Australia State of the Environment Report 2001 (Theme Report)
Prepared by: Jonas Ball, Sinclair Knight Merz Pty Limited, Authors
Published by CSIRO on behalf of the Department of the Environment and Heritage, 2001
ISBN 0 643 06750 7
Water use and availability data sourced from the National Land and Water Resources Audit (NLWRA) is a major improvement on previous information, but a number of gaps remain. Most notably, estimates of water use and sustainable yield have not been made for unregulated streams in New South Wales and estimates of sustainable yield have not been made for Queensland. Most states and territories made simplifying assumptions or needed to extrapolate data when providing water use and yield estimates. In highly developed basins, with 70-100% of sustainable yield being used, approximately 75% of water use and yield estimates were based on reliable data or approximate hydrologic analysis (NLWRA 2001). However, in the overdeveloped basins, 82% of water use and yield estimates were based on poor data or were estimated without data (NLWRA 2001).
As stated previously, there is no nation-wide estimate of water use from farm dams. Projects are under way to estimate farm dam storage volumes, water use and impacts of catchment yield in a number of highly developed catchments.
The percentage of drainage regions where there was sufficient water quality data to undertake exceedance and trend assessments for six key indicators is presented in Table 44. It is likely that the coverage is slightly higher than presented below as there were other known sources of water quality data that were not made available for the assessment. Also, it must be recognised that surface water quality information for many inland arid regions may not be as important as in other areas, as these regions are largely undeveloped and do not have permanent waterways. As well, the waterways that are typical to these areas are often unique (i.e. salt lakes such as Lake Eyre) and have highly variable water quality, and there is little information on what is typical or 'good' water quality.
|Water quality variable||Waterways where there were sufficient data
to undertake an exceedance assessment (%)A
|Waterways where there were sufficient data
to undertake a trend assessment (%)B
A This equates to at least three years of monthly data collected since 1995.
B This equates to 7-10 years of monthly data collected since 1990. Flow measurements must have also been undertaken.
Overall, water quality data coverages are low. Of major concern are the low percentages for the trend assessments, and especially nitrogen and phosphorus. There were no nutrient data of sufficient quality to undertake trend assessments in Queensland waters. In Tasmania and the Northern Territory, there were insufficient data to undertake either exceedance or trend assessments for all key variables.
Other water quality indicators that have insufficient data include:
- pesticide contamination of waters and sediments
- endocrine disrupters and their impact
- other forms of nitrogen and phosphorus (e.g. nitrate and phosphate) that are important in triggering algal blooms
- the extent and impact of wastewater discharges from intensive agriculture
- algal blooms in some areas.
There are many groundwater information gaps, most of which relate to the actual physical data that are required to characterise groundwater resources. Water quality data, recharge sources, groundwater-use information and the temporal variability of the resource all require extensive investigations to obtain relevant information. The information is not easily collated, and is costly to collect. As such, much of this information is scarce, and usually available only in areas of significant development or high environmental value.
For the NLWRA, most of the groundwater use information in GMUs was collated on the basis of little or no investigation data. This is the case not only for those GMUs of low development, but also for many areas that are considered to be highly over-developed. Considering the poor reliability given to these estimates, extensive work is required to increase consistency in the groundwater-use estimates.
There is an increasing knowledge base on groundwater-dependent ecosystems in Australia; however, there still is a large gap between relating this knowledge to the management of the resource. Groundwater-dependent ecosystems are rarely included in the allocation process, and hence resources used for development could be endangering dependent flora and fauna. There is a need for assessments of groundwater-dependent ecosystems within highly and over-developed GMUs in the first instance, moving down to those GMUs of lesser development status.
Most importantly, groundwater should not be thought of as exclusive to surface water resources, but rather as one component of the hydrologic cycle.
Knowledge on the extent, distribution and condition of inland aquatic ecosystems is fundamental to their effective management and the conservation of biodiversity. There are many information gaps on the condition of inland aquatic ecosystems and these include:
- no national datasets on diatoms, the condition and distribution of native fish, frogs, waterbirds, platypus and freshwater crayfish
- no national datasets on geomorphic or physico-chemical condition, in-stream ecological processes such as community metabolism, and the condition and extent of important aquatic habitats such as riparian vegetation and wetlands
- general lack of information about aquatic ecosystems in remote rivers and the less-developed states and territories such as Tasmania and Northern Territory
- very little data on fundamental ecological processes.
Certainly, there are data for these indicators on a local or catchment level; however, these do not provide a national picture of condition. Some of these data gaps are currently being addressed through Commonwealth and state government programs.
The other major data gap is the linkage between management actions and the condition of aquatic ecosystems. Although there have been many small projects to demonstrate the effectiveness of management actions on the health of aquatic ecosystems, these results may not be able to be scaled up to larger ecosystems without further research. The impact of environmental water allocations on the health of aquatic ecosystems in large river systems is one area where additional research is required.
|Element of the environment / issue||State||Adequate information||Response||Effectiveness of response|
|Surface water use versus sustainable yields||Water use has increased by 59% since 1985 and is overused in some regions. Sustainable yields have been established in most river basins of Australia.||Water conservation.
