The mystery of the ferro-concrete ships in the River Wear
Even for relatively recent wrecks such as those of the Second World War, little is sometimes known. Vessels lost offshore, running without convoy and mined in the dark, sinking without witness, are understandable mysteries. Yet there remain ships lost inshore about which very little is really known, and what remains are fragments of a story.
How much more interesting is that story when it involves some of the most unusual vessels among England’s recorded losses? Here is the intertwined story of the Cretestem, recorded as lost in May 1943, and the Cretehawser, 1942.
Towards the end of the First World War steel was both in short supply and in great demand for shipbuilding to replace tonnage lost to war causes. Among the remedies put into execution towards the end of the war, and into the immediate post-war period, was the construction of ferro-concrete ships as barges and tugs. Ferro-concrete ships had been produced in other countries for some years and the adoption of the technology met a significant need. All such British ships of this era had the prefix Crete- as a nod to their common build material, while the naming pattern demonstrated that they were built under official programmes (much as the prefix War had done for ships built under the War Standard programme). 
(The Hughes & Stirling collection shows concrete vessels under construction 1918-19 and can be explored online in the Historic England Archive.)
The idea of a concrete vessel seems counter-intuitive – how can such a thing float? – but float they did, and in fact more ferro-concrete barges would be constructed in the Second World War and see service into the post-war period.
The histories of Cretehawser and Cretestem are relatively briefly recorded, but seem to go adrift around the late 1930s and their circumstances during the war are also somewhat obscure. We know that Cretestem, 306 tons, was built by the Amble Ferro-Concrete Co. Ltd., launched on 31 October 1919, with machinery by McColl & Pollock of Sunderland, and registered in London on 13 December 1919. 
In 1920 Cretestem was still under the aegis of the Shipping Controller, changing hands to the Board of Trade in 1921, thence to the Crete Shipping Co. Ltd., London (Stelp and Leighton Ltd.) in 1922, in whose ownership she is still recorded in 1930. 
Cretehawser‘s story was similar, except that she was built by the Wear Concrete Building Co. Ltd. at Southwick, Sunderland, in 1919, with machinery by Central Marine Engine Works, West Hartlepool. 
In 1935 Creteboom, Cretehawser and Cretestem were to be broken up by the South Stockton Shipbreaking Co. The marine column in the Shields News noted somewhat disdainfully that ‘Dozens of these concrete tugs and barges were built at the end of the war and shortly afterwards. Although they suited the purpose at that time, they were never successful and the majority have since been disposed of for breaking up.’ A month later they were at R Duck’s on the Tees. 
Elsewhere they were much admired. A correspondent to the Edinburgh Evening News stated in 1940 that the Creteboom and Cretestem ‘both did service in the Baltic, where they encountered the arduous tests of frozen waters. The Cretestem also survived a head-on collision.’ The author continued that ‘they spent the last few years prior to 1934 in idleness in the Tyne, were examined in that year and found to be as strong and watertight as ever.’ 
Attitudes were just as divided as ever when an announcement was made that concrete ships would once more go into production in 1941, for their ‘saving in steel’ with a photograph of the Cretestem used to illustrate the concrete ships ‘of the last war’. 
Cretehawser‘s register was closed in 1936, and Cretestem‘s in 1937.  Thereafter the waters are somewhat muddied in the records and it is difficult to disentangle fact from fiction, or at least from stories that have gained traction. In 1937 a Tyneside newspaper correspondent wondered ‘if there are any of the war-time stone coffins still afloat? By stone coffins I refer to the concrete barges and tugs which were built in large numbers during the war period.’ The writer continued: ‘Many readers will recall the tugs Cretehawser, Cretestem, etc., which towed concrete barges from the Tyne to London . . . ‘ 
As stated above they weren’t actually very far away after being sold to the South Stockton Shipbreaking Co., but it does illustrate that they were a bit of a mystery locally. It is said variously that Cretehawser was gutted for possible use as an emergency breakwater in 1935, dismantled in 1936, and beached 1936 at South Hylton, and likewise Cretestem was dismantled in 1937. Elsewhere both vessels are recorded as having been bought by the River Wear Commissioners for breakwater use. They were then moored in the South Dock until required. 
Thereafter the story of the two ships diverges again. In other sources Cretehawser does not end up at South Hylton, where she now lies, until 1942 when she was damaged in a bombing raid, being towed up the River Wear and beached. 
The end for Cretestem is said to have come during a bombing raid on 24 May 1943, when, according to Lloyd’s War Losses, she was sunk by aircraft in Hendon Dock. Damage in Sunderland was extensive and there was significant loss of life. We know that there were a number of high explosive bombs dropped in and around Hendon Dock. Two 250kg high explosive bombs exploded in the Dock outside Monsanto works, and another in the works; a smaller 50kg bomb exploded west of Hudson Dock Bridge [sic] and another one ‘outside No.31 Coal Staith, Hendon Dock.’  The latter may be the coal staith shown alongside the Hendon Dock Swing Bridge that divided the Hendon Dock from the Hudson Dock to the north in historic Ordnance Survey mapping (1919-39) – the staith and bridge can be seen in this aerial photograph of 1928 on Britain from Above. (Check out the pins on the photograph.) ‘Hudson Dock Bridge’ in the bomb report could refer to the Gladstone Swing Bridge to the north of Hudson Dock but this seems unlikely as it is clearly marked as the latter on the OS map, so it must refer either to the Hendon Dock Swing Bridge between the two docks, or the bridge from Hudson Dock to the lock to the east and a direct outlet to the sea.
