State Water Management Outcomes Plan Order 2002 (NSW)
I, Professor Marie Bashir AC, Governor of the State of New South Wales, with the advice of the Executive Council, and in pursuance of section 6 (1) of the Water Management Act 2000, make the following Order establishing the State Water Management Outcomes Plan.
Dated at Sydney, this 18th day of December 2002.
By Her Excellency’s Command,
Minister for Land and Water Conservation
This Order is the State Water Management Outcomes Plan Order 2002.
This Order commences on 20 December 2002.
The following State Water Management Outcomes Plan is established.
The aim of the Water Management Act 2000 (the Act) is to provide for the sustainable and integrated management of the water sources of the State for the benefit of both present and future generations. The Act provides for the establishment of this State Water Management Outcomes Plan (SWMOP) to set out the over-arching policy context, targets and strategic outcomes for the development, conservation, management and control of the State’s water sources.
This SWMOP is the first of its kind and will have effect for five years from the date of its gazettal. It will then be reviewed and updated.
This SWMOP promotes the objects of the Act and its water management principles, and seeks to give effect to the NSW Government’s salinity strategies. It is also consistent with government legislative obligations, Commonwealth international agreements and government policy. It has had regard to relevant environmental, social and economic considerations, and the results of monitoring and assessment programs.
The SWMOP explicitly provides for the protection and enhancement of the environmental services provided by aquatic ecosystems, while delivering a stronger and clearer framework for the use of water to meet human needs, including more secure access licences. It details the Government’s commitment to effectively manage the important linkages between environment, human health, prosperous communities and profitable industries.
This SWMOP provides clear direction for all water management in New South Wales including (but not limited to) the creation of management plans addressing:
• water sharing,
• water use,
• drainage management,
• floodplain management,
• controlled activities and aquifer interference, and
• environmental protection.
In particular, it seeks to ensure that the NSW Government’s Interim (Water Quality and River Flow) Environmental Objectives for NSW waters are explicitly addressed in future water resource management and action.
Over the last ten years or so, a wide range of policies and inter-government agreements have been developed which set in place principles, standards and processes to ensure better management of the State’s water and related resources, promote rehabilitation of the State’s environmental and social assets, and realise higher returns on each megalitre of water extracted. This SWMOP is grounded in these existing policies but, consistent with the requirements of the Act, it establishes short term targets that will drive the intent of these policies in more specific and tangible ways.
This SWMOP therefore sets both long term outcomes and 5 year management targets for water management. These are based on a principle of continuous improvement in the water-dependent environment and in the social and economic benefits the community receives from its water sources and their dependent ecosystems.
To ensure improvement, management objectives and targets must be responsive and adaptive to improved knowledge and changing social and economic circumstances and values. It is therefore appropriate that the management planning is staged over five to ten year cycles. The SWMOP will therefore be reviewed in five years allowing the subsequent generation and review of management plans to respond to any new directions or priorities.
The outcomes and targets identified in this SWMOP do not attempt to be exhaustive. Instead the focus is on those outcomes which reflect the highest priorities and/or are good indicators of overall improvement. Similarly the targets selected are those which are likely to achieve the greatest gains towards the outcomes in the short term. The targets do not therefore seek to establish an ultimate position or standard but rather to take a significant but practical step in the process of continuous improvement. Such steps will involve consultation with the community concerned and assessment of social and economic impacts.
In a few cases this SWMOP sets what might be termed “enabling” targets. These typically require identification and assessment to be completed within the five years as an essential prerequisite for determining a more specific management outcome. This recognises that in these cases, action cannot be taken in the short term without such information. Where the information is locally available then action should commence earlier.
The outcomes and targets span regulated river, unregulated river, groundwater, estuarine and coastal water sources. They are consistent with the Objects and provisions of Section 3 of the Act. In particular they:
• are in accord with the principles of ecologically sustainable development and will protect and/or restore water sources and their dependent ecosystems,
• seek to prevent declines and make improvements in the ecological health and productivity of water sources,
• promote recovery of threatened species and communities and the management of key threatening processes listed under the under the Fisheries Management Act 1994 and the Threatened Species Conservation Act 1995 (arising from the UN Biodiversity Convention),
• seek to protect and restore habitats, water sources, floodplains and dependent ecosystems,
• seek to protect and restore wetlands listed under the Ramsar Convention, and wetlands of national significance listed in the Directory of Australian Wetlands,
• seek to protect migratory waterbirds listed under the Convention on Migratory Species, and JAMBA and CAMBA agreements,
• seek to protect the Aboriginal customary and contemporary ties to water,
• seek to halt or reverse the decline in key water quality parameters,
• will foster social and economic benefits to the State,
• will foster benefits to Aboriginal people in relation to their spiritual, social customary and economic use of land and water,
• provide greater certainty and flexibility in the exercise of access rights,
• encourage water to move to higher value use,
• encourage water to be managed and used efficiently, and
• optimise the economic value of water diverted from water sources and encourage best practice in its use.
In 1999, as part of its Water Reform package, the NSW Government worked closely with the community to develop Interim Environmental Objectives for Water Quality (WQOs), and River Flow (RFOs) for each catchment in New South Wales. Longer term objectives have been set for some individual catchments through Healthy Rivers Commission inquiries.
The Interim Environmental Objectives identify the broad goals to achieve long-term river health, maintain biodiversity and secure sustainable water sources for communities and industries dependent on water of a certain quality. Water quality objectives are based on measurable environmental values that provide the appropriate water quality for environmental and human-related needs. River flow objectives aim to improve and maintain river health by recognising the importance of natural river flow patterns in managing the riverine water sources.
The Interim Environmental Objectives are designed to support a range of values identified by the community, including:
Water Quality Objectives (WQOs)
WQO 1 | Aquatic ecosystems |
WQO 2 | Visual amenity |
WQO 3 | Secondary contact recreation |
WQO 4 | Primary contact recreation |
WQO 5 | Livestock water supply |
WQO 6 | Irrigation water supply |
WQO 7 | Homestead water supply |
WQO 8 | Drinking water at point of supply—Disinfection only |
WQO 9 | Drinking water at point of supply—Clarification and disinfection |
WQO 10 | Drinking water at point of supply—Groundwater |
WQO 11 | Aquatic foods (cooked) |
River Flow Objectives (RFOs)
RFO 1 | Protect pools in dry times |
RFO 2 | Protect natural low flows |
RFO 3 | Protect important rises in water levels |
RFO 4 | Maintain wetland and floodplain inundation |
RFO 5 | Mimic natural drying in temporary waterways |
RFO 6 | Maintain natural flow variability |
RFO 7 | Maintain natural rates of change in water levels |
RFO 8 | Manage groundwater for ecosystems |
RFO 9 | Minimise effects of weirs and other structures |
RFO 10 | Minimise effects of dams on water quality |
RFO 11 | Make water available for unforeseen events |
RFO 12 | Maintain or rehabilitate estuarine processes and habitats |
The Water Management Act 2000 requires the SWMOP to be consistent with these Objectives, and states that all management plans developed under the Act should be consistent with government policy in relation to environmental objectives for water quality and river flow.
