Royal Observer Corps Monitoring Post

Summary

Royal Observer Corps (ROC) monitoring post, 1961. Standard design. Buried structure constructed from concrete.

Reasons for Designation

The former Royal Observer Corps monitoring post on Keelby Road, one of a network of subterranean posts designed to monitor radioactive fallout following a nuclear attack, is designated at Grade II for the following principal reasons:
* Architectural Interest: An example of a standard design that is an architectural representation of the threat of nuclear attack during the Cold War.
* Historical interest: The juxtaposition of the ROC Post with the earlier Second World War Heavy Anti-Aircraft gun site reflects the changing response to the threat of aerial attack in the C20.
* Intactness: The building survives structurally intact with the rare survival of internal fittings.

History

The Royal Observer Corps (ROC) was a civilian service, mainly staffed by volunteers. Its original role was to visually spot enemy aircraft, but in 1957 it became part of the newly formed United Kingdom Warning and Monitoring Organisation (UKWMO), charged with the task of reporting nuclear explosions and the monitoring of the resultant spread of radioactive fallout in the event of nuclear attack. This was facilitated by the construction of a national network of 1518 monitoring posts (1026 being in England) organised into clusters of 3-4 posts which then reported to regional Group Headquarters. In 1968 the number of maintained posts was halved and in 1991, with the end of the Cold War, the service was stood down and the posts closed.

Construction of the system of monitoring posts began in the late 1950s and was largely complete by 1965. The posts had three main tasks: to confirm that a nuclear attack had taken place and its location; to estimate its power; and to monitor the passage of radioactive fallout. They were built to a standard design to accommodate a staff of three and to be self sufficient for 21 days. The posts were buried below the ground surface and covered with an additional compacted earth mound designed to provide protection from blast and heat, and to reduce radiation penetration.

The ROC monitoring post on Keelby Road was built and opened in 1961 at the site of a former Second World War Heavy Anti-Aircraft (HAA) gun site. It was known as the Roxton ROC post or more formally as post 20/V2 from September 1963 and then 15/B2 from October 1968 (Dobinson, 2000 p252). The ROC post continued to be operational until September 1991. It was surveyed in 1999 and found to retain most of its internal features including furniture (Subterranea Britannica 2001). It is believed to have remained undisturbed ever since.

Details

ROC and UKWMO monitoring post, standard design of 1956 by the Air Ministry Works Department, this example built 1961.

MATERIALS
Reinforced concrete with compacted earth covering.

EXTERIOR
Appears as a rectangular, flat topped vegetation covered mound with a raised entrance hatch towards one end and a smaller, raised air vent towards the other end. Between these two openings, protruding through the mound, are two metal pipes that were the mountings for monitoring equipment: The one closest to the hatch being for the probe for the Fixed Survey Meter (for measuring radiation); the other for the baffle plates of the Bomb Power Indicator. The mounting for the Ground Zero Indicator (a pinhole camera device for detecting the direction and altitude of nuclear explosions) is adjacent to the entrance hatch.

INTERIOR
The 4.6m deep entrance ladder-shaft has a drainage sump at its base and a hand operated pump. It gives access to a small closet for a chemical toilet and to the monitoring room which measures 4.6m by 2.3m. In 1999 it was recorded that the post retained furniture including fitted shelving and a table.

MAPPING NOTE
The monitoring post is not mapped by the Ordnance Survey. The map depiction of the List Entry is for general identification purposes and does not attempt to accurately map the exact extent of the structure with its earth mound (which is smaller than the area depicted).

Sources

Books and journals
Dobinson, C, Twentieth Century Fortifications in England Volume 11 and appendices: The Cold War, (1998)
Cocroft, W D, Cold War Monuments: An Assessment by the Monuments Protection Programme, (2001)
Lowry, B (ed), Twentieth Century defences in Britain. An introductory guide, (1995)

Websites
Subterranea Britannica, accessed from http://www.subbrit.org.uk/cgi-bin/webdata_roc.pl?fid=988309552.043003&query=pagenum%3D5%26cgifunction%3DSearch%26County%3DLincolnshire&cgifunction=form

End of official list entry

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