Volume Six - Pre-Victorian to the Present Day - Select Aspects - The Pumping Engine House . . .

Why Pump Water into the Penarth Dock?

During a visit back to Penarth Dock Marina during March 2024, I met up with Mr. Stuart Jones, the Penarth Marina Manager, and was kindly shown a report prepared by Mr. Anthony Davies dating from early 1984 detailing the construction of the dock and basin.

Appendix D of this report clarified my lack of understanding of how and why the dock and basin (referred too as the 'Half-tide Basin') were intended to work from the outset and how each element of the locking systems interacted with incoming and outgoing traffic, time and tide. Remember that from 1865 until 1890 the centrifugal pumps previously described were not in place and hence, management of movement of vessels and water levels must have been an exceptionally skilled occupation! I add the text verbatim. [1292]

Appendix D - Half-tide Basins:

The half-tide basin was a feature incorporated into many of the docks of the 19th century. Their use was brought about by the increasing number of merchant vessels and the consequent inability of conventional lock systems to handle them. The concept of the half-tide basin was attributed to a certain Jesse Hartley. (1780-1860)

In its simplest from the half-tide basin consists of a basin connected to a main dock via one pair of gates and to the sea via one further pair of gates. The half-tide basin was used as follows:-

Vessels wishing to leave the dock would move into the half-tide basin just before the water level outside the basin was sufficient to allow them to navigate the entrance channel. Then the gates between the main dock and the basin would be closed and the basin sluiced down to the level of water outside. Then the entrance gates would be opened and vessels would leave and enter the basin.

This would continue until the level of water became too low to allow for the passage of vessels. When this occurred the entrance gates would be closed and the main dock sluiced down to the level of water in the basin, the gates between the basin and the dock opened and vessels allowed into the main dock to load or discharge cargo.