View source for 1607 Bristol Channel floods

{{Short description|Flooding in southwest England and south Wales}}
{{Use British English|date=March 2023}}
{{Use dmy dates|date=July 2024}}
{{Infobox weather event
| image      =Somerset.gif
| image-upright = 
| caption    = Contemporary depiction of the 1607 flood. The church is thought to be [[St Mary's Church, Nash|St Mary's]] at [[Nash, Newport|Nash]], near [[Newport, Wales|Newport]].<ref>{{Cite web|url=https://collections.library.yale.edu/catalog/15498058|title=1607, a true report of certaine wonderfull ouerflowings of waters, now lately in Summerset-shire, Norfolke, and other places of England : destroying many thousands of men, women, and children, ouerthrowing and bearing downe whole townes and villages, and drowning infinite numbers of sheepe and other cattle – Yale University Library|website=collections.library.yale.edu}}</ref>
}}{{Infobox weather event/History
| date       = 30 January 1607
}}{{Infobox weather event/Effects
| damages    = {{convert|200|sqmi|ha}} (est.) of farmland destroyed<ref name="2014bbc" />
| fatalities =2,000+ (est.)<ref name="2014bbc" />
| affected   = {{ubl|[[Bristol Channel]]|[[Severn Estuary]]}}
}}{{Infobox weather event/Footer}}
The '''Bristol Channel floods''' of 30 January 1607{{efn|name=New Style|Modern sources for this event commonly use the [[Gregorian calendar]]; however, contemporary records record the event as having happened on 20 January 1606/07 under the [[Julian calendar]] (see for example the flood plaque, in [[Church of St Mary Magdalene, Goldcliff|St Mary's Church]] pictured on this page where the date is given as 20 January 1606). For a more detailed explanation of these changes in calendar and dating styles, see [[Old Style and New Style dates]].}} drowned many people and destroyed a large amount of farmland and livestock during a [[flood]] in the [[Bristol Channel]]. The known tide heights, probable weather, extent and depth of flooding, and [[coastal flooding]] elsewhere in the [[British Isles]] on the same day all point to the cause being a [[storm surge]] rather than a [[tsunami]].

== Description ==
On 30 January 1607, around noon, the coasts of the [[Bristol Channel]] and [[Severn Estuary]] experienced coastal and tidal flooding in many counties. Pre-dating any modern flood defence construction low-lying land in [[Devon]], [[Somerset]], [[Gloucestershire]], and across [[South Wales]] was flooded. The devastation was particularly severe on the [[Wales|Welsh]] side, extending from [[Laugharne]] in [[Carmarthenshire]] to above [[Chepstow]] in [[Monmouthshire (historic)|Monmouthshire]]. [[Cardiff]] was the most badly affected town, with the foundations of [[St Mary's Church, Cardiff|St Mary's Church]] destroyed.{{citation needed|date=January 2022}}

The impact was extensive: it is estimated that 2,000 or more people were drowned; houses and villages were swept away; and an estimated {{convert|200|sqmi|ha|0}} of farmland and livestock were destroyed.<ref name="2014bbc">{{cite news |author=BBC staff |date=24 September 2014 |url=http://www.bbc.co.uk/somerset/content/articles/2007/01/30/somerset_flood_1607_anniversary_feature.shtml |title=The great flood of 1607: could it happen again? |access-date=20 February 2008 |work=BBC Somerset}}</ref> Along the coasts of the Bristol Channel and [[Severn Estuary]], local economies suffered greatly as a result of the flooding. 

The coast of [[Devon]] and the [[Somerset Levels]] as far inland as [[Glastonbury Tor]], {{convert|14|mi|km|0}} from the coast, were also affected.{{citation needed|date=January 2022}} The sea wall at [[Burnham-on-Sea]] gave way,<ref>{{cite web |url=http://www.somersetguide.co.uk/Burnham-on-Sea/ |title=Burnham on Sea |publisher=Somerset Guide |access-date=10 May 2010 |archive-url=https://web.archive.org/web/20110101154948/http://www.somersetguide.co.uk/Burnham-on-Sea/ |archive-date=1 January 2011 |url-status=dead }}</ref> and the water flowed over the low-lying levels and moors.

