50 Years of Protecting Shipwrecks

July 18, 2023December 20, 2024 ~ Serena ~ Leave a comment

CGI image of 'ship-shape' outline on a sandy seabed with scattered guns inside, and turquoise sea overhead — Still from dive trail of the protected wreck of the *Stirling Castle* (1703) on the Goodwin Sands
© Trendive

For this blog we welcome our Historic England colleague, Hefin Meara, National Listing Adviser – Marine, who takes us on a voyage from the beginnings of the Protection of Wrecks Act in 1973 to Historic England’s work in protecting shipwrecks today.

The origins of the Protection of Wrecks Act

July 2023 sees the 50^th anniversary of the Protection of Wrecks Act. The Act was brought into effect in order to prevent damage and destruction of historic shipwrecks as a result of indiscriminate salvage that was taking place, causing public outcry. The late 1960s and early 1970s had seen a great increase in the use of diving equipment, with scuba diving becoming an affordable and accessible pastime. This meant that the large amount of historic shipwrecks that were in relatively easily accessible, shallow depth were suddenly open to access. Several high-profile incidents in the early years encouraged the development of the Act, which was put forward as a private members’ bill.

It was envisioned that only a small number of sites would need to be designated, and that they would be de-designated fairly soon after any significant threat was removed, following the successful completion of any work being undertaken.

One of the key incidents involved in the development of the Act was the salvage on one of England’s most significant shipwrecks, HMS Association (1707), lost among the Isles of Scilly in an unparalleled naval disaster which led to the Longitude Act of 1714. Large quantities of material were removed from this site by competing groups of salvors, which meant that information about the site was lost, as they were not recorded archaeologically.

The first site to be designated under the Act was a 16^th century wreck in the Cattewater estuary, Plymouth. This wreck is still designated to this day and is being investigated by Licensee Martin Read. A substantial portion of structure and a large assemblage of finds were recovered in the 1970s. Current research being undertaken by Licensee Martin Read has been reassessing the finds assemblage, and researching potential candidates for the identity of the wreck. (See Martin’s blog on this site about Cattewater celebrating the 45th anniversary of the Act.)

Since then a wide variety of sites have been designated, forming a representative sample of the broad range of vessels that would have been seen off the English coast over the centuries. These range from Late Bronze Age cargo scatters to the remains of early 20th century submarines and a near complete steam trawler of the First World War era. The most recently designated sites include two wrecks located on the Shingles Bank off the Isle of Wight discovered by Martin Pritchard, and a 13^th century wreck in Poole Bay, discovered by charter boat skipper Trevor Small.

Diver to centre right shining a light on a grave slab on the seabed with intact foliate decoration in relief even after 8 centuries underwater. — Decorated 13th century gravestone which helped to date the protected wreck in Poole Bay, and shed new light on the production and transport of grave slabs. © Bournemouth University

Why not explore all of these on the Heritage List for England? Go straight to Advanced Search and turn off all filters except Protected Wreck Site to explore all 57 of the designated wreck sites in English waters.

Location map of the 57 wrecks designated in English waters under the Protection of Wrecks Act 1973

Access to shipwrecks designated under Act is by a licence, which is administered by Historic England on behalf of the Department for Culture, Media and Sport (DCMS). The role of the Licensee has played a vital part in the ongoing management of sites designated under the Act, with Licensees operating as the custodians for these nationally important archaeological sites. In recent years there have been over 200 Licensees and team members active on England’s Protected Wreck sites. We would like to say a huge thank you to all licensees past and present for their hard work and dedication in monitoring and investigating the Protected Wrecks.

Changes over the last 50 years

Circumstances have changed considerably since the Act first came into effect 50 years ago. In practice designation is permanent, rather than temporary, for example. Sites which were once considered inaccessible, due to their depth, are now fairly easy to access as a result of developments in diving technology. Furthermore, the leaps and bounds which have been made in the development of geophysical survey technology allow for the discovery and investigation of many new shipwrecks.

