A network of underground fuel tanks for storing aviation fuel, linked together by a pipeline was built in the hills to the north of Milford Haven in the mid 1930’s. There were three groups of tanks, two of two tanks (two either side of the road), one of three tanks and one of five tanks.
The tanks were supplied by sea with tankers unloading directly into the pipeline, or by train. The railway siding in the docks is still extant.
After the war the tanks were connected to the national distribution network remaining in use until the 1970’s. This fuel network supplied all the major bomber airfields during the cold war.
The largest group of tanks is at Haven’s Head just above the docks where five buried tanks are linked by a tunnel carrying the underground pipeline.
The other groups are at SM900070 with SM893071 and SM894071.
At Haven’s Head a tunnel can still be accessed from a small pump house hidden behind two brick and concrete buildings a short distance to the west of Tesco’s in the centre of Milford Haven. There is a high locked grille preventing access to the building and tunnel. From this point the pipeline ran down to the exchange siding at Milford Haven Docks.
From the entrance, the tunnel with four parallel oil pipes is inclined steeply upwards for forty feet; there are steps alongside for pedestrian use. The pipes are of approximately 12” in diameter. A fourth pipe of slightly narrower diameter is mounted on a framework above the four pipes at this point. At the top of the incline the tunnel slopes gently upwards (north) through the Haven’s Head tank farm, with four tanks on the left and one on the right. In the tunnel there is a wall with a steel door between each tank for isolating the tanks in the event of leakage or fire.
At each tank there is a feed from two of the four parallel pipes passing through a series of valves into the tank. There is a circular inspection hatch in front of each tank which is securely bolted in place. Opposite each tank there is a short stairway up to a wooden door out to the surface. Each of these doors is blocked with soil and rubble at the surface.
The tunnel, including the incline, is approximately 250 yards in length, 7 feet high and rectangular in section. The fuel pipes and valve gear remain in good condition. A smell of aviation fuel pervades throughout the tunnel system.
There is no underground access at either of the two other remaining tank farms.
- Bob Jenner
- Roger JC Thomas