| Water quality measure | Assessment grade | Confidence | ||||
|---|---|---|---|---|---|---|
| Very poor | Poor | Good | Very good | In state grade | In trend grade | |
| Conductivity | Stable | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| pH | Stable | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| Dissolved oxygen | Stable | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| Turbidity | Improving | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| Total phosphorus | Improving | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| Total nitrogen | Improving | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| Suspended solids | Improving | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| Faecal coliforms | Improving | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| Chlorophyll-a | Improving | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
| Overall surface water quality score | Improving | Adequate high-quality evidence and high level of consensus | Adequate high-quality evidence and high level of consensus | |||
Note: State is based on the number of sites that exceed water quality guidelines. Very good = 1–10%; Good = 11–25%; Poor = 25–49%; Very poor = 51–100%. Trends are classified as improving (up arrow) or declining (down arrow) if there has been a 5% or greater change in the frequency that guideline levels are exceeded relative to the 2007–2011 assessment period. The overall water quality score (in bold) is the average of all measures. Overall score is the average of all water quality grades.