[Tagging] Canal banks

[Christoph Hormann]

On Monday 03 February 2014, Dave F. wrote:
>
> When mapping canals I've always drawn a closed polygon & used the tag
> waterway=riverbank when I've wanted to give them width. This is as
> per the wiki recommendation:
> http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dcanal.
>
> A user has recently amended them all to natural=water & water=canal.
> Is there a specific reason for this? Does it correct any problems or
> give any advantages for rendering etc?

The advantage is that you can determine it is a canal from the polygon 
alone.  With waterway=riverbank you have to find the corresponding 
centerline first (assuming it exists).

-- 
Christoph Hormann
http://www.imagico.de/