The Port of London Authority (PLA) took over the docks from the private companies. It was run by a board representing the private and public users of the port.
An important step taken by the Authority was the reduction and fixing of docking charges. This was a great help to merchants and ship-owners.
As well as running the docks, the PLA had overall control of the river from Teddington to the sea. It was responsible for managing the river, river traffic and pollution.
However, the PLA did not take over the wharves, which were left in private hands. The 'free water clause' remained, but lighters had to pay a registration fee to the PLA.
The PLA began to improve the docks and port facilities. The river was dredged to a depth that modern ships of deep draught could navigate.
The most important change was the construction of a new dock, south of the Royal Albert Dock, which could take very large ships. The new King George V Dock was completed in 1921. The Royal group of docks together formed the largest area of enclosed water in the world.
The new dock was well over a kilometre long (4000 feet). It averaged about 200 metres (650 feet) wide and had some 5 kilometres (3 miles) of quays. Its entrance lock from the river was about 250 metres (800 feet) long and 30 metres (100 feet) wide.
The maximum loaded draught of vessels using the dock was 10 metres (nearly 33 feet). This photograph of the George V Dock was taken from the air. It also shows the Royal Albert Dock.