I am an environmental engineer and the aim of my QGIS 2.0 project is to visualize the results of a sewage water system inspection. In a first step I included the hoppers from a csv file and added a google streets layer. enter image description here

As you can see in the picture the hoppers don't overlay with the base map. I compared to the coordinate calculation of a mountain climber page (http://www.deine-berge.de/Rechner/Koordinaten/Sandersdorf,-06792-Sandersdorf-Brehna,-Deutschland), which confirms the on the fly crs transformation of qgis 2.0.

So the coordinates of the hoppers are may wrong. However it is the only csv data I have and in the GIS system of our branch office it fits to the base map.

Is there a possibility to move the base map by hand in order to achieve an overlaying?

For my purpose I don't need an exact fitting, but a difference of 500 m is too much.

  • How did you get a google streets basemap into QGIS (import raster or WMS)? – artwork21 Mar 6 '14 at 13:40
  • I used the Open layers plugin – user27662 Mar 6 '14 at 14:30
  • QGIS has a little bit of trouble with EPSG 3857. What does your .prj file for the google streets layer say? hub.qgis.org/issues/7368 – midfield99 Mar 6 '14 at 15:24
  • Since I used the open layers plugin to add the streets layer I have no .prj file for it – user27662 Mar 10 '14 at 7:07

Here are your options:

  1. You cannot move or edit the Google street map since it is coming in as a WMS.
  2. You should use another basemap service (e.g. OpenStreetMap layer) and see if your data aligns any better. If not, then you have a projection issue on your point data (I'm not sure what coordinate values you are plotting within your csv (x/y or lng/lat)).
  3. If all else fails and accuracy is not that critical and you are just trying to show estimated locations of your point data you could always start an edit session on that layer and move the points one by one or select all an move.
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  • Hey artwork21, Thank you for your answer. My hopper coordinates are x/y coordinates (Gauss Krüger). Could you explain me point number 3 (sorry I am really a newbie)? How can I select all points and move them? – user27662 Mar 10 '14 at 6:59
  • Since my boss needed a quick, pragmatic solution I decided to manipulate the coordinates. Now the hoppers fit to base map coarsely. – user27662 Mar 10 '14 at 8:39
  • @user27662, to select multiple features use the "Select Features by Rectangle or Select Features by Polygon" tool. Once you have multiple features selected you can use the "Move Features" tool located on the Edit toolbar. – artwork21 Mar 11 '14 at 22:37
  • Thank you for the hint. I just tried it. I can select the hoppers but the "move features tool" is disabled. I think it' s due to the csv format – user27662 Mar 12 '14 at 12:48
  • @user27662, the layer needs to be a shapefile or someother geospatial layer. Start an edit session on the layer, make your selection, and then you should be able to use the move tool. – artwork21 Mar 12 '14 at 17:38

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