The quality of water in our rivers and aquifers is dynamic and varies with time and location. Water quality can be affected by natural processes and by human practices. Natural factors include the local geology which influences salt and nutrient inputs as well as climate, riparian vegetation and stream flow. There are a wide range of human practices that may change water quality. This includes sewage discharge, mine waste, land clearing and urban and agricultural development.
The regulation of stream flow by dams and weirs impacts water quality. The extraction of water also influences the quality of water. Many rivers receive less floods and flow events. These would naturally clean and flush the river. Degraded water quality can be a short term problem for rivers. Groundwater can be thousands of years old. So contamination of groundwater has long-lasting impacts.
The National Water Quality Management Strategy provides guidance on managing water quality. The strategy establishes guideline values for various water quality measures. Following consultation with the community, interim water quality objectives are in place in NSW. They help decision makers consider water quality in both big picture strategic planning and at the local level in assessing impacts of development.
Water licences authorise the management of contaminated irrigation or mining water, sewage discharge and other point source pollution.
The department has developed water quality management plans for each water resource plan area in NSW.
Waterwatch NSW is a community-based program in water quality monitoring. The program involves landholders, community groups and schools in water quality monitoring. It engages communities in protecting the health of local waterways. This information helps to inform government and natural resource managers on the health of our local waterways.
A new database launched in 2010, and other resources, help Waterwatch groups do their work. Manuals, guides and posters help with water quality sampling methods and techniques. The database allows groups to enter water quality monitoring results.
For further details please visit Waterwatch