ROF Dunham on the Hill

Phil Pritchard


The Royal Ordnance Factory Dunham was in the village of Dunham on the Hill, near Helsby in Cheshire. Built during WWII, it was the store for all of the explosives shipped in from Canada under the Mutual Aid Act. They were the sole source of explosives for the Rhydymwyn Valley operation.

Royal Ordnance Factories – A Summary

The title "Royal Ordnance Factories" was the collective name of the UK Government’s munitions works, during, and after WW2. Until privatisation, they fell under the MoS (Ministry of Supply), and then latterly the MoD (Ministry of Defence).

During WW1, the equivalent was the NEF (National Explosive Factory) and the NFF (National Filling Factory).

Some ROF’s were built and run by the government, others were built and owned by ICI, but were not considered to be part of the MoS ROF organisation, and were not called ROFs. Other MoS funded factories were managed by ICI, and were known as "Agency Factories". Other ROF Filling Factories, especially later in the war, were managed in a similar manner to the "Agency Factories", but by organisations not normally connected with armaments.

During WW2, new ROFs were constructed, but usually in areas that were considered "safe", i.e. north-west of a line drawn from Bristol, to Weston-super-Mare, to Haltwhistle (Northumberland) and then to Linlithgow (west of Edinburgh). There were exceptions to this geographical rule.

The three main types of ROF were:

These three types were also the biggest, as the buildings had to be widely spaced.

The other three types were:

They tended to be self-contained, with regards to power, hostels, domestic arrangements, well being, and accommodation. The security was maintained by the "Ministry of Defence Police".

Some were designated "temporary", i.e. only extant until the end of WW2, and others were "permanent" – which continued in use after WW2, these WW2 survivors eventually succumbed to a wide range of fates, the later surviving ones becoming part of QinetQ.

This particular ROF depot is often marked on period maps as "B.E.", i.e. a "Bulk Explosive" store.

Introduction to ROF Dunham-on-the-Hill

This is a puzzling site. It is easily visible from the M56, travelling in both directions. The most frequent view is of the two brick "sheds" from the M56, travelling past the Helsby turnoff towards north Wales.

They are obviously too big to be normal agricultural barns, one end is obviously intended to be driven through, but at the same time is far too big for even a modern heavy goods vehicle. They look like a typical WW2 structure, but not quite. After driving past several times, it is then obvious that there are other "sheds", scattered around the fields. Some are not quite the same, some are the same, some have earth banks, some do not, some have standing brick walls, some do not, some standing walls have diagonal markings, others not.

The examination of aerial photography websites reveals a considerable number (28) of the "sheds", and visual hints of tracks connecting them. They look military, and they start looking like an ammunitions storage area.

This map shows the internal layout, perimeter fence line, the railway line, the numbering of the sheds & magazines,
and the route of the modern M56 motorway.

Casual discussions with local people suggested that the site was a munition dump, built by Italian PoW’s in WW1, that it was owned by Cheshire CC, and that it was currently used for agricultural purposes. One good source stated that earth banks were essentially clay, and were taken away and used to line the nearby Cheshire CC Gowy landfill site.

The site appeared to be very large, but with very little information available, and even to the extent that the name was missing.

Internet searches revealed pieces of information, but very little. The key fact, discovered in a Signal Box directory, was that the main line signal box (Dunham-on-the-Hill No.2) was a Midland Railway ARP (Air Raid Precaution) design, which was a WW2 design, which was designed to be operational even after a close miss from an exploding Luftwaffe bomb. The signal box looks substantial, which is probably why it is still in existence.

An Internet search for the signal box came up with a reference to a "Railway Modeller" magazine article, published in December 1990. The article was written by a member of the Merseyside Model Railway Club. The article had few words about the ROF site, and was essentially concerned with the signal box, which was of historical interest in railway circles.

Despite the main function of the ROFs being the manufacture of munitions, "ROF DotH" was to be different. It was not actually involved in manufacturing at all. It was primarily for the storage and distribution of explosives that were then to be used in other ROF establishments as fillings for shells and munitions.

The DotH site was built on a site requisitioned in 1941 for the war effort, on behalf of the Ministry of Supply (MoS) under the "Emergency Powers (Defence) Act 1939".

Construction of the site started on the 7th June 1941, completed by the 5th August, and was open for use on the 11th August 1941.The supplies were initially received by the nearby, and already existing Dunham Hill Station goods yard. The LMS railway was given a special license for the right of access.

