On 25/01/16 14:31, Ian Sergeant wrote:
On 25 January 2016 at 14:48, Ross <i...@4x4falcon.com> wrote
How do you know it is the physical feature?
Just because it follows approximately the feature does not mean it is. When
originally gazetted the physical feature may have been located differently
(roads, railways realigned, rivers making new paths) Don't automatically
assume that the feature is still in the same place without looking at the
imagery or physical survey. Don't assume that the boundary changes to the new
position of the road, etc.
There are numerous ways you can 'know' something. Legislation
(including regulations, court judgement) is often the primary thing
involved here. I'm not calling on people to guess, but we should bear
in mind that OSM is an evolution, and we have often used these
features in evolving the map until we locate or have free access to a
definitive source.
So you check each and every time for a source that shows the boundary
you are working on is the physical feature and then provide the source
in a tag?
As you suggest most people will just guess and a lot of the time it may
be so but it still causes issues with later changes and corrupting the
original data (such as the NSW reserves boundaries).
And the guess does not get fixed there are many locations where roads
are still on admin boundaries but the boundary is no long there (changes
to boundaries) or the road has moved but nobody comes back to correct it.
But the border has not changed the river might have but there is no change to
the border from when it was first surveyed/gazetted. The border is the line as
when gazetted, not as where the riverbank is now.
I think you're wrong. The border has been defined by High Court
Judgement as including accretions and erosion. Including landslip
such as in the Ward case.
Of course, where the river has fundamentally changed course, the
original course remains the boundary. But gradual erosion actually
changes the border.
Ian.
But not in all cases as your previous post suggested and the location I
pointed out shows.
Cheers
Ross
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