Information Sheet (sub-catchment)
S6 - Hunts Creek Sub-Catchment
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1.
General Description
The Hunts Creek corridor begins east of Jenkins Road, Carlingford
and continues to Lake Parramatta Reserve at James Ruse Drive
in North Parramatta. The corridor includes North Rocks Park,
Seville Reserve and a drainage reserve beside Northam Drive.
The majority of the creek contains remnant bushland, including
a large portion within the Kings School. The creek flows through
Hawkesbury Sandstone with most of the creek having eroded
a steepgully into the base rock. It forms a degraded but continuous
corridor of gully forest from Lake Parramatta to Carlingford.
2. Map Title
Hunts Creek Sub-Catchment Map
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Hunts Creek Sub-catchment includes Lake Parramatta
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3. Geology
Hunts Creek and its tributaries, which flow from the north-east
of the catchment, are incised into Hawkesbury Sandstone which makes
up the Hornsby Plateau. The ridge tops, such as at West Pennant
Hills, Castle Hill and Carlingford are capped by Ashfield Shales
belonging to the Wianamatta Group. In some isolated areas discontinuous
beds of the Mittagong Formation, interbedded sandstones and shales,
can be seen between the Ashfield shales and the Hawkesbury Sandstone.
The Hawkesbury sandstone was laid down as a very thick sheet of
sand by energetic, braided streams flowing from the south west during
the mid Triassic.
Sandstone cliffs and boulders are characteristic of the gullies
through which the creek flows. Exposure of the rock can be examined
in Lake Parramatta Reserve.
4. Geomorphology
Hunts Creek runs on a sandstone bed for most of its length. It
forms a continuous but degraded, corridor through the Hawkesbury
Sandstone from Carlingford to Lake Parramatta. Most of the creek
channel is steeply cut into the basement rock, the topography rendering
many of the creek sections difficult to access.
The hilly, rocky topography of both Hunts Creek and Darling Mills
Creek, contrasts with the undulating Cumberland Plain in the south
west of the Upper Parramatta River catchment.
5. Soil Types
In the sub catchment of Hunts Creek the soil is generally coarse
to medium grained sands and sandy loams. This tributary flows over
Hawkesbury Sandstones which are generally quartz-rich, coarse-grained
sandstones. The soil landscapes occurring in the Darling Mills Creek
and Hunts Creek sub-catchments include Hawkesbury, Gymea, Glenorie
and Lucas Heights. These soils are generally less than 100 cms in
depth, easily eroded even in low flow conditions and of low fertility.
The distribution of soils in the catchment reflects the underlying
geology. The two geological types being the Wianamatta shales of
the Cumberland Plain to the south and west and the Hawkesbury Sandstone
of the Hornsby Plateau in the north east. Darling Mills Creek and
Hunts Creek flow from the Hornsby Plateau and Hawkesbury Sandstone.
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6. Vegetation
communities
The majority of the creek valley contains remnant bushland,
most in the form of public reserves or within the grounds
of the Kings School. The geology, topography and soil supports
a variety of vegetation communities:
- Sydney Sandstone Gully Forest on the lower lying
areas along the entire creek length and particularly in
Lake Parramatta Reserve. The dominant species being Eucalyptus
pilularis (Blackbutt), Angophora costata (Smooth-barked
Apple), E. resinifera (Red Mahogany) and Syncarpia
glomulifera (Turpentine)
- Sandstone Ridgetop Woodland on the high ridgetops
in the Kings School, Lake Parramatta Reserve and Seville
Reserve with the dominant species being Eucalyptus piperita
(Sydney Peppermint), Angophora costata (Smooth-barked
Apple) and Blackbutt.
- Blue Gum High Forest in North Rocks Park with
canopy trees only such as Eucalyptus saligna (Sydney
Blue Gum), Angophra floribunda, (Rough Barked Apple),
Backhousia myrtifolia (Grey Myrtle) and Eucalyptus
resinifera (Red Mahogany). These trees are in mown grass
which has caused substantial loss of understorey.
- Sandstone/Shale Transition Forest occurs in Lake
Parramatta Reserve. This contains species from both woodland
and Sydney Sandstone Gully Forest.
- Epacris purpurascens var purpurascens is
a vulnerable heath species which grows in moist areas on
sandstone outcrop in Lake Parramatta Reserve.
A large potential seed bank exists in Lake Parramatta Reserve
that could be used to revegetate areas further upstream.
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 Shale
Sandstone Transition Forest in Lake Parramatta reserve |
7. Biodiversity
Lake Parramatta Reserve is primarily natural forest and the largest
bushland remnant surviving in the Parramatta LGA. The bushland is
representative of the shale/sandstone environment occurring between
the Cumberland Plain and the Hornsby Plateau and consequently has
a high level of biodiversity and is of regional significance.
In surveys undertaken in 1989 and 1990 there were 28 species of
native birds, 4 species of reptile and 2 native species of mammal,
plus several exotic species of birds and mammals.
The Hunts Creek sub-catchment supports a high diversity compared
to the rest of the Upper Parramatta River Catchment. For example
this Water Dragon at Lake Parramatta
Due
to the extensive nature and connections along the creek, Hunts Creek
has excellent potential for habitat. However in some sections the
influx of weeds threatens the survival of the native understorey.
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).
