Freshwater

An aquatic ecosystem is a waterbody where plants, animals, the water and climate all interact in a delicate balance.

Natural freshwater ecosystems

Examples include:

• Rivers

  • Hunter River⁹

  • Murray – Darling River¹⁰

  • Hawkesbury River¹¹,

  • Murrah River¹²

  • Wakool River¹³

• Creeks – for example, Rocky Creek¹⁴

• Wetlands

  • Kooragang Wetland¹⁵

  • Hunter Estuary Wetlands¹⁶

  • Ramsar Wetlands¹⁷

  • Lachlan Wetlands¹⁸

  • Gwydir Wetlands¹⁹

  • Macquarie Marshes²⁰

• Freshwater Lake – for example, Blue Lake²¹

• Underground (Aquifers) – Groundwater Dependent Ecosystems²²

Man-made freshwater ecosystems

Examples include:

• Stormwater quality improvement devices²³ (SQIDS) – retention/detention basins

• Drinking Water Storage Dams – for example, Grahamstown Dam²⁴

• Farm dams²⁵

Animals that live in freshwater waterways rely on their habitat (the water environment) being healthy and clean to survive and maintain their populations.

Examples of animals that live in freshwater

Animals that live around freshwater waterways rely on the riparian area (the vegetation and land bordering the waterway) being productive, healthy and well balanced for their survival.

Examples of animals that live around freshwater

Types of plants

• Aquatic plants⁴⁰ (plants that live in water)

• Riparian/terrestrial plants⁴¹ (plants that live on land around waterways).

Role of plants

Plants play an important role in helping to keep waterways healthy by:

• providing instream habitat (homes) and food for animals

• stabilising banks (holding together the bank with the root system) to prevent soil from being transported away from the site through the process of erosion

• protecting waterways from sunlight (maintain temperature)

• providing terrestrial (out of water) habitat for animals.

The cause of water pollution can vary dependent on the locality, either urban (in towns or cities, large population in small area) or rural (less populated areas, no curb and gutter on roads) environments.

Urban areas

Possible causes of polluted stormwater⁴² include:

• car washing

• chemicals poured down drains (intentionally or otherwise)

• litter

• dog faeces

• grass clippings

• paint

• oil

• garden fertiliser

• sewage

• dirt/soil and other loose sediment.

The Office of Environment and Heritage suggest a range of strategies to reduce stormwater pollution⁴³.

Rural areas

Rural water pollution can come from single point and diffuse sources⁴⁴ such as:

• urine and faeces from livestock

• pesticides

• herbicides

• farm grade fertiliser

• livestock access (eroding the banks and stirring up the mud-turbidity)

• increased salt from salinity and industries that turn up the ground

• sewerage from septic tank leaks

• dirt/soil and other loose sediment.

Water NSW has a leadership role in minimising water pollution in all catchment areas⁴⁵.

To maintain waterway health we need healthy catchments. Everything we do in catchments affects the fragile water ecosystems.

Your role

Actions we can take every day to keep our catchments healthy include:

• keeping livestock out of rivers and creeks

• using fertiliser responsibly

• making sure rain is the only thing to go down the drain

• washing our cars on the lawn and

• planting trees around waterways to increase their structural strength and provide habitat for wildlife.

Contact information

• Contact your local Waterwatch Coordinator⁴⁶ to find out how you can be involved in positive environmental action in your school or community.

• Contact your regional Catchment Management Authority⁴⁷ to find out how to improve your land management practices on your farm.

Freshwater Environmental Education Centres

NSW DEC Environmental Education Centres providing access to freshwater ecosystems include:

• Rumbalara⁴⁸ (Hunter/Central Coast)

• Cascade⁴⁹ (North Coast)

• Thalgarrah⁵⁰ (New England)

• Field of Mars⁵¹ (Northern Sydney)

• Georges River⁵² (South Western Sydney)

• Illawarra⁵³ (South Coast)

• Longneck Lagoon⁵⁴

• Royal National Park⁵⁵

• Red Hill⁵⁶.