Objectives – It is important that water quality assessments are not simply formulaic with some water quality standard (such as the ANZECC Guidelines) taken as an impenetrable barrier, where below the standard is perfectly good in all conditions and above the standard is a disaster for the environment. The number of samples, the location that the samples are collected from, the time of sampling, the volume of flow (Hydrology and Hydraulics page ) and the water quality in the receiving waters must all be taken into account when making a water quality assessment. In some cases this may need to be explained to Council or EPA.
ANZECC Guidelines – Page 1-1 of the Guidelines states:
These Guidelines should not be used as mandatory standards because there is significant uncertainty associated with the derivation and application of water quality standards.
The simple way to think about water quality is to just remember one number for each analyte. Below that number is good, above that number is bad. Simple doesn’t mean accurate or appropriate, which is the reason that the ANZECC Guidelines have written on the very first page of their thousand page document that the guidelines should not be used as simple mandatory standards.
The NSW Department of Environment and Heritage have published a document entitled “Using the ANZECC Guidelines and Water Quality Objectives in NSW,” with the goal of assisting technical practitioners applying the ANZECC Guidelines in NSW.
The ANZECC Guidelines acknowledge that different levels of protection may be appropriate for different water bodies. The guidelines specify three levels of protection, from stringent to flexible, corresponding to whether the condition of the particular ecosystem is:
- of high conservation value
- slightly to moderately disturbed, or
- highly disturbed
The policy in NSW is that the level of protection applied to most waterways is the one suggested for ‘slightly to moderately disturbed’ ecosystems.
Sampling – The timing, location and number of samples and the analytes to be assessed at the Lab are all critical to getting the most accurate picture of the water that is of interest. This naturally leads to a cost / benefit analysis of the sampling and analysis program. There is no sense in getting five samples and testing 20 analytes on 1000 litres of water in Sydney, because it would be cheaper to send it straight to the Lidcombe Liquid Waste Treatment Plant.
Water Quality Projects
Expert Witness Land and Environment Court
Brickworks – Punchbowl Groundwater Quality at Reclaimed Landfill Site
Brickworks – Punchbowl Water Quality in Sedimentation Pond
Ecoflex Water Quality assessment of recycled tyres in wet conditions over time (link to paper for Ecoflex)
Treatment Plant Optimisation – West Wyalong Treatment Plant, Bland Shire Council
Teys Wagga Wagga – Nutrient Loading for Treated Effluent Irrigation