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On December 19, after more than 30 years of planning, research and community involvement, the first of the Ironbark Creek floodgates was opened, marking a significant step in reinstating tidal flows to the estuarine wetlands of Hexham Swamp.
Photo captions from left to right: CMA Chairman Dr WEJ Paradice announces the opening of the first gate; Brett Peterkin and former CMA Program Manager for the Hunter Sharon Vernon operate the pully to officially open the gate; Ray (Bud) Kelly (front) and Ray Kelly Snr from Burrgati perform Indigenous story and dance, marking this important occasion for the local Awabakal people and the Hunter community as a whole. Hexham Swamp is an internationally recognised wetland covering 3800 hectares just 10 kilometres from Newcastle CBD and is the traditional land of the Awabakal people. The swamp is part of a vital corridor between the forests and bushland of the Watagans and Lake Macquarie, the wetlands of the Hunter Estuary, and the coast at Stockton Bight. 
As well as its value at a regional level, Hexham Swamp is recognised as a wetland of national and international importance, and provides feeding and roosting sites for at least fifteen species of migratory birds, protected under agreements between Australia, and Japan and China. The floodgates were built on Ironbark Creek in the 1970s to provide low lying urban areas with relief from flooding from the Hunter River and to improve farming productivity in Hexham Swamp. Just a few years later dramatic changes in the vegetation of the area had become apparent, as saltmarsh and mangroves were replaced by pastures and reeds, and alligator weed, pampas grass, and water hyacinth became prolific. 
Over time the loss of estuarine habitat within the swamp has resulted in a huge decline in the numbers of migratory and local shorebirds visiting the area, while the number of feral pigs, foxes and other pests has increased. Local populations of fish, prawns and other marine organisms have suffered severely from the loss of nursery areas. The opening of the first floodgate at Ironbark Creek is an extremely important step in restoring the once thriving estuarine wetlands. Click here to view a pictorial timeline of the historical events that have led to the opening of the first floodgate on Ironbark Creek. Follow these links for more information on the Hexham Swamp Rehabilitation Project or contact the CMA on 4930 1030 or email: hcr@cma.nsw.gov.au.
Breathing life back into Hexham Swamp The Hexham Swamp Rehabilitation Project is a partnership between private landholders, industry groups, local community and state and federal government agencies and aims to restore 1,946 hectares of Hexham Swamp to a healthy, functioning wetland. 
Hexham Swamp is the Hunter's largest and most biologically diverse wetland and one of the largest in New South Wales. But after thirty years of limited tidal exchange from the operation of floodgates at the mouth of Ironbark Creek, the estuarine, aquatic and terrestrial ecosystems of the wetland have become severely degraded. Lack of tidal flushing, vital to the health of an estuarine wetland, has dramatically changed the swamp's environment. A freshwater system has largely replaced the extensive mangroves and saltmarsh communities which once thrived throughout the swamp, significantly reducing vital aquatic and terrestrial habitat for native species. The once extensive saltmarsh plains have been replaced by dense stands of common reeds, which provide limited food and habitat value for fish and bird communities. The mangroves that once lined the creeks have either died, or are in a poor condition. Mangroves provide habitat for fish and other marine life as well as being an important source of leaf litter, which is a key component of many estuarine food chains. 
Both commercial and recreational fishers have been keen to see the swamp rehabilitated and vital fish habitat reinstated. Local fisherman Dennis Hirst is looking forward to the staged opening of the floodgates, as he believes there will be a significant increase in fish, prawn and crab populations in the Hunter Estuary. According to Dennis Hirst, Hexham Swamp was once one of the most important breeding grounds in the Hunter Estuary and also attracted hundreds of species of shorebirds, with many migratory waders visiting the swamp during their annual migrations to Australia. back to topInvolving the Hunter community Community concerns about the deteriorating estuarine values in Hexham Swamp came to the fore in the late 1980s, when groups such as the Hunter Wetlands Trust (now Hunter Wetlands Centre Australia) advocated increasing tidal flushing of Ironbark Creek. The Hunter Catchment Management Trust (the forerunner to the CMA) took up the challenge and established the Ironbark Creek Total Catchment Management (TCM) Committee, with a charter to investigate and report on the catchment and particularly on Hexham Swamp. The TCM Committee completed its report in 1996 and its key recommendations supported the case for returning the tide to Hexham Swamp. 
Endorsement of the Hexham Project has come from Federal, State and local government representatives and agencies, environmental groups, commercial fishing interests, researchers, neighbours of Hexham Swamp, and residents of the lower Hunter. These groups are represented on the Hexham Project Committee and continue to make a valuable contribution to the implementation of the project. Without the input and commitment of these individuals and organisations the Hexham Project may have just remained a good idea—but together, we’re making it happen. back to topYears of research and planning Much of this work was documented in the Environmental Impact Statement (EIS), which was approved in 2006 after extensive community consultation. The Minister for Planning approved the EIS with 57 conditions, which included construction works, water monitoring and flora and fauna surveys. 
One of the main recommendations of the EIS was that all eight floodgates should not be opened at once, but in stages to allow the effects of each gate opening—on plants, animals and water flows—to be monitored and appropriate action undertaken. The remaining floodgates will be opened progressively over the next few years, dependant on the impacts identified through careful monitoring, and the gates will continue to be opened and closed as required during floods and tidal events. Another major recommendation of the EIS was that privately owned lands that would be directly impacted by the project through tidal inundation be either purchased by the CMA or easements over the land established. The Minister for Planning, Hon Frank Sartor MP, approved the Hexham Project on 30 November 2006 under Part 3A of the Environmental Planning & Assessment Act 1979. To access the Environmental Assessment and supporting documents, as well as the Minister’s determination and Conditions of Approval, go to the NSW Department of Planning website and search for Hexham Swamp (number 05_0193). back to topWorking with property owners A major recommendation of the Environmental Impact Statement was that privately owned lands that would be directly impacted by the project through tidal inundation be either purchased by the CMA or easements over the land established. 
