As in previous years, the Nerang estuary received a “B” grade for the 2009 Report Card.  Water quality conditions in the system were little changed with low turbidity and high DO throughout the system.  These two EHI indicators have remained fully compliant with QWQ guidelines for the past three years.  The poorest water quality compliance mainly occurred in the upper reaches of the estuarine system and was for TP with 61% compliance in 2008/2009 compared with 62% in 2007/2008.

Only about 6% of the Nerang estuary's riparian habitat remains unmodified with the majority developed for urban uses.  Much of the intertidal zone in the system has also been heavily modified to provide retaining walls for extensive canal development. This has left the Nerang estuary with the poorest percentage of unmodified riparian habitat of all the estuaries monitored by the EHMP and severely reduces its BHR and therefore Report Card grade.

Abbreviations glossary | Indicators and methods

ECOSYSTEM HEALTH INDEX (EHI)

The EHI is a measure of the proportion of a reporting zone that complied with the water quality objectives for key indicators monitored as part of the Ecosystem Health Monitoring Program. The water quality objectives are defined in the South East Queensland Regional Water Quality Management Strategy (2001).

• EHI 1 = 100% of area complies with the environmental objectives.
• EHI 0 = 0% of the area complies with the environmental objectives.

BIOLOGICAL HEALTH RATING (BHR)

The Partnership's Scientific Expert Panel has endorsed a change to the BHR in 2006-07 which increase the BHR from 20% to 30% of the Report Card Grade.

The reason for the change is the implementation of the Riparian Assessment Program (RAP) which will comprise 15% of the total grade (half of the BHR). The other BHR indicators will make up the last 15%

The data from the riparian assessment is available as PDF document.