Very little of the pre-European, natural landscape remains within Centennial Parklands. The Parklands as we know them today are the result of landscaping undertaken historically.
Although there has been extensive human intervention, the underlying geology, landform and drainage have also strongly influenced the formation of the Parklands. The following offers detailed information about the underlying geology and landform.
Geology and Pedology
The Parklands are located within the geological unit of Sydney known as the Botany Sands. The Botany Sands overlay the northern edge of the Botany Basin and are composed of a complex of Aeolian sand dunes of the Holocene era, of variable thickness, with an underlying layer of inter-bedded clays, peats and sands.
This material resulted in a natural landform of rounded sand dunes and expanses of gentle slopes with local depressions and exposed water tables (ponds and marshes). The underlying Quaternary Hawkesbury sandstone emerges to form a ridge to the north and east, and its more elevated and broken topography helps to define the spatial character of the Botany Sands system. It acts as a wall to the sand.
Natural drainage seeps through the blocky-jointed stone and collects in the natural aquifer (the Botany Sands), as well as in the intermittent surface streams and ponds which were formalised into the Parklands drainage system. The residential precinct of Lang Road, Martin Road, Cook Road, Robertson Road straddles a further north/south trending spur of Hawkesbury sandstone.
The original soil type for the Centennial Parklands is a white crystalline wind-blown sand of the Holocene era, overlying Hawkesbury Sandstone which outcrops at the northern edge of Centennial Park before dipping to depths of between eight to two hundred and fifty metres south towards Botany Bay.
Bands and lenses of Waverley Coffee Rock, a finely textured soft impermeable mudstone occur at numerous locations in the lower lying sections of the Parklands. The resultant podsolised soil profiles are azonal, acidic and with only weakly differentiated or non existent horizon development. Decaying vegetation provides humus in a thin upper A horizon with staining and discoloration of the prevalent white sand. Nutrient status is low, the absence of clay causing low cation exchange capacity, and particles in the fine to very fine range contributing to the drainage characteristics of the parklands.
Substantial modifications were made to the landscape in the late 1800s and in most areas a pattern of cut and fill has been used to create the current landforms. Original sands are typically identified by their whiteness, having been leached of nutrients.
The remnant sand dunes include Mount Steel (although highly modified on its northern aspect), the York Road area extending into Centennial Park, the Bird Sanctuary, Parade Ground Pine Grove, Randwick Gates Pine Grove, the Kensington Pond dune, and the Queens Park Road boundary. Some of these areas support elements of the remnant vegetation type known as Eastern Suburbs Banksia Scrub.
Although greatly altered by European occupation of the area, the topography was dominated by sand dune forms, exposed sandstone and erosion by water drainage. Slopes greater than 30 degrees are part of the north-west or south-east aspect of the Aeolian sand dunes around the periphery of the open space of the park. Other steep slopes are related to the construction of engineering works such as embankments to the ponds and water storage reservoirs.
A narrow plateau is formed by the natural sandstone ridgeline to the north of Centennial Park and to the northeast of Queens Park. The south-facing sandstone slopes provide a broken terraced effect. Isolated sandstone knolls also occur at lower points within Centennial Park.
Three major gullies are located in the central area of the Parklands. These were natural topographic features falling towards the former swamplands. The greatest range of elevation is from the 30-metre contour in the south-west corner to the 88-metre contour at the top of the Woollahra Reservoir in the north-east corner of Centennial Park.
Catchment hydrology and drainage
The Parklands ponds system is a modified remnant of the originally much more extensive freshwater wetlands at the head of the Botany Bay catchment. Land filling and urban development in the late 19th century has reduced the extent of these wetlands.
The area still functions as a catchment area with stormwater and surface runoff diverted from surrounding suburbs collecting in the Parklands and the vast and shallow groundwater table underlying the Parklands, before continuing downstream to the Botany Wetlands and Botany Bay.
