An Aerial Sensing Map-a-thon in Mongolia

Almost 60 percent of the population of the capital city of Mongolia, Ulaanbaatar, lives in “ger” areas – sprawling and mostly unplanned informal settlements on the periphery of the city – and these areas continue to grow as new migrants settle there. Ger area residents commonly lack basic services such as heat, water, electricity, and solid waste collection. Ger residents are accustomed to walking several kilometers to collect water from water kiosks, heating their homes by burning coal and wood, and building their own outhouses. As a result, ger areas contribute significantly to air and soil pollution in Ulaanbaatar.

While the City Municipality has commissioned a number of redevelopment projects to improve living conditions in the ger areas, it has encountered a significant challenge in the dearth of quality data on these neighborhoods. Existing maps lack important details, are out-of-date, and are often too low in resolution. While popular mapping platforms such as Google Maps and Bing Maps have adequate coverage of Ulaanbaatar’s more developed city center, they lack up-to-date, high resolution imagery of the city’s growing ger areas.

To fill this data gap, The Asia Foundation, in partnership with the City Municipality, turned to remote sensing technologies and open mapping techniques. Working with a local Mongolian land surveying group, the Foundation used unmanned aerial vehicles (UAVs) to collect over 100 square kilometers of high-resolution aerial imagery of ger districts. More than 12,000 images and corresponding geolocation data were acquired at 9.6 cm resolution. The raw images were processed and transformed into a dozen unique data sets using advanced geospatial analysis. Vector maps of road widths, road lengths, and permanent buildings, contour maps, 3D fly-throughs, and other data sets were generated and presented to the City Municipality. These geographic information system (GIS) data sets will help the city to make better-informed policy and budget decisions pertaining to ger area planning, urban service delivery, economic development, and a host of other concerns. On June 19, this collection of UAV imagery, vector and contour maps, and related datasets was officially delivered to the Ulaanbaatar City Municipality.

As a complement to the collection and analysis of the UAV imagery, the Foundation and the City Municipality also recruited members of the general public to help build a better map of Ulaanbaatar’s ger areas. Citizens of Ulaanbaatar know their neighborhoods best, and have a better lens on the changing landscape of the city. The Foundation posted the UAV imagery to the open mapping platform OpenStreetMap (OSM), a free, online map of the world, for the Mongolian community to map. Then, on June 20 and 21, the City Municipality and The Asia Foundation organized an OSM mapping competition, the “Map for UB Map-a-thon,” focused specifically on the ger areas of Ulaanbaatar.

Seventeen teams of over 50 Mongolian mappers participated in the Map-a-thon, including university students, mapping enthusiasts, and city government staff – experienced and new OSM mappers alike. In a single weekend, an astounding 20,000+ edits were made to OSM with the project’s UAV imagery as a base layer. Mappers recorded a range of ger area features, including homes and other buildings, ger plots (khashaas), construction sites, rivers, green spaces, and gullies. The city’s planning department will be able to reference these public maps to augment their own mapping data sets.

Three winning teams were awarded prizes based on criteria such as the number of features recorded or corrected, accuracy, and the completeness of edited locations. On June 22, the winners of the competition met with the capital city governor and mayor of Ulaanbaatar, Mr. Bat-Uul, to present their results and receive their awards. The mayor emphasized the importance of the UAV imagery project, and highlighted its potential to add value to the lands of ger area residents.

The UAV project and the community Map-a-thon are part of the Foundation’s longer-term commitment to improving urban governance in the ger areas. The City Municipality has embraced the benefits of remote sensing technologies for collecting geospatial data in ger areas, and is looking forward to incorporating the publicly collected OSM data in future policymaking.

Gantulga Ganbaatar is urban services project officer and Tirza Theunissen is deputy country representative for The Asia Foundation in Mongolia. Michelle Chang is ICT program manager for the Foundation’s Digital Media and Technology Program. They can be reached at [email protected], [email protected], and [email protected], respectively. The views and opinions expressed here are those of the authors, not those of The Asia Foundation.