Whatever the ambiguities, it is clear that Hendon Dock received some damage.
What happened to Cretestem after that? Once again the story varies – her remains were lifted and dumped on the docks, or the wreck was towed out to sea.
We know from contemporary reports that ‘one vessel was sunk in the River and two in South Docks [i.e. Hudson and Hendon Docks] received damage.’  Cretestem is the only war loss and only ship sunk of which we are aware for 24 May 1943 and the days immediately before and after, so we cannot find any record of a ship sunk in the River Wear. So the Cretestem must be one of the two ships damaged in the docks: the date is correct and brings together the known damage in the docks with the Lloyd’s casualty report. Could it be that, as often happens with wreck reports, two details have been conflated and the ship that sank in the River Wear is also one of the two vessels which sank in the Docks, i.e. one of the two damaged vessels was in fact damaged so badly that she sank?
But why would the two ships be treated so differently after such a similar fate? Cretehawser towed up the Wear to be dumped, Cretestem dumped in or around the docks or out to sea? As we have seen, Cretehawser survived an air raid and remains indestructibly in the Wear 80 years on. Clearly a vessel sunk in a dock is an undesirable obstruction, so if this did indeed happen to Cretestem, she was almost certainly lifted.
Where she then went is a moot point. She would have had to be fairly intact to be towed out – a vessel in bits would not have been capable of being towed. In a war context, being towed out to sea seems perhaps less plausible, with the vessel towing her making what could be regarded as an unnecessary journey negotiating the convoys plying the swept War Channels, and the war perils lurking outside the Channels – not to mention the risk of causing an obstruction should the towed vessel suddenly sink, as hulks and submarines without their own motive power and damaged or beyond repair have a habit of doing.
Once again aerial photography comes to our aid. We cannot see Cretehawser and Cretestem in dock in RAF aerial photographs of 13 March 1941. However, they are identifiable side by side in RAF aerial photos of 22 October 1941 at the south-eastern end of the Hudson Dock, adjacent to the Hendon Dock Swing Bridge. They can be shown on photographic rectification to be the correct length and to share the distinctive characteristics of the Crete- ships. (Creteboom, also sold to the South Stockton Shipbreaking Co., was sold on out of the country in 1937, so is out of contention.) They are seen again in May 1942, almost exactly a year prior to the events of May 1943 (below).
They are both still together in the same position on 1 September 1942. There were both human and building casualties of an air raid in Hendon, Sunderland, on the night of 16-17 October 1942, but the bombs seem to have fallen slightly further west than the later raid, and the casualties were nowhere near as heavy. so it seems unlikely that Cretehawser was damaged in an air raid of 1942, as often stated, and towed away up the Wear then.
It seems likely, then, that it was the Hendon Dock Swing Bridge that was damaged on the night of 24 May 1943, and that Cretehawser and Cretestem were the two vessels that sank in the docks that night. Not quite ‘Hendon Dock’ as was stated in Lloyd’s, but not very far off at all.
So it was probably 1943, not 1942, when Cretehawser was towed away up the Wear. We can surmise that she was the less damaged of the two vessels, and Cretestem took the most impact from the blast, so Cretestem was probably the one immediately next to the bridge, with Cretehawser on the outside. Cretehawser was towed away, perhaps, to allow Cretestem to be dealt with.
We can see in the 1919-1939 mapping that there were travelling cranes around the seaward side of Hudson Dock. Was Cretestem then craned off and then perhaps dumped as infill for war blast damage? That sounds plausible – there is a long heritage of obsolete and damaged ships being used as the foundations of and infill for breakwaters, jetties and harbour walls. Perhaps this happened here.
We may never know – but at least aerial photography has shed new light on the story of Cretehawser and Cretestem.
This article would not have been possible without the invaluable help of my specialist colleague in the Historic England Archive, and Richard Lewis of The Crete Fleet blog. As ever, I am profoundly grateful for their kind assistance.
 Further discussion on the Crete– ships, their build and loss, in Cant, S 2013 England’s Shipwreck Heritage: from logboats to U-boats (Swindon: English Heritage); see also The Crete Fleet website
 Shields News, 9 May 1935, p4; Northern Daily Mail, 5 June 1935, p6
 Edinburgh Evening News, 19 February 1940, p4; information regarding Cretestem‘s service in the Baltic attributed by the writer of the letter to Fougner, N K 1922 Seagoing and Other Concrete Ships (London: Henry Frowde and Hodder & Stoughton) but probably sourced from some other publication, as not, apparently, in this text.
 Sunderland Echo and Shipping Gazette, 26 September 1941, p2
 Cretehawser: TNA BT 110/1015/8 Cretestem: TNA BT 110/1015/9
 Shields Gazette, 21 September 1937, p6
 Historic England Research Records, Cretehawser and Cretestem; “Sink me if you can!”
 Lloyd’s War Losses: the Second World War 3 September 1939 – 14 August 1945 Vol.1 p678; Ripley R & Pears B 2011 North-East Diary 1939-1945 Incidents 23rd/24th May 1943 to 9th September 1943
 North-East Diary 1939-1945 Incidents 23rd/24th May 1943 to 9th September 1943