The Interim Environmental Objectives for Water Quality and River Flows should therefore be considered when assessing progress against the long term objectives and 5 year management targets set in the SWMOP. In cases where longer term objectives have been set through the Healthy Rivers Commission, these individual objectives should be considered.
All management plans developed under the provisions of the Water Management Act 2000 will be framed to be consistent with those targets that are relevant to a particular plan, and to the longer term outcomes, and should indicate the degree to which they will contribute to them. The degree to which each water management area should contribute to the achievement of a State target will depend upon:
• the degree to which the target is relevant to the area,
• the social and economic impacts,
• the relative management priorities, risks and costs, and
• the relative environmental importance.
In assessing the adequacy of any management plans prior to endorsement, the Minister will need to, in consultation with the Minister for the Environment, take into account the degree to which the management plan has addressed the relevant outcomes and targets.
Some water sources may already be better than a particular target while others which are currently below target, may seek to go measurably beyond it within the 5 years. Some water sources that are significantly below a SWMOP target, may achieve a positive result in moving towards the target but, in falling short, will need to seek further improvement in future planning cycles. In all cases, such action would be consistent with the principle of continuous improvement and, subject to appropriate cost for benefit considerations, will be supported as being consistent with the SWMOP.
Section 9 of the Act requires that all functions exercised under that Act must be in accordance with this SWMOP. This is a wide-ranging requirement and will affect much of the day-to-day work of the Department of Land and Water Conservation (DLWC) and others exercising functions on its behalf. For example, care must be taken to ensure that licences and approvals do not detract from the achievement of the SWMOP outcomes and targets, but as far as possible, positively contribute towards their achievement.
This SWMOP is expected to:
• improve the quality of water sources and the health, productivity and diversity of their dependent ecosystems,
• increase the economic value of water extracted from water sources and used, and
• protect the long term interests of regional communities.
The implementation of management plans may result in transitional impacts and the Government may provide guidance on arrangements and assistance to help affected parties overcome any short term problems.
Monitoring compliance with the requirements of management plans, benchmarking and assessing changes in the state of our water ecosystems and in the economic and social factors influenced by water management actions, is clearly an essential component of the cyclic management planning established by the Water Management Act 2000.
It is therefore required that water management provides for the collection of information which will allow:
• assessment of performance against the management targets,
• assessment of social and economic impacts, and
• benchmarking of current conditions and evaluation of future trends in respect to the long term outcomes.
A performance assessment strategy covering these three aspects will be established within six months of the gazettal of this SWMOP.
Management plans developed under the Water Management Act 2000 should provide for the monitoring of performance of relevant local management targets and this information will be collated and reviewed to assess performance against the SWMOP targets. The Minister may provide guidance on objectives, strategies and performance indicators for this purpose (as required in a management plan under Section 35 (1) of the Act). The monitoring and assessment of the long term outcomes, however, will be designed and undertaken through statewide programs and targeted local activities which ensure that sampling and analysis is carried out at a scale and density appropriate to deliver meaningful and cost effective information.
Several programs are already in place to monitor the physical, chemical and biological status and response of aquatic systems (eg. Integrated Monitoring of Environmental Flow (IMEF), fish, wetlands and waterbird surveys). Other programs provide social and economic data relevant to the analysis of social and economic responses to water management. Performance monitoring for this SWMOP will build, as far as possible, on these existing programs.
Primary ecological production maintained or improved, including:
(a) carbon cycling,
(b) production to respiration ratios, and
(c) carbon and food fluxes between rivers and floodplains, estuaries and coastal waters.
Degraded wetlands improved and those listed as wetlands of national or international significance protected and restored.
The diversity and abundance of native aquatic animals and plants protected and restored by addressing the cumulative impacts of water management on their habitats and life cycles. The status of aquatic communities to be informed through but not limited to:
(a) the abundance and diversity of invertebrate populations improved,
(b) native fish populations within their native range increased and the ratio of alien to native fish species reduced,
(c) colonial waterbird breeding opportunities increased,
(d) estuarine prawn populations improved, and
(e) the status of threatened species populations and ecological communities improved.
Water supplies necessary to maintain or improve the health and well being of rural and urban communities assured.
Aboriginal traditional and contemporary dependencies on, and cultural association with water protected and improved. In particular:
(a) economic access to water increased,
(b) cultural and customary associations with water protected,
(c) opportunities for learning and information improved, and
(d) capacity for Aboriginal people’s involvement in water management increased.
Incidents of blue green algal blooms affecting essential water supplies and recreational values reduced.
The productive capacity of land and water maintained. In particular:
(a) rate of land degradation associated with irrigation activities reduced, and
(b) rate of increase in river salinity levels reduced.
Water use efficiency increased.
The economic efficiency of investment in water industries improved.
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Many of the rivers and floodplains of NSW have been modified and used to provide a range of important social and economic benefits. The water is diverted for town water, manufacturing and irrigation, the fertile floodplains are farmed and, in turn, support numerous towns and transport routes. Similarly aquifers and the ecosystems which depend on them have been impacted by water extractions, mining, and by the infiltration of pollutants.
As rivers are increasingly modified, not only is their ecological character changed but the basic health of the river becomes compromised. Generally the more developed the river, the less natural it becomes and the less healthy it is. This is because the changes we impose on the river and its environment affect the basic ecological functions and values (or services) that a natural river would provide such as: the provision of clean water, energy production, nutrient cycling, and sustaining river and coastal fisheries and water bird habitats and populations.
A useful concept is that of a “healthy working river” (CRC for Freshwater Ecology in Watershed, February 2002; Hillman
This is also the basis of the Water Management Act 2000. A principle of the Act is to maximise the social and economic benefits to the community. However, other principles emphasise the importance of protecting and restoring water sources and floodplains, and the habitats, animals and plants that depend on them. Specifically, the Act requires that in sharing water, the highest priority is to protect the water source and its dependent ecosystems.
