Old Oak Common TMD

Old Oak Common TMD was a traction maintenance depot located west of London Paddington, in Old Oak Common. The depot codes were OC for the diesel depot and OO for the carriage shed. In steam days the shed code was 81A.

The depot was formerly the main facility for the storage and servicing of locomotives and multiple-units from Paddington. However The 'HST' section of Old Oak Common TMD, more commonly known as 'Old Oak Common HST Depot' closed in 2018 with the removal of the InterCity 125s from services on the Great Western Main Line (GWML). This closure was to make way for the development of the HS2 project. Maintenance of the new InterCity Express Trains is carried out at North Pole IET Depot which is situated opposite the site of Old Oak Common TMD whilst the Night Riviera sleeper train was transferred to Penzance Long Rock Depot in December 2017.

A new depot was built approximately a 1/4 mile to the east of the existing depot, primarily to service and stable the Class 345 trains that have been ordered for the Elizabeth line part of the Crossrail project. The depot opened in May 2018 and took the name of the existing depot.

The area is also where two Great Western Railway main lines divide: the 1838 route to Reading via Slough, and the 1906 "New North Main Line" (present-day Acton–Northolt line) via Greenford to Northolt Junction, the start of the Great Western and Great Central Joint Railway line. The former is in use for regular passenger services; the latter is used overwhelmingly by freight trains and empty coaching stock movements.