In 2000 a Memorandum of Understanding was developed between major landholders and the CMA that set the foundation for negotiations with individual landholders to begin. Public meetings were held to share information about the project and landholders were approached individually to either sell their land voluntarily or work with the CMA to develop easements for the inundation areas. All landholders were encouraged to seek their own professional advice and the CMA was reluctant to deal with landholders who had not sought professional and legal advice. Newcastle solicitor Nic Dan acted on behalf of the major landholders. The project raised some complex legal issues through the negotiations with individual government, corporate and private landholders and the project was extremely fortunate to have Freehills legal firm provide more than nine years of pro bono legal advice to the Hexham Swamp Rehabilitation Project. Their expertise was of great benefit, particularly in their innovative approach towards creating easements for inundation and navigating the project through complex State and Federal planning laws. One of the outcomes of the negotiations was the construction of a number of low level earthen bunds to restrict saltwater intrusion onto other private properties. Other construction works include the removal of causeways and the maintenance of access trails. Funds to purchase land were acquired through the Australian and New South Wales Government. One of the landholders who owned land in Hexham Swamp actually visited Canberra with the CMA in the early stages of the project, to encourage the government to support the project and provide funds for the property purchases. Negotiations with landholders began in 2000 and were finalised in December 2008. Of the 101 parcels of land, 28 purchases were voluntarily, 76 parcels had easements negotiated and only 7 easements were compulsorily acquired. back to topMonitoring the impacts A thorough Environmental Assessment has been undertaken on issues such as the extent of tidal inundation, its effect on grazing land and neighbouring suburbs, and any expected changes in mosquito numbers. Information has been collected over several years on the swamp, its vegetation, fish, birds, water quality, weeds and feral animals. As part of the Environmental Assessment, tidal inundation modelling was carried out by consultants BMT WBM Consulting to determine where tidal water would travel to. Properties that would be affected by tidal inundation were either purchased by the CMA or easements created over the land. Bunds (earthen mounds) were also constructed around areas to control tidal inundation. It is also important to note that water entering Hexham Swamp through tidal inundation is different to water running off the catchment in times of heavy rain, which causes flooding. Localised flooding will continue to occur within the catchment. The Minister for Planning approved the Environmental Impact Statement in 2006 with 57 separate conditions of approval for the project. These conditions included a staged opening of the floodgates and an associated monitoring program. This means that monitoring will be conducted following the first floodgate opening, and subsequent floodgates will only be opened if the impacts are within expected parameters. 
One of the other things the CMA will be monitoring is any change in the population of mosquitoes in the area. As part of the Environmental Impact Statement for the Hexham Swamp Rehabilitation Project, the CMA conducted some research on mosquitoes in the Hunter Estuary. Surveys were completed by Dr Cameron Webb from the Department of Medical Entomology, ICPMR and University of Sydney, Westmead Hospital. Saltmarsh mosquitoes are found throughout the Hunter estuary and are active during the warmer months. Rehabilitation of the Hexham Swamp will result in a decrease in the freshwater mosquitoes currently active at the site. Mosquito populations are currently being monitored and strategies related to management of water flows within the wetlands, including opening and closing the floodgates at strategic times, will be employed to minimise mosquito populations. Urban development directly adjacent to the areas to be inundated by tidal water is minimal and these areas are currently managing mosquitoes from existing wetlands and water systems. It is important that everyone in the Hunter region takes precautions to protect themselves from mosquitoes, as they are a natural part of our outdoor lifestyle. The CMA has supported a project coordinated by Hunter New England Health to help raise awareness of mosquitoes and minimise the risk to public health. For some tips on precautions you can take, go to www.mosquitoes.nsw.gov.au. back to topManaging feral pests and weeds Two of the main animal pests in Hexham are foxes and wild pigs. Foxes are a major threat in wetland areas where they feed on frogs and birds. This can be especially damaging when rare or threatened species are present. 
A comprehensive pest control program for the Hunter Estuary is being coordinated by NSW National Parks and Wildlife Service and involves the Hexham Swamp and Kooragang Wetland Rehabilitation Projects, Port Waratah Coal Services, Energy Australia and Maitland Rural Lands Protection Board. Some of the land owned by the CMA in Hexham Swamp is affected by environmental weeds, some of which have been declared noxious in NSW, including water hyacinth (Eichhornia crassipes), pampas grass (Cortaderia selloana) and alligator weed (Alternanthera philoxeroides). As well as these significant noxious species, there are many other common weed species in the project area including fireweed (Senecio madagascariensis), purple top (Verbena sp.), fennel (Foeniculum vulgare) and various thistles. While these weeds reduce habitat values in wetland areas, they are less likely to become a threat to the wetland ecosystem. One weed that could pose a major threat once the tidal regime is returned to Hexham Swamp, is spiny rush (Juncus acutus). This rush thrives in saline conditions and has the potential to become widespread throughout the swamp once tidal flushing is returned. A strategy has been developed, through the Hexham project, with Newcastle City Council and the NSW National Parks and Wildlife Service to control both weeds and pest animals in the swamp. back to top |
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