Improvements in water use efficiency.
Setting of caps on water use.
Environmental water provisions.National Water Reform Framework initiatives.
Water conservation and efficiency have dampened the increase in demand for water.
Caps have been established in over-allocated river basins such as the Murray-Darling and coastal NSW. Queensland the exception.Environmental water provisions are being developed, but very slowly.
Still relatively little implementation of environmental water provisions.
|Groundwater use versus sustainable yields||Groundwater use has increased by 88% since 1985 and is overused in some areas. Sustainable yields have been estimated for most groundwater management units, but have been estimated using different methods and different definitions in each state. Seawater intrusion occurring in many coastal aquifers, which is caused by groundwater pumping.||Groundwater bores require metering in many areas to understand groundwater use better. This should be incorporated within groundwater management plans for each GMU.
Sustainable yield estimates require updating with new information as acquired.
|Increased effort has been directed at groundwater management and the management of groundwater information.
There is no consistency in groundwater information across Australia and no base level of groundwater information collated.
|Climatic shifts||Evidence of a decrease in inflow to Perth water supply reservoirs.||Adjust sustainable yields.
Adaptive water resources management.
Research into causes for the change in yield.
Adjustments to security of supply modelling have been made.
Causes for the long-term change in inflow are not well understood.
|Forest management||Catchment yield is affected by logging and forest regrowth.||Various catchment specific studies.
Incorporation of water issues in forestry planning.
Hydrologic studies are now considered part of forestry planning.
|Farm dams||Proliferation of dams has reduced streamflow, particularly during dry conditions.||Embargoes on the issue of new licences and farm dam construction.
Catchment specific studies.
Changes to licensing arrangements so that licences are required for large farm dams.
|Appropriate.New farm dam construction has been stopped in areas with high water use.Legislative changes being developed and consulted upon.Research to speed up assessments for new farm dams is continuing.|
|Farm forestry and tree clearing||Still a net clearing of vegetation nation-wide.
Net tree planting occurs locally.
|None.||Poor. The hydrologic effects of tree clearing and replanting are not considered in catchment planning. Information on these hydrologic effects is not in a readily applicable form.|
|Irrigation||Water extracted for irrigation has increased by 73% since 1985.||Improved irrigation practices.
Retirement of land agriculture enterprises not suited to irrigation.
|Poor. There have been improvements in irrigation practices in some areas. Greater investment is required.
No review of sustainability of irrigation for specific agricultural uses and areas.
|Groundwater and surface water interaction||Concern that increases in groundwater use might reduce surface water flows.
Increased groundwater use also means that ecosystems dependent on groundwater may be impacted on.
Licensing and monitoring of groundwater use.
Embargoes on the issue of further groundwater licences in overused aquifers.
Inclusion of GDEs in the sustainable yield estimates (including river baseflow).
Determination of groundwater-dependent ecosystems and their environmental water requirements for each GMU.
Interactions between surface water and groundwater have not yet been well quantified.
More investigations are required into environmental water provisions for GDEs, including impacts on river baseflow.
|Catchment pollutant sources|
|Agriculture and land clearing||As for the 1996 SoE Report, most waterbodies in areas of agriculture affected by fine and coarse sediment, elevated nutrient loads, and, in some cases, salt; increased volume and rate of run-off; major stream channel changes.
Land clearing for agriculture continues with greater than 400 000 ha annually cleared in Queensland since 1995.
|Strategic revegetation and farm forestry; clearing bans; drainage; broadacre soil conservation and fertiliser management; tree planting to reduce salinity; streambank stabilisation; catchment management and Landcare.||Poor - some improvement since 1996 with greater awareness of issues and increased implementation of erosion control measure. Broad scale land clearing has largely ceased except in Queensland and to a lesser extent New South Wales.
Tree planting only contributed to less than 2% of vegetation regrowth.
Riparian vegetation restoration and re-snagging rivers becoming more widespread.
|Mining||As for the 1996 SoE Report, localised pollution by metals and acid run-off; many sites of disturbance in past areas of coal, alluvial tin and gold mining, sulfide mining and sand and gravel extraction.||Stricter management of all new mines; recycling of water; stabilisation and rehabilitation of some old mine sites.||Good in relation to new mines; poor in relation to old mines.
Programs to rehabilitate old mines sites are active in most States.
|Intensive animal industries||No additional information from the 1996 SoE Report; however, number of facilities has increased.||Guidelines and regulations for effluent discharges, operation, and management; education; implementation of regulations.||Still little information known on the contribution and impacts of pollutants.
Regulatory control of industry poor.
|Irrigated industries||As for the 1996 SoE Report, localised but significant pollution by sediments, nutrients, pesticides, salt and waterlogging producing serious environmental and social problems.||Guidelines and regulations for effluent discharge and drainage in some areas; improved irrigation techniques; soil conservation; education; industry restructuring; water industry reform.||Poor but improving.
