Wingecarribee Swamp | NSW Environment, Energy and Science

About us

Wingecarribee Swamp

Item details

Name of item: Wingecarribee Swamp
Type of item: Landscape
Group/Collection: Landscape - Natural
Category: Wetland or river
Location: Lat: -34.5760133564 Long: 150.5283626950
Primary address: Illawarra Highway, Robertson, NSW 2577
Parish: Kangaloon
County: Camden
Local govt. area: Wingecarribee
Local Aboriginal Land Council: Illawarra
Property description
Lot/Volume CodeLot/Volume NumberSection NumberPlan/Folio CodePlan/Folio Number
PART LOT2 DP562857
LOT2 DP879403
All addresses
Street AddressSuburb/townLGAParishCountyType
Illawarra HighwayBurrawangWingecarribee   
Illawarra HighwayRobertsonWingecarribeeKangaloonCamdenPrimary Address

Owner/s

Organisation NameOwner CategoryDate Ownership Updated
Water NSWState Government 

Statement of significance:

Wingecarribee Swamp is a remnant of a late glacial swamp. It is one of the oldest montane mires known in south-east Australia. Analyses of sediments dated from 15,000 BP (before the present) have provided valuable information about climatic and vegetation changes in Australia since the Pleistocene era.
Date significance updated: 24 Sep 98
Note: The State Heritage Inventory provides information about heritage items listed by local and State government agencies. The State Heritage Inventory is continually being updated by local and State agencies as new information becomes available. Read the OEH copyright and disclaimer.

Description

Physical description: A natural site, Wingecarribee Swamp is a remnant of a late glacial swamp overlying the Triassic sandstone and Wianamatta Shale of the Southern Highlands. The wetlands' peat deposits provide a rare resource for scientific study but are also sought after as a mining resource (RNE).

The swamp is in the Southern Highlands, backing on the Wingecarribee Reservoir (to its west) and forming the headwaters of the Wingecarribee River.

Wingecarribee Swamp forms the main headwaters of the Wingecarribee River which is a tributary of the Wollondilly River. It exists now as a remnant of what was probably a larger late glacial swamp overlying the Permian sandstone and wianamatta shale, and now mostly removed by the combined rejuvenation of the Wollondilly, Nepean and lower Shoalhaven catchments resulting from the last uplift of the sandstone plateau. Only Wingecarribee Swamp has survived intact, by reason of an unusual combination of geomorphic phenomena: it is surrounded on the north, east and south by low basalt hills which protect it from capture by tributaries of the Nepean and Shoalhaven Rivers, leaving a small outlet to the west into the gently west-dipping Wollondilly catchment. The swamp contains a rich assemblage of water and bog plants. Perched water table and impeded drainage has resulted in the the development of a deep acid peat swamp of late glacial age.

The swamp is the largest peatland in montane Mainland Australia with an area of about 7 square kilometres, an average depth of fibrous and humic peat of around 3m, and up to 10m of peat in some areas. Peatlands of this kind are rare in Australia and have developed in isolation from each other and related ecosystems. The accumulation of peat in the swamp is very rapid with most of the peat being formed in the past 25,000 years with up to 6m of very fresh peat preserved. This is a very rapid accumulation rate, especially for temperate Australia. Wingecarribee Swamp has a number of plant communites represented incuding EUCALYPTUS OVATA open woodland, POA AUSTRALIS closed tussock grassland, LEPTOSPERMUM OVATUM tall shrubland, SPHAGNUM CHRISTATUM mossland, CAREX GAUDICHAUDIANA closed sedgeland, PHRAGMITES COMMUNIS tall closed grassland, ELAEOCHARIS DULCIS-TYPHA MUELLERI open sedgeland, TRIGLOCHIN PROCERUM-CAREX sp aquatic sedgeland and LEPYRODIA ANARTHRIA open rushland which is the dominant community. The LEPYRODIA community found here is the richest and most extensive of this type known. There is an interesting extension of higher altitude taxa at this site and it might be inferred that the swamp has acted as a refuge for flora and possibly invertebrate fauna since the last cool period. One endangered plant species, Wingecarribee gentian, (Gentiana wingecarribiensis), is an endemic noted only from Wingecarribee Swamp. The nearest relative species is the alpine gentian. Botanical and palaeoenvironmental research has been carried out by several workers with studies continuing.

