Mapping informal transit routes in Bogotá

Bogotá’s urban footprint has expanded significantly since 1989, but its formal transit system, TransMilenio, has not. Residents of the newly urbanized areas have met their mobility needs through an informal network of van routes.

Until last summer, these newer, informal routes remained unmapped. Unlike users of TransMilenio or Boston’s MBTA, nobody could plan a trip on these van routes using Google Maps or even with a paper map. Riders simply had to know the routes to get where they were going or ask someone who did. Furthermore, the lack of transit data in these areas made it difficult for policymakers to plan for housing education, education, etc.

Vans wait at a bus stop in Bogotá. An informal transit system, they provide important connections to the city center and the TransMilenio Bus Rapid Transit system for residents in the new informal settlements on Bogotá’s periphery.

But all this changed when Eric Goldwyn, a Research Scholar at NYU’s Marron Institute and an Affiliated Faculty Fellow at NYU Shanghai, partnered with faculty and students at the University of Rosario to finally put these routes on the map. After testing a few different data collection apps in New York, the team decided to use Flocktracker for its ease of use, reliability, clean data outputs, and customer support. Working with Flocktracker’s developers, the team put together a customized tracker project and spent June through September riding the vans and collecting around thousands of GPS traces and information on nearly 200 van routes. This amount of data tested the limits of Flocktracker’s backend, but Eric was very thankful for the quick attention of Flocktracker’s expert developers, who quickly found a solution to the problem.

A group of University of Rosario students learn how to use Flocktracker to collect data on van routes.

Currently, Eric’s team is working to transform their Flocktracker data into GTFS, an open source structure for transit data that can be used in Google Maps and other software for analysis. He’s also trying to forge a relationship with the city and help them to get the insights they need out of this massive dataset, and he’s publishing an article on the relationship between informal transit, informal housing, and urban expansion. Next, he’s working on mapping transit systems for 200 cities around the world, including many with unmapped systems that will require extensive field data collection.

Left: a snapshot of all 600,000+ GPS traces that make up the van routes dataset. Right: raw data for one route, ZP 35.

For more on Eric’s data, check out this blog post from Flocktracker alumnus and data scientist Kuan Butts.