In 1826 the Land Commissioners highlighted the difficulties most travellers experienced in crossing the Derwent, with the main route to Launceston following the river to Roseneath where James Austin conveyed them by punt across the river to Herdsman's Cove. The Land Commission recommended the construction of a new crossing, offering a safe and speedy transit over the Derwent. Their preferred location was at the Black Snake (now Granton) where "an excellent quarry and the advantage of a sand bank extending half a mile in length to the Channel, which is here only three hundred and fifty yards across" were highlighted.
In response to the decision to construct a causeway across the River Derwent the Bridgewater Convict Station was established in 1828 on Ebenezer Geiss' grant at Black Snake. The station was west of the quarry on the southern side of the Causeway. Wooden barracks were constructed to accommodate the convict labour force (chain gang).
Work on the Causeway began in 1830 and a year later GTW Boyes visited the site and left an evocative if horrifying account of the cramped and draughty conditions. The convict cells at this time were about seven feet in length by 2ft 6inch in height. Extra buildings were apparently added after this. In 1834 ever concerned with the moral and religious sensibilities of their charges a chapel was erected at the station. There were 152 convicts there in 1832 and a maximum of 280 during the construction period, most in chains.
The quarry located opposite the Causeway provided the 1.80 million tons of crushed mudstone which was extracted by the convicts and wheeled to the end of the Causeway. Considerable problems were encountered establishing a firm base to the construction works because of the river silt and the clay base. The work was referred to as the "Bridgewater folly", where men tried for years to fill up a soft mud hole. The convict labour was supervised by John Lee Archer. The quarry face is a highly visible result of convict efforts to extract fill and stone to be used in the formation of the Causeway. The quarry site is significant as the sources of material for the Causeway, a major public works project which used convict chain gang labour, and was a major element in the transport link between Launceston and Hobart.
The quarry face is evocative of a past era of convict chain gang activity. It is symbolic of the pivotal role played by convict labour in the early development of Van Diemen's Land, dramatically illustrating the labour intensive nature and scale of work undertaken at the Causeway and is rare as part of a large scale public works project undertaken by convict labour forces during the period of transportation.
The site of the former Bridgewater Convict Station 1828-1849, is important as the location of the largest convict chain gang on the Main Road between Hobart and Launceston. This importance is enhanced by the scale of the works undertaken (principally the Causeway) and their importance in the development of the colony. The Causeway became the focus for colonial discontent with Governor Arthur from wealthy land owners who were concerned about the waste of public money. They believed that the convicts would have been more usefully assigned to work on their properties, instead of the Causeway, and would have preferred the funds spent on roads nearer their properties.
Convicts assigned to the causeway were men who had re-offended whilst serving their sentences. They were there for a definite time varying from one to twelve months, and on the expiration of their sentences they were either returned to their masters or transferred to Public Works for less painful employment. With only short intervals of refreshment and repose, they quarried stone, broke it, shaped it as required and wheeled it to the Causeway to form a foundation or to erect piers upon foundations already formed. A flogging triangle was in the courtyard. At one time four convicts attempted to escape from this station by jumping into the Derwent to swim to the other side. One of the convicts was hit by gunfire, and the other three were recaptured. The construction of the Causeway was a major public works project, being an attempt to solve the problem of crossing the River Derwent and more specifically the commitment of Governor Arthur to a major road between Hobart and Launceston. At the time of completion in 1836, and for some time afterward, the Bridgewater Causeway was regarded as the largest convict built civil engineering project yet undertaken in Australia. Neither the massive retaining wall in Victoria Pass in the western descent from the Blue Mountains in New South Wales or the road works of the Great North Road where it rises from the north bank of the Hawkesbury River are comparable in scale.
Even after the completion of the Causeway there was a substantial station with 17 military posted there in 1838. The station operated as a probation station from 1841(representing later development in the use of convict labour for public works), and from 1845 as a road station for parties repairing the Main Road. By 1847 the station was very rundown. LaTrobe visited the area and described its poor condition with some buildings being almost in ruins. At this stage there was one superintendent, two overseers and one storekeeper along with 66 convicts.
The station was decommissioned between 1847 and 1849. In 1847 the convicts were reputedly removed to Jericho in the Midlands. The station was still reported as open in 1849, possibly supplying some labour for the construction of a rolling bridge across the Derwent channel although by 1850 the station was no longer recorded as open. An 1886 plan shows that the site consisted largely of "traces of buildings".
The Commandant's Cottage and Stone End are significant elements remaining from the former Convict Station and the role it played in the construction of the Causeway. The Commandant's Cottage is believed to have been the main Officer's Quarters. It stands on a rise overlooking the Derwent River near the Causeway. The Commandant's Cottage is reputed to be the oldest building in the area, built in 1830 to house the officer or officers, in charge of the construction of the Causeway. The stonework on the house is of high quality, with each stone chosen with extreme care for artistic and color effect.
The Commandant's Cottage is important as one of the earliest buildings constructed in the Granton area. The Commandant's Cottage is a two storey Georgian building. It is of a near symmetrical layout. The windows are 12 pane sliding sash double hung windows and there are three dormer windows on the front elevation. It has a hipped corrugated iron roof. The top floor was added in 1974. The cottage was restored a number of years ago and is now a private residence.
Stone End is believed to be a late convict station structure reputedly the Chapel and hospital. Stone End is a single storey building of stone construction which has been altered over the years and is also privately owned.
The stone Watch House is situated directly opposite the highway/Causeway junction at Granton on the southern side of the River Derwent. It is reported to have been erected in 1838. It was there by 1847 when it is marked on an undated plan of the crossing made before the rolling bridge was constructed. It was constructed to house the soldiers who supervised the building of the Causeway. Plans to extend the watch house were completed in 1851 providing a Watch House Keeper's Quarters and Women's Lockup. When extended it included a male and female lock-up, watch house keeper's quarters, two exercise yards and a constable's office. The convicts were housed in a stockade at the rear.
It is believed that it may in fact have formed part of the earlier convict station complex and, on completion of the Causeway, assumed a watch house function. Its location illustrates the importance of the junction at Granton. The Watch House demonstrates the importance of having lock-up facilities in a district with a large convict population, and is significant as an early police building. The Watch House is a rare surviving example of a mid -19th century Watch House from colonial Tasmania.
The convict station site, the quarry and the Causeway are all parts of a historical process that resulted in the crossing of the River Derwent and the site has been assessed as having high archaeological potential to yield information on the layout and workings of a convict road station and chain gang providing insights into Governor Arthur's convict system.
Only two structures, "Stone End" and the "Commandants Cottage" from the convict road station appear to have survived to the present day. A small stone wall may also be a remnant of the period, it is reported that it was part of the cell block.
The quarry face is clearly visible for approximately 300 m in the Granton Reserve.
Text & Information sourced from Australian Heritage Database
A huge thank you to Netta & Mark Datlen, owners of the “Commandants Cottage” who graciously allowed me to take the photographs of their home.