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. In contrast
creeks such as Blacktown Creek, Coopers Creek, Grantham Creek and
Greystanes Creek 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 creek is accessible from nearly all points where the reserve
has contact with the road, dense weed growth and topography notwithstanding.
The bush tracks provide excellent public amenity, particularly with
the small waterfall near Balaka Drive, North Rocks. However the
informal tracks, which riddle the reserve, are too numerous and
have compromised the quality of the bush. An example of this is
near Lindisfarme Park where lantana, privet, blackberry and native
Daphne flank the trail.
Of the isolated parks in the sub catchment only Woodstock Reserve,
Jenkins Street Reserve and North Rocks Park have remnant trees,
all other parks are grassed areas, sporting venues or planted with
exotic vegetation.
The Lake Parramatta Reserve is primarily natural bush with a walk
provided on the fire trail. It also has provision for picnickers
and people who enjoy the bush from a distance.
The entire sub catchment is zoned 6(a) excepting the Kings School
which is zoned 5(a), Special Use.
11. Social History and impacts on landuse and the environment
(incl. Aboriginal history)
 Rock
overhangs such as this one adjacent to Hunts Creek would have
provided much needed shelter near food and water for the Dharug
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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.
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As late as the 1940's the area which is now West Pennant Hills
was mainly a patchwork of agricultural fields. Residential development
was slower in this area due to difficult terrain, more dense bushland
and easier access along the Parramatta River and onto the Cumberland
Plain.
Today Parramatta and Blacktown are only two of the town centres
in the catchment which has become a thriving urban areas and 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.
The Darling Mills and Hunts Creek corridors have fared better than
most in the catchment as they contain the most substantial and intact
bushland in the Upper Parramatta River Catchment. This is in part
due to the steepness of the terrain which resulted in much later
development of residential and industrial areas. However recent
developments, upstream in Baulkham Hills and Carlingford are impacting
severely on the lower reaches of the creeks.
12. Community Groups
Several schools in the catchment carry out water quality testing
under the guidance of the Sydney Water, Upper Parramatta River Catchment
Trust Streamwatch program.
James Ruse Agricultural High School, Cumberland High School, Muirfield
High School, The King's School and Tara Anglican Schools for Girls
have been testing the water quality in the creek since 1993. The
Kings School is also revegetating significant remnant bushland on
their property.
13. Management Issues
Hunts Creek, although seemingly clean, is badly choked with weeds
in many places. From Jenkins Street, Carlingford, downstream and
west to Northam Drive, North Rocks, the creek is skirted with bush
tracks and the surrounding bush contains many informal tracks forged
by zealous bushwalkers. Although this provides public amenity, the
sheer number of trails increases the "edge effects", increasing
the influx of weeds and leads to erosion of the steep river banks.
The following strategies have been put forward to preserve this
very important bush corridor:
- Control stormwater run off and nutrient loads from adjacent
housing
- Educate residents and contractors working in local reserves
and parks to discourage illegal dumping of weeds, grass
clippings and other garden waste
- Remove exotic weeds from creek beds and replant with native
riparian and aquatic vegetation
- Investigate the installation of gross pollutant traps
at stormwater drains
- Plant riparian vegetation at stormwater outlets to reduce
the effects of chemicals washed from roads
- Discriminately block off some of the informal paths and
allow revegetation to occur
- Continue bush regeneration at Lake Parramatta
14. Lake Parramatta
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 Historical
Lake Parramatta Dam Wall flooding in 1997 |
In 1846 a committee of prominent citizens investigated Parramatta's
water supply. This resulted in the construction of a dam across
Hunts Creek in 1855. Lake Parramatta was the major water supply
for the district until 1909 when the Nepean became the water supply
facility as it had much greater storage and supply capacity. Lake
Parramatta remained a very popular swimming spot right through until
the 1960's, hundreds of locals used the reserve on hot days and
until the 1930's Australia's largest Freshwater Lifesaving Club
oversaw the safety of swimmers. However, in the 1970's due to increased
development in the catchment, water quality began to decline. Pollution
came from sewerage overflows and leaks, litter, nutrients, pesticides
and other chemicals from stormwater outlets and siltation from suburban
development in the headwaters of the catchment. By the late 1970's
the water in Lake Parramatta had declined to such an extent that
the Lake is now a polluted "no go" area.
Due to high nutrient levels from stormwater run off a thick mass
of weed, Salvinia, covered the entire surface of the Lake in 1994
to 1996. The weed, which was sprayed with herbicide finally sank
to the bottom and decomposed. The decomposition of the thick mass
of weed demanded large amount of oxygen from the water. Water testing
indicates the dissolved oxygen levels in the lake are still below
acceptable standards and high levels of faecal contamination and
nutrient levels indicate that sewerage overflows are contaminating
the waters of the lake.
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Lake Parramatta as it is today (left) and the harvester used
to remove the salvinia infestation (above)
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An attempt, in the 1990's, to improve the quality of the lake by
constructing a wetlands on the site where the "beach" used to be
did not work. The wetland species planted did not survive so the
project was abandoned.
Community consultation during the "Streamly Clean" project, run
by the Upper Parramatta River Catchment Trust, indicated that there
is a strong wish amongst local residents for Lake Parramatta to
be swimmable again by 2005.
15. Other
Resources and Links
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