Many rivers and aquifers are now being used at a level that is likely to result in ongoing deterioration in environmental health. This decline in health, when fully realised, is likely to be unacceptable to this generation and potentially disastrous to future generations. It is critically important to minimise existing impacts and in many cases actively attempt to reinstate key ecological processes and biodiversity.
(1) Primary ecological production maintained or improved including: (a) carbon cycling, (b) production to respiration ratios, and (c) carbon and food fluxes between rivers, floodplains, estuaries and coastal waters
The development of our water sources, including floodplains, estuaries and coastal waters has resulted in significant damage to the natural ecology of these areas and declines in the diversity of both habitats and species.
The strategic goal of the NSW Biodiversity Strategy is to “Protect the native diversity of NSW and maintain ecological processes and systems”. Healthy functioning ecosystems are fundamental to the continuing survival of plant and animal species and to the human communities and economies that depend upon them. The movement of water, the transported sediments and nutrients, and the wetting and drying cycles profoundly affect the ecology and productivity of an aquatic or semi-aquatic system. Water movement affects how energy (mainly in the form of organic carbon) flows through the system, the nature of interactions between organisms in the food web, and the ecology and life strategies of those organisms.
Flow regimes, fluctuating water levels and intermittent floodplain inundation all play critical roles in:
• determining habitat availability and condition,
• connecting aquatic and floodplain ecosystems,
• food production (eg biofilm—bacteria and algal communities living on rocks and logs, plankton—microscopic plants and animal succession),
• carbon cycling,
• the ratio of production to respiration,
• stony bed scouring, and
• species dominance and competition.
Structural damage to rivers, riparian zones and floodplains, as well as the proliferation of barriers to flow and to the movement of aquatic fauna, and the construction of drains are all potentially detrimental activities. They can reduce the diversity and quality of available habitat, interfere with the hydraulic connection between habitats and disrupt food chains. Water extraction from rivers and aquifers has also had an impact by changing the patterns and frequency of wetland inundation, reducing wetland productivity and altering the frequency of food and energy exchanges between wetlands and rivers.
Water pollution, in particular high acid discharges, high salinity and low oxygen levels, can also impact on ecological processes and threaten individual aquatic species.
All of the above factors need to be addressed in an effective water management regime if the health and productivity of water dependent ecosystems are to be maintained and/or improved.
In recent years increased scientific effort has been focused on understanding the basis of ecological primary production and on developing predictive flow response models. The “Integrated Monitoring of Environmental Flows” (IMEF) program covers a number of such indicators, for example, carbon cycling, biofilm production and stony bed scouring. There is a need to continue and expand this effort to help us understand the long term trends in the basic functioning of aquatic ecosystems.
(2) Degraded wetlands rehabilitated and listed wetlands of national or international significance protected or restored
In NSW there are about 4.6 million hectares of wetlands ranging in type from mangroves, saltmarshes, seagrasses and coastal brackish wetlands, to inland freshwater and floodplain wetlands, backswamps, billabongs, large terminal wetlands, ephemeral claypans and salt lakes. Many wetlands depend on river flows for their water supply. Of the 6.3 million hectares of wetlands estimated to occur in the whole Murray-Darling Basin, over 90% are floodplain wetlands. Some of these wetlands are dependent on groundwater levels to create and/or maintain wetted areas.
Wetlands are vitally important to the environmental health of rivers and estuaries by providing unique habitats for a diverse range of plant and animal species; making important contributions to biodiversity; providing nursery and breeding grounds for many aquatic and semi-aquatic species; improving water quality; providing essential sources for biological productivity and nutrient recycling; mitigating floods; protecting foreshores, and increasing groundwater recharge.
Wetlands are often important cultural sites for Aboriginal people. This importance is due not only to a spiritual connection to these places, but also to their ongoing value as places of cultural learning and resource use.
Unfortunately many wetlands have been substantially degraded by a range of activities, many of which are related to water use and development such as:
• reduction in the frequency, extent and duration of inundation,
• reduction in the hydraulic connection between wetlands and the river or other water sources through construction of physical barriers,
• poor land management practices,
• artificial drainage,
• tidal barrages,
• filling of wetland depressions for urban or agricultural development, and
• modification into permanent water storages.
The NSW Wetlands Policy was released in 1996 and seeks, through its associated wetland action plans, to provide clear guidance on the protection, rehabilitation and wise use of wetlands. While it has supported a range of wetland initiatives through associated educative programs and financial grants, there is still substantial effort required to generally restore wetland functions and rehabilitate key wetlands.
Water management needs to specifically address the rehabilitation of at least a proportion of the degraded wetlands in each water management area. This may require:
• identification of wetlands in the management area,
• restoration of conditions known to favour native plant species in wetlands,
• reconnection of wetland with the relevant water source through removal, modification or periodic opening of floodplain barriers and flood gates,
• improvement in the frequency and duration of inundation—which may involve better groundwater level management, increased flow frequency in the relevant high flow range, and reduced impact from unseasonal regulated supply flows,
• improvement or reduction in the rate of decline in water quality—particularly nutrients and salt in freshwater water sources, and
• improved land management practices.
Some wetlands in NSW have been recognised as having particular national or international significance because they are relatively rare or are good representatives of their type, or they may provide important habitat for nationally or internationally recognised or endangered animal and plant species or communities. Examples of these significant wetlands are those:
• listed under the Ramsar Convention,
• listed in the Directory of Australian Wetlands, and
• providing significant habitats for migratory waterbirds listed under the Convention on Migratory Species, and the JAMBA and CAMBA Agreements.
NSW has a particular responsibility to ensure that these wetlands are, as far as possible, restored and protected from further damage. There is a range of mechanisms available to help achieve this including voluntary conservation agreements with landholders; plans of management under the Environmental Protection and Biodiversity Act 1999 for Ramsar wetlands; general environmental flow provisions; and flows targeted specifically at the listed wetland.
A number of monitoring programs have been established which can help inform the assessment of wetland status. These programs include the IMEF program and the NPWS wetland mapping program. There have been detailed surveys of some freshwater and coastal wetlands including seagrasses, mangroves and saltmarshes but there has been no comprehensive monitoring across NSW.
