Handy guide – commonly tested natural waterway water quality parameters
Water Quality 101 – what exactly is in that local creek?
Waterform is all about stormwater treatment, water reuse, tradewaste and more, right? Well, yes – however we also take great interest in the water quality in our natural creeks and rivers that criss-cross Australia which are so essential to life, and of course wastewater and dirty stormwater impact these amazing ecosystems the most. Here are some commonly tested water quality parameters and the reasons these need to be tested.
Turbidity.Turbidity is a measure of the amount of suspended particles in water. High turbidity is deleterious to many aquatic organisms and indicates excessive erosion in the watershed.
Conductivity. Conductivity provides an estimate of the amount of salts dissolved in a water body. While some salt content is beneficial, high levels are harmful. An increase in conductivity beyond normal levels may indicate pollution from agricultural runoff or other sources.
pH. pH is a measure of hydrogen ion concentration and indicates the relative acidity or alkalinity of water. pH significantly higher or lower than the neutral value of 7 is deleterious to most aquatic life. pH measurements outside of a certain range may indicate problems such as excessive decay of organic matter (eutrophication) or acid mine drainage.
Nitrate (NO3). High nitrate content, typically from wastewater plant discharge and agricultural runoff, is problematic because it stimulates planktonic and algal growth, which can lead to eutrophication.
Phosphate (PO4). Phosphate is similar to nitrate in terms of sources and effects.
Dissolved oxygen. Oxygen is necessary for all forms of life. As dissolved oxygen levels in water drop below 5.0 mg/l, aquatic life is put under stress. Dissolved oxygen is reduced when excessive bacterial growth uses up the available oxygen.
Total Coliform and E. coli bacteria. The concentrations of these indicator organisms can be used to assess the level of bacteria contamination in local waterways and the potential risk to humans recreating in these waterways.
Water temperature. This is one of the most important parameters because of its influence on other water chemistry parameters such as dissolved oxygen levels, pH, rates of nutrient cycling, and contaminant transformation rates. Water temperature also regulates many aquatic organism functions including growth, reproduction, development, habitat preference, and competition.