It has now been a little over 3 years since Natural Resources Canada released CanVec, a national coast to coast to coast spatial dataset at 1:50,000 or better nominal scale. In the interverning time there have been several updates, we now sit at Edition 6, and there are scheduled updates every 6 months, indefinitely.
Canvec replaces the National Topographic Database (NTDB) which was both expensive, ~$240 per NTS tile if memory serves, and definitely not libre. With the NTDB we had to pay royalties for every map that went to another party, even if we gave it away. The royalty was reasonable, on the order of 25 cents each, but we had to pay in advance, in $5,000 chunks, with a minimum of $8,000.
Canvec is a well modelled internally consistent dataset of good quality, better than the NTDB, and it's FREE, both libre and gratis. What puzzles me, greatly, is the virtual silence online* about this fantastic resource. There is little chatter about Canvec. Perhaps this scale of data just not that relevant south of 60°N and you're using something different. Perhaps the naming conventions are so opaque that people just can't drum up the energy to figuring out what's what.
Where are the resources and tools to make using this stuff easier (or even possible)?
Answer
Where are the resources and tools to make using this stuff easier (or even possible)?
Geogratis from Natural Resources Canada now has a web based data extraction tool @ http://geogratis.gc.ca/site/eng/extraction
It's really easy, I tried it the other day.
First you can just select your Clipping Area by either:
- Current map extent
- Predefined clipping area
- NTS sheets
- drainage areas
- landsat footprints
- Custom Clipping Area
- Draw a rectangle
- Draw a polygon
- Enter coordinates (two corner coords in DD)
Once you've got your area of interest, you can Select the Data but... You won't be able to select CanVec or "Topographic Data" until you are zoomed in close enough (it's scale based and greyed out until you zoom in).
If that limitation becomes a problem, they have a neatly (finally) organized site of the canvec themes for each province and theme at http://geogratis.gc.ca/site/eng/download available as either FileGDB (don't know what version, but I couldn't open them with gdal) or GML.
But the FileGDB you get from the data extraction tool does work in gdal - they are >= version 10 FileGDBs.
There's a new QGIS plugin called NTS Data Download/MapSheetDownload that should help too. Now I can retire some of my scripts.
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