Information Sheet (sub-catchment)

S5 - Greystanes / Girraween Creek

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1. General Description

3. Geology

Greystanes Creek, along with Grantham Creek, Finlaysons Creek, Pendle Hill Creek and Coopers Creek, drain from the south west of the catchment to join with Toongabbie Creek north of the railway line. These creeks flow across the Cumberland Plain which is a low, undulating plain underlain by horizontally bedded sediments of the Wianamatta Group, mainly Bringelly Shales. These shales are generally composed of claystones, siltstones and carbonaceous shales with sparse sandstone lenses. The sediments were laid down in a coastal alluvial plain during the middle Triassic, (200Ma).

The headwaters of Greystanes Creek are near Prospect Quarry. Prospect Hill is an intrusion of dolerite, which penetrated the Wianamatta Shales, (Ashfield Shale) during the Jurassic, (168 Ma). It has been quarried since 1901, the dolerite being used as "blue metal" on roads and railway lines. The quarry is soon to close as the useable material has been exhausted.

4. Geomorphology

The natural channel of the creek has been largely lost due to engineering and flood mitigation, however in the upper reaches, where the creek runs through CSIRO land it is in a semi-natural state. North of Fox Hills Golf Course the creek widens at the culvert and provides a wetland environment. The sub catchment of Greystanes Creek is generally low lying, undulating territory, the highest points being 140 metres above sea level at Prospect Hill and 122 metres at the Greystanes Trig station near Prospect.

5. Soil Types

The Greystanes Creek sub-catchment soils are generally fine-grained silts and clays. The predominant soil landscapes in the sub-catchment is Blacktown which has been formed by residual geomorphic processes. These soils are generally of low fertility and less than 100 cms in depth. In the lower reaches of the Creek, near the confluence with Toongabbie Creek, a much deeper, fluvial soil is evident along the creek margins. This soil is also of low fertility and is highly likely to erode in storm events.

6. Vegetation communities

The largest remnant of Cumberland Plain Woodland survives in the Boral Quarry at Greystanes forming a fragmented vegetation link along the creek in the CSIRO land to the public land of the corridor. This area is listed as a Schedule 1 Endangered Ecological Community (Threatened Species Conservation Act). Pockets of former River-flat Forest, (Casuarina glauca, Eucalyptus tereticornis, E. amplifolia and melaleuca linariifolia) survive in isolated patches.

7. Biodiversity

The remnant Cumberland Plain Woodland Forest near the quarry and in the CSIRO Research station is very significant as, in general, the small size and fragmented nature of many of the remnants limits the size and diversity of local fauna populations. Populations of feral animals such as dogs, cats, foxes, rabbits, Starlings and Indian Mynahs have replaced the native fauna in many of the isolated urbanised remnants.

Adjacent to the Bowling Club, along the lower reaches of the creek, dense indigenous and exotic vegetation provides important habitat for a range of native bird species.

8. Hydrology

Flow regime is the long term pattern of high flows and low flows in creeks and rivers.

Generally there is very little flow in catchment creeks for the majority of the time. 98% of total flow volume leaves the catchment 2% of the time, (Master Thesis, Downes, 1998). The exception to this is Greystanes Creek, which is sustained by water pumped out of Prospect Quarry at its headwaters. There is some concern as to what ecological impacts the closure off Prospect Quarry will have on the creek.

Dry weather, (base) flows are generally greater in Darling Mills Creek, Hunts Creek and their tributaries which rise in the Hawkesbury Sandstone areas in the north east of the catchment. The creeks that originate in the Wianamatta Shale country, that is, in the Cumberland Plain to the west and south, have very little dry weather flow.

9. Rainfall

Rainfall measurements between 1969 and 1996 show that there is a significant variation in the rainfall intensity and average in the catchment. The highest average rainfall occurs in the north-east section of the catchment, (headwaters of Darling Mills Creek, 1200mm per year) and the lowest in the south-west, (headwaters of Toongabbie and Greystanes Creek, 800mm per year).