(3) The diversity and abundance of native aquatic plants and animals protected and restored by addressing the cumulative impacts of water resource management on their habitats and lifecycles. The status of aquatic communities to be informed through, but not limited to, the following indicators: (a) abundance and diversity of invertebrate populations improved, (b) native fish populations increased within their natural range, and the ratio of alien to native fish species reduced, (c) increased colonial waterbird breeding opportunities and abundance and diversity of other water-dependent vertebrate species, (d) estuarine prawn populations improved, and (e) the status of threatened species, populations and ecological communities improved
The continuing loss of biodiversity is an issue of state and national concern and has been identified as perhaps our most serious environmental problem. Despite many advances in understanding and awareness, and increased efforts to conserve biodiversity in recent decades, ecosystems continue to be degraded. There is now a growing recognition that we have been under-investing in biodiversity conservation and we have failed to effectively manage activities that threaten biodiversity. Without further investment in biodiversity conservation, serious long-term ecological and economic consequences may result.
Biodiversity has many values. At the most fundamental level, biodiversity is the basis for healthy, functioning ecosystems. Biodiversity is also essential to allow adaptation to changing environmental circumstances such as climate changes. In addition, biodiversity is essential to maintain the habitats and food webs that support many of the species on which we (and other animals) depend. Put simply, biodiversity provides all the critical processes that make life possible. We gain enormous benefits from these processes, but they are often grossly undervalued.
Aquatic biodiversity provides many direct economic and social benefits. Economic benefits include the provision of valuable food (fish and shellfish), industrial materials, and the means to control some pest species and diseases. Some examples of these economic benefits are:
• a significant contribution to the gross value of Australian commercial fisheries production (in 1999–2000 this was $2.32 billion—ABARE 2001). Invertebrate species such as prawns, lobsters and pearl oysters accounted for two-thirds ($1.56 billion) of this total,
• recreational fishing and tourism on inland waterways are a mainstay of the economy of many small towns. An estimated 20 percent of the population, representing over 1 million people, go fishing each year in NSW,
• it has been estimated that the average hectare of mangrove habitat could be worth $8,000 annually in fish production, and
• the tourism value of large wetland areas such as the Macquarie Marshes and the Gwydir wetlands is growing rapidly.
The conservation of biodiversity also has social benefits. Aboriginal people have depended upon aquatic and water dependent species not only traditional and contemporary food and medicine resources but also as the basis of broader cultural association through totem species, ceremonies and dreaming stories.
In addition to the biological resources we already use, aquatic biodiversity represents a pool of untapped opportunities, a ‘storehouse’ of genetic and chemical material that could provide the future foundation for new technologies in the pharmaceutical and other industries.
There is also growing community recognition of the intrinsic value of biodiversity, acknowledging the inherent right of all species to exist, regardless of their value to humans. Australia’s aquatic biodiversity is valued not only by Australians but also internationally for its richness and uniqueness.
There is also growing community recognition of the intrinsic value of biodiversity, acknowledging the inherent right of all species to exist, regardless of their value to humans. Australia’s aquatic biodiversity is valued not only by Australians but also internationally for its richness and uniqueness.
Objective 4.7 of the NSW Biodiversity Strategy requires the “effective management of water resources to conserve biodiversity and meet environmental, economic, social and community needs”.
In order to protect or improve aquatic biodiversity, it is important to ensure that, as far as possible, water management addresses the full spectrum of habitats and the differing requirements of all species within an ecological community but which must coexist in order to ensure the health and survival of the whole. For practical purposes, the status and diversity of an ecological community may be reasonably informed through a number of indicator or key species. This SWMOP therefore adopts four key indicator groups (a–d) together with any listed threatened water-dependent species, populations or communities.
(a) abundance and diversity of invertebrate populations improved
Aquatic invertebrates are animals without backbones, which live at least part of their life within the water column or substrate of an aquatic environment.
Invertebrates play a very important role in aquatic ecosystems, by breaking down organic matter, transforming nutrients, and feeding on fungi and algae to provide a major food source for higher order animals such as fish and waterbirds. A healthy aquatic ecosystem often supports a wide range of invertebrate species, reflecting a diversity of food sources and a diversity of habitat types. Abundant populations of invertebrates will ultimately be reflected in the abundance of the fish, reptiles and waterbirds that feed upon them.
Aquatic invertebrate communities can be impacted by changes in both water flow and quality. In upper and mid sections of rivers, the reduction in the frequency of freshes and floods reduce the frequency of bed disturbance and so the “resetting” of benthic (ie bottom-dwelling) invertebrate populations is less frequent. This is likely to lead to a less diverse fauna, with the biomass dominated by a small number of species. Reduced flushing will lead to clogging of coarse riffle substrates, with fine sediments and organic matter reducing the amount and quality of the benthic habitat.
The changes in the invertebrate communities in lowland rivers are largely due to habitat alteration rather than direct flow effects on the organisms. Reduced flow variability, reduced habitat diversity due to snag removal, bank slumping and loss of littoral vegetation, changes in substrate, changes in water temperature and the predominance of slow turbid flows in weir pools etc have all contributed to changes in invertebrate diversity and abundance.
Invertebrates are considered so fundamental to ecosystem health and production that a national effort, the Australian River Assessment System (AusRivAS) is underway to monitor river health using measurements of aquatic macroinvertebrate communities. This program uses the environmental attributes of a river reach to predict the kinds of macroinvertebrates that would be present in the reach if the river was “healthy”. The difference between the predicted species and those actually collected from the reach over time provide an index of river health.
(b) native fish populations increased within their natural range, and the ratio of alien to native fish species reduced
Over the last 100 years the abundance and distribution of native fish including many commercial and recreational species (eg Murray cod, golden perch, silver perch, catfish, and Macquarie perch) have declined markedly in many of the State’s surface water sources. Eleven fish species and two endangered populations are currently listed as threatened under the Fisheries Management Act 1994.
These declines have been attributed to a range of factors including:
• general habitat degradation,
• altered river flows,
• introduction of alien fish and diseases,
• interrupted migration pathways,
• reduced water quality and pollution,
• overfishing, and
• changed energy fluxes.
A lack of detailed information on the habitat associations and requirements of most native fish and on the impacts of alien fish species means the relative significance of these factors is unknown. Furthermore their relative influence will almost certainly vary substantially from water source to water source. Nevertheless, altered flow and sediment regimes have had a dramatic impact on fish populations including removal of spawning and migration cues, reduced dispersal and recruitment, reductions in aquatic vegetation and habitat connectivity, increases in siltation, reduction in water quality and reductions in habitat diversity. The imposition of barriers to fish passage has also been a major factor in the decline in fish in many water sources.
