Impacts

This page, Impacts, presents the range of degrading impacts that have driven the ecological deterioration of the indigenous vegetation communities and streams of the catchment over the past 140 years or so. The environmental repair and management projects being undertaken by environmental managers and various bushcare groups to counter these impacts are outlined.

Historical degrading impacts on the streams and natural vegetation

Australian First Nations communities have lived in the Blue Mountains for many thousands of years. Lyre Bird Dell, Gordon Creek was one of many favoured dwelling places throughout this period (Knox, Stockton 2019). The Gully, at nearby Katoomba Falls Creek, Katoomba, was home to many individuals and families for decades until 1957, when dispossession was abruptly and brutally imposed (Johnson 2007). It remains a place of cultural significance for contemporary Blue Mountains Indigenous Australians.

As increasing numbers of settlers moved into south Katoomba and Leura from the 1880s, eucalypt forests were felled to to make way for housing (Armitage 1998). Fortunately, scenic escarpment and riparian areas were progressively set aside as public reserves, enabling a certain degree of indigenous plant and animal protection. Indeed, Leura Falls Creek and the Cascades, still bordered by dense stands of ferns and shrubbery, had become popular recreation venues by 1900.

'Meeting of Waters Katoomba' (Leura Falls Creek) approximately 1880s Source: Henry King National Library Australia
‘Meeting of Waters Katoomba’ (Leura Falls Creek) approximately 1880s Source: Henry King National Library Australia

However, the impacts arising from urbanisation continued to exert degrading influences on the reserves, adjoining areas of bushland, and the streams and tributaries. For example, a network of bare, hard surfaces had been created to service the new residential areas. Virtually all of the roads and footpaths of Leura were still in an unsealed condition by the 1940s, so for many decades expanses of earth and gravel were fully exposed to the abundant average annual rainfall of approximately 1300 millimetres per year.

The Deluge

As invariably transpires with a heavy Mountains storm, considerable damage was done to the roads and water-tables…loose earth disappeared before the onslaught of the rushing waters, exposing the metal in many places. The gutters as yet unflagged or concreted, were also heavy sufferers, the surface waters tearing great channels in their soft faces, and in places eating far into the neighbouring footway.

Blue Mountain Echo Friday 9 May 1919
'Harry Phillips first shop, Katoomba Street, Katoomba' Undated Source: Harry Phillips Blue Mountains City Library
‘Harry Phillips first shop, Katoomba Street, Katoomba’ Undated Source: Harry Phillips Blue Mountains City Library

Extensive quantities of mud, gravel and sand were inevitably swept into the stream network. The habitat of indigenous aquatic animals such as crayfish, platypus, macroinvertebrate bugs and small fish must have deteriorated rapidly.

The foundations for another serious environmental problem were also being laid, as residential areas within the catchment expanded in the late nineteenth century. Blackberry, a popular fruit, was thriving in the upper Blue Mountains by the 1900s, and not only in newly laid out gardens.

The Blackberry Pest


The blackberry is spreading over the fern gullies of the Blue Mountains, destroying the ferns and making desolate places which a short time ago were beauty spots. The growth of this pest is most insidious, and each year it claims for its own more of the beautiful natural growths of the Blue Mountains. This pest has already made its appearance on the Federal Pass at Katoomba, while other parts of the mountains are not free from it.

Goulburn Evening Penny Post Tuesday 3 November 1908

The Blackberry Pest On The Mountains
(From our Katoomba Correspondent.)


The serious question of the prevailing blackberry pest, and, its destroying effect on many of the Blue Mountains beauty spots, caused a lengthy discussion at the
last meeting of the Katoomba Council.

Lithgow Mercury Friday 31 March 1911

Contemporary management of degrading impacts

Weeds, erosive storm-water flows and pollution continue to exert degrading impacts on the urban reaches of the catchment’s streams, and their indigenous plant and animal life.

Storm-water erosion and subsequent weed spread Peter Carroll oval Source: John Hill 2005
Storm-water erosion and subsequent weed spread Peter Carroll oval Source: John Hill 2005

Further additions to the Leura Falls Creek catchment weed list have included Buddleia, Privet, Broom, Montbretia, Tutsan and Holly. These plants have degraded extensive areas of the catchment, overrunning fern glades, swamps and the indigenous stream edge vegetation.

Crocosmia x crocosmiiflora Montbretia (red flowers) overwhelming ferns Gordon Creek. Note excessive sand in stream bed Source: M Nugent 2020
Crocosmia x crocosmiiflora Montbretia (red flowers) overwhelming ferns Gordon Creek. Note excessive sand in stream bed Source: M Nugent 2020

Active environmental repair is now acknowledged as an essential component of local natural area management, if the catchment’s renowned natural environmental qualities are to be conserved. Blue Mountains City Council and NSW National Parks and Wildlife Service environmental managers and rangers, bushcare officers and bushcarers have worked to manage weeds directly on, or in proximity to the historical sites depicted on this page: the former sewage treatment plant in the Jamison Valley; Linda Creek and Prince Henry Cliff Walk; Leura Falls Creek, Meeting of the Waters, Leura Cascades, Bridal Veil Falls (historically referred to as Leura Falls) and Weeping Rock; Lyre Bird Dell and Gordon Creek; Amphitheatre Track and Cliff Drive.

