The most important part of any dry dock are the gates; once they are closed the water is pumped out so work can begin on the boat's hull. Therefore the gates must be strong and secure enough to prevent the water from entering and causing a catastrophic event while repair is underway.

Of all the remnants of the Rileys Hill Dry Dock, it is distressing to see the state of the gates, but they really cannot be replaced and therefore we should appreciate them in situ while they last.

The information board states that each gate weighed 9.5 tonnes but were so perfectly balanced that one man could open or close them. They were made of local Ironbark and sheathed in copper to prevent ship worm rot (I guess they eventually had a good feed). All the steel brackets and counterweights were forged in Sydney.


A classic shot of the one man operation to close the gates. It's interesting to note that the locks follow the principle of Leonardo Da Vinci's late 15th century invention of the mitred gate, when closed the pair meet at an angle and even a small difference in water level is enough to squeeze the gates closed and prevent any leaks. What an incredible invention from the man who painted the Mona Lisa!