I just realized that the Vaal river in South Africa, which has been mapped by different people has been mapped using Bing and CD:NGI imagery. This is not necessarily a problem in itself apart from the fact that in places the Bing imagery were taken during flooding and does not represent the normal flow of the river. There is thus some work required to differentiate this. In a previous diary entry people have suggested using a flood plain tag. It might be appropriate but only if it is a regular occurrence which I am not convinced it is. I will need to spend some time comparing exceptional flood event dates with the imagery dates and then make a decision on the frequency of occurrence to guide the choice in tag being used. Since I mapped a large part of the Vaal river, or at least it’s river banks, this diary entry is more of a note to self, to do the work at some stage.

The most used tag seems to be: flood_prone