The natural drainage from the local geology and culturally modified landscape is the area’s greatest asset. This feature contributed to its former function as grazing land and Sydney’s one-time source of water.
Twelve ponds, fed by sandstone and concrete lined channels, have replaced the original swamp. As well as channelling surface runoff there is natural seepage from the sandstone slopes and from the upslope water reservoirs.
The water resources of this area are likely to have been important to the Aboriginal people living here before 1788 but there is no known detailed information or clear descriptions of direct observations of people utilising the land and resources of the sand hills and wetlands on the eastern Sydney peninsula from early colonial writings.
Although the pre-colonial archaeological report prepared for the present Aboriginal history and heritage study did not investigate the nature of the country that existed before the sand hills in the area began to form, it indicated that Centennial Parklands may have been at the headwaters of small freshwater creeks which ran down sandstone valleys and into a river flowing across what is now the northern side of the then-dry Botany Bay, through present-day Botany Heads and over a short, then-dry section of the continental shelf to the ocean.
The character and configuration of the Centennial Parklands landscape has been influenced by:
natural evolution and ecological processes;
Aboriginal occupation and management;
establishment of the Sydney Common in 1811;
creation of part of the Common as the Lachlan Water Reserve in 1820 and the modification and management of wetlands and water courses;
transformation of the Common lands into three public parks during the latter half of the 19th century, each with its own distinctive and varied recreational uses; and
ongoing management and evolution of the maturing cultural landscape.
The overall landscape character unites the Centennial Parklands, in particular the consistent use of plants, especially the native figs and introduced evergreen oaks. The landscape is consistent with Victorian period planting styles, and is defined by expanses of grassed fields surrounded by umbrageous trees.
Late 19th century Gardenesque landscape plantings include occasional groves and clumps of trees which contrast and punctuate views, the minimal use of shrubs to maintain the flow of space and provide areas of useful shade, as well as the various ornamental ponds, gardens, monuments, statues and artworks which form focal points within the parklands. Strongly defined formal linear tree plantations reinforce the dominant road layout within Moore Park and Centennial Park, and contrast strongly with the naturalistic groupings in other locations.
Changes in planting have occurred and reflect fashion and the influence of a relatively small number of people, in particular the long association of the parks with the Royal Botanic Garden through directors Moore and Maiden, and overseers Jones, Forsyth and Sawkeld.
The spatial structure of Moore Park is a broad, flat and low lying area punctuated by modified remnant sand hills and water bodies with relatively straight lines of plantings following road alignments. Linear plantings have subdivided the park into a series of spaces, open in character yet defined by walls of trees.
Cleveland Street and Anzac Parade with their massive bordering figs may be read as grand 19th century boulevards bisecting the relatively empty open spaces. The South Dowling Street edge of Moore Park formerly bordered by a row of Moreton Bay Figs is visually dissipated in comparison.
In contrast, Centennial Park and Queens Park are partially contained by Hawkesbury Sandstone that has eroded into terraced slopes, gullies and cliffs providing greater spatial heterogeneity, and the opportunity for the development of a more artistically contrived landscape composition.
Centennial Park is distinguished from Moore and Queens Park by features such as a dwarf stone wall with iron palisade perimeter fence; a series of grandly conceived sandstone gates and associated lodges which mark the major access points; the encircling Grand Drive with its associated avenue plantation, and the picturesque quality of vistas and views across ponds and open fields punctuated by informal and ornamental plantings.
Gardenesque features such as the Busbys Pond horticultural precinct indicate the adoption of evolving design concepts from the more purely Picturesque taste represented in Moore Park.
The initial design has been modified by a succession of Directors, Head Gardeners, Overseers, Superintendents, Landscape Gardeners and Landscape Architects, as they responded to site conditions, Indigenous plants and changing styles. Thus the extant parklands landscape is the evolved outcome of that series of layers and interventions now present as a mature landscape composition.
For more information please refer to the Centennial Parklands Conservation Management Plan.