The peat deposits act as repositories for information about ecosystem history and environmental change in the locality. Fossil wood more than 35,000 years old has been recovered from the north-western margin of the swamp indicating the the swamp may be of this age. Studies of carbonised particles from cores taken from the swamp have inferred a regime of fire events over the 150,000 years prior to European settlement. It is possible that Indigneous values of National Estate significance may exist in this area. As yet these have not been identified, documented or assessed.

A reservoir floods the north west third of the swamp, which is not included in the listing. The dam does not detract from the ecological or palaeoecological values of the section of the swamp listed. Fibrous peat has been extracted from the swamp over twenty years from two mining leases with a total area of about 10ha so far effected removing the top 3m of peat. This only affects a small area of the swamp. The whole of the swamp is affected by human disturbance. Longitudinal drains about 40cm deep, run parallel to the water flow and remove some of the surface water allowing about sixty percent of the surface to be used as rough pasture. Evidence for burning of the swamp is seen as scorched shrubs and burnt fenceposts. Invasions by European weeds is at a remarkably low level except around the margins. Thus although the swamp has probably changed from its pre-European vegetational structure, it still preserves natural communities with the peatland still actively growing (RNE).

The adjacent Wingecarribee Swamp covers 340 hectares and is over 5000 years old. It is listed as an Endangered Ecological Community at both State and Federal levels and contains 4 threatened species: the plants Lyscimachia vulgaris var.davurica (yellow loosestrife); Gentiana wingecarribiensis (Wingecarribee gentian) and Prasophyllum uroglossum (leek orchid) and one insect, Petalura gigantea (giant dragonfly).(Knowles, 2008, 2-3).

Wingecarribee gentian is an endangered species under state and federal legislation. It is a highly localised plant restricted to small areas on the margin of Wingecarribee Swamp. It grows in low vegetation in spaghnum (moss) hummocks and patches of sedge. It is absent from most of the swamp apparently because dense reed cover and high water levels are unsuitable for its growth. Estimates made in 1992 put the population as low as 92 plants. In 1996 117 plants were located by NPWS staff, but in 1997 only 30. None were found in 1988. This is probably due to the swamp collapsing in August 1998, probably from drying of its habitat and the growth of other plants. The species was first reported at Wingecarribee swamp in the early 1960s, and first collected there for Sydney Herbarium collection by Hind in November 1967. The type (specimen: i.e. first collected/scientific published specimen) was collected in October 1973. Although named in 1988, the species was only re-discovered in 1992 by Kodela (Fairley, 2004, 90-91).
Physical condition and/or
Archaeological potential:
See physical description.

The SCA has devised a draft Heritage Strategy with Sue Feary (OEH). Engagement with the three relevant Aboriginal groups has not occurred. Archaeological evidence indicates that Aborigines used the margins of the swamp but it doesn't appear to be an area of high cultural significance compared to other swamps in the region.
The SCA's GIS layer now lists Aboriginal cultural sites on the swamp's margins as well as sites that are likely to contain Aboriginal artefacts. The SCA's environmental impact assessmnts (EIA) consider these sites and these potential high risk areas. SCA has not mapped non-Aboriginal heritage elements (yet)(SCA minutes, 6/8/2012 stakeholder workshop).
Date condition updated:24 Sep 98
Modifications and dates: The swamp has a history of disturbance with a portion being partly inundated with the construction of the Wingecarribee Reservoir in 1974. It was grazed for many years and had been burned frequently to provide green pick for cattle. It was also mined for peat. Peat mining ceased in 1998.

