Numerical modelling

Numerical/mathematical/computer models use one or more mathematical equations to simulate the behaviour of real systems under a wide range of conditions.

Why use a model?

Models have a wide range of applications and benefits, some of which are outlined below.

Numerical models can be used to make predictions about the outcomes of a particular mangement scenario, for example, determining potential impacts of different types of landuse on a range of environmental aspects, such as water quality, for a set period of time;
They can also be used in hindsight, to assess the effectiveness of management actions and to evaluate the influence of natural factors on the environment, such as climate change;
Numerical models can be used to assist setting water quality objectives as well as assessing their effectiveness. The publication Targets, Data and Models: Catchword. Issue 127. May 2004 has more information about using models for setting and assessing water quality objectives (Note: WQOs are referred to as 'targets' in this document);
Modelling helps users to develop an understanding of physical and biological processes in their waterways; and
Models can assist users in developing management plans for their waterway.

Choosing a model

Click on an water quality issue to find existing modelling tools available for that water quality issue.

Freshwater flow regime	Hydrodynamics	Suspended sediments
Nutrients	Organic matter	Toxicants
Bacteria/pathogens	pH	Water temperature
Litter	Excess salt (hypersalinity)	Excess freshwater (hyposalinity)
Habitat removal/disturbance	Biota removal/disturbance	Pests