So I'm pretty new to GIS, and I'm working on a mapping project using data for Vancouver, Canada. I want to combine OpenStreetMap data along with data provided by the City of Vancouver. But the City data don't line up with the OSM data when I map them in QGIS.
Following the advice of an answer to Projected maps should but do not overlap in ArcMap?, I checked the two data sources against a third (a map of the world). The OSM data is right -- British Columbia is in the right spot -- but the City data puts Vancouver in the south of France.
My data sources are:
- Bikeways and libraries from the City of Vancouver. (Both are SHP files.) These are the data that don't align with the others.
- A map of British Columbia from Open Street Map. I put the data into a database using osm2pgsql.
- A world map that's part of the Open Street Style project.
Projections:
- The City data are projected in UTM zone10, NAD83 (CSRS). I've selected this in QGIS's Layer Properties screen for those layers. Projection string:
+proj=utm +zone=5 +ellps=GRS80 +datum=NAD83 +units=m +no_defs
- The OSM maps are in Mercator projection. QGIS has many Mercator choices, and I wasn't sure which one to use, so I guessed "Popular Visualization CRS / Mercator".
+proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs
- For the world map, Quantum GIS loaded the projection from the .prj file. That's
+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +over +no_defs
Projected maps should but do not overlap in ArcMap? talks about zone problems. That sounds like what I might be experienceing. So I tried changing the libraries from UTM zone 10N to other zones (15N and 60N) but nothing changed.
Does anyone have suggestions for what to try next?
+proj=utm +zone=10
and not+zone=5
because I would think zone 5 is very close to somewhere in the UK (starts with a G...) and that is why your data is coming up in France