Why an island dockyard could be an advantage

Why place a major Sydney dockyard on an island without a bridge or rail connection?

Sea delivery suited its heavy equipment, while island access helped secure the dockyard and its supply flows.

The yard's large machinery arrived by sea from Britain and other industrial sources, making close ship access more useful than a rail connection. Machinery for turbine construction could be delivered by ship directly beside the industrial site. Island access also made movement onto and off the yard easier to monitor. In the historical transport context, maritime supply lines and dedicated docks made the location a practical industrial choice.