Tag Archives: TIGER

Fixing Megabridges in TIGER

For some reason … for whatever reason … the TIGER data has some entire ways marked as being bridges.  When examined, only a small portion of them is a bridge. I’ve been fixing them as I happen to notice them, but today I felt like seeking them out. I thought about writing a fancy program to parse the New York State section (as found on <a href=”http://downloads.cloudmade.com”>Cloudmade downloads</a>) to look for bridges.

I was reminded, instead, that the XAPI can do its own cut of OSM data. It’s fairly straightforward to do. The full XAPI documentation is in the wiki. All I did was fire up JOSM, and make a few bounding boxes around New York State. I did three: one for the southern tier, one for the adirondacks, and one for the NYC metro area. The first one’s URL looks like this: http://www.informationfreeway.org/api/0.6/map/way[bridge=yes][bbox=-79.6289,41.9677,-73.3667,43.3731]
I fetched it with wget -O southern.osm ‘URL’.  It’s only five megabytes and loads into JOSM easily.

Once loaded into JOSM, you can see the very long bridges. They stick out like a sore thumb. I pick one, zoom in to fill the screen with it. I have the Terraserver Ortho WMS layer turned on, so I can see where the bridge really should be. Two selects of nodes, split the way, and delete the bridge=yes tag. I’ll have New York State fixed up in about an hour’s worth of editing (not counting the time to write this blog entry).