Google Fusion tables are an excellent way to map data. They give you a means to create intensity maps showing any statistics you care to mention that vary regionally, such as crime, unemployment or age. Google Maps recognises a type of file called a KML file. To Google KML files are just sets of coordinates that make up a shape, but to us they can mark out London from the rest of the UK, wards in Bristol or the entire world’s borders.
Simon Rogers (a City visiting lecturer) has a handy bank of KML files, but if you can’t find the perfect one that suits your needs the answer might be to create it yourself. This post builds on Dane Watkins’s post here. For this example, we’re going to create a KML file of wards in Bristol (you’ll need a Google account for this).
Step 1: Open up your map
Go to Google Maps and select “My Places”, then “Create Map”
Step 2: Find your wards
A list of the City of Bristol’s wards can be found here.
Step 3: Find detailed maps of your ward boundaries
Bristol City Council published a detailed ward profile of every ward in 2008. If you search for “Ashley ward profile”, you will come across a PDF of Ashley ward containing a reasonable map of its boundaries.
Step 4: Draw your ward on to the map
This can be fiddly, particularly at first when it feels like starting a jigsaw. Locate a place to start on Google Maps that corresponds with the border of the ward boundary, such as St Andrews park here in Bristol. Click “Draw Shape”, then map out the boundary. Cross-reference your shape with the existing ward map, but you don’t have to be precise to the nth degree. Connect your last line back to the first dot to complete the shape and name it after your ward.
Step 5: Repeat
I won’t pretend this doesn’t take time. For all I know, there is a Bristol ward KML file out there already and I just didn’t find it. However, once you’ve got your KML file, you can use it as many times as you like. For a journalist covering a particular city or region, it has the potential to be incredibly useful.
Step 6: Export your finished map as a KML file
You now have your completed map. Make sure all the wards are in alphabetical order, this will save time later. Click “Done” then “KML” should appear.
Step 7: Open a Google Fusion table.
Open a new Fusion table in Google Drive. Select a file from this computer and then pick your KML file, which should be in your downloads folder. Click “Next”, then “Finish”.
You now have a Fusion map that you can use to map all sorts of data for a particular area. I’ll use my Bristol one in the next few weeks to play around with.
If there’s a faster way of doing this, please get me touch and let me know.
UPDATE: This link from Paul Bradshaw shows a more accurate way to build a council ward map using scraping. That might mean what I just showed you how to do is a tad less relevant than before, but this is a learning process for both you and me. I don’t pretend to have all the answers…