An area of approximately 1,300 square metres of lower Thompson Square was investigated to depths of between 1-5 metres below ground levels during the Historical Salvage Excavation Programme. Open area excavation confirmed a high level of past disturbance to the archaeological stratigraphy of the site.
Large-scale landform modifications have been a repeated feature of the site, commencing as early as 1814-1816 with works carried out at the request of Governor Macquarie during the re-structuring of the ‘Green Hills’ settlement into the township of Windsor. Key to these works was the construction of an extensive brick drainage system providing sub-surface drainage for the settlement centred on Thompson Square; an early example of the numerous drainage works commissioned and constructed during Macquarie’s administration and a major undertaking for early Windsor. As a result of the salvage excavations, extensive sections of this drainage system were confirmed to remain in situ beneath lower Thompson Square (archaeological Phase 2). The system comprised of a central oviform drain on a north-south alignment running down to the river, fed by three bilateral ribs of box drain constructed at a higher level and connected to the oviform drain by rising sumps. In total, 48 metres of the oviform drain and 130 metres of adjoining box drains 1-3 were identified within the excavation zone.
This drain system is believed to have provided surface water drainage from George Street that reduced the effects of slope erosion, as well as waste water drainage from at least six separate locations; three in the government precinct to the east and three in the developing private frontages to the west. The full extent of the original and extant drainage system, including the uphill termination of the oviform sewer, has yet to be ascertained, however, a damaged section of the eastern arc of an additional, fourth box drain was identified beneath Old Bridge Street during test excavations in 2016. The 1814-1816 construction of the drains and the associated fills, as well as artefacts recovered during salvage, form the basis of much of the significant historical archaeological evidence that is the subject of this report. In addition, an area of undisturbed soil profile that formed the pre-1814 ground surface was identified and recorded (archaeological Phase 2). The salvage excavations demonstrated that the surviving extent of this historical soil profile was very limited (approximately 18 square metres), largely as a result of damage from the Phase 3 drain construction and associated earthworks.
From the combined Phase 2 and Phase 3 archaeological deposits, a total of 1,784 early historical artefacts were salvaged, representing an estimated 650 individual items in use prior to 1814. Ceramics formed the largest material class of the late 18th to early 19th century artefact assemblage, including high proportions of fragmented lead-glazed earthenware produced locally in the colony, and Chinese export porcelain wares imported from Britain were comparatively rare. Materials that are ubiquitous on the majority of other historical archaeological sites of the 19th century, such as whiteware ceramics and bottle glass, were infrequent, a reflection of this site’s early date.
The Phase 2 and Phase 3 assemblages provide a substantial collection of objects in use during the ‘Green Hills’ era of Windsor (1794-1814) that can inform future studies of the material culture in use locally and within the broader colony prior to 1820. The archaeological potential of this significant early period in Windsor is considerable. The Thompson Square assemblage provides a firmly dated range of material indicators for the identification of such sites that will, in turn, shed new light on the socio-historical context of the Thompson Square assemblage.
In addition to domestic refuse, a quantity of construction-related materials were recovered that reflect the scattered structures present during the Green Hills period and the removal of these buildings at the request of Macquarie in 1814. Information on the diet and personal lives of the early colonists was also recovered. Items retrieved included 1799 ‘proclamation’ coins, tobacco pipes, buttons, a pocket watch and firearms flints.
The construction of the Phase 3 drainage system marks the end of the direct occupation of the salvage area and commencement of its history as the public space of Thompson Square. The archaeological record reflects this, as no evidence of further activity relating to the mid-19th century history of Windsor (Phase 4) was identified during salvage. Evidence of extensive modifications to lower Thompson Square during the later 19th and into the 20th centuries (Phases 5 and 6) was methodically documented in order to confirm this and to determine the sequence and contexts of these various disturbance events and their influences on the early historical archaeological resource. Archaeological evidence dating from these later phases reflects the major events in the subsequent historical record of Thompson Square – the construction of Windsor Bridge, development of associated roads, tunnelling of a sewer main beneath the square in 1937, the construction of the Hawkesbury Motor Boat Club across much of the salvage area in 1949 and removal of this building c.1990.
As a result of these successive impacts, the fill stratigraphy across much of the site was found to be extensive (1-4 metres in depth) and to contain introduced and reworked material, including a further 1,947 artefacts salvaged in the process of dating the stratigraphy. The various disturbance events and fills were found to have further contributed to the almost total removal of the early historical landform and to directly overlie the disturbed Phase 3 drainage system and truncated natural sands predating European occupation (Phase 1).
With the exception of the brief construction phase of the drainage system, no in situ and direct evidence of the occupation of lower Thompson Square was identified, such as the structural remains of stores, dwellings or associated features indicating sustained activity. Historical documentation suggests such structures once stood within the modern boundary of lower Thompson Square and the absence of archaeological evidence of these is a direct result of the substantial past disturbances that have taken place following the earliest and most significant use of the site through to 1814.
A significance assessment of the drainage system and associated materials shows that these relics are of State significance, representing the archaeological context and extant fabric of one of only a handful of examples of early oviform drains surviving from the period. This classification is, in part, the result of the contribution that the archaeological excavation provides to the historical record, which provides a written account of the contract for these works and their place within the early restructuring in the vicinity of Thompson Square but which contains no physical description or plans of construction. Archaeological evidence of later phases of the site history is assessed to be of local significance.
The above information is extracted (and edited) from the Windsor Bridge Replacement Project Salvage Excavation Report – Area 1 – Historical Archaeology, AAJV, September 2019, pp. iii-v.