[Talk-GB] Coastline and tidal rivers

[Mike Evans]

On Tue, 28 Aug 2018 11:09:47 +0000
"David Groom" <reviews at pacific-rim.net> wrote:

> There is no consensus.
> 
> Personally I'm not in favour of the view that any body of water which is 
> tidal should be bounded by a way tagged as coastline.
> 
> Reasons for this
> 
> 1) Ask any one who lives in say central London "do you live on the 
> coast" or do you live beside a river", most would I'm sure say beside a 
> river, so surely our data should reflect that.  I think this probably is 
> what you mean by "seems more natural"
Well if they're in Central London then it is an estuary at that point so they'd be incorrect. Hence the expression "estuary English", and not "river English".
To quote Wikpedia "The district of Teddington a few miles south-west of London's centre marks the boundary between the tidal and non-tidal parts of the Thames". 

Perhaps "A History of the Foreshore and the Law Relating Thereto",  published 1888 would be a useful reference.
https://archive.org/details/ahistoryforesho00hallgoog


> 
> 2)  In part because the converse is not true, we bound large non tidal 
> water areas as coastline
Examples?

> 
> 3) If knowledge that a body of water is tidal is important it can be 
> tagged "tidal = yes"
But then the decision has to made as to where to draw the line and tag one side as "tidal = yes" and the other side not tagged but assumed to, in fact, be tidal. This just introduces an extra arbitrary boundary the inner end of which again becomes non-tidal.

The American Submerged Lands Act of 1953 does appear to define the line at which the coastline extends into estuaries etc., but this does not apply to the UK.  That act seems to been precipitated as a result of disputes over oil drilling rights.

Mike