"Dumped by Mersey Docks & Harbour Board"

Off the mouth of the Mersey is a group of wrecks whose recorded circumstances of loss are unusually matter-of-fact. They were not sunk by enemy action, lost during bad weather or abandoned following collision. Their records instead carry essentially the same explanation: “DUMPED BY MERSEY DOCKS & HARBOUR BOARD.”

Among the vessels within the disposal area are at least seventeen identified members of the British wartime FB-series of ferro-concrete barges. Their numbers range from FB 43 to FB 300, and their distribution across the seabed makes clear that this was not a single maritime casualty. It is the physical residue of a disposal operation: vessels which had been built to solve a wartime shortage, worked around British ports, and eventually became more troublesome to retain than to sink.

Concrete barges for a wartime port

The FBs formed part of a much larger British programme of ferro-concrete barge construction during the Second World War. Research by The Crete Fleet identifies 495 concrete barges constructed in Britain during the conflict. Of these, 294 were open cargo barges, while a further 201 were built as petrol barges.¹ The distinction matters, because a good deal of later writing has blurred together several quite different types of wartime concrete craft.

The open FB barges were working lighters rather than seagoing cargo ships. Their purpose was comparatively straightforward: moving cargo within ports and between ships, quays and dock systems at a time when conventional shipbuilding capacity and steel were needed elsewhere. Most were around 84 feet long, and their construction provided useful carrying capacity without making the same demands on conventional shipyards as an equivalent fleet built entirely in steel.²

They should not be confused with the prefabricated components of the Mulberry artificial harbours. The Crete Fleet's research specifically separates the British wartime ferro-concrete barges from the Mulberry programme, despite the connection which has often been made between surviving concrete barges and the Normandy landings.¹ The FBs were much less glamorous pieces of wartime infrastructure, but their role was no less practical: they were cargo-carrying working craft intended to increase the capacity of Britain's ports.

After the war

Victory did not immediately end the usefulness of the concrete barges. British ports still required lighterage, and a barge capable of carrying a substantial cargo did not cease to be useful simply because the emergency which had led to its construction was over. What did change was the number of craft available and the value attached to them. A large wartime fleet had become a substantial post-war surplus.

Surviving correspondence researched by The Crete Fleet gives a particularly useful view of this process around Liverpool. Concrete barges were concentrated in the dock system after the war, and attempts were made to find buyers and alternative uses for surplus vessels. Some were transferred elsewhere and continued working; others remained associated with Liverpool and the surrounding waterways for many years.²

The surviving histories of individual barges demonstrate that there was no single point at which the fleet ceased to exist. Some FBs remained useful well into the post-war period and passed into private ownership, while others were incorporated into harbour works, revetments and other civil-engineering structures. A redundant concrete barge was, after all, a large prefabricated piece of reinforced concrete. Where its usefulness as a vessel had ended, the structure itself could still have some value.³

Disposal was nevertheless an awkward problem. A steel barge reaching the end of its working life retained obvious scrap value. Ferro-concrete contained far less material worth recovering, while reducing a heavily reinforced hull to manageable pieces required time and labour. For some vessels, deliberate sinking was consequently a practical end to a working life which had already lasted considerably longer than the wartime circumstances for which they were built.

The disposal field

The wreck records on Wrecksite identify seventeen FB-series barges within the offshore group. Taken together, the numbers are as important as the individual wrecks because they show that the material on the seabed was drawn from widely separated parts of the wartime series.

This is not a consecutive block of vessel numbers. Seven of the identified wrecks fall between FB 43 and FB 118, while the remaining ten are concentrated between FB 265 and FB 300. On the evidence currently available it would be unsafe to infer too much from that division, but it does demonstrate that the disposal ground was not simply the graveyard of a single construction batch. Vessels originating at widely different positions within the FB numbering sequence ultimately reached the same disposal area.

Their positions tell the same story. They are not heaped together as the remains of barges sunk while rafted or lost in one accident. Individual wrecks are separated across the seabed, some lying relatively close to neighbours and others considerably farther apart. The arrangement is entirely consistent with repeated deliberate disposal rather than accidental loss.

FB 296

FB 296 is particularly useful because the wreck can be followed into the surviving hydrographic survey record. HMS Bulldog examined a concrete barge at 53°35.264′ N, 3°39.960′ W on 26 November 1987. The surrounding water depth was about 40 metres and the survey recorded a substantial target with scour extending to the east. Hydrosearch measurements produced a vertical height of 4.1 metres and an orientation of approximately 175°/355°.⁴

Importantly, the hydrographic record does not claim an unquestionable identification. Its wording is “tentatively identified as FB 296”. The wreck database consequently preserves an informed identification rather than the equivalent of a vessel name being physically read from the surviving structure. That qualification is worth retaining, particularly when considering the other FB numbers attached to wrecks in the group.⁴

What the survey establishes rather more firmly is the condition in which one of these concrete barges survived after disposal. More than twenty years after the likely period in which the Liverpool fleet was being reduced, the hull remained a substantial seabed obstruction, rising several metres above the bottom and generating measurable scour. The same durability which made reinforced concrete cumbersome to dismantle is one reason its remains can still be identified so clearly offshore.

Working craft rather than shipwrecks

The FBs are easy to overlook because they lack much of what normally attracts attention to a wreck. They had no engines, no naval careers and, in most cases, not even individual names. Their histories were concerned with cargoes shifted between ships and docks rather than voyages, battles or dramatic losses. Even the numbered identities are essentially administrative.

That is also what makes the group useful. The wreck field preserves evidence for an aspect of wartime maritime activity which rarely survives in such an obvious physical form. Ports depended on large fleets of workboats, lighters, dredgers, tugs and barges whose contribution was routine enough to attract relatively little attention. The concrete FB programme expanded one part of that infrastructure at a time when conventional materials and shipbuilding resources were under considerable pressure.

Their post-war histories are equally revealing. There was no immediate mass scrapping of the fleet. Some barges continued to work, some were sold, and some acquired entirely new roles as permanent pieces of harbour or coastal engineering. Their eventual disappearance therefore occurred gradually as individual vessels became uneconomic or unnecessary.

The group off Liverpool represents one outcome of that process. By the time these barges were taken offshore their value lay neither in their cargo capacity nor in the materials from which they were made. The cheapest practical treatment of a large, ageing concrete hull was ultimately to dispose of it intact.

What remains

Seen individually, none of these wrecks needs an elaborate explanation. Each is the remains of a fairly simple concrete lighter deliberately placed on the seabed. Seen collectively, however, the seventeen identified FBs preserve part of a much larger wartime fleet and its gradual removal from the Mersey after the war.

Their wreck-record description is unusually useful in that respect. “Dumped by Mersey Docks & Harbour Board” does not describe an accident or even a sinking in the ordinary maritime sense. It records a decision about obsolete port infrastructure. Barges which had once represented an economical response to wartime shortages had survived long enough to become a disposal problem.

The result remains visible on the seabed. FB 43, 72, 83, 86, 98, 116, 118, 265, 267, 275, 278, 289, 292, 295, 296, 297 and 300 now occupy a landscape quite different from the docks and sheltered waterways for which they were constructed. As individual vessels their records are incomplete, and some of the precise identifications deserve caution. As a group, however, they provide unusually tangible evidence for both the scale of Britain's wartime concrete-barge programme and the less frequently recorded business of disposing of it afterwards.