What Is The Phenomenon Of The Severn Bore? I Oxford Open Learning
The Severn Bore

What Is The Phenomenon Of The Severn Bore?

The Severn Bore is a natural phenomenon that occurs on the River Severn in the United Kingdom. It is a tidal bore, which is a large and powerful wave that forms in the river because of the incoming tide from the nearby Atlantic Ocean

Of course, these bores aren’t present or noticeable in every river and there is a reason that the Severn bore exists and is such a spectacle. This is due to it having one of the highest tidal ranges in the world, with the difference between high and low tides often exceeding 14 meters (46 feet). This significant tidal range is a key factor in the formation of the Severn Bore.

Where It All Starts

As the Atlantic tide pushes water up the narrowing estuary of the River Severn, the water is funnelled into a progressively narrower channel. This narrowing of the estuary helps to amplify the incoming tide and creates the world-famous Severn bore, a powerful wave that travels upstream against the direction of the river flow. The wave can reach heights of up to two meters (6.6 feet) and travel at speeds of up to 21 kilometres per hour.

This would of course be quite a ride for anyone choosing to surf it, which people do! Colonel ‘Mad’ Jack Churchill was the first person documented to have surfed the bore, back in 1955. Surfers, being notorious thrill seekers, tend to target the biggest 3, 4, and 5 star bores, (with 5-star bores happening rarely, perhaps once a year).

When Best To See The Severn Bore

The Seven Bore is most pronounced during the spring and autumn months when the tidal range is at its highest. Friday 17th September to Saturday 19th October is the next, most densely packed period of 3- and 4-star bores. The size of the bore is influenced by various factors, including the alignment of the sun and moon, as well as atmospheric conditions, the amount of water flowing down the river and how well sourced the main drainage channels are.

The Seven Bore is a popular attraction for spectators, (underlining its phenomenon status), who gather along the banks of the Severn to watch as it travels upstream. You might even see me there as it’s very local to where I live.


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Image by Hywel Williams



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I am a practising HR consultant working with several start-ups on an ongoing and ad-hoc basis in the London and M4 area, and am a Chartered Member of the Chartered Institute of Personnel and Development or CIPD. I am the Director of thecareercafe.co.uk; thecareercafe.co.uk is a resource for start-ups and small business. It includes a blog containing career advice, small business advice articles, HR software reviews, and contains great resources such as HR Productivity Apps.

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