A large-scale systematic survey of riverine fish in the New South Wales part of the Murray-Darling Basin was undertaken in 1996/97 (Gehrke
More recently, the draft Murray-Darling Basin Native Fish Management Strategy documented that:
• only 10 percent of pre-European native fish populations remain in the Murray-Darling Basin, and
• native fish make up only 4 percent of the total catch in the Murray.
Native fish are also a reasonably good long term indicator of the general health of rivers as they are sensitive to the loss of a wide range of instream and wetland habitats. They are also highly dependent on food supplies from both instream and floodplain sources. Many native species require periodic floodplain or wetland inundation to trigger spawning and ensure the successful recruitment of juveniles. For many marine species the trigger is the amount of fresh water that moves offshore to the adult populations. Many species migrate or disperse over reasonable distances, often between rivers and estuaries, and are therefore sensitive to barriers and flow conditions.
Habitat structure and diversity, which is a function of hydrology and hydraulics, as well as of geomorphic elements such as riffles, runs and pools, sediment types and snags, is a major factor determining the species composition and abundance of fish communities.
There are in excess of 12 alien fish species present in rivers across the State, mostly as a result of deliberate introductions dating from the mid-1800s. Of these carp, goldfish, gambusia and redfin perch are the most widespread, and carp is the species that has caused the most ecological damage.
Rivers whose flow regimes have been significantly modified commonly exhibit both a decreased native species diversity and a proliferation of alien species. There is substantial evidence to show that river regulation has favoured carp at the expense of native species. Because native fish have reasonably specific flow requirements for reproduction and the successful recruitment of juveniles, reductions in flow variability reduces the abundance of those species. Carp, on the other hand, have less specific flow requirements, as reproduction is not cued by seasonal flow conditions, and successful recruitment is less dependent on specific flow conditions. Although the levels of scientific evidence vary substantially, declining native fish populations, blue-green algal blooms, increased turbidity and lost aquatic vegetation have all been attributed to some degree to the proliferation of carp.
The ratio of alien to native species in the rivers has been found to be a useful index of the health of a river as it reflects the relative advantage that changes in river condition and particularly flow gives to alien over native fish species. It also provides an indicator of the degree of pressure that alien fish species themselves place on the system.
(c) increased colonial waterbird breeding opportunities and abundance and diversity of other water-dependent vertebrate species
Colonially breeding waterbirds (ibis, egrets, herons, spoonbills and cormorants) breed in large colonies on a relatively few wetlands supplied by rivers in New South Wales (eg Macquarie Marshes, Gwydir wetlands, Barmah Millewa Forest, Booligal wetlands). The strongholds of remaining breeding areas in Australia are primarily concentrated in the surface water sources in New South Wales. For example, the Macquarie Marshes is the most important site (in terms of the numbers of breeding birds and/or the frequency of breeding and range of species) for colonially breeding waterbirds in Australia. The breeding of colonial waterbirds is closely linked to the flooding of inland surface water sources. The area available for breeding waterbirds to forage appears to be a critical factor for breeding. Breeding success is also closely linked to the size of floods with much greater reproductive success during larger floods than smaller floods. The regulation of rivers with dams and extraction upstream of major wetlands has severely affected the breeding of colonial waterbirds. It has been calculated that extraction of water from the Macquarie River reduced breeding by 100,000 pairs in the Macquarie Marshes every 11 years.
There has been inadequate attention to the importance of aquatic habitats for other vertebrate groups such as amphibians, snakes, lizards and mammals. The abundance and diversity of these groups must be considered explicitly in management decisions.
(d) estuarine prawn populations improved
River discharge and estuarine productivity are closely linked. Fluctuations in salinity, turbidity, and nutrients can affect the extent of available habitat and the productivity of the estuary. Lonergan and Bunn (1999) and previous work by Glaister (1978), and others have confirmed that high river discharges can have a strong positive effect on the production of commercial and recreational coastal fisheries, especially on prawns.
Catches of school prawns in the Hunter River and Clarence River showed that each year following major rainfall, productivity increased (Ruello 1973; Glaister 1978). These increases are thought to be linked to secondary effects of rainfall such as reduced salinity and turbulence which stimulates the migration of juvenile prawns from nursery habitats in estuaries and rivers.
Lonergan and Bunn (1999) have also observed similar results in longer-lived species such as mud crabs and flathead. The catches of prawns are likely to be related to increased juvenile productivity, as the time delay between when the rainfall event occurs and when the juveniles enter the fishery is in the order of only six months. Therefore, while the influences on increased productivity of these species require further investigation, prawn productivity is a useful short-term biological indicator of the linkage between river flow and estuarine productivity.
(e) the status of threatened species, populations and ecological communities improved
The State’s rivers, lakes, estuaries and wetlands form complex biological systems that support a rich diversity of plant and animal communities. However, some of these animals and plants are facing threat of extinction as the State’s aquatic systems undergo dramatic changes due to factors such as reduced or modified flow regimes, loss of riparian vegetation and habitat diversity, and declining water quality. The number of threatened animals and plants is continuing to grow.
Objective 2.4 of the NSW Biodiversity Strategy requires the State to “Implement mechanisms for the identification, recovery, and rehabilitation of threatened species, populations and ecological communities and protection of critical habitats”.
The Threatened Species Conservation Act 1995 and the Fisheries Management Act 1994 aim to stop the decline in biological diversity by promoting recovery of species, populations and ecological communities and eliminating or managing threatening processes.
Both Acts provide for the listing of animal and plant species according to their status. Once listed a recovery plan must be prepared within 3 to 5 years, depending on the listing. These plans will be comprehensive documents that outline future management actions to encourage the recovery of species. Primary recovery actions generally aim at stabilising population numbers and halting habitat deterioration. Further actions may aim at rebuilding populations and conserving further habitat. Complementary to the recovery planning process is the management of key threatening processes through a process of threat abatement planning.
The on-going management of aquatic systems must seek to reduce the decline in biological diversity by ensuring activities and management plans are consistent with the objectives and recommendations of recovery plans and threat abatement plans. Additionally, high conservation values and areas that possess special requirements for threatened species or communities, should be maintained or improved for conservation purposes.
Recovery and threat abatement planning for many species, populations and ecological communities, and key threatening processes are still in the initial stages. In the absence of such plans and identified conservation values and areas, effort should be focused on preserving or restoring ecological processes and on maintaining and restoring the known flow or habitat requirements of better known key species. Since these species are sensitive to change, their conservation becomes a benchmark for other species about which less is known.
