Turbidity is a measure of water’s lack of clarity. Water with high turbidity is cloudy, while water with low turbidity is clear. The cloudiness is produced by light reflecting off of particles in the water; therefore, the more particles in the water, the higher the turbidity.

Many factors can contribute to the turbidity of water. An increase in stream flow due to heavy rains or a decrease in stream-bank vegetation can speed up the process of soil erosion. This will add suspended particles, such as clay and silt, to the water.

Runoff of various types contains suspended solids that may add to the turbidity of a stream. Agricultural runoff often contains suspended soil particles. Other types of runoff include industrial wastes, water treatment plant effluent, and urban runoff from parking lots, roads, and rooftops.


In this experiment, you will use a Turbidity Sensor to measure the turbidity of a water sample.