Aquatic health

Aquatic health is one of three conceptual models that broadly focus on the biophysical systems in our region. They describe the ‘health’ of the systems and should be considered in association with the socially based conceptual models and subregional information to get a full picture of what we know about our region.

View the aquatic health model.

About aquatic health

The inland waters of the AMLR region include surface water (rivers and streams) and wetlands. The major catchments include the Light and Gawler rivers (including North and South Para) in the north, the Torrens and Onkaparinga rivers, and a number of smaller catchments on the Fleurieu peninsula, the largest being the Hindmarsh and Inman rivers.

There are a wide range of benefits from healthy aquatic systems; they can broadly be thought of in two groups:

  • Benefits from using the water (consumptive) occur when water is taken from a system and used for productive purposes. This often generates private benefits. The wide range of water users in the region include agriculture (irrigation and stock watering), industry and public water supply.
  • Benefits of healthy waterways (non-consumptive) occur without extracting water from the system. They can include protection from floods, reduction of pest species, links to cultural heritage and opportunities for recreation and tourism. Non-consumptive benefits are often of a public nature and contribute to social wellbeing.

Many factors can influence the health of an aquatic system, including the water flow and regime (volume and timing of water available to ecosystems). The water flow, or regime, is influenced by surface and groundwater. Water quality is influenced by runoff and activities in the catchment.

The extraction and use of surface water (rivers and streams) can clearly impact on the health of an aquatic ecosystem; the use of groundwater can also impact on aquatic health in surface water because of interactions between surface and groundwater resources.

A case study: Using environmental flows to increase the Onkaparinga River’s resilience

The Mount Bold reservoir is part of the Onkaparinga River aquatic system and is an important source of water for human consumption. However, the reduced flow as a result of dams introduced to the system in the Onkaparinga River, had significant environmental impacts including on the health of the estuary.

Providing environmental flows in the river and monitoring the response of the system to those flows has shown the condition of the aquatic ecosystem improve from fair to good.

This case study is a good example of how the environmental, economic and social needs of a system need to be balanced to achieve the desired outcome.

Related links

Natural Resources Adelaide and Mount Lofty Ranges