In August 1998 the swamp partially collapsed into the reservoir. The collapse cannot be attributed to any one factor but a high rainfall event coupled with instability, as a result of peat mining, and low reservoir levels at the time of the collapse, may have contributed. Spontaneous bog bursts have been documented from time to time in the Northern Hemisphere.

Following the swamp's collapse, its geomorphology changed dramatically, the peat fractured and a major channel was formed on its northern side. The vegetation was highly disturbed and bare peat was exposed. Turbidity (cloudiness) in the adjoining reservoir was over 300 NTU. A few months later willows (Salix sp.) growing on the margin of the swamp seeded and there was an explosion of willow seedlings germinating in the nutrient-rich bare peat.

The level of disturbance suffered by the swamp is too great to consider restoration as a feasible option for action, however management is focussed on the values the swamp still retains.

The swamp is now referred to by its post-collapse landform units: the intact, drying fissured channel and delta areas. The fissured areas have had a great deal of damage, while the delta - the mass of peat expelled into the reservoir - seems to be developing an ecological value in its own right. The delta area closest to the swamp is fairly stable, whereas the front rises and falls with the reservoir level but does not move laterally (Knowles, 2008, 2-3).
Further information: The Sydney Catchment Authority (SCA) and Department of Conservation & Climate Change (DECC) are joint sponsors of the Wingecarribee Swamp and Special Area Plan of Management (WSSAPoM) 2007. The SCA, as land manager for Wingecarribee Swamp, has the primary responsibility for delivery of the actions under the plan and DECC's primary role is provision of expert and technical advice. The WSSAPoM was approved in 2007 by the then Minister for the Environment, Bob Debus MLA, and built on works implemented under the previous plan of management - WSSAPoM 2001-6 (Knowles, 2008, 2).
Current use: Water catchment
Former use: Natural site; peat mining; grazing

History

Historical notes: A natural site, Wingecarribee Swamp is a remnant of a late glacial swamp overlying the Triassic sandstone and Wianamatta Shale of the Southern Highlands. The wetlands' peat deposits provide a rare resource for scientific study but are also sought after as a mining resource (RNE). It originally occupied an area of 600 hectares, and clear, fresh water of excellent quality emerged from its lower end. Its evolution took place over a period of about 10,000 years. Originally, a waterway ran down the shallow bedrock valley and became progressively choked with reeds and sedges. Anaerobic conditions and lower pH (acidity) developed in the plant litter which accumulated below the swamp vegetation as it expanded across the valley floor (White, 2000, 113).

The incomplete breakdown of the vegetable matter resulted in the formation of peat, and over time the depth of the peat deposit increased and living vegetation took root in it. Year by year this vegetation rose higher until it formed a continuous heath-like meadow of some 100 wetland species suspended 4-5m above the bottom on a column of peat of its own making. This organic sponge-like structure was strong enough to hold in dynamic equilibrium against the force of gravity 1 million tonnes (1000 ML) of water, which filtered through the peat to deliver clear, pure drinking water (ibid, 2000, 113).

It is home to at least five rare and/or endangered species - an orchid, a gentian (Gentiana wingecarribeensis), a yellow loosestrife, a giant dragonfly and a rare bird, the Australian bittern (ibid, 2000, 113). In the early 1900s, the NSW government resumed the swamp as a water supply for Bowral. In 1974 a dam and water treatment plant was built across its mouth, inundating the lower half and forming the Wingecarribee Reservoir. In 1993, the catchment, swamp and dam was acquired by Sydney Water, and a statutory plan was prepared in collaboration with the NSW National Parks and Wlidlife Service to manage and protect the ecosystem and the quality of water it delivered (ibid, 2000, 114).

