Water resources past and present

Geological evidence from a number of localities indicates the presence of large bodies of water in inland Australia in the past. Conservation of water can involves re-use of water and optimisation of the efficiency of water usage. In Australia, water systems can be affected by pollution, salt water intrusion and ground salinity. There are state and federal government policies related to the use of ground water and possible scientific solutions to environmental problems associated with the use of ground water.

Groundwater use and management in NSW

Groundwater is a relatively poorly understood resource subject to long time lags. Though it may take millions of years to accumulate, groundwater is the single largest source of water in the state sustaining agriculture, industry and many inland communities.

Conjunctive use of ground and surface waters

Conjunctive use is the combined use of surface water and groundwater storage to optimise total available water resources. Irrigators who are located near surface water supply channels or rivers may opt to pump either surface or groundwater depending on irrigation demand. In the Coleambally Irrigation area for example, one irrigator pumps groundwater year round into a supply channel and is then able to extract an equivalent volume to irrigate rice when required. This strategy saves infrastructure costs associated with storing large volumes of groundwater in dams. 

In many cases, the close hydraulic connection between surface and groundwater means that both resources would be best managed by a single extraction policy. In fact pumping groundwater from sediments near a river merely filters river water!

Groundwater Management Policy in NSW

History of policy development

Limited supplies of water and declining water quality has made the need for reformed water management increasingly urgent. The Water Reforms, were introduced in NSW in 1995 in response to the Council of Australian Governments decision in 1994 to improve water management. Groundwater management in NSW included in the Water Reform process is implemented by the Department of Land and Water Conservation in accordance with the goal to manage the State's groundwater resources so that they can sustain environmental, social and economic uses for the people of NSW. 

It has been recognised that the precautionary principle of ecologically sustainable development (ESD) is particularly relevant to a relatively poorly understood resource subject to long time lags.

Principles

1. An ethos for the sustainable management of groundwater resources should be encouraged in all agencies, communitites and individuals who own, manage or use these resources, and its practical application facilitated. In order to encourage a stewardship ethic for groundwater management, the importance of raising community awareness, via education programs and inclusion the in the development of local Groundwater Management Plans. 

2. Non-sustainable resouce uses should be phased out. Some activities which are not compatible with groundwater resources, such as disposal of insufficiently treated sewage into permeable coastal sand aquifers, need to be phased out or modified. 

3. Significant environmental and/or social values dependent on groundwater should be accorded special protection. This includes wetlands and other groundwater dependant ecosystems which support threatened species, or where town water supplies draw from groundwater. 

4. Environmentally degrading processes and practices should be replaced with more efficient and ecologically sustainable alternatives. 

5. Where possible, environmentally degraded areas should be rehabilitated and their ecosystem support functions restored. 

6. Where appropriate, the management of surface and groundwater resources should be integrated. 

7. Groundwater management should be adaptive, to account for both increasing understanding of resource dynamics and changing community attitudes and needs. 

8. Groundwater management should be integrated with the wider environmental and resource management framework, and also with other policies dealing with human activites and land use, such as urban development, agriculture, industry, mining, energy, transport and tourism.

Components of State Groundwater Policy

There are three parts to State Groundwater Policy: 
1. Quality Protection Policy 
2. Quantity Management Policy 
3. Dependant Ecosystems Policy 

The Quality Protection Policy was released in 1988, while the other parts are currently in development.

Quality Protection Policy

The objectives of this policy are to slow and halt, or reverse any degradation in groundwater resources, and to direct potentially polluting activites to areas where risk to groundwater is minimised. Part of implementing this policy involves establishing a review processs for developments, and developing groundwater vulnerability maps and groundwater protection zones where needed. The principles of this policy may be summarised: 

1. All groundwater systems should be managed to maintain the most sensitive beneficial use. 

2. Special protection for town water supplies. 

3. Groundwater pollution should be prevented so that future remediation is not required. 

4. Efforts to project groundwater for new developments, should reflect the risk and value of the resource. 

5. Groundwater pumpers are responsible for environmental degradation caused. 

6. Protection of groundwater dependent ecosystems. 

7. Integration of quality protection and quantity management. 

8. Recognition of cumulative impacts on groundwater quality. 

9. Environmentally degraded areas should be rehabilitated if possible.