One of these water samples is more turbid than the other!Scientifically speaking, turbidity is the measure of the degree to which water loses transparency due to the presence of suspended particulates. The higher the turbidity level, the more opaque (or murky) the water appears to be. Materials that cause high turbidity include clay, silt, algae and phytoplankton. Turbidity in urban lakes and ponds tends to increase following periods of heavy rainfall, often due to runoff from within the watershed. High turbidity can also be caused by algae growth and die-off.
Turbidity & water quality
A high turbidity level in a lake is sometimes merely an aesthetic issue. Water clarity naturally varies throughout the year as cycles of vegetation growth and decomposition occur. Some moderate turbidity can actually be desirable, as phytoplankton serves as a food source for microscopic animals and some fish, and improves water quality by producing dissolved oxygen. However, persistently high turbidity levels can cause problems and the causes should be investigated.
Controlling turbidity
The best method for reducing turbidity levels, when indicated, depends on the cause of the elevated turbidity. Green or brownish-green water with poor clarity is usually caused by exacerbated algae and phytoplankton growth, a result of excessive nutrient build-up. An algal “bloom” can cause a soupy look and bright green color. Muddy brown or reddish-brown water can indicate sediment influx from erosion and runoff; dredging may be warranted, along with an identification of the source to reduce future build-up.
A sudden, drastic change in water color or clarity (unless the change in clarity is directly attributable to a storm event) and/or a foul odor warrants a call to a professional.