The heritage value of the swamp was recognised by the Fauna Panel as long ago as 1967 and this was drawn to the attention of other government agencies, by the NSW National Parks and Wildlife Service, its successor during the 1970s. In 1990, the swamp was listed on the Register of the National Estate in 1992 ; as a landscape conservation area by the National Trust of Australia (NSW); and in 1993 as a wetland of national significance by Environment Australia. In 1996, the NSW Heritage Council recommended it be protected by an Interim Conservation Order, but this was not implemented until March 1998 (ibid, 2000, 113-4).

Peat mining began in 1967 under a pendency grant from the Mines Department, followed by a 20-year lease in 1972. When the lease expired in 1992, mining was allowed to continue. In the light of the number of protection orders and recognitions of the heritage value of the swamp, this was indeed surprising (ibid, 2000, 114) and irresponsible?). The peat was dredged from the swamp with an orange-peel grab mounted on a pontoon, floating on a 'dredge pool' of its own making. In late 1996, the Minister set up a Mining Warden's Inquiry, by which time the excavation had tripled in size since the leases expired. The inquiry continued through 1997, during which time mining was allowed to proceed. The mining company, Emerald Peat, argued for renewal of the leases and the Department of Mineral Resources supported its application, while Wingecarribee Shire Council, five state government agencies and many semi-government bodies and environmental organistaions opposed the application. In 1998, after collapse of the swamp, the Minister determined that the leases would not be renewed (ibid, 2000, 114).

The Sydney Catchment Authority (SCA) and Department of Conservation & Climate Change (DECC) are joint sponsors of Wingecarribee Swamp and Special Area Plan of Management (WSSAPoM) 2007. The SCA, as land manager, has the primary responsibility for delivery of the actions under the plan and DECC's primary role is provision of expert and technical advice. The WSSAPoM was approved in 2007 by the then Minister for the Environment, Bob Debus MLA, and built on works implemented under the previous plan of management - WSSAPoM 2001-6.

Wingecarribee Reservoir plays a pivotal role in the water supply system as water from Tallowa Dam is pumped up to this reservoir and then can be diverted to Warragamba Dam or Nepean Dam. The adjacent Wingecarribee Swamp covers 340 hectares and is over 5000 years old.

Wingecarribee Swamp is listed as an Endangered Ecological Community at both State and Federal levels and contains 4 threatened species: the plants Lyscimachia vulgaris var.davurica (yellow loosestrife); Gentiana wingecarribiensis (Wingecarribee gentian) and Prasophyllum uroglossum (leek orchid) and one insect, Petalura gigantea (giant dragonfly).

The swamp is a wetland of national and international significance (White, 2000, quoting Dr David Tranter). Highland peat swamps are internationally rare and significant among other factors for their role as habitat for migratory birds (Stuart REad, pers.comm. (from Plan of Management Monitoring Committee discussions/presentations, 11/5/2020).

The swamp has a history of disturbance with a portion being partly inundated with construction of the reservoir in 1974. It was grazed for many years and burned frequently to provide green pick for cattle. It was also mined for peat.

On the night of 8 August 1998 the swamp partially collapsed into the reservoir, after heavy rains. The pent-up head of water contained within the peat blew out, the water table dropped by several meters and the sides of the swamp fell in. The suspended mass of peatland vegetation was churned up, the dredge was washed into the Wingegarribee Reservoir immediately downstream, together with an archipeligo of peat some 5 million cubic meters in volume. A broad channel opened up right along the length of the swamp, allowing agricultural and urban run off to flow directly into the dam (ibid, 2000, 114).

The collapse cannot be attributed to any one factor but a high rainfall event coupled with instability, as a result of peat mining, and low reservoir levels at the time of the collapse, may have contributed. Spontaneous bog bursts have been documented from time to time in the Northern Hemisphere.

The cause of the collapse, as determined by two independent consultancy firms commissioned by Sydney Water, was the peat mining operations. Sydney Water declared the collapse of the swamp to be an 'accident', and set up an inter-departmental Steering Committee to advise on how to contain the damage (ibid, 2000, 114).

