I recently participated in a Missing Maps mapathon for the first time. The meetup group Maptime Seattle, a local chapter of an international geospatial group focused on teaching all things maps, had chosen their monthly topic to be Missing Maps. Missing Maps is a collaboration project between Humanitarian OpenStreetMap Team, American Red Cross, British Red Cross, and Doctors without Borders. The group’s main goal is to generate maps and data to aid in crises response by mapping vulnerable places in the developing world. As part of this goal, the Red Cross hosts mapathons where volunteers digitize buildings and roads on the OSM platform. These data are added to OSM and are later groundtruthed by teams of local volunteers. It is this second part of Missing Maps that SpatialDev’s POSM project is focused.

For the mapathon, the group focused on mapping an area in West Swaziland to assist with malaria eradication efforts. After a quick overview of the mapping process given by the two Red Cross / OSM Seattle volunteers leading the mapathon, the digitizing began! The group focused on digitizing buildings. I choose an area with a higher density of buildings compared to most of the project area. Generally there were multiple buildings in what seemed to be a single property or lot. The only difficult part of the process was trying to discern if an area was a building or not. This led to a discussion with some of the other mappers about how large an area should be to be considered a building. It was interesting because it showed how people’s own biases affect the maps and data they create, an aspect of mapping that is often overlooked as data is so often viewed as strictly scientific, void of any personal bias.

In addition to the rare opportunity to help with a project happening across the world, the meetup provided a great space to talk with other people who use or are learning to use OpenStreetMap. Thank you to both Maptime Seattle and Missing Maps for hosting a great mapathon!