Comment by notavalleyman | Hacker News Reader

Comment by notavalleyman | Hacker News Reader

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Here's a licence issuing authority's faq section.

https://pla.co.uk/thames-foreshore-permits

>Why do I need consent?

> All the foreshore in the UK has an owner. Metal detecting, searching or digging is not a public right and as such it needs the permission of the landowner. The PLA and the Crown Estate are the largest landowners of Thames foreshore and jointly issue a permit, which is administered by the PLA, allowing all searching, metal detecting, ‘beachcombing’, scraping and digging.

Another section reads,

> The foreshore of the river Thames is a sensitive environment and London’s longest archaeological site, with finds dating back to 10,000 BCE. It is also the border to the UK’s biggest port and busiest inland waterway and must be protected and respected by all that use it.

> The Thames foreshore is a potentially hazardous environment which must be respected; it contains many dangers that may not always be immediately apparent. The Thames can rise and fall by over seven metres twice a day as the tide comes in and out. The current is fast and the water is cold.

>London’s longest archaeological site

The English have a bit of a history when it comes to looting historical artifacts. They would like to exercise some control over when they are found, I imagine.

The Elgin marbles are named for the Scottish noble who purloined them. It as much a British thing as it is an English one.

SEVEN METERS!? Wow!

The UK has some really big tides.

See the river Severn, whos estuary tidal range is 15 metres, and the second highest in the world.

https://en.wikipedia.org/wiki/Severn_Estuary

An image/map: https://en.wikipedia.org/wiki/File:M2_tidal_constituent.jpg

Basically the UK is in the way when a sizable chunk of the Atlantic wants to move north-east to follow the tides. The water squeezes into whatever openings it can find and creates really high tides in the process

I used to row in London on the Thames, and yeah, the tides are nuts. The river rises seven meters in the span of about 3-4 hours. (It takes about 7-8 hours to flow out.)

It's a largely artificial problem, too, with very small tidal effects originally. https://en.wikipedia.org/wiki/Embanking_of_the_tidal_Thames

The original marshlands were drained gradually for agriculture, and the land sank as it dried. The southeast of the island has been sinking relative to sea level for natural reasons as well.

From the link above:

> The Embanking of the tidal Thames is the historical process by which the lower River Thames, at one time a shallow waterway, perhaps five times broader than today, winding through malarious marshlands, has been transformed by human intervention into a deep, narrow tidal canal flowing between solid artificial walls, and restrained by these at high tide.

> With small beginnings in Roman Londinium, it was pursued more vigorously in the Middle Ages. Mostly it was achieved by farmers reclaiming marshland and building protective embankments or, in London, frontagers pushing out into the stream to get more riverfront property. Today, over 200 miles of walls line the river's banks from Teddington down to its mouth in the North Sea; they defend a tidal flood plain where 1.25 million people work and live. Much of present-day London is recovered marshland: considerable parts lie below high water mark.

For your further amusement - tide-proof "coastline railway in Brighton, England, that ran through the shallow coastal waters" :) And electric at that!

https://en.wikipedia.org/wiki/Brighton_and_Rottingdean_Seash...

" The single car used on the railway was a 45 by 22 ft (13.7 by 6.7 m) pier-like building which stood on four 23 ft (7.0 m)-long legs."

I have added this to-do to my time-travel list -- thanks!

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