Following the swamp's collapse, its geomorphology changed dramatically, the peat fractured and a major channel was formed on its northern side. The vegetation was highly disturbed and bare peat was exposed. Turbidity (cloudiness) in the adjoining reservoir was over 300 NTU. A few months later willows (Salix sp.) growing on the margin of the swamp seeded and there was an explosion of willow seedlings germinating in the nutrient-rich bare peat.

The event made news headlines and captured the imagination and the media carried stories of 'exploding swamps', conjuring up a range of strange mental images. Seldom is there such a nice example of cause and effect, or such a visible demonstration of how human activities can destablise a natural system so that it reaches a critical threshold and ecological collapse is suddenly triggered by a not-unusual following event (ibid, 2000).

The swamp is draining, the peat is drying out (and will present a fire hazard - peat fires can burn underground for hundreds of years). We are witnessing the destruction of an entire ecosystem and irreparable damage to a valuable urban water supply. The two as-yet intact bays of peat at the swamp's southern side also appear to be drying out (ibid, 2000, 114).

The peat that had washed into the reservoir was kept clear of the water treatment plant by means of a strong rope, which is now being replaced with a permanent fence. Physical and chemical changes are being monitored. For 6 months, the water was too turbid to be handled by the treatment works (late 1998) so silt curtains were placed around the intake and the water so enclosed was dosed with alum to precipitate organic debris. The treatment works was upgraded at great expense and is now able to handle the water without alum dosing. The cost is being passed on to WIngecarribee Shire COuncil in water charges. Nutrient levels are very high and there is danger that cyanobacterial blooms will break out when the turbidity declines. Wingecarribee Reservoir, through the Glenquarry Cut, is used as a back-up for Sydney and Wollongong's water supply - so more than Bowral's water quality is at stake (ibid, 2000, 114).

The level of disturbance suffered by the swamp is too great to consider restoration as a feasible option for action, however management is focussed on the values the swamp still retains.

The swamp is now referred to by its post-collapse landform units: the intact, drying fissured channel and delta areas. The fissured areas have had a great deal of damage, while the delta - the mass of peat expelled into the reservoir - seems to be developing an ecological value in its own right. The delta area closest to the swamp is fairly stable, whereas the front rises and falls with the reservoir level but does not move laterally (Knowles, 2008, 2-3).

Historic themes

Australian theme (abbrev)New South Wales themeLocal theme
1. Environment-Tracing the evolution of a continent's special environments Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures. Cultural: Natural landscapes valued by humans-
1. Environment-Tracing the evolution of a continent's special environments Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures. Cultural: Lakes and wetlands supporting human activities-
1. Environment-Tracing the evolution of a continent's special environments Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures. Cultural: Rivers and water bodies important to humans-
1. Environment-Tracing the evolution of a continent's special environments Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures. Cultural: Conserving and protecting natural features-
3. Economy-Developing local, regional and national economies Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings (none)-
3. Economy-Developing local, regional and national economies Mining-Activities associated with the identification, extraction, processing and distribution of mineral ores, precious stones and other such inorganic substances. (none)-
3. Economy-Developing local, regional and national economies Mining-Activities associated with the identification, extraction, processing and distribution of mineral ores, precious stones and other such inorganic substances. Mining for peat-
7. Governing-Governing Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities. Developing roles for government - public water supply-