Seabed development is currently proceeding at a pace which has never been seen before, with a massive increase in offshore renewable capacity. For example, the production of electricity from offshore wind has risen from an operational capacity of under 700MW in 2009 to more than 10,000MW by the end of 2020. Proposals for decarbonising all sectors of the UK economy to meet net zero target by 2050 includes 50GW of offshore wind delivery by 2030.[1] In addition, approximately 21 million tonnes of aggregate were extracted from the seabed last year across multiple different licence areas.[2] As a result many more shipwreck sites are discovered each year.

The management of shipwrecks designated under the Protection of Wrecks Act became the responsibility of Historic England following the National Heritage Act 2002, which modified functions to include securing the preservation of, and promoting the public’s enjoyment of, ancient monuments in, on, or under the seabed. The Act also transferred the administrative functions relating to the Protection of Wrecks Act 1973 to Historic England, and provided the ability to grant-aid projects in relation to Protected Wreck sites.

It is our role to ensure that all activities on protected wreck sites are undertaken to the highest standards, which includes for example, being in line with the rules of the Annex to the UNESCO Convention on the Protection of the Underwater Cultural Heritage, which the UK government has adopted as best practice.

How our role has changed

How has our role in the care of these sites changed in the 20-plus years since we took on responsibility for their management?

Diver exploring a seaweed-encrusted cannon nearly upright on the seabed in murky conditions with heavy seaweed cover. — **Colossus** Dive Trail © CISMAS
Physical dive trails like these, allowing visitors the experience of exploring protected wreck sites, are now being supplemented by virtual trails reaching wider audiences.

We have worked hard to ensure that protected wreck sites are accessible to all. We’ve encouraged responsible access to the wrecks on the seabed through the commissioning of physical dive trails on the seabed. Mindful that not everyone can dive, we’ve also developed a programme of virtual dive trails which allows those that can’t dive to access the sites without getting wet. To date there are 18 virtual dive trails accessible from the Historic England website, with plans for new ones in the pipeline. These can all be seen in our StoryMap.

As well as managing the licensing of access to protected wreck sites on behalf of DCMS, and providing grant funding for several projects being undertaken on these sites, we are also looking towards the future of heritage protection at sea. We have commissioned several projects with partner agencies and contractors which will improve the protection of heritage assets offshore and secure their preservation for the future.

One of the ways that we’re working to ensure that sites are better protected is through a project being undertaken by MSDS Marine on the development of a product for the forensic marking of material on protected wreck sites. This is similar to the kind of material used to mark lead on the church roofs at risk of theft. The product has been in development for some time, and will be deployed on several wrecks this summer. The marker will be a deterrent to those looking to lift material from sites, and will also allow for investigation and prosecution, should the worst happen and material be taken from the sites. We’ll have more information to reveal about this project later this year.

We’ve also commissioned a project from the Maritime Archaeology Sea Trust (MAST) and OceanMind, who have developed the Maritime Observatory. This project will use a combination of satellite data, artificial and human intelligence, to detect patterns of behaviour from vessels around protected wreck sites, in a pilot focused on Poole Bay and the Goodwin Sands. This will aim to detect any unauthorised activity, such as unlicensed diving, as well as potential threats to the sites from other activities. This project will be reporting back later this summer.

It is not just Historic England working to monitor and care for Protected Wrecks offshore: we work closely with partner organisations who also have the resources and capacity to investigate and monitor these sites. These include the Receiver of Wreck at the Maritime and Coastguard Agency (MCGA), the Marine Management Organisation (MMO), as well as heritage crime officers in various police forces. In order to strengthen this partnership working, we’ve commissioned Plymouth University to produce the Common Enforcement Manual for Heritage Crime at Sea. This will enable improved cooperation and inter-agency working.

Marking 50 years of the Act

In order to mark the 50^th year of the Act, we’ve commissioned several projects. These include a broad range of projects which celebrate exciting discoveries, research projects and investigations relating to Protected Wrecks, engage the public and reach new audiences and participants. We’re also reflecting on how the Act has shaped the heritage sector and considering the implications for sector resilience in future, and drawing lessons from the last 50 years that can inform the next 50 years of protecting marine heritage.

