Water Quality Monitoring
What is Measured and Why
Attribute | Why We Measure It | Causes Of Elevated/Depleted Levels | Potential Mitigation |
Water Temperature | High water temperatures effect the survival of aquatic insects and fish. | Lack of riparian shading Time of day and season | Riparian planting to provide shade |
Dissolved Oxygen | Low dissolved oxygen levels effect the survival of aquatic insects and fish | Algal cover Time of day and season | Reduce input of organic matter (stock access to waterways) Decrease nutrient input and provide shade to reduce algal cover |
pH | Deviations from natural pH values can impact the growth and reproduction of fish, and in extreme cases cause fish death | Photosynthetic activity of aquatic plants | Reduce input of organic matter (stock access to waterways) Decrease nutrient input to reduce algal cover |
E. coli | E. coli are an indicator for faecal contamination, which has negative effects on aquatic ecosystems and presents a health risk to recreational users. | Faecal contamination (influenced by stocking intensity, duration of grazing, type of livestock, land slope and soil type) Poorly maintained/managed or damaged wastewater systems | Limit stock access to waterways Planting dense riparian vegetation can act as a buffer |
Dissolved Nitrogen, Nitrate and Ammoniacal Nitrogen | These are the forms of nitrogen (N) that are easily taken up by plants. High concentrations lead to excessive algae growth, which impacts aquatic habitat quality and oxygen levels. High concentrations are toxic to aquatic life. | Leaching (any nitrogen in animal waste or nitrogenous fertilizer applied to land not taken up by vegetation is carried into groundwater). Cattle urine Fertilizer and wastewater application Leachate from storage of large amounts of organic material Land use | Limit stock access to waterways (including swales and wetlands) Decrease fertiliser application of high N fertiliser. Decrease spraying of bank and in stream vegetation. Riparian planting to increase N uptake. |
Dissolved Reactive Phosphorus | These are the forms of phosphorus (P) that are easily taken up by plants. High concentrations lead to excessive algae growth, which impacts aquatic habitat quality and oxygen levels | Sediment from surrounding land surfaces and stream bank erosion. Geology | Limit stock access to waterways (including swales and wetlands) Riparian planting to filter sediment and decrease bank erosion. Decrease fertiliser application of high P fertiliser. |
Turbidity | Turbidity is a measure of sediment in the water. Fine sediment affects the growth of aquatic insects and fish. When sediment settles on riverbeds, it smothers habitats and degrades food sources. Reduced water clarity also impacts on the recreational values of rivers. | Flood flows Surface runoff of fine sediment from surrounding land surfaces especially from slips or bare land Removal of vegetation along the edges of water ways Geology | Riparian planting Maintaining vegetation on the edges of water ways Limit stock access to reduce damage to stream banks. Reduce on-farm and track erosion. |
Related links
State of the Environment Reporting: Surface water monitoring