Thirty villages in Somerset were affected, including [[Brean]] which was "swallowed up" and where seven out of the nine houses were destroyed with 26 of the inhabitants dying. For ten days the [[Church of All Saints, Kingston Seymour|Church of All Saints]] at [[Kingston Seymour]], near [[Weston-super-Mare]], was filled with water to a depth of {{convert|5|ft|m}}. A chiselled mark remains showing that the maximum height of the water was 7.74 metres (25 feet 5 inches) above [[Ordnance Datum]].<ref>{{cite book |last=Hawkins |first=Desmond |year=1982 |title=Avalon and Sedgemoor |isbn=0-86299-016-5 |pages=[https://archive.org/details/avalonsedgemoor0000hawk/page/29 29–30] |publisher=A. Sutton |url=https://archive.org/details/avalonsedgemoor0000hawk/page/29 }}</ref><ref>{{cite book |url=http://forms2.rms.com/rs/729-DJX-565/images/fl_1607_bristol_channel_floods.pdf |title=1607 Bristol Channel Floods: 400-Year Retrospective RMS Special Report | publisher=Risk Management Solutions (RMS) |year=2007 |ref={{sfnRef|RMS|2007}} |page=12 }}</ref>

Contemporary accounts of the flood were written by people such as the [[Puritan]] [[pamphleteer]], William Jones:
{{Blockquote|text=as soon as the people of those Countries, perceived that it was the violence of the Waters of the raging Seas, and that they began to exceede the compasse of their accustomed boundes, and making so furiously towardes them. happy were they that could make the best, and most speed away, many of them, leaving all their goods and substance, to the merciles Waters, being glad to escape away with life themselues: But so violent and swift were the outragiouse waves, that pursued one an other, with such vehemencie, and the Waters multiplying so much in so short a time, that in lesse then five houres space most part of those cuntreys (and especially the places which lay lowe) were all over flowen, and many hundreds of people both men women, and children were then quite devoured, by these outragious waters, such was the furie of the waves, of the Seas, the one of them dryving the other forwardes with such force and swiftnes, that it is almost incredible for any to beleeve the same....Many there were which fled into the tops of high trees, and there were inforced to abide some three daies, some more, and some lesse, without any victuals at all, there suffring much colde besides many other calamities, and...through ever much hunger and cold, some of them fell down againe out of the Trees, and so were like to perish for want of succour. Othersame, sate in the tops of high Trees as aforesaid, beholding their wives, children, and servants, swimming (remediles of all succour) in the Waters. Other some sitting in the tops of Trees might behold their houses overflowne with the waters. some their houses caryed quite away: and no signe or token left there of them.<ref>{{cite book |author=William Jones of Usk|title=Gods warning to his people of England By the great over-flowing of the waters or floudes lately hapned in South-wales and many other places. Wherein is described the great losses, and wonderfull damages, that hapned thereby: by the drowning of many townes and villages, to the utter undooing of many thousandes of people.|url=https://quod.lib.umich.edu/e/eebo/A00015.0001.001/1:2?rgn=div1;view=fulltext|year=1607|publisher=Printed by R. Blower for W. Barley, and Io. Bayly, and are to besolde in Gratious street}}</ref>|source="Gods warning to his people of England By the great over-flowing of the waters..." by William Jones, 1607}}