10. Landuse

The upper reaches of Greystanes Creek corridor are on land zoned for special use at the CSIRO Animal Research Laboratory and the Fox Hills Golf Course. The northern sections of the corridor are in council reserves and zoned open space. The linear corridor area is mainly used for recreational walking and cycling and as a natural play environment by local children. Girraween Park provides playing fields for organised sports.

Prospect Quarry, which is on the western limit of the Upper Parramatta River Catchment has been a source of quarried "blue metal" since 1901.

11. Social History and impacts on landuse and the environment (incl. Aboriginal history)

The Upper Parramatta River catchment was originally home to the Dharug Aboriginal people who had inhabited the area for more than forty thousand years before British settlement in 1788. The local clan in the catchment was the Burramatta, from which the name Parramatta came, (burra meaning place and matta meaning eels). Many significant items of Aboriginal cultural heritage can be seen in the catchment, specifically in Lake Parramatta and Parramatta Parks, including such things as middens, tree scars, cave paintings and stone flakes.

The early settlement in Port Jackson faced many difficulties, not the least of which was the poor soil which would not support imported strains of wheat and other staple crops. Governor Phillip, who had explored the upper tidal reaches of the Parramatta River in 1788, encouraged establishment of new farms on the low lying river flats by giving land and convicts to the white settlers. This resulted in the development of the township of Rose Hill which later became known as Parramatta, the Aboriginal name meaning "the place where the eels lie down." Parramatta is Australia's second oldest settlement, having been established on November 2nd 1788. Lake Parramatta provided a clean and reliable water supply for the orchards and market gardens so the township flourished. With the introduction of rail transport in the 1850's Parramatta became the main metropolis of NSW.

Today Parramatta and Blacktown are thriving urban areas and make up a major regional centre. The catchment area of 107 km2, is 70% urbanised and contains approximately 80,000 properties and a population of 220,500 (Australian Bureau of Statistics, 1999). The cities of Parramatta and Blacktown are located at the perimeter of the catchment; Parramatta Central Business District being at the outlet, and Blacktown at the western extremity.

The long history of intensive use of the catchment has resulted in significant environmental management problems. Today factories, residences and commercial businesses cover the area, impervious surfaces such as roads, roofs and car parks result in more frequent flooding and all forms of land use, (residential, commercial, recreational and industrial), have caused severe deterioration in water quality.

12. Community Groups

The re-alignment and bank stabilisation of Greystanes Creek adjacent to the Bowling Club.

A full time site manager has been appointed by Holroyd City Council (with joint funding from Blacktown City Council and the UPRCT) to oversee further rehabilitation work in the Greystanes Creek corridor. This person will be most valuable in providing ongoing monitoring and coordinating volunteer activities and community participation. Community participation can be encouraged by establishing a campaign to foster community awareness and appreciation of the local creeks.

13. Management Measures in Place

14. Management issues

Revegetation along creek banks and corridor edges and rehabilitation of vegetation remnants has been carried out by local community and council groups. This has met with varying degrees of success. A continuation of rehabilitation work is needed and the following procedures have been suggested:

Protect and reserve, through appropriate council zoning, the woodland remnants at Boral Quarry and the CSIRO site to ensure that they are protected when the sites are redeveloped

· Install educational signs

· Increase policing to prevent dumping of litter and garden refuse

15. Other Resources and Links

• Greystanes Creek Sub-Catchment Map
• Upper Parramatta River Catchment Trust www.uprct.nsw.gov.au
• Nature Conservation Council www.nccnsw.org.au
• Department of Land & Water Conservation www.dlwc.nsw.gov.au
• National Parks & Wildlife Service www.npws.nsw.gov.au
• State Forest NSW www.forest.nsw.gov.au
• Holroyd City Council www.holroyd.nsw.gov.au