The Pluto Pipeline

Background
A reliable supply of petrol for the advancing Allied forces following the D-Day landings was of the highest priority. Planners knew that the future invasion of Europe would be the largest amphibious landing in history and without adequate and reliable supplies of petrol any advance would at best slow down and at worst grind to a halt. A loss of momentum could jeopardise the whole operation as German forces would have time to regroup and counter-attack. Conventional tankers and ‘ship to shore’ pipelines were in danger of cluttering up the beaches, obstructing the movement of men, armaments and materials and, in all circumstances, were subject to the vagaries of the weather and sea conditions and they were easy targets for the Luftwaffe.

The Pluto Pipeline (PipeLine Under The Ocean) was devised by the British Government to establish a pipeline under the ocean from the Isle of Wight to Cherbourg to provide petrol for the army.

Design
There existed already a fuel pipeline system around the country from before the war, running between Liverpool, East Anglia, Bristol, and the Isle of Grain on the Medway in Kent; that was a start, but how to build on it.

Two types of pipeline were developed: the flexible HAIS pipe with a 3 inch (75 mm) diameter lead core, weighing around 55 long tons per nautical mile (30 t/km), was essentially a development by Siemens Brothers (in conjunction with the National Physical Laboratory) of their existing undersea telegraph cables, and known as HAIS from Hartley-Anglo-Iranian-Siemens.

The second type was a less flexible steel pipe of similar diameter, developed by engineers from the Iraq Petroleum Company and the Burmah Oil Company, known as HAMEL from the contraction of the two chief engineers, HA Hammick and BJ Ellis. It was discovered in testing that the HAMEL pipe was best used with final sections of HAIS pipe each end. Because of the rigidity of the HAMEL pipe, a special apparatus code-named The ConunDrum was developed.

A section of the pipe with the layers successively stripped back

In true military fashion a ‘unit’ was required so Force Pluto was set up under the command of Captain J.F.Hutchings CBE DSO. It started with 100 officers and 1000 men, mainly merchant navy personnel. The ships involved included 4 cable layers totalling 25,000 tons, 5 Ocean going tugs for towing CONUN Drums, 6 Motor Fishing Vessels, 9 motor Barges with 9 Launches and 1Yacht.

The first tests on a pipeline system took place at Chatham on the Thames, when a 2inch pipe was tested in Chatham Dockyard. Next came deep water testing on the Clyde in Scotland. With the success of this it was time for a long term test to see if the system of pipe work would stand up to constant use.

Pipe Laying
Pipe laying became “Super Priority” for labour requirements and in June 1943, 8inch pipe was to be laid to the Kent coast from Walton on Thames to Lydd, near Dungeness, a distance of some 70 miles. If you were to lay a course from Walton on Thames to Dungeness you would find that it passes right by Epsom, but where exactly was the pipeline? We still did not have a good map showing the route. On the basis that officialdom would want to be ‘on the ground’ keeping an eye on the project, a clue to the route taken is that the Chief Signals Officer S.E. Regional Office was located at Tunbridge Wells in Kent, and the Command Centre for the area was at Reigate in Surrey.

The initial pipes were laid to Cherbourg (code name Watson ) some two months after D-Day and to Calais (code name Dumbo Far) as the war progressed.

In January 1945, 300 long tons (305 tonnes) of fuel was pumped to France per day, which increased tenfold to 3,000 long tons (3,048 tonnes) per day in March, and eventually to 4,000 tons (almost 1,000,000 Imperial gallons) per day. In total, over 781 million litres (over 172 million imperial gallons) of gasoline had been pumped to the Allied forces in Europe by VE day, providing a critical supply of fuel until a more permanent arrangement was made, although the pipeline remained in operation for some time after.

While people tend to think of Pluto as one pipeline in fact a total of 17 lines were laid on the Dumbo route before the end of the war.

Video of the pipelaying production & laying (starts at 3:35)

sources: Combined Operations, Epsom and Ewell History Explorer, BBC, Wikipedia, Swansea Heritage