A Monumental Folly
Throughout its operational life, Port Arthur struggled to reach an economically sustainable level of operation. In an ideal world the product of convict labour would provide the raw and manufactured materials necessary for the ongoing maintenance of the station and its occupants. In some regards Port Arthur managed this, with its flourishing timber industry fuelling building works throughout the Peninsula.
The meat, flour and vegetables necessary for rations would also be sourced from the farms of Port Arthur and the other Peninsula stations. All outstations and probation stations had tracts of land under the plough and hoe, Saltwater River and Safety Cove Farm being some of the biggest agricultural stations opened on the Peninsula. A sheep station and slaughtering establishment in the 1840s greatly furthered output.
Yet, despite these clear aims, the main weight of rations during the 1830s and especially the 1840s, had to be shipped down from Hobart. The 1841 introduction of Probation saw the authorities face almost insurmountable problems rationing the convict population, as the population rose from close to 1500, to over 3500 by 1844. A convict population of this size required over 2.5 ton of flour a day to fulfil the bread ration alone.
The Port Arthur water-powered flour mill and granary had first been suggested in 1839, with the authorities facing the imminent introduction of probation. The suggestions of the colonial Commissariat, who governed the convict ration supply, and Port Arthur's Commandant, saw the project started in 1842 - just as the Peninsula population began to rapidly increase.
An engineer, Alexander Clark, was brought in to oversee the mill and granary construction, as well as engineer the supply of water to the wheel. It was hoped that a mill and granary sited on the peninsula would supply the wants of the Convict Department, as well as produce surplus for export.
The whole undertaking was completed by 1845. Comprising a series of dams, millrace, underground aqueduct and overhead water race, getting the water to the 30ft (10m) water wheel was a much more complicated undertaking than anybody had envisaged. The mill and granary building itself was completed in just a year, housing not only a storehouse, wheel and machinery, but also a treadmill capable of taking up to 56 convicts at once.
However, the mill was to be a grand failure.
The infrastructure bringing the water to the wheel proved to be too complicated, losing water to seepage and evaporation. The supply of water itself was completely inadequate to feed the wheel. In the end, the mill only operated in intermittent bursts, quickly using up any store of water accumulated in the dam. Only a decade after it was first built, the mill was gutted and, between 1854 and 1857, converted into the Penitentiary, which in turn became Port Arthur's most enduring landmark.