For all threatened species, populations and ecological communities, the paucity of information and the need for more research on life history, habitat requirements, distribution and threatening processes directs a need to adopt a precautionary approach to water management.
The NSW Government is responsible for ensuring that the requirements of threatened species, populations and ecological communities, critical habitats, key threatening processes and their associated plans are addressed in the development of all plans and individual resource management decisions.
NSW society and its local communities will be the ultimate beneficiaries of more sustainable water management. Improved environmental outcomes will ensure that current and future generations will be able to enjoy the benefits of our natural heritage and the essential services that the water-related ecosystems provide. Improved economic certainty, water use and investment efficiency, and water trading and dealing opportunities will ensure more productive water use and improved economic returns. In addition to these, water source planning and management must ensure that the basic needs of the community continue to be met. This includes the right to essential domestic and stock water supplies whether within a town or rural setting, which are not compromised by other economic demands, and reasonable opportunities to enjoy the recreational, aesthetic, cultural and spiritual values provided by water sources and their associated environments.
(1) Water supplies necessary to maintain or improve the health and wellbeing of rural and urban communities assured
An owner or occupier of a landholding is entitled under the Water Management Act 2000, without the need for an access licence, water supply work approval (for works excluding instream dams or weirs) or water use approval, to take water from any river, estuary or lake, to which the land has frontage or from any aquifer underlying the land. This basic rights provision is to meet normal domestic requirements and non-intensive stock watering.
The Water Management Act 2000 requires that these basic rights be protected from the impact of other extractions. It also specifies that town water supply (local water utilities) must have priority to water from rivers and aquifers over other licensed uses.
Human and stock drinking water is also being increasingly threatened by water quality problems which, at worst, can impact on the health of stock or the people dependent on the contaminated water source and, at best, can substantially increase the costs associated with water treatment or alternate supplies for rural land-holders and communities.
Many indigenous communities, in particular, rely on bores, local dams and river pumps for their water supplies. Significant resources are spent on setting up and maintaining this infrastructure and yet, in spite of this, both the quality and quantity of the water supplied to many communities remain inadequate. This is contributing to the poor health and living standards of those communities.
Salinity is now recognised as one of the greatest threats to water supplies for rural communities within the Murray-Darling Basin. At Dubbo, on the Macquarie River, the water currently exceeds the World Health Organisation (WHO) guidelines for the acceptable taste of drinking water (800 EC) 6 percent of the time. This is predicted to increase to over 80 percent of the time by 2100, unless the trend can be managed.
(2) Aboriginal traditional and contemporary dependencies on, and cultural associations with water protected and improved. In particular: (a) economic access to water increased, (b) cultural and customary associations with water protected, (c) opportunities for learning and information exchange improved, and (d) capacity for Aboriginal people’s involvement in water management increased.
For over 50,000 years, Aboriginal people have been living in and around Australia’s rivers, floodplains, billabongs, marshes, swamps, lakes and mud flats and depending upon these water sources for basic survival. These water sources also have cultural relevance. Food was obtained from rivers (fish, crustaceans, oysters etc.), the floodplain (grasses, tubers, fruits etc.) and associated wetlands (kangaroo, emu, birds, snakes etc). Vegetables, fruits and traditional medicinal plants are most often sourced from or near waterways.
Major waterways, and most other water sources, in NSW continue to have cultural relevance to Aboriginal people and are often associated with dreaming stories and cultural learning that are still passed on. Cultural learning through dreaming stories teaches Aboriginal people who they are and where they belong. Many ceremonial rites are linked with water and impart knowledge of how to continue a respectful partnership with water and all the creatures that use it. For these reasons, an object of the Water Management Act 2000 is to recognise and foster the benefits that result from the sustainable and efficient use of water, including the benefits to Aboriginal people in relation to their spiritual, social, customary and economic use of land and water.
This target is relevant to management plans under Part 3 of the Water Management Act 2000 dealing with: Division 4—Drainage management, Division 5—Floodplain management, Division 6—Controlled activities and aquifer interference activities, Division 7—Environmental protection.
Coastal floodplains and wetlands in NSW are subject to frequent flooding. Governments have sought to mitigate flood impacts through drainage, river redesign, levees and floodgates to allow this land to be used as productive farming and urban areas. This has resulted in the loss or alteration of wetlands, and changed vegetation on floodplains and wetlands from flood-tolerant to flood-intolerant species.
These areas are also underlain by brackish water sediments that contain iron sulfide minerals. When beneath the watertable, these soils are benign. However, if over-drained either during naturally dry conditions or artificial drainage, the sulfides oxidise and form sulfuric acid. These soils, known as acid sulfate soils, can also mobilise aluminium, iron, manganese and other heavy metals, creating a toxic environment for aquatic species, and have been linked to many fish kills in the past.
Changed land management of coastal floodplains has also resulted in the generation of “black water”, low in dissolved oxygen, which is very detrimental to aquatic fauna. This was typified by the major fish kills during the 2001 floods in the Macleay, Clarence and Richmond Rivers where rapid drainage of low dissolved oxygen water created from decaying flood-intolerant vegetation on the floodplain, and mobilisation of iron mono-sulfide black sludge in drains where acid sulfate soils were present, caused dissolved oxygen levels to fall rapidly for several weeks.
In 2000 the NSW Government announced the Acid Sulfate Soils Hot Spot Program which seeks to rehabilitate priority hot spots in coastal floodplains. Two million dollars has been allocated for the first two years to target on-ground changes in of seven major hot spots. At the same time it is important that the acid drainage from these hot spots does not increase as a result of new development or activity. The potential for applying an offset scheme to prevent and, if possible, reduce any acid drainage should be investigated. This would need careful consideration to ensure that the intended environmental outcomes are achieved.
At the same time, additional work is required to assist landholders to improve the management of coastal floodplains and minimise the risk of new hot spots developing. Drained wetlands and backswamps must be managed differently to reduce the risk of chronic acid sulfate soil and black water discharges following rainfall events. The first step will involve mapping high-risk drained wetlands and then working with landholders to reduce these risks. This may require modifications to drainage, watertable management, rehabilitation of wetland vegetation and other techniques.
This target is relevant to management plans under Part 3 of the Water Management Act 2000 dealing with: Division 3—Water use, Division 4—Drainage management, Division 5—Floodplain management, Division 6—Controlled activities and aquifer interference activities, Division 7—Environmental protection.
Urban stormwater is the rainfall runoff from the impervious surfaces and shallow rooted lawns dominating urban areas. The unnaturally high volume and velocity of runoff following rainfall events and the consequent reductions in low and/or baseflows, can pose significant environmental risks to the receiving rivers and estuaries.