Upon cessation of hostilities, the depot was retained for food storage, eventually ending up responsible to the Ministry of Agriculture, Fisheries and Food (MAFF). This role ceased in September 1985, and in 1990, it was disposed of into the private sector. When used in this latter role, it was known as a "Buffer Depot".

The stored food included large tins of baked beans, margarine, butter, cocoa powder and large tins of dried milk. Local information is that the food, after closure was to be stored in "old mine workings", and was removed by road vehicles. Some of the food was certainly transported by road to a company "Lovell & Christmas". As a "Buffer Depot", the food was regularly replaced. The stored food initially included tins of Corned Beef, but a batch, after it had been replaced in the depot was put onto to the open market, was blamed for an outbreak of Typhoid, the storage of Corned Beef was ceased. There were very few workers on the Buffer Depot site, mainly warehousemen.

There are also recollections of the depot being used for the storage of machine gun bullets, and other items that were manufactured at ROF Capenhurst, which was only a small number of miles away, presumably before Capenhurst took on its "nuclear" role.

The Role of ROF DotH in WW2

The main role of DotH during WW2 was for the storage of explosives, but there is a significant story behind this role.

Explosives were shipped into the Mersey ports, for use during the war. The geographical position of DotH was very appropriate, as it was in a very good strategic position on the railway lines in the area. The site was not chosen by chance. It was in a position to receive the explosives & munitions, and to then store them for further distribution to other ROF factories and filling depots, the workers recollect shipments from Canada, and distribution to ROFs at Fazakerley, Rhydymwyn, Chorley and Chelford. The shipments to Fazakerley would suggest that the shipments were into Birkenhead Docks, rather than Liverpool Docks.

The received explosives were mainly Neonite, Cordite and TNT; they arrived packed into cloth bags, which were in turn packed into wooden crates and boxes. There were also substantial quantities of ammunition boxes and cartridge cases, as well as boxes of "yellow powder".

This distribution activity, made the local railway line very important to the war effort. There are some local defensive weak spots to the railway, namely a cutting, and the Frodsham Viaduct, which crosses a wide valley over the River Weaver navigation. This is easily observed from the M56 Frodsham Viaduct.

A road bridge across the cutting was protected by a pillbox, which still remains to this day in the corner of a private garden on Wood lane. The viaduct itself was protected from air attack by two Heavy Anti Aircraft (HAA) gun sites, each with 4 guns. They are situated off Aston Lane, and Townfield Lane. The example on Aston Lane is still in excellent condition and a credit to the owners. The only remains of the Townfield Lane site are pieces of broken up concrete used in the gardens, walls and rockeries of local housing.


The building of ROF DotH was subject to the usual WW2 secrecy, and misinformation that abounded. One quantity surveyor that worked on the project stated that it was an "Empty Component Store", and that it was to be associated with Risley ROF No.6, and the nearby Hooton ROF No.10 (still known locally as Roften). He believed it to be just a storage depot, but did query as to why the buildings were so dispersed, and as to why some had earth banks surrounding them, but in those days, it was not the "done" thing to ask questions.

ROF DotH was built at the start of WW2, on a flat, marshy area adjacent to the Mersey Estuary. It is between the Hooton to Helsby, & Chester to Helsby railway lines. It was intended for the bulk storage of explosives, and as such, also had to be remote from centres of population.

The site is roughly about a mile square, but has an irregular perimeter of between four and five miles. The storage of the bulk explosives was in a number of brick and steel built "sheds", 28 in total, which included 10 "sheds" which were designated as "magazines", these were surrounded by earth and clay blast mounds, with a brick blast wall at the rail entrance as it was a weakness. They are also very well landscaped into the scenery.

The earthworks that were used as blast barriers around the magazines were constructed using a narrow gauge railway, using a petrol-engined locomotive, which pushed tipper trucks around the site. The driver sat sideways in the locomotive.

The main construction contractors were a company called "Demolition and Construction Ltd.".

Details of the "Sheds" and Magazines

There were 28 main storage "sheds", 10 of which were designated as "magazines", and were located in the centre of the site. The term "magazine" was used within ROF sites, but many were much smaller, and some not even rail connected. The correct term for the Traversed Sheds (Earth Banked Buildings) is Explosives Store Houses (ESH). These one-sided ESH buildings are of the same design as could be found at CAD Bramley in Hampshire, and at CAD Kineton in Warwickshire. Most of the examples at CAD Kineton were demolished in the mid 70's to 80's to make way for a new build depot, leaving only 3 remaining. CAD Nesscliffe was a mix of this one sided ESH, and a centre access design which was also earth covered.

