<html><head></head><body>Hi Edward,<br>That is exactly the reason. Local authority jurisdiction extends to low water (MLW or MLWS), the coastline is defined as high water MHW or MHWS).<br>In England and Wales I know it's defined as MLWS but I have a niggling memory of the legal definition being subtly different in Scotland.<br><br>I can't recall seeing LAT begging used outside of a shipping context before, but I will be sure to look into your link, thanks!<br><br>Regards, Colin<br><br><br><div class="gmail_quote">On 19 August 2021 00:11:01 CEST, Edward Bainton <bainton.ete@gmail.com> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div dir="ltr">Hi all<div><br></div><div>I've just seen that the boundary of Comhairle nan Eilean Sar ("Council of the Western Isles"?) is a very odd shape:</div><div><a href="https://www.openstreetmap.org/?mlat=57.5057&mlon=-7.3120#map=13/57.5056/-7.3121&layers=N">https://www.openstreetmap.org/?mlat=57.5057&mlon=-7.3120#map=13/57.5056/-7.3121&layers=N</a></div><div><br></div><div>Is there a simple explanation? Is the local authority boundary line Mean Low Water Springs, perhaps, and the OSM coastline is MHWS?</div><div><br></div><div>(I don't know if it's relevant, but <a href="https://en.wikipedia.org/wiki/Udal_law">Udal law</a> in Orkney and Shetland law has lowest astronomical tide as the limit of land ownership. Perhaps there's a Norse influence here, too? But I'm guessing probably more prosaic.)</div><div><br></div><div>Thanks</div><div><br></div><div><br></div></div>
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