Water Turbidity Definition
The turbidity of a water sample is a measure of the extent to which the intensity of light passing through water is reduced by the suspended matter.
The turbidity of water is based upon a comparison of the amount of light passing through a given water sample with that passing through a standard sample. Traditionally, Turbidity is measured in standard units defined in terms of the depth of water to which a candle flame can be clearly distinguished.
The sources of turbidity in natural water are attributable to suspended and colloidal material, the effect of which is to disturb clearness and diminish the penetration of light. Turbidity may be caused by several factors such as microorganisms and organic detritus, silica and other sands and substances including zinc, iron and manganese compounds, clay or silt. In addition, the result of natural processes of erosion or as waste from various industries such as mining, dredging, logging and others. In some of the literature, the terms “turbidity and suspended solids” are sometimes used synonymously. This can produce errors in data interpretation if a correction function is not developed to adjust the turbidity value to represent the concentration of suspended solids. The correction function should be calculated for each water quality station because the function may vary from location to location. As a final comment, you will have more reliable water quality data if turbidity and suspended solids are retained as independent parameters.