The breaking news of the devastating Japanese earthquake and tsunami [which happened on 2011 March 11, magnitude 9] had a particularly awful ring to it for the many members of Wells Civic Society who were at its March meeting — because only 36 hours before the news, they had been hearing about a tsunami in Somerset.
If the audience had been asked to identify the worst natural disaster ever to affect Man on the British Isles, it is a fair bet that few would have guessed either the date or the event: in 1607 on January 30 at about 9am a wall of water surged from the Bristol Channel across the Somerset Levels (and, of course, Wales on the other side), killing 2,000 people and causing great economic loss through the deaths of cattle, sheep and horses and the disruption to agriculture.
As was vividly recounted by Professor Simon Haslett, a geographer from the University of Wales who is pleased to stray across into history, the facts, or very trustworthy deductions, are verifiable from parish records, early newspapers and eyewitness accounts.
What makes Professor Haslett’s position and that of his colleague from Australia, Dr Ted Bryant, unique is the contention that this was no ordinary flood — it was a tsunami. Professor Haslett cited a raft of pointers that led him to this conclusion.
Amazing though it may seem, it is possible to reconstruct the tide table for that week. It was a period of high tides — but no higher than was relatively commonplace and no higher than the sea wall normally withstood. Was there a storm or high wind that whipped the water over the wall and across the land? Seemingly not; reports suggest that it was rather a pleasant, calm and clear day.
And there is the way the water travelled: ordinary floodwater rises quickly enough, but not like a tidal wave. It was said, “No greyhound could have run faster than the wave.” And the accounts of what the shimmering wall of water actually looked like seem to describe a tsunami.
If it was a tsunami, what caused it? Professor Haslettt’s suggestion is not an earthquake, but a massive land (or rather seabed) slide, out in the channel, where the underwater-scape makes this hypothesis entirely feasible.
Flood rose to chancel of St Ben’s church in Glastonbury
An extract from Dr Malin Boyd's essay entitled St Benin's Pilgrimage, in the St Ben’s Yearbook of 1970.
(However, according to more recent study as in the article above, the event was not a storm.)
In January 1606/7 occurred the great storm which broke down the sea-walls at Huntspill and resulted in the flooding of the Brue levels with great loss of life and property. The floodwaters entered St Benedict’s Church for the first and only time in its history. To commemorate this disaster a tablet was placed on the chancel arch, inscribed “The breach of the Sea Flood was January 26th, 1606.” The level the waters reached was also marked.
In 1795 the sea-walls were again broken, but luckily without extensive flooding. The responsibility for the repair and maintenance of the wall was subsequently the subject of protracted lawsuits, eventually going to the House of Lords. It was proposed that all holders of land affected by the sea-wall should be held responsible. The plaque in St Benedict’s church was clear evidence that the lower part of Glastonbury was so affected, and so one night it conveniently disappeared.