Motive power depot

Facilities are provided for refuelling and the replenishing of water, lubricating oil and grease and, for steam engines, the disposal of ash.

The equivalent of such depots in German-speaking countries is the Bahnbetriebswerk or Bw, which has similar functions, with major repairs and overhauls being carried out at Ausbesserungswerke.

The number of those was reduced drastically following the changeover from steam to diesel and electric traction, and most modern Bw in Germany are specialised depots, often responsible for a single locomotive class.

They were built by the railway companies to accommodate the locomotives that provided their local train services.

Others, such as Kings Cross engine shed in London, predominantly provided locomotives for passenger workings.

Many large rail connected industrial sites also had engine sheds, primarily using shunting locomotives.

Those in roundhouses could be inside, such as those at York in the UK, or outside, such as that at the East Broad Top Railroad & Coal Company in Rockhill, Pennsylvania, USA.

Study of photographs from the steam era show it was not uncommon for piles of ash to be scattered around the depot site.

After completing their last duty and arriving on shed, locomotives would have a regular boiler washout to remove scale, improve efficiency and protect safety.

The large east London depot of Stratford had an engineman's dormitory and its occupants would "wake up with a layer of coal dust covering them and the bed".

The major problem was the disposal of oil, which initially was left lying around causing pollution and safety issues.

The new depots were equipped to deal with diesel fuel and the ability to access the underside, as well as upper body work, was improved.