Weed management, and also erosion control, pollution monitoring, rubbish removal and indigenous plant restoration have been important tasks. BMCC environmental managers have progressively installed storm-water control and treatment devices at key urban discharge points in the catchment, filtering and cleaning the urban water that flows into the streams (see Archives: Leura Falls Catchment Improvement Project 2014–2017). Members of the catchment’s bushcare groups have worked on these projects, assisting with planting, weeding and planning. Without this constant work, many of the sites and the streams pictured here would now be overwhelmed by thickets of weeds, and deep drifts of sediments and grit.

Members of Leura Cascades Bushcare Group have been working on these challenging issues for many years. Storm-water erosion damage at Leura Park has been remediated. Ecologically valuable areas of eucalypt forest and swamps in Leura Park and along Leura Falls Creek have been regularly monitored and successfully treated for weed infestation (see Archives). Group members have participated in the re-vegetation of a set of newly constructed storm-water management systems (see Archives: Leura Falls Catchment Improvement Project 2014–2017).

Bushcarers of the Govett Street Bushcare Group work to protect areas of remnant rainforest, eucalypt forest and swamps adjacent to a major Leura Falls Creek tributary. See https://govettstreet.bushcarebluemountains.org.au/about/.

Located upstream on the same tributary, the Vale Street Bushcare site includes a major gross pollutant trap and wetland system, which filters storm-water from Katoomba township. Members have targeted the establishment of an indigenous plant buffer zone around the wetland, and are restoring the riparian vegetation along the tributary (see Archives). See https://valestreet.bushcarebluemountains.org.au/

Significant environmental repair work has been undertaken on Gordon Creek for several decades. A recent initiative has targeted the rehabilitation of Rest Park swamp (Hartley Esplanade), the source of a significant Gordon Creek tributary. Gordon Falls Reserve Bushcare Group members have been managing serious weed and erosion issues along the creek for many years, on a regular monthly basis.

Also active along Gordon Creek is the National Parks and Wildlife Service sponsored Prince Henry Cliff Walk Bushcare Group (see Archives). Members of Everglades Landcare Group work to control the Agapanthus and a variety of other weeds that threaten a Gordon Falls Creek tributary.

BMCC environmental managers and Banksia Park Bushcare Group members have been rehabilitating the highly degraded upper tributaries of Banksia Streamlet since 2009. Storm-water flows have seriously eroded sections of the stream. Another problem was the dense infestations of Blackberry that were overwhelming the indigenous sedge Baumea rubiginosa, a key swamp plant species. Successful treatment of the Blackberry has been undertaken, stimulating a strong recovery by the sedge.

Before: treated Blackberry amongst Baumea rubiginosa sedge (centre right) 2009. Note Salix babylonica Weeping Willow (rear) Source: K NettleAfter: Thriving Baumea rubiginosa sedge 2014. Note Willow removed Source: K Nettle
Left/before: treated Blackberry amongst Baumea rubiginosa sedge (centre right) 2009. Note Salix fragilis Crack willow (rear) one of many infesting the swamp Source: A Nelson Right/after: Thriving Baumea rubiginosa sedge 2014. Willow removed; mowing adjusted Source: A Nelson

The Bushcare Officer and bushcarers of the NPWS Prince Henry Cliff Walk Bushcare Group also implement valuable environmental repair work on an additional Banksia Streamlet site in the National Park, tackling the weeds Tutsan, Privet and Japanese Honeysuckle. A storm-water management device has recently been installed; a biofilter pond removes sediments from storm-water before it enters the natural stream system.

This group also regularly targets Buddleia, Montbretia, Privet and Blackberry along stretches of the Walk and in the swamps and riparian zone of the Linda Creek catchment (see Archives). Additionally, members of this wide ranging group have undertaken valuable weed management work at Bridal Veil Falls, the Amphitheatre Track, the Federal Pass, extensive tracts of Leura Falls Creek below Leura Falls and at the former sewage treatment plant in the Jamison Valley.

Members of Sublime Point Bushcare Group have undertaken a major natural area restoration project on the plateau in recent decades. Over twenty five years, they have transformed a barren, disused quarry into a well vegetated riparian and woodland zone featuring pleasant walking tracks. See https://sublimepointbushcare25.com.au/

References

Armitage A M (1998) The Katoomba-Leura Story (Katoomba Rotary Club: Katoomba)

Johnson D (2007) Sacred Waters: The Story of the Blue Mountains Gully Traditional Owners (Halstead Press: Sydney)

Knox K Stockton E (2019) Aboriginal Heritage of the Blue Mountains: Recent Research and Reflections (Blue Mountain Education and Research Trust: Lawson)

Source: Catchment Group & BMCC

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