Turbidity is measured using a secchi disk, a Turbidometer, a Colorimeter or a Color Scale. A secchi disk is a plastic, weighted plate that is lowered into the water. The depth at which it is no longer visible indicates water clarity. A Turbidometer and Colorimeter are electronic devices that measure the amount of light that passes through a water sample. Less light can pass through tubid water than clear water. Finally, the Color Scale uses a series of colors to measure the clarity of water, from clear blue to muddy brown.
