Inland Waters

INLAND WATERS Water Quality Trends • Condition of rivers and creeks with respect to their nutrient and turbidity levels: STABLE generally in a moderate to poor condition. • The change in river health as indicated by macroinvertebrates (with the exception of the River Murray): DECLINING due to the effects of the prolonged drought. • Groundwater quality: STABLE throughout most of the state although nutrients remain poor in many regions and salinity is increasing in some. Goal South Australia’s creeks and rivers support T3.9 Sustainable Water Supply: South important aquatic ecosystems that Australia’s water resources are managed sustain a diverse range of plants and within sustainable limits. animals. Some supply drinking water South Australia’s Strategic Plan 2007 for much of the state’s population, particularly those linked to Adelaide’s reservoirs in the Mount Lofty Ranges. They also sustain much of our irrigated Water Quality and a agriculture, manufacturing, food sustainable South Australia processing and winemaking industries and provide a focus for water-based zone they occur as mound springs and Inland waters include creeks and rivers, recreational activities and eco-tourism. seasonal swamps. wetlands, lakes and groundwater systems. The pollution of creeks and rivers and Also found along the coast as mudflats The chapter does not review the state of the reduced flow volumes compromise and salt marshes, wetlands are generally River Murray, which given its prominence is these values, which are also impacted areas of standing, rather than flowing dealt with separately. from natural disturbances such as floods, water. They can be permanently, Creeks and rivers are generally flowing prolonged drought and bushfires. seasonally or episodically wet and all water habitats, although they may dry out undergo varying degrees of drying seasonally. In the arid zone creeks may flow Wetlands during hot, dry summer months. only occasionally and can flood across vast Wetlands are the swamps, lakes and Among the most biologically productive areas, but typically the only aquatic habitats marshes found along rivers and on and diverse habitats on the planet, consist of disconnected pools. floodplains. In low-lying areas of the arid wetlands perform important functions 38 STATE OF THE ENVIRONMENT REPORT 2008 Water Quality KEY FACTS Partly wooded swamp, Cooper Creek system. Photo: Wetlands International. Goyder Lagoon. Photo: Wetlands International. that include the biochemical Impact of Deteriorating Water Quality transformation and storage of water, Drinking water quality and human health production of living plants and animals, and decomposition of organic matter. Many rivers and creeks in the Mount Many also have significant recreational Lofty Ranges and the River Murray Basin and tourism values, e.g. Coongie Lakes, are source waters that feed into major Lake Eyre and the mound springs in the metropolitan reservoirs and groundwater- Far North, and Blue Lake in Mt Gambier. based supplies. In the South East and numerous remote communities, Other wetland values include their groundwater bodies are also vulnerable spiritual and cultural significance for to pollution arising from overlying Indigenous Australians, importance land use. Densely wooded swamp, Cooper Creek system. in some areas for grazing stock, and Photo: Wetlands International. in others as sites for research and Deteriorating water quality potentially community involvement in monitoring impacts on drinking water quality, and sometimes managing specific affecting human health (the protozoan habitats. parasites Giardia and Cryptosporidium are frequently detected in the source ‘Groundwater is Wetland areas have however, been waters of major reservoirs), and increases extensively modified, filled and drained the public health risks associated with also fundamental to since European settlement and close water treatment process failure and to 90% of those in southeastern South additional treatment costs in some maintaining flows in Australia have been lost (Spiers 1999). instances. Substantial funding is being According to the Department of directed to the amelioration of these many of the state’s Environment and Heritage (DEH, 2003), risks by improved riparian zone and other approximately 30% of wetlands existing catchment management actions. creeks, rivers and before European settlement along the Fleurieu Peninsula remain, with just 1% There are potential risks to human of the original extent of wetlands in a health if groundwater contaminated wetlands.’ pristine condition. with disease-causing micro-organisms or a high concentration of nitrate from Groundwater fertilisers, stock and septic tanks is used for drinking purposes. Organic solvent South Australia’s groundwater resources contamination of groundwater can also are also critical to the state, providing be a problem for safe use of the resource. social, economic and environmental benefits. Groundwater provides a Reduced productivity significant amount of the state’s irrigation water for horticulture, agriculture and The use of irrigation water that has viticulture and is an invaluable drinking high salinity or boron levels can affect water supply to regions where there is horticultural and agricultural productivity little surface water run-off and effective by affecting plant and soil health. storage sites are unavailable. Damage to infrastructure Groundwater is also fundamental to maintaining flows in many of the state’s High salt content in water can corrode creeks, rivers and wetlands. water distribution systems and cause STATE OF THE ENVIRONMENT REPORT 2008 39 INLAND WATERS Brukunga Mine Brukunga mine, situated 4km north of Nairne in the Mount Lofty Ranges, operated between 1955 and 1972 to extract iron pyrites minerals that was used for the production of sulphuric acid and superphosphate. Acid drainage from the exposed quarry floor, overburden dumps and metallurgical concentrating plant tailings in an adjacent valley polluted the Dawesley Creek, making water unfit for livestock consumption and affecting biodiversity in the watershed. In 1977 the state government accepted responsibility for rehabilitation of Brukunga and three years later commissioned a lime neutralisation plant to treat acid water. Nestlings of Nankeen Night-heron. From 1988, with the collaboration of schools and conservation volunteers, the once- Photo: Wetlands International barren tailings dams have received a cover of soil and have been progressively revegetated. ‘Poor water quality In 2003, water in Dawesley Creek was diverted past the mine, restoring downstream use for livestock and irrigation. Water collected from the mine site is captured before can potentially cause entering the creek and neutralised with lime, resulting in a gypsum-like mud, which is being progressively spread over parts of the old quarry and revegetated to stabilise permanent and it and reduce acid runoff from the site. irreversible damage to ecosystems and destroy valuable habitats if left unmanaged.’ The rehabilitation of the tailings dam area at Brukunga. Photo: PIRSA damage to household appliances and survive, such as coastal springs and industrial infrastructure. underground fauna (stygofauna). Increased water treatment costs Recreation and tourism Deteriorating water quality can have Polluted water bodies jeopardise an economic impact associated with recreation and tourism activities and additional water quality management lead to closures, particularly after rainfall actions, including increased treatment events. Blue-green algal blooms, such costs to make the water safe and as those that can occur in Torrens Lake palatable for drinking. over summer months, may generate odours and be toxic, restricting Biodiversity recreation. Declining water quality will have an Elevated turbidity reduces recreational impact on the health of aquatic plant safety and the aesthetics of some waters. and animal communities, particularly pollution from heavy metals, high nutrient and salinity levels and extensive algal blooms. Indicators Poor water quality can potentially cause CONDITION INDICATORS: permanent and irreversible damage to ecosystems and destroy valuable • Exceedences of water quality guidelines habitats if left unmanaged. Deteriorating for creeks, rivers and groundwater groundwater quality will have an impact The quality of water in South Australia’s on the ecological communities that creeks, rivers and groundwater is assessed rely on it rather than surface water to against national water quality guidelines. 40 STATE OF THE ENVIRONMENT REPORT 2008 Water Quality • River health assessed according compared to the National Water Quality to the Australian River Assessment Guidelines (NWQG) for the protection of System (AUSRIVAS) freshwater ecosystems. Table 2.1 shows how the data was analysed Provides an indication of the ecological health of rivers and creeks by assessing Nutrient and turbidity data at each site the type and numbers of macroinverte- were ranked from highest value to lowest brates present. value. The 90th and the 50th percentiles, i.e. the median, were then selected from • The condition of wetlands the ranked datasets for comparison with Gives a rating of the condition of the NWQGs. Water quality was classified wetlands across the state. as good, moderate or poor with respect to these indicators according to the criteria shown in Table 2.1: What is the current The proportion of monitoring sites that Whatsituation? is the current situation? were classified as

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