the Strood at Mersea Island

On Friday (13th January), the Strood at Mersea Island in Essex was in the news – a severe sea storm surge warning was issued for the east coast, including Essex, on the BBC TV news channel at 11.29 am and repeated throughout that day. This included the instruction for the evacuation of residents at Mistley, Jaywick and West Mersea in north-east Essex, around Colchester. At 1.42 pm, the Strood was in the news – the Strood and surrounding marshland – when it was included in the storm surge warnings. Colchester’s Daily Gazette web-site also posted news items and information about the predicted storm surge, including two items just about the Strood. Fortunately, the storm surge did not materialise. It must be the first time that the Strood has been featured on the national news, although it is an important feature, being the only road connecting Mersea Island with mainland Essex. The Strood has always been an important infrastructure element and it has a long and very interesting history. It is also very important in archaeological terms.

The Strood is an artificial causeway (locally pronounced ‘causy’). It originated as a reinforced trackway across the marshes but, as the sea level rose over the centuries, the Strood causeway had to be constructed and its level progressively raised. It is about half-a-mile long and it is covered by water at high tide: it forms part of the main road from Colchester to Mersea Island. It was thought that the Strood was a Roman structure, but evidence produced by the excavation of a trench for a water pipeline in 1978 showed that it was constructed in AD 684-702 by the Anglo-Saxons. (‘Strood’ is also a word of Germanic or Saxon origin.) An article about the 1978 evidence was published in journal Essex Archaeology and History no 14 (EAH 14) in 1982 titled ‘Mersea Island: the Anglo-Saxon causeway’, written by Trust director Philip with Jennifer Hillam and Trust archaeologist Carl Crossan.

In 1978, a number of timber piles were recorded near the island end of the Strood over a distance of about 60 metres. These piles occurred at irregular intervals in two rows which seemed to be about 0.7  metres apart and which lay at an angle of about one degree to the line of the modern road. The tops of the piles lay about 1.6 metres below the present ground-level and they were sealed by several layers of surfacing. Eight layers were recorded, with the top layer (L1) being the modern road surface and L6 being the earliest road surface. Nine of the piles were removed and some of these were analysed by tree-ring dating and carbon-dating techniques to AD 694-702. This was important for the archaeology of the Strood but, remarkably, it was also of national archaeological importance: ‘… The Strood was the first site of this period to be absolutely dated in England…’ (J Hillam in EAH 14). The Strood dating curve was used to date another group of timbers and these two chronologies ‘… extend absolutely dated English reference curves back to A.D. 416; they thus give a dating framework for other Saxon sites …’ (J Hillam in EAH 14). Colchester Castle Museum now holds three of the timbers.

Trust director Philip concluded: ‘… The construction of the causeway was a major undertaking. Although difficult to estimate … it is possible that there are 15 to 20 rows of piles, each of which is 400 to 500 m. long. This would imply between three and five thousand piles. A project of this magnitude in c. A.D. 700 suggests the presence on the island of a sufficiently important feature to merit such a structure and also a substantial financial expenditure on the part of somebody or some organisation able to afford it …’ (EAH 14). A minster – a church with a small monastic community (later referred to as ‘Mersea Priory’*) – was founded in the remains of a Roman villa at West Mersea in the late 7th-early 8th century, perhaps to manage the island’s resources: flocks of sheep would have been grazed on the marshes and fish harvested from the rivers, estuary and sea. The Strood was constructed at the same time, as were four fish-traps around the island. During ‘the long eighth century’, the intensification of landscape use and exploitation of resources included some large infrastructure projects in England, including three causeways, ie at Mersea Island, on the River Thames at Oxford and in Somerset, and the famous Offa’s Dyke. Fish-traps for harvesting large quantities of fish were also constructed, including at Mersea Island (see The fields of Britannia by S Rippon, B Pears and C Smart, 2015). These infrastructure elements represent major investment by royal or monastic estates, or the early Church, to develop their assets and increase their revenues.

Interestingly, the Trust has recently conducted an archaeological project at Mersea Barrow (in 2014 and 2016), which has now been improved by Colchester Borough Council for visitors in terms of access and amenities (see CAT Report 992). We also undertake other fieldwork projects on Mersea Island.

See ‘Drivers risk salt water damage or worse as spring tide floods The Strood’ posted on the 14th January at www.gazette-news.co.uk/news/15024564.Drivers_risk_damage_as_spring_tide_floods_The_Strood/ .
You can read ‘Mersea Island: the Anglo-Saxon causeway’ and CAT Report 992, as well as articles on Mersea Island from EAS volumes 19, 20, 23 and 25 in our online archive at http://cat.essex.ac.uk/ . Visit the web-site of Mersea Island Museum at www.merseamuseum.org.uk/ . Also see CAG Bulletins 22 and 23 on the Colchester Archaeological Group web-site at http://caguk.net/ . See the Strood live via webcam at www.stroodcam.co.uk/ !

The images show a photo. of the Strood at high tide, looking towards the island; the plan of the part of the Strood discussed above, at the island end (from EAH 14); and the Church of Saint Peter and St Paul at West Mersea in 2015 (published on the web-site of the Essex Society for Archaeology and History at http://esah160.blogspot.co.uk/2015/05/essex-society-for-archaeology-and_25.html ). The photo. of the Strood was taken by Lee Garton in 2010 and generously published in the public domain on Panoramio: it was re-published in the public domain on Wikimedia at https://commons.wikimedia.org/wiki/File:Mersea_Causeway_The_Strood_-_panoramio_-_Lee_Garton_(4).jpg .

* The minster church was later rebuilt as the surviving parish Church of Saint Peter and Saint Paul. West Mersea ‘priory’ was important or profitable enough to be gifted to the Abbey of St Ouen at Rouen in France in 1046 by king Edward the Confessor, and the Abbey still held it in 1066, the year of the Norman conquest of England, and in 1086. In Domesday (1086), West Mersea was recorded as having a very large population and was assessed for a high rate of tax: East Mersea was recorded as having quite a large population and rate of tax, and included four fisheries.

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