== Cause ==
The flooding is thought to have been caused by a high astronomical spring tide combined with severe weather, namely low atmospheric pressure bringing strong winds and a storm surge.<ref name="GSL-Long">{{cite journal|title=Cataloguing tsunami events in the UK|url=https://sp.lyellcollection.org/content/456/1/143|doi=10.1144/SP456.10|journal=Geological Society, London, Special Publications|year=2017|last1=Long |first1=Dave |volume=456 |pages=143–165 |s2cid=134094076 |url-access=subscription}}</ref><ref name="RMS">{{citation|title=1607 Bristol Channel Floods: 400-year Retrospective Risk Management Solutions Report|publisher=Risk Management Solutions, Newark CA, USA|url=https://forms2.rms.com/rs/729-DJX-565/images/fl_1607_bristol_channel_floods.pdf|year=2007}}</ref> The [[spring tide]] in the Bristol Channel on 30 January 1607 reached a height of {{Convert|7.86|m|ftin}}. This occurred in combination with a severe south-westerly gale with peak winds measured at [[Barnstaple]] from 3am to noon, and coastal flooding in East Anglia at night on the 30th, both of which are consistent with a storm tracking eastwards.<ref name="HH" /> It has been demonstrated that the tide and weather event that occurred on this date were capable of generating a storm surge consistent with the observed inundation.<ref name="HH">{{cite journal |last1=Horsburgh |first1=K. J. |last2=Horritt |first2=M.|year=2006 |title=The Bristol Channel floods of 1607 – reconstruction and analysis |journal=Weather |volume=61 |number=10 |pages=272–277 |doi=10.1256/wea.133.05|bibcode=2006Wthr...61..272H |doi-access= |s2cid=123099829 }}</ref><ref name="RMS" />

== Tsunami hypothesis ==
A 2002 research paper, following investigations by Professor Simon Haslett of [[Bath Spa University]] and Australian geologist Ted Bryant of the [[University of Wollongong]], suggested that the flooding may have been caused by a tsunami, after the authors had read some eyewitness accounts in the historical reports which described the flood.<ref>{{cite news |author=BBC staff |date=4 April 2005|url=http://news.bbc.co.uk/1/hi/wales/4397679.stm  | title=Tsunami theory of flood disaster |publisher=[[BBC News Online]] |access-date=13 November 2010}}</ref><ref>{{cite journal |last1=Bryant |first1=Edward |last2=Haslett |first2=Simon |year=2007 |title=Catastrophic Wave Erosion, Bristol Channel, United Kingdom: Impact of Tsunami? |journal=Journal of Geology |url=http://ro.uow.edu.au/cgi/viewcontent.cgi?article=1059&amp;context=scipapers |doi=10.1086/512750 |volume=115 |issue=3 |pages=253–270 |bibcode=2007JG....115..253B|s2cid=53456645 |url-access=subscription }}</ref><ref>{{cite journal |last1=Bryant  |first1=Edward  |last2=Haslett  |first2=Simon |year=2002 |url=http://ro.uow.edu.au/cgi/viewcontent.cgi?article=1100&context=scipapers |title=Was the AD 1607 Coastal Flooding Event in the Severn Estuary and Bristol Channel (UK) Due to a Tsunami |journal=Archaeology in the Severn Estuary |issue=13 |pages=163–167 |issn=1354-7089}}</ref> The [[British Geological Survey]] has suggested that, as there is no evidence of a landslide off the continental shelf, a tsunami would most likely have been caused by an earthquake on a known unstable [[Geologic fault|fault]] off the coast of southwest Ireland, causing the vertical displacement of the sea floor.<ref>{{harvnb|BBC staff|2005}}</ref> One contemporary report describes an earth tremor on the morning of the flood;<ref>{{cite book |last=Haslett |first=Simon K. |year=2010 |title=Somerset Landscapes: Geology and landforms |publisher=Blackbarn Books |location=Usk |isbn=978-1-4564-1631-7|page=159}}</ref> however, other sources date this earthquake to a few months after the event.<ref name=":0">{{Cite web|url=http://www.volcanocafe.org/the-bristol-tsunami-of-1607/|title=The Bristol Tsunami|last=Zijlstra|first=Albert|date=16 June 2016|website=Volcanocafe|access-date=10 April 2018}}</ref>