We’ve been particularly keen to ensure that we’re not just sharing our stories with the same traditional audiences. We’ve often taken stands to coastal locations while fieldwork is under way, such as the open days in relation to the Rooswijk project in Ramsgate. This year we’re heading inland to bring the story of protected wrecks to people in landlocked counties, with multiple events across locations in Derbyshire and Nottinghamshire, reaching new audiences and exploring links between these locations and the sea. Check out the calendar of events (until 1 October 2023).

Visitors of all ages explore shells, bones and artefacts from the sea with a helper from MSDS Marine: a Protected Wreck Roadshow banner is in the background — Visitors exploring maritime archaeology finds at one of the ‘Landlocked & Looking Out’ #PWA50 roadshows, 2023 © MSDS Marine

Our work has also often focused on the south coast, so this year we’ve commissioned a project from Tees Archaeology to examine and promote the Seaton Carew protected wreck, engaging with a new audience on the north-east coast.

The timbers of a wreck on a shingle beach fill up with water as the tide comes in, under heavy cloud cover. — Seaton Carew protected wreck, © P Grainger

As part of the call for projects, we were eager to engage with groups we’ve not worked with previously. Therefore we were delighted to receive an application from the volunteer-run Teign Heritage Centre, which holds material related to the late 16th century Church Rocks protected wreck. The centre will use the funding to enhance the museum display, and to enable the deposition of the site archive with the Archaeology Data Service, including dive logs, site drawings, reports and photographs.

We’ve commissioned Cornwall Archaeological Unit to undertake a project looking at the links between protected shipwrecks and the wider landscape. This project includes drone survey of wreck salvage activity in the vicinity of Gunwalloe, and a GPR survey of a mound site, potentially covering a wreck burial or a barrow which was formerly a coastal mark, or perhaps the location of a lost coastal settlement coeval with the nearby wreck of the St Anthony lost in 1527. This project will conclude with an open event for providing identification of beach finds and the sharing of local knowledge.

As mentioned earlier, the contribution of volunteer licensees is vital for the care and monitoring of protected wreck sites. We’ve commissioned the Nautical Archaeology Society to produce a series of bite-sized online training session to assist current and prospective licensees. These cover a variety of topics, including how to apply for a licence, how to help reduce heritage crime, how to apply for funding, and many others. These sessions are recorded and will be made available online in perpetuity – check out the playlist so far.

We’re also eager to ensure that new people come forward to become licensees. We’re conscious that the demographic has been largely male throughout the years. As a result we commissioned the Maritime Archaeology Trust to undertake a project to investigate the engagement of women with protected wreck sites, through a combination of desk-based research, interviews, and an online survey, which is still open for further responses (July 2023).

The history of those involved with protected wreck sites is fascinating and MSDS Marine will be working with underwater cameraman Michael Pitts to create a short film to communicate this important work on protected wreck sites. The film will celebrate the role of volunteers in the management of wreck sites over the years, reflect on the contribution to knowledge made by the investigation of protected wreck sites, and emphasise the need for new volunteers to become involved in future.

Finally we’ve commissioned the Chartered Institute for Archaeologists (CIfA) to undertake a critical analysis of the Protection of Wrecks Act, and to facilitate a discussion of how things can be improved. This will include a seminar to reflect on what has been achieved and how we can seek to update and improve policy and practice in future. The seminar will take place in November, and there is an online survey that you can complete in advance to inform the discussion on the day.

Conclusion

As you can see, this is a busy year for work in relation to protected wrecks at Historic England. We’ve many projects and events looking at long term legacy, engaging the public, sharing the successes and looking critically at how we can do things better. This is all as well as our continuing programme of work relating to assessing sites for protection, monitoring existing sites, and developing new ways to protect sites from unauthorised activities.

From Bronze Age scatters to 20th century conflict archaeology via the Mary Rose, here’s how to discover protected wrecks in more detail . . .

Learn more

NEW! Our colleague Angela Middleton, Senior Archaeological Conservator, explains conservation of the finds from the protected wreck of the Rooswijk https://www.youtube.com/watch?v=ytaNnO9aTzE

What are protected wreck sites? Further information and links to guidance

Explore the Dive Trails – your chance to explore 18 of the protected wreck sites without getting your feet wet!

