UnlockedMaps: Visualizing Real-Time Accessibility of Urban Rail Transit Using a Web-Based Map
Ather Sharif, Aneesha Ramesh, Trung-Anh Nguyen, Luna Chen, Kent Richard Zeng, Lanqing Hou, Xuhai Xu · 2022 · Proceedings of the 24th International ACM SIGACCESS Conference on Computers and Accessibility (ASSETS '22) · doi:10.1145/3517428.3550397
Summary
This paper presents UnlockedMaps, an open-source web-based map that visualizes the real-time accessibility status of urban rail transit stations across six North American cities: New York, Chicago, Philadelphia, the San Francisco Bay Area, Seattle, and Toronto. The system addresses a critical gap in existing mapping tools — while platforms like Google Maps may indicate whether a station has elevators, none show whether those elevators are actually working at any given moment. For wheelchair users and others who depend on functioning elevators, an unexpected outage can render an otherwise accessible station completely unusable, potentially stranding commuters or forcing lengthy detours. UnlockedMaps collects data by scraping transit authority websites hourly for elevator outage information and quarterly for station data, covering 2,336 stations. Over 23 months of data collection, the system recorded over 1,061,375 elevator outage events. Stations are displayed on an OpenStreetMap-based interface with colour-coded markers indicating three statuses: accessible with functioning elevators (green), accessible but experiencing at least one elevator outage (orange), or not accessible (red). Users can filter stations by wheelchair accessibility, bike rack availability, parking availability, and transit line. Individual station pages show elevator outage history via a calendar view, enabling users to assess station reliability over time. The system also displays nearby accessible restaurants and restrooms using data from Yelp and Refuge Restrooms. All collected data is made publicly available via an API — making UnlockedMaps the first system to collect and openly share elevator outage data across multiple cities.
Key findings
Pilot user studies with 34 participants across five stakeholder groups — people with mobility disabilities, pregnant people, cyclists/stroller users/commuters with heavy equipment, disability advocacy group members, and civic hackers — showed consistently high ratings across all groups. Average scores on a 7-point Likert scale were strong for user-friendliness (M=6.2), feature helpfulness (M=6.1), usefulness for people in the same demographic (M=6.2), data helpfulness for developers (M=6.2), and data helpfulness for advocates (M=6.3), with low fatigue scores (M=2.7, where lower is better). Notably, there were no statistically significant differences between stakeholder groups on any measure, indicating the tool is equally valued across its diverse user base. The research demonstrates that elevator outage data, when collected systematically and made transparent, reveals patterns of infrastructure reliability that are otherwise invisible to commuters. The historical outage calendar allows users to make informed judgments about station reliability — a station with frequent outages may be avoided even when its elevator is currently working. The inclusion of accessible restaurants and restrooms near stations addresses the broader journey planning needs of disabled commuters, who must consider accessibility at every stage of a trip, not just the transit portion.
Relevance
UnlockedMaps addresses a fundamental equity issue in urban transportation: the gap between nominal accessibility (a station has an elevator) and functional accessibility (that elevator is actually working right now). This distinction is critical for accessibility practitioners and policymakers. The open-data approach is particularly significant — by making elevator outage data publicly available via an API, the project enables researchers, advocates, and civic hackers to analyze infrastructure reliability patterns, identify underserved communities, and build evidence for policy changes. Transit authorities typically publish current outages but not historical data, making it impossible for the public to assess station reliability over time. The broad stakeholder approach — including pregnant people, stroller users, and commuters with heavy equipment alongside wheelchair users — demonstrates that elevator accessibility benefits a much wider population than just people with permanent disabilities. This framing strengthens the case for infrastructure investment by showing the breadth of impact. For web developers and civic technologists, UnlockedMaps provides a replicable model for building open-source accessibility tools that collect, visualize, and share real-time infrastructure data.
Tags: transit accessibility · elevator outages · web-based maps · open data · wheelchair accessibility · mobility disabilities · urban accessibility · civic technology