Cold War defence boom, Pig's Bay, Shoeburyness

Reasons for Designation

The archaeological remains of the Cold War are the physical manifestation of the global division between capitalism and communism that shaped the history of the late 20th century. The defensive boom at Shoeburyness provides a graphic representation of military thinking in the early period of this conflict, when defence strategy drew much of its inspiration from the experience of World War II.

The original wartime boom was designed to prevent enemy vessels from entering the Thames and attacking anchored shipping. It served to constrict the channel and as a mounting point for anti-aircraft guns and searchlights providing some defence against aerial attack along the Thames. By 1950-53, when Admiralty plans record the construction of the replacement boom, the nature of the threat was very different. Britain's main concern, heightened by political tensions arising from the Korean War, was the Soviet Union's ability to attack major urban centres with manned turboprop bombers carrying atomic bombs.

The replacement boom would have served little purpose in such an eventuality and, like the retained `Igloo' system of anti-aircraft guns in Kent and Essex, seems to have formed part of an increasingly outmoded defence strategy based on wartime precedents rather than the emerging threat. By the mid 1950s advancing technology, in the form of fast jet bombers, the hydrogen bomb and the capability of long-range rockets rendered the boom system obsolete and heralded its eventual, partial, demolition.

Although many defensive barriers across estuaries and harbours are known from World War II (and indeed earlier periods), the Shoeburyness boom is the only example known to exist, or to have been built, during the Cold War era. The surviving section of this unique structure remains well-preserved and serves as a significant illustration of Britain's early attempts to formulate effective defence measures in the face of rapid technological development.

Details

The monument includes the remaining part of a naval boom, constructed across the Thames estuary between Shoeburyness and Sheerness in order to control the movement of shipping in the early years of the Cold War.

The surviving section of the boom is formed of two parallel rows of tall off-set concrete pilings, linked by angle-iron strapping to form an undecked pier extending some 2.01km from the north bank of the estuary. The landward end of the pier is marked by the heads of piles buried by sand near Blackgate Road, Shoeburyness, between the former Royal Artillery barracks and the military firing ranges. From here it extends in a south easterly direction via three straight runs of pilings and two shallow angles, crossing sand banks and mud flats to reach the mean low water mark at the south end of Maplin Sands.

The boom was built in the early 1950s to replace a World War II pier of similar purpose that stood some 15m-60m to the north east, of which nothing remains. Like its predecessor, the replacement boom once extended as far as the deep water shipping channel. A matching structure continued south of the channel to Sheerness on the opposite side of the estuary. It was intended that moored vessels would occupy the gap between the two piers. However, the rapid pace of technological change in the early stages of the Cold War soon made this form of defence redundant. The boom was subsequently demolished in the 1960s leaving only the truncated northern arm to mark its former presence. This surviving section is almost completely intact, with only a short gap in the third run of pilings and some limited loss of piles towards the outer end of the second run. It is believed to be unique.

The following items are excluded from the scheduling: all fixtures and fittings relating to the modern shipping navigation light at the seaward end of the pier and all warning notices, mooring bollards and modern access walkways and ladders. The Cold War structures beneath them or to which they are attached are, however, included.

MAP EXTRACT The site of the monument is shown on the attached map extract.

Legacy

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

Legacy System number:

35502

Legacy System:

RSM

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