Storm runoff can also wash large loads of pollutants from the urban surfaces into urban drains and creeks that find their way into the rivers and estuaries. Urban runoff can be significant source of the phosphorus and nitrogen that contributes to algal blooms, and of harmful pathogens (with their consequent risks to human health).
There are many options for better managing urban stormwater and these are currently being developed and explored through the preparation of plans, and managed through the preparation and implementation of integrated urban water cycle management principles. Such solutions include:
• increased retention time for storm runoff through the replacement of engineered drains and pipes with more natural watercourses,
• retention and infiltration of runoff in selected basins and artificial wetlands,
• collection and reuse, and
• higher quality runoff collected and used for groundwater recharge.
The Urban Stormwater Program was originally established as part of the 1997 Waterways Package. It was evaluated by the Stormwater Trust Board and extended for the 2002/3 financial year. The next phase of the Urban Stormwater program will focus on further enhancing the capacity of local councils to manage urban stormwater in an environmentally responsible manner.
The bulk of the grants in the initial program were to local councils and this partnership arrangement continued into the second stage of the program to ensure delivery of improvements in flow regimes and water quality using local knowledge and resources. This will be done through local government plans relating to stormwater, guided by integrated urban water cycle management guidelines currently being finalised by the NSW Government.
Projects funded under this program have focussed on water quality improvement, although recent projects have also sought to reduce the volume and velocity of runoff in recognition of the environmental significance of the flow regime in urban waterways.
This target is relevant to management plans under Part 3 of the Water Management Act 2000 dealing with: Division 3—Water use, Division 4—Drainage management.
The Planning and Management Guidelines for Water Sensitive Urban Design define water sensitive design as “a new approach based on the premise that as easily available water resources become limited and the capacity of receiving environments to accept more waste decreases, conventional water supply, sewerage disposal and discharge systems cannot be sustained in the long term”. At the same time continuation of significant housing development on the fringe of Sydney and other urban centres places the rivers and estuaries under increasing stress as a result of growing demands for water supplies and increased urban storm runoff.
However, these problems can be reduced through good urban planning and water sensitive urban design including for example:
• effective water demand management including greater use of water efficient devices,
• recycling or reuse of wastewater,
• increased use of on-site storage and reuse of stormwater eg rainwater tanks,
• reductions in the area of impervious surfaces directly connected to drainage systems,
• increased use of absorbent surfaces or infiltration zones in driveways and along roadways etc,
• replacement of lawn areas with low water demand landscapes,
• localised water supplies for irrigation purposes, and
• rehabilitation of natural watercourses to increase their capacity to retain and absorb storm runoff.
While water sensitive design is most effective when implemented early in the land use planning and development process, many elements can be retrofitted into existing urban areas particularly as part of urban renewal projects. Water sensitive design measures do not have to significantly increase the cost of development. A recent case study of an urban development site in Brisbane included a comparative assessment of “conventional” and “water sensitive” design approaches. It found that the water sensitive design could provide:
• the same lot yield at approximately the same capital cost,
• maintenance costs which were only marginally higher than conventional designs,
• equivalent, if not superior, marketable values and return on investments,
• offsite environmental impacts that were significantly less than those for conventional designs, and
• more functional and attractive open space.
This target is consistent with the Integrated Water Cycle Management and Stormwater Management programs being implemented by local councils. In fact, the increased adoption of water sensitive designs should improve the effectiveness of capital expenditure on stormwater management and sewer overflows.
It will also complement a range of urban water management targets (Targets 17, 19, 29 and 31) in helping to reduce the growing impact of urban water demands, effluent and stormwater on the State’s water sources.
This target is relevant to management plans under Part 3 of the Water Management Act 2000 dealing with: Division 3—Water use, Division 4—Drainage management.
The Water Management Act 2000 requires land degradation to be taken into account when assessing irrigation developments and water use approvals. Assessment of the risk will be fundamental to the development of management plans dealing with the use of water. The application of water to land can be managed to minimise deep drainage and saline discharge.
Detailed mapping of areas prone to irrigation salinity, to improve the information base on which decisions are formulated, is recommended in the NSW Salinity Strategy, as are activities to reduce accession, through efficient and effective use of water. Without reducing accessions, the risk to the aquatic environment and agricultural production will continue to increase.
This target will contribute to the actions necessary to slow the rate of increase in salinity levels in watercourses (as sought under Target 36). Importantly, it will contribute to maintaining the productive value of irrigated land. This target will be supported by improved water use efficiency.
Despite mapping of depth to watertable in some areas and development of catchment scale salinity predictions in other areas, mapping of zones at risk from irrigation salinity has not progressed far. It is important to establish cause and effect at a sub-catchment level and prioritise actions to reduce accessions to the watertable from irrigation. Accessions are a function of the water applied, weather conditions and crop water uptake. Irrigation salinity occurs where water is not applied efficiently to replace the soil moisture deficit or supply crop requirements, including minimal leaching fractions. Environmental assessment of irrigation developments and their suitability at that location will continue to support this target, especially under Part 5 of the Environmental Planning and Assessment Act 1979, a process which is now supported by the use approval process in the Water Management Act 2000. The Sustainable Agriculture Policy also supports this target.
The rate of accession can be calculated from volume of water applied (metered extractions as a default), effective rainfall (ie. rainfall minus evaporation), crop type and area of crop grown. Where it is difficult to calculate accession rates, it may be preferable to monitor increases in area of irrigation in areas of high irrigation salinity risk. Calculations of critical accession rates at a catchment scale are likely to be reasonably indicative of the situation. Despite the need to minimise accessions to the watertable, it is important to allow for leaching fractions, which wash salts contained in irrigation water below the root zone. However, there are substantial opportunities for irrigators to consider leaching fractions in more detail, to accurately calculate their requirements and to manage their application.
Mapping of zones of risk can support the development of plans by management committees and guidelines about water use approvals, particularly in relation to decisions about the location and nature of future development. Hazard or risk mapping will inform the future regulation of rates of water application in specific soil types or locations, through the water use approval process and through education programs, such as
The costs associated with changing practices may be substantial. However, other benefits are derived, such as the opportunity to use water savings for other purposes, increased protection of land resources and savings in remediation costs. The opportunities to reduce accessions are more substantial in areas where the system design needs upgrading; where system design does not match soil type and characteristics; and where information that informs the decision by irrigators to irrigate could be improved.
