12 mile limit baseline

[nemodreams]

12 mile limit - definition of boundary ?

This is a quote from Wiki - on the rules for the Baseline of the 12 mile Uk limit.

Baseline
Main article: Baseline (sea)

quote ...
http://https://en.wikipedia.org/wiki/Territorial_waters

Normally, the baseline from which the territorial sea is measured is the low-water line along the coast as marked on large-scale charts officially recognized by the coastal state. This is either the low-water mark closest to the shore, or alternatively it may be an unlimited distance from permanently exposed land, provided that some portion of elevations exposed at low tide but covered at high tide (like mud flats) is within 12 nautical miles (22 km; 14 mi) of permanently exposed land. Straight baselines can alternatively be defined connecting fringing islands along a coast, across the mouths of rivers, or with certain restrictions across the mouths of bays. In this case, a bay is defined as "a well-marked indentation whose penetration is in such proportion to the width of its mouth as to contain land-locked waters and constitute more than a mere curvature of the coast. An indentation shall not, however, be regarded as a bay unless its area is as large as, or larger than, that of the semi-circle whose diameter is a line drawn across the mouth of that indentation". The baseline across the bay must also be no more than 24 nautical miles (44 km; 28 mi) in length.

Not the simplest thing to understand.

My real question is though - why is the 12 mile limit not marked on Uk sea charts ?
Or - why is the 'Baseline' not marked.

Considering many are insured UK coastal waters it could be very important !

 

[AntarcticPilot]

Well, charts are not primarily produced fro the benefit of yachts. They are mainly for commercial shipping and naval vessels, and in both cases, the 12 mile limit isn't of much interest, unless you're a US Naval vessel passing near the Paracel Islands!

Actually, it's easy enough to be sure of whether you are within territorial waters or not - if there is land within 12 miles, you are within the territorial waters of that land. The only exception is for enclosed waters like the Minch, Bristol Channel and the Firths of Scotland (where you may be more than 12 miles from land but still within territorial waters). Although the definition is complex, that's what it actually works out at. Because of the geometry, it will also tend to work out that the nearest land will be a headland more often than anything else.

I have been involved in determining the baseline for a British Overseas Territory. The political decisions are actually much harder than the geographic ones!

And unless you are deliberately setting out on a passage that will definitely take you beyond the 12 mile limit, I doubt anyone would worry. You can always claim stress of weather. I'm always surprised at the insurance industry worrying about it - in a well-found boat (and I'm sure most of us have such boats), my automatic instinct in the case of really nasty conditions would be to get away from land, as that's safer!

 

[nemodreams]

Thanks -

now I look at this again - in the light of what you say it seems clearer ( slightly )
Mine is coastal waters of Europe ( Nav & Gen ) so it is an issue to me - if I venture afield !

 

[Bru]

I had to go look cos I thought it was and the 12 mile limit is clearly marked on admiralty raster charts cos it's relevant to fishing

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