternative modes of transportation.
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The main emphasis of this study and analysis was to apply GIS technology to map transit and pedestrian networks and how this data could be subsequently used to study the City’s transit system as a whole.
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In order to do this the city ran distance and travel time analyses on vehicular, bicycle, pedestrian and transit networks.
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The data was collected and the existing GIS layers were obtained from Montgomery County.
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Then by using GIS and a combination of aerial photography and actual surveys, transportation networks were developed around these layers.
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These transportation networks were:
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Transit Lines Network: In a line segment, the (assigned) difference in time from one time point to the next is a variable which represents the time cost that Network Analyst uses in running the network.
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Sidewalk (Pedestrian) Network: The sidewalk GIS network was critical to this study because sidewalks are the main access methods for the bus stops. This network was constructed by tracing over aerial photography of the City and field checking the results.
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Location of Bus Stops: The assigned bus stop ID was entered as an attribute for each stop. With these IDs, staff was able to link the networks created in the City’s GIS to existing County databases. These databases contained information for each bus stop such as bus stop amenities and bus ridership information.
To view the actual scope and efficiency of the Rockville transit system, these layers were then integrated using GIS, which supports Network Analyst.
Journal Article Review (Notes), PLAN 626: Advanced GIS in Landscape Architecture and Urban Planning, Submitted By – Avinash Shrivastava Page 1
Applying GIS Technology to Improve Transit Accessibility - Lawrence Marcus, Jose Rodaniel Cruz
SLIDE 4 Objective 1: Maximize WalkAccessible Transit Service to City Residents So the city created a map which displays route walk buffers, assuming ¼ mile distance for each bus stop and 7/10 mile distance for Metrorail stations. Yellow areas represent locations without walkable service. Transit buffer areas are formed by constructing a circular buffer with a radius of 0.25 miles (0.4 km), regardless of network connectivity.
SLIDE 5 Problem with ‘Transit Buffer Area’: This map was constructed based on the assumption that all residents can walk “as the crow flies” to a transit stop. As a result, this map indicates portions of unconnected, parallel streets within 0.25 mi (0.4 km) of a bus stop within the shaded buffer area.
SLIDE 6 Solution is ‘Transit Catchment Area’ Transit Catchment Area: This map excludes all the areas and the streets which are not connected to the street near the bus route. And the pedestrian routes are colorcoded based on travel time. Areas without color represent problem locations.
Journal Article Review (Notes), PLAN 626: Advanced GIS in Landscape Architecture and Urban Planning, Submitted By – Avinash Shrivastava Page 2
Applying GIS Technology to Improve Transit Accessibility - Lawrence Marcus, Jose Rodaniel Cruz
SLIDE 7 On a City-wide scale, one can see how this type of analysis produces a more real-world view of actual walk sheds available to access transit service. Areas outside blue shaded areas are those beyond 1/4 mile access to transit service. These walk sheds were then cross-referenced with Census data to estimate population inaccessible to transit. The result was, of the total population 47,388 residents, 23 percent (11,314) cannot access transit without a car.
SLIDE 8 OBJECTIVE 2: Increase the Number of Residents within a 10Minute Travel Time to a Metrorail Station, using the Local Bus Service •
To evaluate access to the Rockville Metrorail station, the GIS model was used to integrate the results of Objective 1 with transit performance.
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Transit lines are color-coded, reflecting the travel time to the Rockville Metrorail station.
SLIDE 9 OBJECTIVE 3: Maximize the Transit Frequency of Service Finally, the quality of transit service in Rockville was assessed using data on the frequency of transit service and the population/employment base. This graphic shows the results of this analysis, including overlapping service.
Journal Article Review (Notes), PLAN 626: Advanced GIS in Landscape Architecture and Urban Planning, Submitted By – Avinash Shrivastava Page 3
Applying GIS Technology to Improve Transit Accessibility - Lawrence Marcus, Jose Rodaniel Cruz
SLIDE 10 City evaluated the findings of this study, recommending the following modifications to the transit system, depending on the central issue in a given area: (a) Modify the route(s), (b) Add or change bus stop locations, (c) Add shuttle service. And I would like to use the same approach for my professional paper topic i.e. facilitating trips to key destinations (B-CS area), by re-routing the Texas A & M University buses.
Journal Article Review (Notes), PLAN 626: Advanced GIS in Landscape Architecture and Urban Planning, Submitted By – Avinash Shrivastava Page 4