In Canada we are currently importing a lot of data from government sources, GeoBase and CanVec, but one of the initial conditions has always been to preserve what has already been imported. This has caused some additional work in that we now have to combine the two sources, and some people have felt that erasing their initial work and asking for a complete import from the government sources is preferred,but it is proving to be effective. Also as you are importing roads, some of which may have changed or not even exist within the government sources, you also have the opportunity to add Points of Interest (POI) that are never going to be included within the government data.

Within the wiki about importing from other sources there is the instruction to respect the data that others have already contributed. In the Netherlands, and I believe also in the USA, permission was asked prior to deleting any user contributed data. In Canada we never asked and instead just respected the data that was already there and instead just added what was not already there.

There is already an ongoing effort to import the data from the Canadian government with GeoBase, which I believe is covered under the same license. We are currently importing the road data and there is an effort to load the Canvec data set afterwards. For more information please refer to the ongoing discussions on the http://lists.openstreetmap.org/pipermail/talk-ca/ mailing list and also on the wiki at http://wiki.openstreetmap.org/wiki/WikiProject_Canada and particularly the wiki dealing with the GeoBase import at http://wiki.openstreetmap.org/wiki/GeoBase_Import. If you want to help please contact the people on the talk-ca mailing list. The progress is very nice and we are getting the map of Canada looking a lot better.

There have been some discussions on the talk-ca list http://lists.openstreetmap.org/pipermail/talk-ca/, and the talk-us list as well, about it so it is a known issue. The conclusion that I believe they came to was that the GeoBase border was probably the most accurate and should be seen as the one to keep. Although the border between Canada and the US is nominally at the 49th parallel in the area there are actually markers that are used as reference points and they are not always as exact as they could be. And since there is really no way to correct unintended errors that occurred when they were marked the border does vary slightly from the intended location. Over time there is going to have to be an effort to clean up the border to ensure that there is really only one marked. Also the border for Alberta should actually be the international border as well.

For more information look at the thread started with http://lists.openstreetmap.org/pipermail/talk-ca/2009-March/000910.html and going well into April.

Welcome to the project.

The main map is updated once a week, I believe on Tuesday night/Wednesday, so you are not going to see it there until then. If you look at the same area using the Potlatch editor then you should see the changes.

Have Fun.

Richard
rtdg

Aah, that is very true. Unfortunately while Potlatch is easy to start with you also miss a great deal of the potential if you do not read the instructions and other mapping guidelines. It is possible to do a great deal with either Potlatch or JOSM and most of that is only after you are aware of the potential of the editors. Another thought is to look at some of the map of the week and see what others have added to see what you can do as well. Most people are very willing to show you how they did something and to tell you where they found the feature.
Richard Degelder
rtdg

If you check the map the changes will not appear until about Wednesday since that is when they are accumulated and the map is updated. If, on the other hand, you go back to edit the same area with the Potlatch editor, which is what I am assuming you used although it is also true for the JOSM editor, the new additions should be there. Basically for the chnages to appear on the main map wait until Wednesday or Thursday and they should be there.

With Potlatch it is easy to do. Highlight the trace and then highlight the point, in this case at the intersection with York Mills Road, where you want to separate the two streets. Then go to the bottom left corner of the Potlatch screen where you see the scissor. Clicking on this icon will separate the two streets and allow you to rename the incorrect one.

It is also easily done with JOSM. When you have highlighted the street and the point go into the menu items at the top and look for tools. One of the drop down menu items is to "Separate Way" and clicking on this will do the same thing.

A quick and dirty method, while in Potlatch, I use to eliminate one or more points is to click on the last point in a way and then, when it is highlighted as if to extend the way, to hit the "Backspace" key on the computer. This causes the point to be removed and allows you to create a new point or to either continue to remove points or to leave it. This also works for undesired POI that I want to eliminate.

This is the easiest method to get what you want with Potlatch. It also works the same with JOSM. When attempting to break up a way, or in this case a street, at a point that it shares with another way then it is necessary to first click on the way itself and then, while also depressing the "Shift" key and then click on the node that you want to break up the way at. While pressing the "Shift" key you can collect a number of nodes and/or ways while not using the "Shift" key only remembers the last way or node you used. One the way is separated you can edit the data for the incorrect street easily.

The map is, I believe, updated on Thursdays so the changes should appear on or after Thursday. There is, I also believe, a way to speed up the changes but at this point I forget the process.