In Building the Steam Navy: Dockyards, Technology and the Creation of the Victorian Battle Fleet 1830 – 1906 by David Evans

Page 174 to 175

In an Admiralty visit to Portland in 1856 the development of Portland as a complete naval base to counterpose the French menace had been discussed, and (James) Rendel was asked to prepare a scheme. His death prevented his completing a design, but (John) Coode took over the task, and on the Admiralty visit to Portland in August 1859 he wrote a long letter to the Admiralty describing his Yard, the first to be specifically designed for the Steam Navy. This would be a state of the art undertaking, with three building slips, an outer basin and two inner basins, three dry docks and two coaling jetties. The whole dockyard was protected by a breakwater of its own. The latest technology, hydraulic machinery, was now incorporated in the coaling equipment.

All that materialised out of these grandiose plans were the mechanised coaling system and the great coal store.

There is a plan (TNA ADM 1/5730) of the dockyard and it looks like the breakwater we see today was also part of it and the facilities would have been more or less where what is there now is. The plan doesn’t seem to keep the proper scale as the two inner basins also appear to be far too small or the slipways and dry-docks are very big.

Also, all three basins appear to be tidal, without locks.

Does anyone have any additional information on this (basin, slipway and dry-dock size) and why it was never carried through?