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Simple Cartographic Exercises Can Radically Alter the Real World

ByAmy NowogrodzkiNOVA NextNOVA Next

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The lifeblood of Nairobi’s transit network is a collection of colorful minibuses so unregulated that a map of the whole system didn’t exist until a year ago.

Most people in Nairobi rely on these buses, called matatus, to get around. Thanks to a team of researchers at MIT, Columbia, and the University of Nairobi, an online map of matatu routes has already caused changes in Nairobi. This map-building approach could address transportation issues in many other places, since “the majority of global cities have these informal transit systems,” said Sarah Williams, a professor of urban planning at MIT and project contributor.

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Matatus are informal networks of minibuses that shuttle people around Nairobi.

Nairobi is the second-fastest-growing city in Africa, forecast to grow 77% between 2010 and 2025, but the public transit system has slipped into a state of official neglect. Since 1997, the city’s population has nearly doubled to 3.5 million, but the government has planned no new routes. Into this breach stepped the matatu drivers, and an unruly network of new routes sprang up around the previously planned routes to meet the new demand.

Matatus, often brightly painted with funny, crude, or religious slogans, are a cultural icon, a source of frustration, and “a topic of constant conversation,” Williams said. They usually seat one to two dozen. Project contributor and Columbia University associate research scholar Jacqueline Klopp recalls once leaving a party in Nairobi only to step into “a continuation of the party”—a matatu decked out with a disco ball, loud music, and dancing riders. But they also have a darker side: some matatus collude with pickpockets or are controlled by gangs.

Though everyone in Nairobi knows about matatus, the city government had been planning large projects, like a superhighway, without considering them. So the team of researchers decided to map the system. University of Nairobi students fanned out, carrying cell phones and GPS devices, and rode every matatu route in the city—all 130 of them.

They formatted the data to work with Google Maps and open-source software like Open Street Map and Open Trip Planner. Then Williams’ team at the MIT Civic Data Design Lab created the map, unveiled in February 2014.

The map is available on the project website,

Digital Matatus . Only 53% of Kenyans have internet access, according to August 2014 figures from the Communications Authority of Kenya, so although 3,000 people in Kenya have downloaded the map since February 2014, the University of Nairobi group has also informally distributed many paper copies.

Reactions to the map have been “really, really positive,” Klopp said. The matatu drivers “instantly wanted to use it to plan new routes,” Williams said, and “make a better system.” As soon as they saw the completed map, they realized that the northern section of the city was underserved and opened five new routes there.

The team also surveyed users and found that the map changed how some riders took routes. For example, some didn’t realize they could bypass the congested city center just by taking another matatu a few blocks from their usual route.

Even the government reacted positively, Williams said. “I was surprised by their reaction: they were really excited to see the map.” A national transport and safety authority looking at the map criticized an undesignated route, Klopp said, “and then there was a pause, and he said, ‘But you know what, though, if I was in that part of town, I would take that matatu.’”

Informal transit systems have been mapped in other cities, including Mexico City, Manila, and Dhaka. And Klopp has heard from people who want to replicate this kind of effort in Lagos, Cairo, and Katmandu.

Kuan Butts, a graduate researcher on the Dhaka mapping project, said mapping a transit system is important because it “increases economic mobility.” It’s much harder to reach areas with jobs or economic opportunities without a map. “In Dhaka,” he said, “people knew about other parts of the city but literally had no idea how to get to them.”

Maps are “supremely powerful at telling the story, showing the picture of what’s going on,” said Jeremy Crampton, a geographer at the University of Kentucky. “They are very enabling.” Williams would like her next step to be even more enabling: she wants to make an app for people in different cities to create these transit maps anywhere.