Public Transportation at Chennai - OpenStreetMap


As we already discussed in our riot room (some of you who are not active on riot-matrix, might have missed), the GTFS (General Transit Feed Specification) data for Chennai city is either incomplete or not updated after 2010. Among several hundred routes, there are only 7 routes that are listed in the GTFS data created back in 2010 by someone.

On doing a sample query for bus stops at Chennai in OpenStreetMap gives atleast 640 bus stops. I propose we shall do the following.

  1. Verify in our area whether the bus-stop details are proper, if not update them.
  2. Create route information (at this moment I don’t have much knowledge on this).
  3. Using these information from OSM, we can generate a updated GTFS data and publish them for usage with other Free Software services like Transportr.

Similarly, If I am not wrong it is also easier to do the same for Chennai Metro Rail. Interested people can share your knowledge, how-to’s and questions here, so that we shall help each other in building this commons.

Chennai Mapping

Yes making GTFS through community effort, makes it resiliently open and socially updatable. Just like any other community projects - as in Wikimedia and OSM, contribution here is not going to be one way. i.e, contribute and maintain it. Anybody who is interested shall take up the following process :

  • if you are interested first prepare mentally to contribute for your local transport region
  • come together and learn about GTFS, and observe what are the kind of data needed for making the contribution complete.
  • use HOT OSM’s map managing service, to initiate a mapping party by marking and caking the region (here routes and roads, highways) before field survey.
  • use location - field survey (nowadays mobile phones have integrated GPS, and geo logging apps. like OSM&)
  • start in a holiday, take a bicycle, attach your phone to it, follow one route (eg. 12E) and mark the stops while enabling gps track logging. (this attempt can be achieved collaboratively at field level. Either 2 or more of your friends can split up the route - think relay game, practically follow the bus. No need to hurry, buses will be coming with defined frequency in urban areas. Friends can also use a motorized bike rider and mapper strategy - but fuel will be spent remember. !)

  • connect the phone and clean the logged location - points of interest. Use JOSM or iD, and mark the locations with public transport tags with collected details. This where armchair peer group will shine.

Me and Niranjan have tried this last year for Vellore - and learned it would be more effective as a community effort.

  • Learn the validation process.
  • Collect the data from OSM using its API or services or GIS tools locally, and try to extract necessary details that matches GTFS specfication. Nowadays there are FOSS tools which could extract data, process them, analyze them…etc.