Assessment of significance

SHR Criteria e)
[Research potential]
Wingecarribee swamp provides a rare example of a peatland in south-east Australia. Peatlands are rare in this region and Wingecarribee because of its large size is classed as outstanding. The swamp is biogeographically significant. It has acted as a refugia for alpine flora and possibly invertebrate fauna since the last cool time approximately 10,000 years ago. An endangered species, GENTIANA WINGECARRIBEINSIS is known only from this
swamp its closest relative is the alpine gentian which now occurs only in the alps. This swamp is the best example of a montane peatland at comparatively low altitude in Australia. It is also the nothern-most significant peatland known in New South Wales. The dominant LEPYRODIA ANARTHRIA open rushland community is the richest and most extensive community of this type known in Australia. The swamp also provides an outstanding example of vegetation
dynamics as well as providing some of the best known stands of the swamp vegetation types represented. Wingecarribee Swamp has the oldest basal date of any montane mire known in Australia. Palaeobotanical and geomorphological analysis of sediments dated from 15,000 bp have provided valuable information about climatic and vegetation changes in Australia since the Pleistocene. Peatlands such as this swamp which accumulate over a long period of time have high research value. Their sediments act as repositories for valuable information about ecosystem history and environmental changes in the locality. Carbonised particles from cores taken from the swamp have provided important evidence of the impact of humans on the vegetation and landscape of the region since the beginning of the Holocene. (AHC - RNE)
Integrity/Intactness: Good
Assessment criteria: Items are assessed against the PDF State Heritage Register (SHR) Criteria to determine the level of significance. Refer to the Listings below for the level of statutory protection.

Recommended management:

Recommendations

Management CategoryDescriptionDate Updated
Recommended ManagementProduce a Conservation Management Plan (CMP) 
Recommended ManagementReview a Conservation Management Plan (CMP) 
Recommended ManagementRestrict access 
Recommended ManagementCarry out interpretation, promotion and/or education 

Procedures /Exemptions

Section of actDescriptionTitleCommentsAction date
57(2)Exemption to allow workStandard Exemptions SCHEDULE OF STANDARD EXEMPTIONS
HERITAGE ACT 1977
Notice of Order Under Section 57 (2) of the Heritage Act 1977

I, the Minister for Planning, pursuant to subsection 57(2) of the Heritage Act 1977, on the recommendation of the Heritage Council of New South Wales, do by this Order:

1. revoke the Schedule of Exemptions to subsection 57(1) of the Heritage Act made under subsection 57(2) and published in the Government Gazette on 22 February 2008; and

2. grant standard exemptions from subsection 57(1) of the Heritage Act 1977, described in the Schedule attached.

FRANK SARTOR
Minister for Planning
Sydney, 11 July 2008

To view the schedule click on the Standard Exemptions for Works Requiring Heritage Council Approval link below.
Sep 5 2008

PDF Standard exemptions for works requiring Heritage Council approval

Listings

Heritage ListingListing TitleListing NumberGazette DateGazette NumberGazette Page
Heritage Act - State Heritage Register 0078402 Apr 99 271546
Heritage Act - Permanent Conservation Order - former 0078419 Feb 99 22897
Heritage Act - Interim Conservation Order - Lapsed 94020 Mar 98 561767
National Trust of Australia register      
Register of the National Estate  15 Sep 90   

References, internet links & images

TypeAuthorYearTitleInternet Links
WrittenAustralian Heritage Commission Register of the National Estate
WrittenFairley, Alan2004Seldom Seen - Rare Plants of Greater Sydney
WrittenKnowles, Mary2008Brief History of the Swamp, in WSSAPoM Intergovernmental Working Group - Inaugural Meeting Minutes
WrittenSydney Catchment Authority2007Wingecarribee Swamp and Special Area - Plan of Management (summary)
WrittenWhite, Dr Mary E.2000Running Down - water in a changing land

Note: internet links may be to web pages, documents or images.

rez rez rez rez rez rez
rez rez rez rez rez rez
rez rez
(Click on thumbnail for full size image and image details)

Data source

The information for this entry comes from the following source:
Name: Heritage Office
Database number: 5001277
File number: S94/01385


Every effort has been made to ensure that information contained in the State Heritage Inventory is correct. If you find any errors or omissions please send your comments to the Database Manager.

All information and pictures on this page are the copyright of the Heritage Division or respective copyright owners.