Some improvements in irrigation and agricultural practices.
Effluent and drainage disposal still largely unregulated.
New water quality guidelines provide additional information on biological effects.
Structured land and water management more widespread, however, does not consider sustainability.
Water reforms and restructuring generally being implemented but very slowly.
|Urban and industrial development||As for the 1996 SoE Report, localised but significant pollution by sediment, nutrients, oils, organic chemicals and metals.||Guidelines and regulations for effluent management; monitoring; education; increased reuse of wastewater; improved treatment of effluent; improved stormwater management.||Good for trade wastes and industrial discharges. NPI will provide additional information.
Poor but improving for urban run-off with the preparation of stormwater management plans, improved treatment and community education.
Increased wastewater reuse.
Monitoring inadequate for groundwater.
|Forestry||As for the 1996 SoE Report, localised pollution by sediments, nutrients and pesticides.||Guidelines and field practice manuals; buffer strips; patch and selective logging; strategic forest and plantation planning.||Improvements in logging practices in many areas. Movement to plantation forestry rather than native forest logging.|
|Habitat quality and biota|
|Habitat and physical pressures||Communities within rivers and streams are significantly impacted by river regulation and instream barriers.||Significant programs of fishway development and implementation of environmental flow regimes.||Some fishways are ineffective.
Too early to determine benefits of flow modification improvements.
|Biological pressures||Presence of exotic species appears to be having a detrimental effect on aquatic ecosystems.||Programs of exotic pest control and research into impacts.||Appears some species have had specific benefits, although no determination of long-term success as yet.|
|Riparian vegetation condition||Weeds now dominate much of the riparian zone of rivers, and clearing also has a significant impact.||Programs of revegetation, stock control, investigation into techniques and causal mechanisms.||Revegetation and stock management appear to be having significant benefits in current limited trial plots.|
|Wetland extent||Wetland area continues to decline significantly||Wetland protection mechanisms through policy such as RAMSAR listing.||Limited effectiveness because RAMSAR cannot be enforced to improve management.|
|Waterbird populations||A significant proportion of waterbird species are under conservation threat.||International agreements such as JAMBA and CAMBA.Series of action plans at a national level for threatened species.||Unable to currently determine if there have been any benefits from these programs.|
|Stream health||AusRivAS assessment indicates that stream health is strongly linked with the degree of development of catchment and waterway.||Combination of all the responses will improve stream health.||Not applicable.|
|Fish communities||There have been significant reductions in range and abundance of some native fish species.||Widespread fish restocking programs across states.||Little data on overall changes in population abundance due to actions.|
|Frog population conditions||A decline in frog species abundance appears to be occurring in south-eastern Australia.||Limited collation of data to determine if there is a decline.||For some species specific actions have been effective (e.g. Green and Gold bell frog).|
|Salinity||High salinity in south-west Western Australia and western Victorian rivers. Significant increases in salinity predicted in many catchments over the next 50-100 years.Dryland salinity is the major contributor to increases in river salinity.Increasing groundwater salinity in some water table aquifers.||National and state salinity strategies.Integrated catchment strategies involving tree planting; education; maximising plant water use; improved irrigation practices; salt diversion schemes. Improved groundwater management through groundwater management plans for each groundwater management unit.||Unknown as yet as many strategies have only been released.
Salt diversion schemes in Murray-Darling successful but only a stop-gap measure.Sustainability of agriculture does not appear to be addressed.Questions on whether adequate funding is provided.
|Eutrophication and algal blooms||High nutrient levels in many rivers.Blue-green algal blooms are widespread throughout Australia with some reservoirs having persistent blooms.Subsoil erosion is the major source of nutrients in most catchments.||National and state eutrophication strategies.Integrated catchment strategies involving revegetation; education; improved irrigation practices; erosion control.Riparian vegetation restoration.Understanding of algal bloom development.||Land and water management plans prepared for many catchments, however, implementation has been slow.
Erosion control is poor in rural areas. Agricultural practices are poor.Improvements in the management of nutrients in urban areas.Riparian vegetation is being restored in some areas, but overall still remains highly degraded.Improved understanding of the causes and development of algal blooms.
|Pollutants||Localised pollution from mining, agriculture, industry and urban development.Potentially widespread contamination from pesticide use in agriculture.||See respective sections for status.Regulatory control; application practices; use of new less toxic and more selective pesticides.||Difficult to assess as pesticide monitoring is not widespread.Improved use and control of pesticides in some areas has shown a decrease in river concentrations.|
|Groundwater pollution||Pollution from industries and agricultural use of land.||National groundwater quality guidelines are operational, but are not enforced as well as required. Lack of information on groundwater quality in many regions.||Needs more enforcement by environmental agencies and more groundwater monitoring to determine the breadth of the problem.|
|Acidification||Increasing acidity in some rivers measured.Area of land with acid soils increasing considerably.||Restoration of 'natural' environments. Liming and other soil management practices.||Poor - liming is not common in Australia.|