Some of the ESH buildings have had the earth mound removed by Cheshire CC, and taken away to line the nearby Gowy land fill site. These are obvious, as they usually have a substantial brick blast wall at the point in the bank where the railway track would enter, where the mound has been removed, it usually leaves a diagonal line on the blast wall. Some of the ESH buildings had a complex shaped earth mound, presumably as some attempt at camouflage / landscaping.

A Magazine that has had the surrounding earth mound removed – note the diagonal earth line on the brick blast wall to the right

The sheds are approx. 35 metres long, and 12 metres wide (measured at the "storage" section), and 15 metres wide at the loading / unloading dock end. The engine shed is slightly smaller at 19 metres by 6 metres.

The buildings were constructed of a lightweight steel framework, filled in with a single layer of common bricks. Each building had a small "sentry" box, on the storage side of the entrance, nearby was usually a concrete pipe water butt, with asbestos guttering and downpipes. The roof was made of very lightweight concrete sections, and covered in asphalt. There were lines glass lights set into the brickwork at the top of the walls. Each shed had a steel ladder for access to the roof.
The sheds did not contain any electrical wiring, lights or fittings, obviously because of the explosion and fire risk.


The security was the responsibility of the "Ministry of Defence Police", but there are also recollections of a detachment of the Home Guard being stationed there, and being accommodated in huts for the duration.

The whole site was surrounded by a single line of seven foot high chain link fencing with concrete posts seven feet apart, and the usual barbed wire on top. Significant lengths of the fence still remain. There were 4 security men per shift, and a gateman.

Patrols were usually done by two security staff (who worked a three shift system), and Alsatian dogs. There were two types of passes, which had to be produced for entry, additionally; workers were searched at the gates for matches and cigarette lighters. The two types of passes were for one for the workers, and another for the farmers, presumably attending to the cattle. At times, during WW2, there were as many as 8 gates used for access onto the site, each gate had a sentry box, and guards, when in use.

No doubt, in an effort to keep up the war effort, and to keep the grass down, cattle (both for milk and beef) were allowed into the site for grazing.

Domestic and Working Arrangements

The local workers travelled to the site by either foot, cycle or by rail services to Dunham Hill Station, which was adjacent to the ROF site.

There was a hostel on the site during WW2, but most of the people accommodated in the hostel worked at ROF Capenhurst. The hostel is now the site of a traveller’s encampment. The hostel area also included some bungalows, as well as separate Nissen huts for men and women. There was also a canteen on-site. Helsby Grammar School was also used as a hostel during WW2 for DotH workers, in addition to another hostel at Lowton St Marys, near Wigan.

The total number of workers was around fifty, including a substantial number of Irish, Welsh and Geordies. The workforce had a regular skilled core of local people, and a varying number of transient workers. On some occasions, men were transferred by rail between DotH, Beeston fuel dump, Mickle Trafford ammunition dump and Ince petrol dump.

The transport around the site was primarily by the before mentioned "tram", cycles were also used extensively. During the war years, there were two shifts, 6-2 and 2-10.

Railways – General

The storage "sheds" were all rail connected by standard gauge track work, laid on clinker and ash ballast, and mostly bolted onto concrete railway sleepers, except (as is usual) underneath the points. The points were hand switched. There were around five miles of track, and 30 sets of points. Each "shed" had its own siding, and buffer stop. The rail was flat bottomed, with a height of about 5 inches, which would have been 75 pounds weight per yard.

There was a main line rail connection (to the L.N.W. & G.W. Joint Railway), and sidings, access to which was controlled by a L.M.S. "ARP" signal box, which still exists. The sidings were over half of a mile long, with the longest having a capacity of 60 wagons.

This map shows the main line railway, sidings, signal box locations and the connection to the internal rail network, as well as the shed and magazine numbering.

The explosives arrived by rail, the wagons were stored in the sidings until being brought into the site by the MoS 4-wheeled diesel shunters, "match" wagons were inserted between the goods wagons and the locomotive, then they were shunted (usually in groups of four) to the storage sheds, where they were unloaded, one at a time under cover.

For safety reasons, the "match" wagon was to prevent the diesel shunter having to enter the storage shed, and the explosives were manually unloaded onto wooden supports, i.e. there was no motorised assistance. Trains on the mainline railway system used 'Buffer Wagons' of Inert Stores or two empty goods wagons to create a spacer between the locomotive and the wagons carrying explosives.

Both Saturday and Sunday were allocated to maintenance work on the shunters. There were two small loco sheds on the site, one for maintenance with a pit, the other for storage only. The maintenance shed with the pit was the one nearest to the main line sidings; the storage shed was further into the site.

