British railway milk trains

Milk trains were a common sight on the railways of Great Britain from the early 1930s to the late 1960s. Introduced to transport raw milk from creameries to food processing units in remote locations, they were the last railway-based system before the mass-introduction of pasteurization and the resultant industry use of road transport.

By 1923, the year in which almost all the railways in Great Britain were grouped into four national companies, 282 million gallons of milk were being transported annually by rail. Of this traffic the Great Western Railway, serving the rural and highly agricultural West of England and South Wales, had the largest share. It was followed by the LMS, which collected from Cumbria and North Wales; the Southern, deriving the bulk of its traffic from the Somerset and Dorset Railway; and finally the LNER, which served East Anglia.

The Milk Marketing Board (MMB) was created in 1933 and in 1942, during World War II, took control of all milk transport. By the late 1960s the MMB had switched entirely to road haulage, and only Express Dairies and Unigate continued to use rail transport.

A typical creamery would load a couple of milk tank wagons a day, with a single 3,000-imperial-gallon (14,000 l; 3,600 US gal) three-axle wagon carrying enough pasteurised milk to supply the daily needs of about 35,000 people. However, that same 12-long-ton (12,000 kg) wagon loaded with 3,000 imperial gallons (14,000 l; 3,600 US gal) of milk at 13 long tons (13 t; 15 short tons), weighed as much as a loaded passenger carriage: 25 long tons (25 t; 28 short tons). This resulted in the need to pull the heavy milk train with a high-powered express locomotive, in order to keep time delays to a minimum. Typical GWR locomotives deployed on milk trains included topline express lococmotives such as Kings, Castles and Halls, unlike the archetypal mixed-goods express or even slower but equally heavy coal train. After dieselisation in the 1960s, Western diesels were deployed on milk trains, again a typical passenger express locomotive on the time.

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