World War II bombing decoy on Fobbing Marshes, 1.11km and 1.15km north west of Oozedam

Reasons for Designation

World War II saw the emergence of aerial bombardment as a decisive instrument of warfare, and to counter this threat, the United Kingdom maintained a flexible and diverse mechanism of air defence throughout the war. This included the early warning of approaching aircraft, through radar and visual detection, and the local defence of towns, cities and other vulnerable points using anti-aircraft gunnery and balloon barrages. But less conspicuously, many potential targets were shadowed by decoys - dummy structures, lighting displays and fires - designed to draw enemy bombs from the intended points of attack. Britain's decoy programme began in January 1940 and developed into a complex deception strategy, using four main methods: day and night dummy aerodromes (`K' and `Q' sites); diversionary fires (`QF' sites and `Starfish'); simulated urban lighting (`QL' sites); and dummy factories and buildings. In all, some 839 decoys are recorded for England in official records, built on 602 sites (some sites containing decoys of more than one type). This makes up the greater proportion of the c.1000 decoys recorded for the United Kingdom. The programme represented a large investment of time and resources. Apart from construction costs, several thousand men were employed in operating decoys, the fortunes of which were closely tied to the wartime targets they served. The decoys were often successful, drawing many attacks otherwise destined for towns, cities and aerodromes. They saved many lives. Urban decoy fires were known as `SF', `Special Fires' and `Starfish', to distinguish them from the smaller `QF' installations. Each town was protected by a cluster of these decoys, the most technically sophisticated of all the types, with each Starfish replicating the fire effects an enemy aircrew would expect to see when their target had been successfully set alight. The decoys included variation in fire type, duration of burning and speed of ignition. In a permanent Starfish all fire types were used, set in discrete areas defined by firebreak trenches and controlled from a remote shelter. The whole array was linked by a network of metalled access roads. `Temporary Starfish' (all built in 1942 to counter the threat from the so-called Baedeker raids against historic towns and cities) only had basket fires. In all, 228 decoys with a Starfish component are recorded in England, 37 of which were `Temporary Starfish', and the rest `Permanent'. The Permanent sites were located mostly in central England, close to the urban and industrial targets they were intended to protect; temporary sites, like the Baedeker targets they were protecting, were confined to southern and eastern England. QF sites were first provided for the night protection of RAF airfields, but from August 1941 their role was extended to protect urban centres. Although similar to Starfish, they differed in being considerably smaller, using a limited range of fire types and being sited for the local protection of specific vulnerable points rather than whole cities or conurbations. These new QF sites of 1941-2 fell into four groups, for the protection of: urban and industrial targets (the `Civil Series', located mostly in the west Midlands, north-west and in the Middlesbrough area); Royal Navy sites (these were few in number and sited to protect coastal bases); Army sites, to protect ordnance factories or military installations (these existed in a sparse belt running from central southern England into the west Midlands); and oil installations and tank farms (the `Oil QF' sites). In all, only about 100 QF sites were operational in England. Very little now survives of any of these decoys, most having been cleared after the war. All sites with significant surviving remains will be considered of national importance, as will those where a well-preserved night shelter has been identified.

The survival of major components of the World War II bombing decoy documented in wartime records as `Shell Haven, Fobbing' is of great importance to the study of bombing decoy design. The Oil QF decoy is one of an original deployment of only two such sites in Essex (the other being `Thames Haven, Stanford-le-Hope') whose purpose was to simulate the results of a successful night-time bombing raid on an oil refinery. Beset by development problems and expensive oil usage, only twelve Oil QFs were constructed throughout Britain. The Fobbing night shelter is a good example of this rare type of structure, and the survival of associated storage bays adds to the overall importance of the site.

Details

The monument lies in an area of open marshland known as Fobbing Marshes, to the north of the Shell Haven Oil Refinery which occupies a large site on the north bank of the River Thames. It is in two areas of protection.

Documented in wartime records as `Shell Haven, Fobbing' the monument is the night shelter and oil storage bay of a World War II Oil QF (diversionary fire) decoy designed to protect the Shell Haven oil refinery. At the peak of its operation the decoy would have had many burning pools of oil and simulated ring fires from burning oil storage tanks; these would have been ignited electrically from the night shelter, situated some distance away, which also housed the generator and decoy manning personnel. Although nothing remains of the arrangement of decoy fires, the night shelter and the walls of an oil storage facility remain. The night shelter is built of concrete; it is 6m long by 3.2m wide, aligned north-south and has a single sloping entrance on its northern side. Inside are two rooms: the southernmost is the Operations Room, with the smaller Engine Room to its north. The Operations Room measures 2.9m by 2.5m and has an escape hatch in the roof at its southern end with steel rungs leading up to it. Two steel connection pipes which match up with pipework on the outside, probably contained the wiring terminals for the electrical ignition of the decoy devices. The Engine Room measures 2.5m by 2.3m and would have contained the generator (no longer present), bolted onto a low concrete base which still survives.

Approximately 17m to the west of the night shelter, on heavy concrete foundations, are four parallel walls each 7m long by 1.3m high, aligned east-west. With railway sleepers formerly bridging the gaps, these walls are thought to have functioned as six storage bays for the drums of oil necessary for the operation of the site.

War Office documents relating to the equipment and manning of the bombing decoy show that it was operational in August 1941 (the earliest reference to it dated 1st August) and was certainly in use in March 1942 (latest written reference); although no further specific documentary references can be found it may have continued in use through to the end of the war.

All modern fencelines are excluded from the scheduling, although the ground beneath them is included.

MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 2 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

32445

Legacy System:

RSM

Sources

Books and journals
Dobinson, C S, Twentieth Century Fortifications in England: Volume 3. Bombing Decoys of WWII, (1996), 141-2
Dobinson, C S, Twentieth Century Fortifications in England: Volume 3. Bombing Decoys of WWII, (1996), 116-8

Other
7 colour prints in ESMR, Nash, F, Untitled, (1999)
Tyler, S, MPP Film , (2000)
Tyler, S, MPP Film , (2000)
7 unreferenced frames in the ESMR, Nash, F, Untitled, (1999)

End of official list entry

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