The shunters were ostensibly allocated to the Chester 6A locomotive shed for heavy maintenance, with the drivers being employed by the MoD. One worker recalls starting employment in the sheds, then becoming the Foreman, having to drive the locos when required, and eventually becoming the full time driver when the usual driver retired. However, he moved on to become a watchman, working shifts because the pay was better.

There were 2 gangs in the engine sheds up to 1949, reducing to 9 workers by 1959. The site traffic was very busy, until 1944, when the ROF work started to decline. The site had an underground fuel dump, holding diesel for the shunters, and petrol for road vehicles and the personnel "tram".

Not directly associated with the site, but of local interest was an account of a "runaway" Stanier Class 8 locomotive from the shed at Alvanley; it was eventually derailed at Freshmeadows Lane, just in advance of Helsby Junction. However, the locomotive took around a fortnight to be recovered from the embankment, causing severe disruptions to local traffic.

Railways – Signal Box

To provide control of access into the site, a new signal box was required. This was named "Dunham-on-the-Hill No.2". It was built to "Air Raid Precautions" specification, usually abbreviated to ARP. To meet the specification, it had to resist damage from direct 1 Kilogram incendiary bomb hits, and the blast from nearby large bombs. There were only small amounts of wood used in the construction, and a large amount of standardised pre-cast concrete components. There were very few openings in the walls. The heating was by oil lamps, and drinking water had to be transported there in containers, neither of which was unusual at the time. The roof was a 12 inches thick reinforced concrete slab.

Sketches of Dunham No. 2 ARP Signal Box.

The contractor was "Cartwright Massey" of Moore, Warrington, and it was built in 1942 at the same time as the construction of the depot. This particular example is known (by the "Signalling Record Society") as a LMS ARP Type-11. There were over 50 examples built by the LMS. After the war had ended, there was little signalling activity, and it was subject to a temporary closure in 1946, kept in a maintained condition, followed by complete closure in 1949, however, the temporary speed restriction notice issued at the time of closure refers to closure in 1951

It controlled access to the sidings at the east end, and had 20 levers, but only 16 were used. There was another ARP signal box, "Dunham-on-the-Hill No.1" at the west end of the sidings, built at the same time as No.2. No.1 replaced an 1873 signal box that was too small as a consequence of opening the DotH depot. The No.1 had 40 signal levers, but was closed in 1969. Between the closure of No.2, and the closure of No.1, No.1 was renamed to simply "Dunham Hill".

Reputedly, and by definition, the ARP signal boxes are difficult to demolish, despite this, there are few examples remaining.

Railways – Locomotives

There were usually at least two shunting locomotives on the site, one in use, and the other on "standby" as a spare. Locomotives usually arrived on site by road, and were unloaded sideways by draglines and jacks, onto the tracks.

The Fowlers were reputed to have an awkward "gated" gear change, and had a conventional starting handle. The Andrew Barclay "Kent" locomotive had pneumatically operated controls, and required a charged up air tank for starting. On one occasion, the air cylinder lost pressure; consequently the locomotive had to be started by means of a "push" start from a main line loco.

All locomotives wore a dark green livery. They had water exhaust traps, so that sparks could not be emitted from the exhaust, for obvious safety reasons whilst handling explosives.

There was also a "tram" type of rail vehicle, for transporting workers around the site, it featured a roof, and no sides, but was capable of carrying 6 people (probably not in comfort). It was driven by a petrol engine, and had a friction drive. The driver was always one of the loco men on the roster. However, the "tram" met with an accident where it was crushed, and was subsequently replaced. There was also a trailer that was used with the "tram" for carrying small equipment.

Locomotive Details

There were a number of locomotives recognised at various times as being allocated on-site. The normal arrangement was for local numbering schemes; however in 1961 the War Department (WD) assumed responsibility for locomotives at ROF locations, the ROF locomotives were then re-numbered into the WD scheme. The locomotives are tabulated below:

Dunham No. 1

  • 0-4-0 150hp, 29 tons Diesel Mechanical Shunter
  • Manufactured by John Fowler (Leeds), Works No. 22978 in 1942
  • Ex-factory 13/06/1942, delivered new to DotH on 15/06/1942. However, the track was not ready, and there was no locomotive shed. The locomotive was used for driver training, and entered service 06/07/1942.
  • Sold to T. W. Ward, Grays, Essex circa 1953, and overhauled June 1954.
  • Sold to Joseph Boam Ltd., Middleton Towers Sand Pits, Norfolk circa 1963
  • Withdrawn circa 1967 as "beyond economic repair"
  • Disposed of circa 1969 – assumed to be "scrapped"