Search the List – discover all 57 protected wreck sites (uncheck all Heritage Categories except Protected Wreck Sites)

Check out our past blogs for the Act’s 45th anniversary:

Martin Read introduces the Cattewater Wreck
Ian Friel writes about the Grace Dieu

Footnotes

[1] https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1167856/offshore-wind-investment-roadmap.pdf

[2] https://www.thecrownestate.co.uk/en-gb/media-and-insights/news/the-crown-estate-and-bmapa-release-annual-area-involved-report-and-2022-aggregates-review/

On the cleaning of metal finds from the London and the Rooswijk

March 12, 2018March 24, 2018 ~ Serena ~ 1 Comment

I am pleased to introduce this week as my guest blogger Elisabeth Kuiper, who has just completed an internship with Historic England. She tells us about her recent experiences in the conservation of metal artefacts from two designated shipwrecks:

Most historic ships are full of iron: think of nails and bolts in all sizes, ship equipment, rigging elements, chains, anchors, iron cannons and all sorts of different tools used on the ship. This iron, in the unfortunate event of ending up on the seabed, usually grows very bulky corrosion products eventually covering the original surface of an object. Iron objects from a maritime archaeological context are thus very often found as mysterious and unrecognisable lumps, known as concretion, as they have become covered by a thick formless mass of corrosion which can incorporate sediment and shells, and also different objects in the vicinity. In order to understand the concretion and what is, or used to be, inside it, the conservator uses X-radiography. X-radiography gives the opportunity to investigate the concretion without damaging it: dense areas or voids will show up on the image and so may be able to tell what has caused the concretion.

Once it is clear that the concretion may hold something worth investigating further, the conservator will start off mechanically cleaning it. Corrosion products are taken off layer by layer until the original surface of the object is found. In the process of cleaning other artefacts which may not have been seen previously on the x-radiograph, can be found trapped in the corrosion layers, for example, pieces of glass, ceramics or small metal objects.

Unlike any other metal, in an advanced stage in the corrosion process the iron of the original object can have migrated entirely to its corrosion layers, and we are left with a void that retains the shape of the object precisely. If needed, these voids can be filled with a silicone rubber or casting resin. Once all concretion is removed the conservator is left with a perfect cast of the object that would otherwise be lost forever.

I am a Professional Doctorate student in conservation and restoration at the University of Amsterdam, specialising in metal conservation, and have been working at Historic England on an archaeological conservation work placement for the past months. My main focus during my time at Historic England was the remedial and investigative conservation of finds from the protected wreck sites of the Rooswijk and the London. The London was a Royal Navy warship that went down in the 1665 after an accidental explosion aboard the ship, and many different objects were recovered during the salvage operations between 2014 and 2016.

The Rooswijk was a Dutch East Indiaman that ran aground on the Goodwin Sands, off Kent, in the winter of 1740. The shipwreck was partly excavated and recorded in the summer of 2017, after which the finds were taken to Historic England storage facilities for assessment, analysis and conservation.

During my time at Historic England I have worked on quite a diverse range of finds from both wreck sites, but what they all had in common was the various amounts of iron corrosion on the object’s surface. As previously mentioned, this is quite typical for maritime archaeological artefacts, which (as we will see) can even be totally enveloped in iron corrosion. A few of the more straightforward objects I have worked on were from the London:

Hammer laid vertically, showing concretion at the head, with scale marker and label to left. x-ray of hammer, laid diagonally with head at top left, concretion showing up as white around the head. Hammer laid vertically showing head with concretion removed, scale rule and label to left

Figure 1. Different stages of conservation process on hammer from the London: before treatment (left), x-radiograph (middle) and after cleaning treatment (right) © Historic England

In Figure 1 above we see a hammer, with iron corrosion products covering the original surface. The hammer was cleaned using a pneumatic tool called an air-scribe, which can be seen as a small jackhammer. It is ideal for removing concrete-like iron corrosion products, with the x-radiograph was used as a guide during the cleaning. When looked at carefully, the x-radiograph clearly shows the typical lamellar structure of corroded wrought iron. Wrought iron is essentially pure iron containing less than 0.2% carbon by weight. The main compositional variation is in the presence of slag inclusions. When worked these slag inclusions are forced out in the direction of working. On the seabed not only does the metal surface corrode, but also the walls of the slag inclusions, as seawater is able to penetrate deep into the metal. As a result the metal shows a wood grain-like appearance, typical of wrought iron recovered from shipwrecks.

