The Colne Valley Waterworks railway was an industrial

Industrial railway

An industrial railway is a type of railway that is not available for public transportation and is used exclusively to serve a particular industrial, logistics or military site...

 narrow gauge railway connecting the London and North Western Railway

London and North Western Railway

The London and North Western Railway was a British railway company between 1846 and 1922. It was created by the merger of three companies – the Grand Junction Railway, the London and Birmingham Railway and the Manchester and Birmingham Railway...

 (LNWR) Watford

Watford

Watford is a town and borough in Hertfordshire, England, situated northwest of central London and within the bounds of the M25 motorway. The borough is separated from Greater London to the south by the urbanised parish of Watford Rural in the Three Rivers District.Watford was created as an urban...

 to Rickmansworth

Rickmansworth

Rickmansworth is a town in the Three Rivers district of Hertfordshire, England, 4¼ miles west of Watford.The town has a population of around 15,000 people and lies on the Grand Union Canal and the River Colne, at the northern end of the Colne Valley regional park.Rickmansworth is a small town in...

 branch line with the Eastbury Pumping Station.

The Colne Valley Water Company opened the Eastbury Pumping Station near Watford in 1873. In 1931 the company opened a narrow gauge railway connecting the pumping station with the LNWR's standard gauge

Standard gauge

The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

 branch line between Watford and Rickmansworth. The line ran southeast from a private siding on the LNWR line, crossed the River Colne

River Colne, Hertfordshire

The Colne is a river in England which is a tributary of the River Thames. It flows mainly through Hertfordshire and forms the boundary between the South Bucks district of Buckinghamshire and the London Borough of Hillingdon...

 by a relatively substantial plate girder bridge and ended in a yard at the pumping station. The railway carried coal

Coal

Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

 to power the pumping station

Pumping station

Pumping stations are facilities including pumps and equipment for pumping fluids from one place to another. They are used for a variety of infrastructure systems, such as the supply of water to canals, the drainage of low-lying land, and the removal of sewage to processing sites.A pumping station...

 and chlorine

Chlorine

Chlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...

 and salt

Edible salt

Salt, also known as table salt, or rock salt, is a mineral that is composed primarily of sodium chloride , a chemical compound belonging to the larger class of ionic salts. It is essential for animal life in small quantities, but is harmful to animals and plants in excess...

 for the water softening plant.

The pumping station switched from coal to diesel power in 1956; after this use of the railway declined significantly. Chlorine and salt were still carried by rail. The line closed in 1967. The two locomotives were purchased for preservation.

Locomotives

Number	Builder	Type	Date	Works number	Notes
1	Ruston & Hornsby Ruston (engine builder) Ruston & Hornsby, later known as Ruston, was an industrial equipment manufacturer in Lincoln, England, the company's history going back to 1840. The company is best known as a manufacturer of narrow and standard gauge diesel locomotives and also of steam shovels. Other products included cars, steam...	4wDM	1932	166015	Preserved at the Amberley Chalk Pits Museum in 1968
2	Ruston & Hornsby Ruston (engine builder) Ruston & Hornsby, later known as Ruston, was an industrial equipment manufacturer in Lincoln, England, the company's history going back to 1840. The company is best known as a manufacturer of narrow and standard gauge diesel locomotives and also of steam shovels. Other products included cars, steam...	4wDM	1933	166024	Preserved at the Amberley Chalk Pits Museum in 1968