Dunham No. 2

  • 0-4-0 150hp, 29 tons Diesel Mechanical Shunter
  • Manufactured by John Fowler (Leeds), Works No. 22985 in 1942
  • Ex-factory 24/09/1942, delivered new to DotH on 25/09/1942
  • Sold to a dealer, Abelson at Sheldon November 1950
  • Sold Furness Shipbuilding Co. Ltd., Haverton Hill, County Durham by a dealer G. E. Simm Ltd., circa 1952
  • Scrapped circa 1959, the frames were retained as a "bogie truck".


Dunham No. 3

  • 0-4-0 150hp, 29 tons Diesel Mechanical Shunter
  • Manufactured by John Fowler (Leeds), Works No. 22987 in 1942
  • Delivered new to DotH October 1942
  • Moved to ROF Ulnes Walton 29/11/1042


Dunham No. 2 "Kent"

  • 0-4-0 150hp, Diesel Mechanical Shunter
  • Manufactured by Andrew Barclay, Works No. 331
  • Delivered new to Royal Arsenal, Woolwich 13/06/1938
  • Moved to DotH February 1953 after repairs at FC Hibbard & Co. Ltd, Park Royal
  • Moved to ROF Chelford, Cheshire 27/04/1961
  • Moved to WD Bicester workshops, Oxon, re-numbered as WD 861, 16/01/1964
  • Moved to MoD Eskmeals - Proof and Experimental Establishment, Cumberland, 06/11/1964, and renumbered WD 241 under the 1968 re-numbering scheme.
  • Sold to Walsh and Dearden, Darwen, Lancashire 09/06/1977, and scrapped between March 1980 and November 1980.

Dunham locomotive No. 2 "Kent"


ROF No. 5

  • 0-4-0 150hp, Diesel Mechanical Shunter
  • Manufactured by Robert Stephenson & Hawthorn Ltd. Works No. 6968
  • Delivered new to MoS, ROF Rotheras, Herefordshire, 1938
  • Moved to ROF DotH, April 1950 (Assumed to be a short loan)
  • Moved to ROF Rotheras, Herefordshire
  • Moved to J. W. Hardwick & Sons Ltd. West Ewell for scrap, circa 1962


Post War

There was a regular annual landscaping maintenance of the grounds, and some pest control in the spring, which was done by a Leicester company. The site saw little activity immediately post-war, but that was soon to change in 1956 with the Suez and Hungarian crises.

Suez Crisis

The last recalled "military" use was during the Suez and Hungarian Uprising crises in 1956, when the depot was used for the storage of shells, including American shells. The shells included Phosphor bombs.

The local construction company (based at nearby Hooton) of McAlpine, was employed to rebuild and repair the earthworks around the magazine sheds, and to repair the fences around the magazine earthworks – presumably to keep the cattle off. Additionally the lightning protection was re-done, consisting of three bands of one and a half inch copper strip over the roof and sides, connected to another band around the shed, which was in turn earthed to the railway track.

Post 1957, the site was used for storing Ammonium Nitrate in 2 cwt drums (112 pounds). This was stored in the open, and was later burnt off in the open air between 1957 and 1958. The local populace was informed by telephone before the burning off.


The signal box at Dunham-on-the-Hill Station (not the No.2 ARP signal box) station was closed around 1956, and demolished soon afterwards. There is a closure notice for the No.2 signal box for the 24th November 1951, this signal box was not demolished, and still stands to this day. Dunham-on-the-Hill station closed in 1952.

A BR Temporary Speed Restriction Notice, implemented during the closure of Dunham No.2 ARP Signal Box

Track lifting within the site started in early 1963, and finished in 1964. The labourers were bussed in from Walton Jail, in Liverpool. The track leading to the site was left in for the CEGB, who at the time had outline plans for a power station on the site, however, these plans did not come to fruition, and the track was lifted sometime in 1966/67.

The site was leased by Cheshire County Council, for several purposes, one is the obvious Travellers' camp, accessed from the A5117, the other being to use the earth embankments (which were actually clay), as an easily accessible source of clay to line the nearby Gowy land fill site. This explains why some of the "magazines" have had the embankment removed, and also explains the diagonal line present on some of the brick blast walls where the rail entrance would have been.

© Copyright Phil Pritchard 2008

The Rhydymwyn Valley History Society is funded by:

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