The same became clearly visible as corrosion was cleaned away on a rigging element called a deadeye:

Deadeye with rust-coloured concreted surface, label and scale rule to left Deadeye following removal of concretion, showing its shape and dark colour more clearly. Scale rule below the object.

Up to now I have discussed corroded iron objects. Surprisingly, it’s not only objects made from iron that can become covered by a thick iron concretion crust. As we will see in the next images, copper alloy objects can also become unrecognisably changed due to maritime corrosion processes:

Pan body showing rust-coloured concretion, particularly around the edges, with scale rule and yellow archaeological tag below. Pan after cleaning, with concretion removed, showing a darker metal colour and some discolouration. Scale rule and yellow tag below.

The artefact shown here is a copper-zinc alloy object, presumably a pan of some sort. Probably it will have had a handle that was riveted to the pan itself. These rivets were already visible on the x-radiograph, but were uncovered during cleaning.

Detail of 4 rivets on rim of pan, with centimetre scale

Figure 4. Detail of rivets on rim of pan after treatment (above) with corresponding features visible on x-radiograph prior to treatment (below) © Historic England

x ray of whole pan, with 4 rivets showing up as small white round features at top

Cleaning of maritime archaeological finds can be rewarding and satisfying work, in the sense that the disfiguring corrosion layers are slowly removed to reveal a recognisable object once more. Sometimes these objects can even be in quite a good condition. The cleaning of concreted artefacts can almost be seen as a mini-excavation. To illustrate this, I will show one last treatment on a concretion, which furthermore posed quite a challenge:

Irregular lump of concretion with shells and other material embedded, scale rule and yellow number tag at bottom

Fig 6

Figure 6. X-radiograph of concretion in Fig 5 before cleaning treatment, where rings, a coin and many beads (lighter areas) as well as different sizes of nails (darker areas) become apparent © Historic England

In this case, cleaning of the concretion was more of a challenge because of the mixture of elements and materials in it. The concretion consists of approximately 17 copper alloy rings, 1 silver coin and over 400 tiny glass beads. What was left of the iron (mostly nails and/or small bars), as explained earlier, were just voids. The concretion itself proved to be a harder material than the glass beads, which tended to shatter when the air-scribe came close. Mechanical means thus did not seem to suffice to remove the beads from the concretion, but a chemical treatment would be difficult to select, as the other metals would react to the chemicals as well as the iron concretion. As a first step, the concretion was mechanically cleaned until beads and artefacts, including voids, started appearing:

Detail of artefacts in concretion revealed after cleaning, such as rings and yellow beads

Figure 7. Reverse side of the concretion from the Rooswijk, with detail photo above left; the complete artefact below right, after initial mechanical cleaning; notice the yellow beads, copper alloy rings and coin © Historic England

The same lump as in figure 6 following initial cleaning, with rings, beads and coins now visible. Yellow tag on left, scale rule on object

Detail of obverse side of concretion, with rings visible on the left: scale rule on object on the right, yellow tag below

Figure 8. Obverse side concretion from the Rooswijk after initial mechanical cleaning; notice the voids in the shape of a nail (on the right) and small bar-like shapes © Historic England

Because initial research proved the voids to be ‘just nails’, the decision was made to record them as best as possible, but then to sacrifice them in the bigger scheme of things. This way, the concretion could be broken apart in smaller pieces that offered the opportunity to treat them separately from the coin and rings. This work is still ongoing and consists of a combination of mechanical and chemical treatments in order to gently dislodge all the different objects from the concretion for further study.

Thank you to Elisabeth for sharing the problems and processes of conserving concreted objects from the London and the Rooswijk, and which complement previous blogs by our conservators: see links below. We hope she has enjoyed her time with us and wish her all the best for the future.

For more archaeological conservation stories on the varied artefacts from the London:

The London: A conservator’s tool-kit

Conservation of artefacts from the London

How to do . . . archaeological conservation

Glossary:

lamellar: