Wednesday, April 29, 2015

Humanitarian Open Street Map

The Nepal Earthquake has caused tremendous destruction. The Humanitarian OpenStreetMap Team (HOT) has been responding to these kinds of emergencies for several years now. They are recruiting volunteer mappers to improve maps in the affected areas to help disaster response. There is a small learning curve and the instructions are a bit vague in places, but anyone with basic computer skills can help out, including me. Here is some work I did yesterday in a valley east of Chautara, about 25-30 miles from Kathmandu.
I added buildings and paths to the map based on low resolution aerial photos from Bing.
To get an idea of how spotty the mapping is in this area, here is a map of a nearby quadrant. There are lots of houses and other buildings but many of them have no known road access. The dashed lines are listed as foot paths. There is probably motor vehicle access along these paths and along other routes that are not apparent from the aerial photos but the only known "road" on this map is the red line in the bottom right corner.
While mapping is still very incomplete in the area, you can see how much detail has been added to OpenStreetMap, when compared to Google Maps (right side below.)
Comparing a more urban area gives you a better picture of the detail that has been added to OpenStreetMap - this is near Tinchuli, just northeast of Kathmandu.

The rural area above was specified as a priority when I logged in. When you begin, they present you with a map showing which areas need work and where the priorities are. The areas are divided into grids and you can pick one or let them assign you a grid to work on. The unshaded areas are the ones that need work. This image is for a second pass-the first pass was mapped a few days ago.

In fact, mapping of Nepal has been ongoing for a couple of years now. The HOT anticipated this kind of emergency two years ago and had a mapping party - complete with a nice cake!.
Here is a quote from the project page, February, 2013.

Recently, several reports have warned that this spectacular nation is at high risks from earthquakes. According to Nepal Risk Reduction Consortium Secretariat, a mega-earthquake—which could occur at any time—is estimated to kill more than 100,000 in the Kathmandu Valley alone, injuring another 300,000 and displacing up to 1 million.
If anyone in the Washington D.C. area is interested there is a three day mapping summit there starting tomorrow (April 30th.) Hopefully someone makes them a nice cake - they deserve it!

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