How do you develop draft water quality objectives?

Draft water quality objectives are derived directly from the guideline values. Water quality objectives (WQOs) are measurable yardsticks that need to be achieved to maintain or restore the community’s initial choice for environmental values (EVs) of waterways in the study area and the water quality guidelines to protect them. The specific water quality objectives more tightly define the desired level of water quality, and are compared with the existing water quality to assess performance.

Since some water quality indicators are used for more than one EV (e.g. salinity or some toxicants can refer to both primary industry uses and to ecosystem protection), it is possible to have two different guideline values for one indicator. In this situation, the most stringent guideline for each water quality indicator is the draft WQO selected (i.e. it will protect all identified EVs).

These form an intitial set of objectives that are then taken through the economic and social assessment process. At the end of this process, some or even all of the initial draft objective values may have been amended to meet social and economic imperatives. These agreed amendments to the draft water quality objectives then become the final water quality objectives, which are the basis of management actions.

Water Quality Objectives in the NWQMS framework are the same as Resource Condition Targets for relevant matters for targets in the NAP/NHT program frameworks.

Additional resources

Fill in this Microsoft Excel table with your chosen EVs and Indicators. Then you can fill in the cells with guideline values. Choose the most stringent guideline value (and hence the draft water quality objective).
This document Water Quality Targets Online: a handdbook provides an example of the above table filled out (Department of Environment and Heritage).

The following examples provide information and objectives for specific states or regions

New South Wales


South Australia