Thursday, February 19, 2009

Constructing Free Maps Through Household Surveys

Maps in most of Africa are hard to come by and it is even worse to find free GIS data. A wiki style project - - emerged a few years back to map the world free for all, but until recently it has failed to make major impact in Africa. Things are now progressing rapidly as you will see in various gif-animations and other material on their website.

As part of the MICS4 pilot in Mombasa, Kenya, a GPS unit was left on at all times during field monitoring. This was done to test how feasible it would be to upload the collected tracks and then edit data into a road network in and around Mombasa. You may follow the progress here.

Please note that Mombasa was almost unmapped before this excercise.

You may be aware that Google offers pretty much the same service on online maps - however, these maps are copyrighted and are not flexible in use. For comparison here is Google's map of Mombasa and surroundings.

Google has an office in Nairobi, so their coverage is very good here, unlike in the rest of Africa.

The test was done for a number of reasons:

  • Many survey coordinators have been asking for advice on how to utilise GPS units further. Handing units to field team supervisors to mark cluster locations has long been used to attach data to geographic locations, but why not keep the units on at all times (using the cigarette lighter)? This way you can track the location of vehicles at all times (checking mileage and fuel consumption) and create an almost full coverage map of the survey location.
  • Another idea is to equip listing teams with units and have all households marked and numbered on maps, thus making location much easier for interviewers.
  • Further, we could ask all interviewers to mark all households visited, making it very unattractive to take a day off filling questionnaires under a tree...
  • Finally, it seems very unproductive to leave field team drivers without anything to do for entire days.

Should you be interested in participating in bigger pilots, in discussion on how to best employ GPS units, or in any related matter, feel free to contact Bo Pedersen, ESARO MICS Coordinator, at



  1. Update: The mapping in Mombasa went very well, but also with limited data. A larger pilot data collection was undertaken in March 2009 in Eastern Region of Kenya. This time four cars were equipped with GPS receiver and were in the field for one week in connection with a follow-up to the Eastern Province MICS of 2008. You can track progress on

  2. I am very happy about the massive amount of feedback I have received on the above... ZERO...

    I am pushing forward though (because of the potential seen in the tests) and have convinced Swaziland and Somalia to utilise their GPS units further in their 2010 MICS. A ToR is drafted for the development and delivery of training for drivers/a.o. and for development of further applications.

    Will keep all of you zero people posted...