• Extent of Dryland Salinity in Australia
• Impact of Dryland Salinity in Australia
• Addressing the Challenge
• NDSP Goal
• Action Statement

Extent of Dryland Salinity in Australia

Dryland salinity is a major threat in many parts of Australia. It is presently estimated that about 2.5 million ha of land is affected and that there is a potential for this to increase to 12 million ha. This area represents approximately 4.5% of presently cultivated land and is costing in the vicinity of $130 million annually in lost agricultural production, $100 million annually in damage to infrastructure, and at least $40 million in loss of environmental assets.

Area of land reported to be affected by salinity in Australia
(Figures are best approximations due to limitations in some data)

In Western Australia the existing 1.8 million ha of salt-affected farmland could easily double in the next 20 years or so, and then double again before an equilibrium state is reached. Of the State's divertible water resources, 36 percent is brackish or saline and a further 16 percent is of marginal quality.

All principal agricultural districts in South Australia exhibit some degree of dryland salinity and at least 20 percent of the surface water resources are more saline than the recommended limits for human consumption.

The present estimates of dryland salinity in Victoria may well increase substantially as more detailed mapping is continued. In New South Wales as much as 5 million ha could be affected in the future as groundwaters rise in areas underlain by Ordovician meta-sediments with yellow and red texture contrast soils.

The Queensland estimate of 10,000 ha of salt affected land refers to severe salting. Dryland salinity is an emerging issue in both Queensland and Tasmania.

Impact of Dryland Salinity in Australia

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Agricultural costs

Agricultural costs are frequently expressed in terms of the value of lost production, estimated to be at least $130 million annually, but a more fundamental concern is the cost of protecting land and surface waters from salinisation, something which has not been well valued. Many industries are impacted by dryland salinity, particularly the grains and grazing industries. In many instances, salinity may threaten entire farm enterprises. The nature of salinisation, however, means that industries must take whole of property and regional approaches to solutions.

In some cases, salinisation has reached thresholds where the only practical management of affected lands is to use them productively as a saline resource. In these cases, opportunities are presented for new industries that can profitably use saline resources while preventing further downstream degradation.

Stream salinity

Throughout the Murray-Darling Basin there is a rising trend of salt concentrations in many streams - particularly in the southern half of the Drainage Division.

Presently the Murray Drainage Basin exports 3 times the amount of salt that is input from the atmosphere whilst the Darling Basin is closer to a 1:1 ratio. The large imbalance between input and output of salt in the Basin is a direct reflection of increasing groundwater pressures in that area and the consequent increase in groundwater discharge to the soil surface and into streams. This situation has tremendous consequences for the water supply for downstream townships and cities.

Offsite effects

Very few sectors of Australian society are not affected by salinity at least indirectly. Offsite effects of salinity are usually encountered through water quality. Industries that may be affected include:

• Water and waste water (water supply and treatment)
• Information and education (dissemination of salinity information)
• Energy (coal mining, electricity generation)
• Communications (telephone cables)
• Supply infrastructure (gas pipelines)
• Science and technology (salinity research)
• Production economics (farm costs)
• Finances (banks)
• Infrastructure (Local Government)
• Housing (urban salinity)
• Transport (roads)
• Tourism (National Parks)
• Trade (marketing organisations)
• Government planning (regional and economic development)
• Heavy Industry (steel, aluminium, paper)
• Cultural (including Aboriginal)

Local government, public utilities and government agencies

Councils and public works departments may find it difficult to separate out the proportion of their repair costs due to salinity as compared with 'normal' maintenance costs, but it is acknowledged that road and bridge damage caused by salinity is a major concern.

In the south-western region of NSW alone, road damage due to high water tables is costing about $9 million per year. It is thought that approximately 34 per cent of state roads and 21 per cent of national highways are affected in this way.

The nature and extent of costs that salinity poses to local governments and public utilities across many parts of Australia are exemplified by the situation in Wagga Wagga, NSW:

Annual Recurring Costs of Salinity in Wagga Wagga

Declining incomes within regions affected by salinity also have significant social and economic consequences, which strain the services available to the rural population. A reduced ratings base can exacerbate problems faced, or being addressed, by shire councils.

Urban household costs

There are a considerable number of areas where saline water and high water tables could impact on urban households, for example:

• damage to septic tanks
• damage to hot water systems and other household applicances
• increased use of soaps, detergents and water softeners
• reduced life of clothing
• damage to vehicle radiators
• damage to buildings
• damage to water and gas supply pipes and fittings
• damage to gardens, lawns, pot plants etc.

Environmental costs

Salinity poses a major threat to many environmental assets, including:

remnant vegetation

• fauna and flora diversity
• riparian vegetation
• wetlands
• fish, birds and animal habitats

Many of the costs associated with the environment are difficult to quantify, although novel benefit cost analyses undertaken in South

Australia cost the loss of one particular wetland at $20 million.

Addressing the Challenge

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The NDSP was established in 1993 because a national problem, as presented by dryland salinity in Australia, demanded a national approach. Research and development (R&D) in the first phase has greatly expanded understanding of the processes of dryland salinity and of their management. Some of the key messages derived from outcomes of the first phase are presented on the inside back cover of this plan.

The second phase of the NDSP intends to build on the work undertaken in Phase I to address knowledge gaps in the use and rehabilitation of salinised land and water resources. The second phase also intends to facilitate action to prevent and manage dryland salinity. In planning for the second phase, it has been recognised that:

• there is great urgency in the need to address the impacts of dryland salinity on biodiversity, agricultural production, public and private infrastructure, and regional and rural communities;
• investors in on-ground works that manage dryland salinity need further R,D&E to improve the effectiveness of their work;
• communication and extension activities should facilitate transfer of lessons learnt from the focus catchments involved in phase one;
• the present operating environment does not adequately encourage adoption of best practice management for dryland salinity;
• some parts of the landscape are irreversibly affected by salinity, so new uses and management practices must be developed for these salinised resources; and
• there are still significant knowledge gaps in the complex interrelationship between managed ecosystems, rural landscapes and hydrogeological systems.

To address this challenge, a clear goal and commitment of the NSDP in its second phase is required:

NDSP Goal

The National Dryland Salinity Program will research, develop and extend practical approaches to effectively manage dryland salinity across Australia.

Action Statement

The NDSP is committed to the strategic investment of funds into dryland salinity research, development and extension (R,D&E) that will improve the management of landscapes by focussing on:

• causes, costs and solutions
• institutional arrangements
• management of saline landscapes
• landscape ecosystems and processes

and by ensuring that:

• there is a framework for stakeholders to invest collaboratively and efficiently in addressing dryland salinity
• the program takes a national leadership role that will ensure the investments address priority areas and issues
• investment targets the development of tools that facilitate the adoption of solutions via catchment-scale planning processes
• a clear communication and extension pathway exists for products and services arising from program activities
• linkages with other relevant initiatives and programs are facilitated.

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