Balancing Consumptive and Environmental Water Use –An Australian Perspective - Water and Agriculture: Sustainability, Markets and Policies - page 177

and pastures that have shallower roots and different water use requirements, substantial
rises occur in water tables due to increased recharge of groundwater. This often results in
increased salt loads entering the river systems. Reduced river flows, brought about by the
construction of dams, weirs and water diversions, compound the problem as the flow is
insufficient to dilute saline groundwater inflows.
Salinity through irrigation resembles dryland salinity, with the exception that
groundwater accession is induced through irrigation water rather than rainfall recharge.
Irrigation salinity arises when the volume of irrigated water exceeds evaporation and the
transpiration of agricultural plants. Contributing factors include inefficient watering
systems and inadequate drainage infrastructure.

Increased nutrient loading and sediment accumulation
Agricultural practices have accelerated the leakage of nutrients and sediments from
Australian landscapes (ABS, 2003). Total phosphorus loads in rivers average 2.8 times
higher than estimates for pre-European settlement levels and total nitrogen loads are
2.1 times higher (NLWRA, 2001). The leakage of nutrients stems predominantly from
erosion and dissolved phosphorus run-offs. Excessive nutrient levels in river systems
results in eutrophication and can lead to increases in the occurrence of algal blooms.
The accumulation of sediments stresses many Australian river systems. River system
stress from sediment runoffs from catchments is exacerbated by artificially-altered flow
regimes. About 30,000 kilometres of river length have experienced sediment
accumulation of greater than 0.3 metres since European settlement. The Murray-Darling
Basin is one of the worst affected basins, with 20 per cent of river length accumulating
more than 0.3 metres of sediment (ABS, 2003).

4. Balancing consumptive and environmental water use — The environmental

aspects of Australian water reform

Balancing consumptive and environmental water use, striking a compromise between
providing the flows required to maintain and restore healthy rivers with water allocation
for consumptive users, is an important dilemma facing Australian governments and
communities. In response to these pressures, Australian governments have adopted an
intergovernmental and multi-stakeholder approach that emphasises co-operation,
consultation and dialogue between the stakeholders.
Australia's system of government is three-tiered: commonwealth (“Australian
Government”), state/territory, and local. There are six state and two territory
governments, and over 730 local governments. In Australia, a multi-stakeholder approach
is often adopted to maximise the viability of and support for environmental remediation
activities. This process necessitates co-operation and active participation from
stakeholders. The programmes and initiatives discussed in this section are negotiated
outcomes between different levels of government and representatives from industry and
community groups. Typically, national and interstate plans involve the Australian
Government and the relevant state and territory governments, while intrastate and
regional programmes involve a state/territory government and its local governments. This
section highlights national land and water reforms taking place across Australia.