Finding pollution sources

Finding pollution sources

officer testing water quality

We use the Pollution Source Assessment Tool to identify pollutant sources in the catchment.

There are many potential pollutants in the catchments which need to be managed and monitored to stop them contaminating water supplies including:

  • Sediment run off which can be carried into the water by rainfall, particularly after droughts and bushfires. It can increase turbidity (cloudiness) of water and carry other pollutants with it.
  • Pesticides and chemicals from industry and farming which can pollute the water.
  • Nutrients such as phosphorous and nitrogen, from fertilisers and detergents, washed into the storages which can encourage algae to grow.
  • Algae which can change the taste and smell of water and clog up water treatment plants. Some blue-green algae (known as Cyanobacteria) can produce toxins that can make people or animals sick.
  • Pathogens which are disease causing micro-organisms like Cryptosporidium and Giardia found in human faeces, animal and bird droppings.

How we track and mitigate these pollutants

We have developed a sophisticated Pollution Source Assessment Tool which is a geographic information system that brings together data on the sources, causes and pathways for pollutants.

WaterNSW uses the tool to understand where the high risk pollution sources are in the catchment. This allows us to better target our catchment actions to protect water quality.

For example, this tool has identified that the five most significant pollutant sources in the catchment are:

  1. grazing
  2. intensive animal production
  3. on-site wastewater management systems
  4. sewage collection systems
  5. urban stormwater.

See more information about the Pollution Source Assessment Tool.

We use this information to inform and guide our catchment management activities and interventions to improve the quality of water across the catchment.


Wednesday 10 August
2,587,276 ML
2,618,706 ML
7,978 ML
1,140 ML
-8,295 ML
Wednesday 10 August