Severn Bore – a spectacular natural phenomena

Over the next few weeks there are some 5* Bores coming up….ok – so that could be read more than one way. Let me explain! The Severn Bore is far from boring – in fact it is quite amazing! The bore is a large surge wave that can be seen in the estuary of the River Severn, where the tidal range is the second highest in the world – as much as 15 metres. For a bore to occur you need the river estuary and the tidal conditions to be just right. The Severn Estuary is shaped in such a way that the water is funnelled into an increasingly narrow channel as the tide rises, which leads to the formation of a large wave. The river follows a course past Avonmouth where it is approximately 5 miles wide, then past Beachley and Aust, then Lydney and Sharpness where it is approximately 1 mile wide. Ever narrowing, by the time the river reaches Minsterworth it is less than a hundred yards across. As well as the width decreasing rapidly, the depth of the river also changes rapidly and so a funnel shape is formed. The incoming tide travels up the estuary, being funnelled up an ever decreasing channel, so forming a surge wave – a bore.

Surfing the bore has become quite a sport with dozens of surfers competing to record the longest ride. Distance records have been broken on numerous occasions with the Guinness World Record holder, Steve King, recording a ride of 9.25 miles! With the bore reaching speeds of approx 10mph that’s quite a long ride! Canoeists and windsurfers also love to take a ride on the bore. The huge difference between surfing the bore and surfing at sea is that if you miss the bore you’ve got a long time to wait until the next one…ohhh…and don’t forget to have someone ready to meet you at the other end. It’s a walk back to the car with a board!

For great information about where and when to see the bore visit http://buff.ly/15Qhc1O The weekend of 20th February at the end of half term is due for two top rated 5* bores.

 

Surfing down a River

Surfing down a River

Have you seen one of Britain’s spectacular natural phenomena, the Severn Bore? It is a large surge wave that occurs in the estuary of the River Severn, where the tidal range can be as much as 15 metres. The estuary is shaped in such a way that the water is funnelled into an increasingly narrow channel as the tide rises, thus forming a large wave. As the width of the river rapidly decreases, so does its depth, thus forming a funnel shape. As the incoming tide travels up the estuary it is squeezed into an ever decreasing channel and the surge wave, or bore, is formed. The wave travels upstream for roughly 22 miles until it reaches Gloucester.

The Severn bore has become very popular with surfers, with the largest biggest 4 and 5 star bores occuring in conjunction with large spring and autumn tides. The bore is best surfed on a nine to ten foot longboard – the extra buoyancy and length are necessary when attempting to surf a tidal wave. If surfing is not for you, the bore also attracts a lot of spectators, eager to watch the spectacle as the bore travels past.

For Severn bore times and more information visit http://bit.ly/severnbore

Severn Bore

Photo credit: cc-by-sa/2.0 – Surfing the Severn bore by Jim Nicholls geograph.co.uk/p/379254