Haslett and Bryant's evidence for the tsunami hypothesis included massive boulders that had been displaced up the beach by enormous force; a layer up to {{convert|8|in|cm|0}} thick composed of sand, shells and stones within an otherwise constant deposit of mud that was found in boreholes from [[Devon]] to [[Gloucestershire]] and the [[Gower Peninsula]]; and rock erosion characteristic of high water velocities throughout the [[Bristol Channel|Severn Estuary]].<ref>{{harvnb|Bryant|Haslett|2007|pp=253–270}}</ref><ref>{{cite journal |last1=Haslett |first1=Simon |last2=Bryant |first2=Edward |year=2004  |title=The AD 1607 Coastal Flood in the Bristol Channel and Severn Estuary: Historical Records from Devon and Cornwall (UK) |journal=Archaeology in the Severn Estuary |issue=15 |pages=81–89 |issn=1354-7089}}</ref> However, because of high wave energy conditions it is not methodologically possible to distinguish between storm and tsunami boulder deposits on North Atlantic coasts.<ref>{{Cite journal |last1=Costa |first1=Pedro J. M. |last2=Dawson |first2=Sue |last3=Ramalho |first3=Ricardo S. |last4=Engel |first4=Max |last5=Dourado |first5=Francisco |last6=Bosnic |first6=Ivana |last7=Andrade |first7=César |date=1 January 2021 |title=A review on onshore tsunami deposits along the Atlantic coasts |url=https://www.sciencedirect.com/science/article/pii/S0012825220304876 |journal=Earth-Science Reviews |language=en |volume=212 |pages=103441 |doi=10.1016/j.earscirev.2020.103441 |bibcode=2021ESRv..21203441C |s2cid=228880506 |issn=0012-8252|url-access=subscription }}</ref>

In attributing the flood to a storm surge in their 2006 paper,<ref name="HH" /> Horsburgh and Horritt show that those proposing a tsunami hypothesis underestimate the volume of water and coastal damage involved in storm surges, and fail to account for flooding on the opposite side of the country on the same day. There is also a lack of evidence for the event affecting [[West Wales]], [[Cornwall]], or southern [[Ireland]]. Their tsunami modelling showed that it would not be possible for a tsunami not to affect these areas, while causing flooding elsewhere in the country. Contemporary sources also indicate the flooding proceeded for a period of five hours, which is consistent with a storm surge rather than a tsunami.<ref name="HH" /><ref>{{cite book|title=The Severn Tsunami?: The Story of Britain's Greatest Natural Disaster|author=Mike Hall|publisher=The History Press|year=2013|chapter=5: The Cause of the Disaster|isbn=978-0-7524-7015-3|url=https://books.google.com/books?id=uek6AwAAQBAJ}}</ref>

== Future recurrence ==

The risk of coastal flooding is highlighted in the UK National Risk Register [https://access-national-risk-register.service.cabinetoffice.gov.uk/risk-scenario/coastal-flooding].{{fv|date=January 2025}} While the risk of similar events in the foreseeable future is considered to be low, thanks to advances in defences and flood warning, it is estimated that the potential cost caused by comparable flooding to residential, commercial, industrial, and agricultural property could range from £7 billion to £13 billion at 2007 insured values.<ref>{{harvnb|RMS|2007|p=16}}</ref> There has also been concern that the [[nuclear power stations]] at [[Hinkley Point]] and [[Oldbury Nuclear Power Station|Oldbury]] could be endangered.<ref>{{harvnb|RMS|2007|p=17}}</ref>