This target is relevant to management plans under Part 3 of the Water Management Act 2000 dealing with: Division 3—Water use, Division 4—Drainage management.
Discharge of saline water from irrigation areas, industries and towns contributes significantly to the decline in water quality. However, despite recognition of the problem, data about the discharge from major drains are limited. The NSW Salinity Strategy 2000 provides the basis for this target by encouraging reductions in salt loads.
Whilst Targets 20 and 22 contribute to the reduction of the load of salt that enters watercourses, this target focuses on a specific issue that singularly contributes substantially to decline in water quality. In some instances, greater environmental effects are caused by the concentration at which salt is released.
Primarily, achievement of this target can be supported by the development of drainage management plans under the Water Management Act 2000, stormwater management plans by local government, education programs, and providing funding as an incentive. However, as a first step, monitoring to determine the severity and extent of the problem is critical.
The load and concentration of saline water can be reduced through:
• reductions in catchment salinity and reductions in remobilisation,
• improved water use efficiency to reduce accessions to the watertable,
• reuse of water in irrigation areas,
• engineering works to better manage drainage water,
• direct dilution, and
• staging the time of release, as occurs in the Hunter Salinity Trading Scheme.
The costs of monitoring may not be substantial and should be a condition on the installation and operation of major drains, whether currently licensed or not. The costs associated with engineering works or changes in catchment management to reduce loads may be more substantial. However, some significant gains can be made through minor changes in practice. The opportunities to reduce saline drainage are more substantial in the irrigated areas in the southern part of the State. The savings from activities to reduce drainage will be substantial both in terms of environmental benefit and maintenance of community infrastructure.
This target is relevant management plans under Part 3 of the Water Management Act 2000 dealing with: Division 2—Water sharing, Division 3—Water use, Division 4—Drainage management, Division 7—Environmental protection.
Water quality is one of the features of all water that is critical to the protection of aquatic ecosystem and human health and can significantly impact on the cost and productivity of many dependent industries.
Many management committees have already endorsed the NSW Interim Environmental (Water Quality) Objectives for their rivers. These objectives were developed in consultation with catchment management bodies and the broader community. They are based on environmental values and identify the water quality necessary to support the ecosystem and human related needs. In many water sources these objectives may be adequate to guide the water management needs and priorities. Where more specific guidance is needed, the current ANZECC Water Quality Guidelines and/or site specific studies may be used.
The ANZECC Water Quality Guidelines (2000) provide new and revised water quality trigger values, which, given the lack of detailed water quality and ecosystem data in many areas provides useful water quality criteria which should be incorporated into the management objectives of all management plans made under the Water Management Act 2000. The guideline trigger values are useful to indicate priorities and directions for change, while precise numerical targets only need to be as accurate as the models used to determine what catchment changes can generate the greatest improvements.
Consistent with the recommendations of the Healthy Rivers Commission for several river systems, the ANZECC Water Quality Guidelines should be used as conservative “trigger levels”. Where they are being substantially breached, this may demonstrate the need for more site-specific studies or, where the pollution sources can be identified, specific actions determined to address the source rather than to narrow the ambient water quality target.
However, wherever regulatory mechanisms, specific works or trading schemes are to be applied, more detailed site-specific studies may be appropriate to enable a better assessment of what the aquatic ecosystem is likely to be able to sustain, particularly in respect to nutrient levels.
This target is relevant to management plans under Part 3 of the Water Management Act 2000 dealing with: Division 2—Water sharing, Division 3—Water use, Division 4—Drainage management, Division 7—Environmental protection.
The NSW Salinity Strategy establishes interim salinity targets for nine inland rivers of NSW. Catchment management boards have reviewed these and made recommendations to the Government on final targets. The targets will drive a strategic, coordinated approach to managing salinity. The targets will guide investment in actions at both the landscape and property scale.
The baseline for target setting is the estimated salt load and electrical conductivity (EC) levels in the year 2000. The targets are set for 2010, as the ten year timeframe should allow adequate time for change to be achieved and measured.
The NSW Government will conduct a comprehensive review of system performance in meeting the targets in 2006 and will assess whether actions or provisions in management plans have assisted in slowing down the increase in salinity. To assess progress, the NSW Government will continuously monitor salt loads, EC levels and river flow at each target location. The Government will upgrade, and where necessary, install new monitoring equipment and will report publicly on the findings.
Catchment management boards have prepared 10 year catchment management plans, which incorporate, where appropriate catchment and management targets relating to salinity management.
This target is relevant to management plans under Part 3 of the Water Management Act 2000 dealing with: Division 2—Water sharing.
Electrical conductivity (EC) is a measure of salinity concentrations. The EC levels in a river will result from a complex function of:
• volume of flow (degree of dilution), and
• the salt load.
The relationship between flow and salt concentration is complicated and increasing the volume of flow in order to increase the dilution is generally not an effective solution unless the source of the flow is relatively low in salt. A high flow event may provide a large volume of water and theoretically a high dilution factor, however, it is likely that the higher flow is the result of a storm runoff event which may also be carrying a high salt load from the landscape to the river. High runoff events are therefore often characterised by high EC levels.
The quality of a water source is therefore a critical factor in determining the salt concentrations in downstream reaches. It will therefore be important to ensure that the flows contributed from non-saline water sources are not unduly reduced by water extractions. These sources should be identified as a matter of priority so that water extractions and transfers and dealings can be limited accordingly or salt load offsets required elsewhere to mitigate any further reductions in their contributions.
This target is relevant to management plans under Part 3 the Water Management Act 2000 dealing with: Division 2—Water sharing (Note: The mapping and assessment required will have to be undertaken as a prerequisite of planning and therefore this target may not be fully addressed in initial round of water sharing plans).
Sometimes a high quality groundwater source may be flanked by lower quality, often more saline water. Large volumes of extraction may cause the lower quality water to be drawn into the higher quality aquifer, diminishing its value and potentially making it unusable for irrigation, domestic or stock purposes.
Water quality changes resulting from water extractions should not reduce the beneficial uses (environmental values) of an aquifer. Beneficial use categories have been established in the NSW Groundwater Quality Protection Policy, and will be specified for each of the State’s aquifers.
Areas or zones where significant groundwater quality changes are a threat (water quality vulnerability zones) should be identified and measures taken to protect against this threat including:
• setting distance limits between high and low quality groundwater interface within which intensive pumping cannot occur, and
• setting groundwater quality criteria at appropriate monitoring bores which when approached, trigger a change in the extraction rate for licensed bores.
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