Rivers and Wetlands – Quick Facts

Water Use

• Australia uses about 24,000 gigalitres (48 Sydney Harbours worth) of water each year and most comes from our rivers.

• About 74% of all water is used for irrigation, for crops like cotton, rice and citrus.

• Around 70% of Australia's total water use occurs in the Murray Darling Basin. No other system in Australia comes close to this level of use.

• Contrary to the belief that this level of use is 'historical', much of the development of water resources has happened relatively recently. This means much of the ecological impact is still to be felt.

• Between 1983-1997 there was a 65% increase in water use across Australia, mostly from our rivers. This included a 52% increase in NSW - most of this growth was for irrigation.

• Water is stored in public dams and weirs, but also in private storages which capture big flows when they are running over the floodplains, or pumped from rivers at times of high flows.

• On the Gwydir, almost an entire Sydney Harbour's worth of off-river private water storage has been built over a twenty year period (1975-1995) which compounds the impact of Government built storages.

Impacts on River Health

• Scientific opinion is that healthy working rivers require at least two thirds of their natural flow. Currently annuals flows at the end of the Murray, Murrumbidgee and other major rivers are between one third and half their natural levels as a result of irrigation.

• The percentage of native fish as a proportion of total fish populations in the Murray, Tumut and Murrumbidgee rivers has been reduced to twenty percent, with introduced species such as carp making up the rest. Some estimates suggest that the native fish population has been reduced to 25% of pre-settlement numbers (Silver Perch are only 5% of 1960s levels).

• Blue-green algal blooms have always occurred on our rivers. They are a natural part of the system but their incidences have increased, particularly in the Murray Darling basin, because there is less water in the river systems.

• Salinity is expected to increase in rivers as a result of dryland salinity. Reduced flows in rivers exacerbates this problem..

Impacts on Wetlands

• Research indicates that once you get west of the divide, biodiversity is clustered in 'hotspots' - centred on wetlands and floodplains which fill up when our rivers flood.

• Dams and extractions to on-farm storages alter the natural flow of the river, impacting on how often these wetlands and floodplains are flooded

• The Lowbidgee (a large wetland at the end of the Murrumbidgee) covered more than 300,000 hectares at the turn of the century. Today three quarters of this area has been destroyed because of reduced flows from upstream, and development of the floodplain.

• Correspondingly, there has been a decline of more than 80% over the last twenty years in the numbers of waterbirds found on the Lowbidgee floodplain and this includes waterbirds that feed on fish, frogs, plants and insects. It is likely that these organisms have had similar declines.

• Red gum and eucalyptus along rivers are reduced in area and health.

• Graziers who rely on floodplains for stockfeed are also significantly impacted by upstream irrigation

Current Political Developments: irrigators to "own" the water in our rivers.

At present in NSW, water users are guaranteed a certain share of the river water for ten years through a "water sharing plan" (WSP). The first plans commenced in 2004.

Every ten years the plan is reviewed, and the volume of water available for consumption for drinking or agriculture is recalculated. No compensation would be available to water users for reductions at this point. The present plans entrench ten years of high levels of water use (see above), but were considered a "first step" in the long term plan to restore rivers to health.

The Commonwealth and States are now negotiating a National Water Agreement. In June 2004 COAG issued a communiqué outlining the principles for the NWI, including the following arrangements for compensating water users whose access to water is restricted:

• reductions arising from natural events such as climate change, drought or bushfire to be borne by water users,

• reductions arising from bona fide improvements in knowledge about water systems' capacity to sustain particular extraction levels to be borne by water users up to 2014. After 2014, water users to bear this risk for the first three per cent reduction in water allocation, State/Territory and the Australian Government would share (one-third and two-third shares respectively) the risk of reductions of between three per cent and six per cent; State/Territory and the Australian Government would share equally the risk of reductions above six per cent,

• reductions arising from changes in government policy not previously provided for would be borne by governments, and

• where there is voluntary agreement between relevant State or Territory Governments and key stakeholders, a different risk assignment model to the above may be implemented;

If implemented in NSW, this agreement will mean that present practices will continue until 2014, when present water sharing plans expire.

After 2014 the Government could ask water users to reduce their use by just 3% without compensation, and any additional reduction would require compensation at full market price. The present market price for water is around $1000 a megalitre. Many millions of dollars would be required to return river flows to healthy levels under these arrangements.

More Information

Inland Rivers Network www.irnnsw.org.au
Nature Conservation Council www.nccnsw.org.au
Murray Darling Basin Commission www.mdbc.gov.au; www.thelivingmurray.mdbc.gov.au
The Macquarie Marshes Management Committee www.macquariemarshes.com
Wetland Care Australia www.wetlandcare.com.au