The importance of water on steam-operated railways

Water management was - and still is - a very important part of operating a steam-powered railway.

Why is water important?

Steam locomotives burn coal, wood or oil to heat water and turn it into steam. The steam is then used to move pistons connected to huge rods that turn the locomotive's wheels. If a steam locomotive runs-out of water, either the firebox plug will melt (which is embarrassing for the fireman / driver and expensive to fix), or steam pressure will rise extremely quickly until either more water is supplied, or the boiler explodes. The latter is embarrassing (for the driver and fireman), expensive (for the railway company) and extremely dangerous (for anyone located within several hundred metres of the locomotive). When operating steam locomotives, it is therefore VITAL to have a plentiful supply of filtered (and reasonably clean) water available both when and where it is needed.

A supply of water is also needed for diesel and electric locomotives fitted with operational 'steam heat' boilers (where the steam generated is used to heat passenger carriages) and for a wide range of human uses including drinking, cooking, washing, cleaning, flushing toilets, etc. (both on-train and track-side). However, these uses are beyond the scope of this article.

How is a reliable supply of water provided?

Image 1: This reservoir in Garsdale was constructed by the Midland Railway Company to collect and store water for the troughs featured in image 3.

In order to meet this demand, railway companies construct water management systems. The key components of these systems include:

  • A reliable and reasonably constant source of fresh water. In many cases, a nearby river or lake will be adequate. However, where the availability of water is seasonal or otherwise ephemeral / unreliable, a reservoir will need to be created.
  • A sluice gate (for gravity-fed systems) or a pumping station (if the water source is lower than the tanks).
  • A filtration system (to remove debris).
  • A network of culverts and / or pipes (to move water between source, remote storage locations, lineside storage locations and the delivery system).
  • Water tanks and / or tank houses (to provide lineside storage).
  • Some form of water treatment system / process (usually chemical-based) to
    • prevent 'furring' of boilers (by reducing the amount of calcium carbonate in the water),
    • reduce foaming (which could be a significant problem when using water from peat-covered moorlands) and
    • reduce rusting of boilers.
  • A delivery system (to allow the tenders of steam locomotives to be filled 'on demand'). The delivery system usually takes the form of a set of water cranes or a set of water troughs.

How do the water delivery systems work?

Water Cranes

Image 2: This water crane at Appleby station is typical of the Midland Railway Company's swan-necked design. Note the floor-mounted valve (bottom-left), plus the brazier and chain below the swing-arm. The crane is supplied with water from the tank house beyond via an underground pipe.

Lineside water cranes usually include five key elements:

  1. A hollow vertical post connected via an underground pipe to a water supply (usually a lineside water tank and / or tank house).
  2. A large valve (to start, stop and control the flow of water).
  3. A counter-balanced hollow swing-arm fixed to the top of the post via a bearing plate. (The latter allows the arm to be rotated horizontally through at least 90 degrees).
  4. A flexible hose (to make it easier to guide the water into the tanks of a steam locomotive standing beside the water crane).
  5. A rope or chain attached to the swing-arm near the hose-end. This is used to both move and secure the swing-arm (the latter being important to prevent it fouling the loading gauge and hitting a passing train).

Traditionally the post and arm are made from cast iron and the hose from either leather or canvas.

To fill / refill a steam locomotive's water tanks, the train crew stops the locomotive next to a water crane and applies the hand brake. One member of the crew (usually the driver, but the roles are interchangeable) climbs on top of the locomotive's tender or side tank and opens the lid of the filling point. A second member of the crew (usually the fireman) uses the chain or rope to rotate the swing-arm over (or as close as possible to) the filling point. The driver then guides the flexible hose into the tank and holds it in position. The fireman opens the valve. The driver controls the hose and monitors the water level. On a signal from the driver, the fireman closes the valve. The driver then carefully lifts the hose from the tank as the fireman pulls the swing-arm away from the locomotive (leaving it secured and parallel with the railway track). During the entire process, both members of the train crew need to take care as they are at risk of being soaked with water.

Water Troughs

Image 3: The water troughs in Garsdale. Note the tank house in the distance (top-right). This was supplied with water from the reservoir featured in image 1.

On routes commonly used for long-distance passenger and freight services (like the Settle-Carlisle Railway) water troughs were placed between the rails of each running line and filled with water via a water tank (usually in the form of a tank house). These troughs allowed train crews to replenish the water supplies of their locomotives without having to stop the train.

As the locomotive reached the start of the water trough (usually indicated by a trackside marker board), the fireman would lower a scoop into the trough. The forward movement of the train would force water up the scoop, through a pipe and into the locomotive's tender or water tank. The fireman needed to take great care to both lower and lift the scoop at precisely the right moment:

  • Lowering the scoop too early or lifting it too late could damage both the locomotive and the water trough.
  • Lowering the scoop too late or lifting it too early could leave the locomotive short of water, thereby forcing the crew to add an unscheduled stop for water further along the line.
  • Taking-up too much water would cause the excess to escape explosively from the lid(s) on top of the tanks, potentially damaging the lids and possibly causing injury.

This method of taking-on water invariably created a lot of spray. If any windows were open in the train behind the locomotive, the passengers inside might get a bit damp, so train crews were required to warn passengers of this risk and to make sure that the windows in the leading carriages were closed when approaching a set of troughs. However, workers on the trackside near a set of water troughs faced the biggest risk: if they didn't time things right, they were likely to get utterly drenched (and then have to stay that way for the rest of their shift).

Water is self levelling, so water troughs can only be sited in locations where the railway track is 'level' (or in locations where the trackbed can be easily re-engineered to make it level). At Garsdale, the track formation is level for most of the length of the troughs. However, a short section of track at either end rises upwards at a gradient of 1 in 360. This seems to be a deliberate arrangement, perhaps introduced to reduce the amount of water lost via the bow wave in front of the scoop.

Does the weather have an impact?

In areas where temperatures might fall below freezing, the equipment associated with the water supply needs to be well insulated, heated, or both. For example:

  • Braziers (small coal-fired stoves) fitted with tall pipe-chimneys were often placed immediately beneath water craneswater tanks and tank houses to prevent the water inside freezing solid.
  • Water troughs were heated by steam pipes that ran the full length of each trough (the steam being generated by a boiler located in the nearby tank house).
  • A permanent way worker would be deployed to keep reservoir water outlets, etc. clear of ice and snow. The small hut visible in image 3 provided shelter, while the stove installed inside provide a source of heat to warm food and cold hands.

In areas where drought is likely, the reservoirs may need to be larger than normal and / or major engineering works might be required to move water over long distances (e.g. from a nearby hilly or mountainous area that has a higher / more reliable level of precipitation). This was not a problem within the SCRCA as the railway runs through the hills of North-west England and this area usually receives plenty of rain.

Note on terminology and gender

Throughout this article, the traditional terms 'driver' and 'fireman' have been used. However, in the modern world, neither of these roles is restricted to a specific gender.

Acknowledgements

Research and text by Mark R. Harvey (© Mark R. Harvey, 2012-2019).

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