Map geeks in the bowels of City Hall

Following past discussions with staff at Southwark Council and the Greater London Authority, I helped organise a technical  workshop in City Hall this weekend. We brought some key OpenStreetMap geeks together with some keen potential early adopters from the GLA, Southwark and Brent to talk open maps and hack on data & tools.

Harry Wood will post a useful rundown of some of the stuff people hacked on over the two days.

The only practical thing I did was to work with Rob Scott (OSM) and Scott Day (Southwark Council) to try and extract buildings from the open Ordnance Survey maps so we could merge them into OpenStreetMap without having to manually trace every single one (yawn). For the nerds, I’ve written up our initial results on the wiki.

Talking with Scott, it was clear that Southwark probably have a lot of data we could benefit from, and that they would really like to use OpenStreetMap in lots of places where they don’t need the pinpoint accuracy for road shapes, gardens, etc. that they get with commercial products like UK Map and Ordnance Survey’s Mastermap.

Alisdair Maclean from Brent brought the whole road network on a USB stick. Robert did a quick visual analysis of differences with OSM data using his “musical chairs” app, and Grant overlayed the two sets of data to spot roads he had missed over the years. Again, I hope Alisdair really benefited from the opportunity to chat.

The trick is really just to keep experimenting and helping government people to try things out. Expecting local authorities to just come and use OSM without any decent documentation or personal contact is… well, it won’t happen. Without those relationships, open data initiatives like the London Datastore could just end up dumping data on the public without benefiting from our capacity to correct and improve upon that data.