== Commemorations ==
[[File:754586 a96910f6.jpg|300px|thumb|Flood plaque, in [[Church of St Mary Magdalene, Goldcliff|St Mary's Church]], [[Goldcliff]], near [[Newport, Wales|Newport]].{{efn|name=New Style}}]]
A number of commemorative plaques still remain, up to {{convert|8|ft|m}} above sea level, showing how high the waters rose on the sides of surviving churches. The one inside the [[Church of St Mary Magdalene, Goldcliff|Church of St Mary Magadalene]] at [[Goldcliff]], [[Newport, Wales|Newport]] is a small brass plaque, inside on the north wall near the altar, today about {{convert|3|feet|1}} above ground level, marking the height of the flood waters. The plaque records the year as 1606 because, under the [[Julian calendar]] in use at that time, the new year did not start until [[Lady Day]], 25 March. The resultant financial loss in the parish was estimated as £5,000 (equivalent to £{{Inflation|UK|0.005|1607|r=1}}&nbsp;million in {{Inflation/year|UK}}).<ref>The contemporary brass plaque in [[Church of St Mary Magdalene, Goldcliff]] reads: "AND IN THIS PARISH THEARE WAS LOST 5000 AND ODD POWNDS BESIDES XXII PEOPLE WAS IN THIS PARRISH DROWND"</ref>{{Inflation/fn|UK}}

The flood was commemorated in a contemporary pamphlet entitled ''God's warning to the people of England by the great overflowing of the waters or floods'', by William Jones.<ref>{{cite web |url=http://website.lineone.net/~mike.kohnstamm/flood/jonespamphlet/godswarning.html |title=Gods Warning to his people of England. |access-date=20 February 2008 |work=The British Library |archive-date=4 December 2017 |archive-url=https://web.archive.org/web/20171204062750/http://website.lineone.net/%7Emike.kohnstamm/flood/jonespamphlet/godswarning.html |url-status=dead }}</ref>

On the 400th anniversary, 30 January 2007, BBC for the [[Somerset]] area looked at the possible causes and asked whether it could happen again in the county. [[BBC Somerset Sound]] broadcast an anniversary programme and a special report was filed for ''[[BBC Points West]]''.<ref>{{harvnb|BBC staff|2014}}</ref>

== See also ==
* [[List of natural disasters in the United Kingdom]]
* [[List of disasters in Great Britain and Ireland by death toll]]
* [[List of natural disasters by death toll#Ten deadliest tsunamis|List of Deadliest Tsunamis]]
* [[Geology of Great Britain]]
* [[Tsunamis affecting the British Isles]]
* [[1999 Blayais Nuclear Power Plant flood]]

== Notes ==
{{notelist}}

== References ==
{{Reflist}}

=== Other sources ===

* {{cite news
  |title=Geology: Ooo arhh! A Tsunami May Have Struck Britain 400 Years Ago
  |newspaper=[[The Economist]]
  |date=5 May 2007
|page=83
}}

== External links ==
* [https://www.bbc.co.uk/programmes/b0078w1y "The Killer Wave of 1607"] – BBC's ''[[Timewatch]]'', 1 April 2005
* [http://www.bbc.co.uk/somerset/content/articles/2007/01/30/somerset_flood_1607_anniversary_feature.shtml The great flood of 1607: could it happen again? (BBC Somerset)]
* [http://news.bbc.co.uk/1/hi/england/6311527.stm Anniversary of 1607 killer wave (BBC News)]
* [http://website.lineone.net/~mike.kohnstamm/flood Mike Kohnstamm: Text of original sources and local pictures] {{Webarchive|url=https://web.archive.org/web/20080405174926/http://website.lineone.net/~mike.kohnstamm/flood/ |date=5 April 2008 }}

{{Weather events in the United Kingdom}}

[[Category:Floods in the United Kingdom]]
[[Category:1607 disasters]]
[[Category:1600s natural disasters]]
[[Category:1607 in England]]
[[Category:Natural disasters in Wales]]
[[Category:1607 in Wales]]
[[Category:Water in Wales]]
[[Category:Disasters in Somerset]]
[[Category:Bristol Channel|Floods]]
[[Category:17th-century floods]]
[[Category:17th century in Somerset]]