Dockyard Timeline

1912 - Largest Floating Dock Arrives Portsmouth

2^nd August. Worlds largest Floating Dock arrived at Portsmouth. It covered an area of 2¼ acres with lifting capacity of 40,000 tons. It was moored in Fountain Lake. (see 1939) This floating dock was built by Messrs. Cammell Laird, Birkenhead

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Length Overall…...........................................682 ft.

Breadth Overall….........................................159ft - 6in.

Breadth Inside…...........................................118 ft.

Breadth inside, Clear….................................107ft – 5in.

Draught, light….............................................6ft – 4.5 in.

Displacement, Light…...................................14,700 tons

Standard lifting power…................................32,000 tons

The dock was fitted with 8 sets of reciprocating pumping engines of the impeller type that could pump 48,750 tons of water in 4.5 hours. Power was supplied by 8 Babcock & Wilcox boilers. The dock was also equipped with electrical generators. This immense structure covered an area of two & a quarter acres, with a lifting capacity of 40,000 tons. A jetty, costing £100,000 was built at Fountain Lake Jetty so that repair material for the ships docked could be brought alongside. With this addition, by 1914, Portsmouth could dry-dock up to five Dreadnoughts at any on time. At the outbreak of World War 1 the dock with No.1. Crane Lighter inside it was towed to Invergordon, where they remained until the end of hostilities, rendering valuable service to the Grand Fleet. See: http://www.theinvergordonarchive.org/groups.asp?id=42. The dock was safely brought back to Portsmouth but the crane lighter was wrecked on the East Coast.