NHER 52492 (Monument record) - World War Two Anti-Aircraft Ordnance Depot for Norwich

February 2010. Norfolk NMP.
A large World War Two military site is visible as buildings, structures, earthworks and related features on aerial photographs (S1)-(S6), centred at TG 2381 0542. It has been identified by Roger Thomas of English Heritage (who has also supplied the information detailed below) as almost certainly the site of the Anti-Aircraft Ordnance Depot (AAOD) for the Norwich Gun Defended Area (GDA). It was almost certainly constructed in the period circa 1937-8, as part of the pre-war expansion of Britain’s anti-aircraft defences. It is not depicted on the 1938 Ordnance Survey map of the area (S7), but it may have been omitted deliberately due to its military sensitivity. It would have been used for the storage and maintenance of anti-aircraft guns for the Norwich Gun Defended Area. There is clear evidence of considerable use of the site in 1942 (S1), but by September 1945 (S2) it appears to have already been subject to some disuse and clearance. More recent aerial photographs indicate that while few traces of the outlying elements appear to survive, in the main technical area, now occupied by a factory, many of the World War Two structures and buildings may still be in use. These include the main 6-bay workshop which appears to be the principal factory building. The site has not been mapped in detail by the NMP; only a selection of the structures and buildings mentioned specifically in the text below have been mapped.
The main technical part of the site is visible at TG 2381 0540, on the area subsequently occupied by the factory. The main workshop and storage building, seemingly still in use today, is formed of 6 bays, and has numerous vehicles parked outside. To the north, at the entrance to the site, a surviving house – The Bungalow – may have been used as a guardroom and/or a caretaker’s house; that the garden was being cultivated in 1945 (S2) suggests it was being used as a house (by this date at least), while a camouflaged curved-profile hut on the other side of the entranceway (at TG 2382 0546) was probably used as the guardroom. In the northwest corner of this part of the site (at TG 2375 0546), a pitched-roof hut was probably the motor transport section garage; in the southwest corner (at TG 2377 0534) is the maintenance garage, which may also still survive, and immediately to its south is an extension in the form of a possible, unusually long, Romney hut. Various other buildings, huts and structures are visible in the technical area, including a probable electricity substation (protected by a blast wall) at TG 2384 0541, static water tanks at TG 2380 0548 and TG 2379 0534, and probable below-ground air raid shelters (not mapped) at TG 2385 0534 and TG 2384 0539.
In the field to the north (centred around TG 2385 0553) the accommodation site associated with the depot is visible. Comparison of the photographs from 1942 and 1945 show that this area was enlarged during the second half of the war, and evidence of gardening or horticulture in the northwest corner of the site may indicate that it was used to house prisoners of war in the later stages (or after the end) of the war. The accommodation was made up of a variety of huts and structures (none have been mapped). A large U-profile hut at TG 2384 0554, together with adjacent structures, housed the cookhouse and dining hall; a long U-profiled hut at TG 2389 0554 was the headquarters; and a group of six huts connected by covered passageways, known as a ‘spider’ (at TG 2390 0550), would have provided accommodation. Other structures include a coal store (at TG 2385 0550) and a weapons pit surrounded by a high wall of sandbags (at TG 2392 0551). The accommodation area was bounded to the north and east by a fence/hedge (depicted by NMP), perhaps reinforced with barbed wire. Further to the east, an area of clear but uncultivated ground may also have formed part of the site, although this is not entirely certain and what it was used for is unclear.
In the field to the west (on the other side of Old Stoke Road), earthworks, structures and areas of disturbed ground are likely to relate to sewage treatment works associated with the accommodation site. Patches of disturbed ground or possibly small structures or areas of concrete are visible at TG 2373 0552, but their purpose is uncertain and they have been mapped only by extent. To the south, at TG 2373 0550, is a concrete pad or sunken structure, surrounded by a fence conjoined with a small square hut. The purpose of this group of features is again unclear. From it leads a narrow ditch, which heads westwards in a series of angled segments before turning northwards. At its northern end (at TG 2368 0554) one would expect to find a circular filtration tank, pit or bed (Roger Thomas, verbal communication), but there is no sign of one. To the west (at TG 2366 0554) are a group of three pits which are almost certainly associated with whatever sewage system was in place. On photographs taken in 1946 (S3)-(S4) the ditch (presumably some sort of drain or channel) appears to extend (or to have been extended) a considerable distance to the north, and by 1951 (S5) the pits had been cleared or re-cut, indicating their continued use in the post-war period.
In the field to the southwest of the technical site (at TG 2371 0526) is a small sports field, perhaps used for hockey or five-a-side football, both popular with the Navy and female personnel. Further to the west and beyond the limits of the site (at TG 2368 0528) a small hut or structure appears to be in agricultural use and consequently has not been mapped or included in the site, but a military origin for it (not necessarily in the same location) cannot be ruled out. A slit trench 180m to the southeast of the site (NHER 52480) may be an associated defence.
S. Tremlett (NMP), 4 February 2010.