Editing Turbidity (section)

==Treatment==
{{Unreferenced section|date=August 2022}}
Turbidity is commonly treated using a settling or filtration process, or both settling and filtration. Depending on the application, [[flocculants]] may be dosed into the water stream to increase the effectiveness of the settling or filtration process.<ref name="AWWA">{{cite book |title=Water Treatment, Grade 1|date=2016 |publisher=American Water Works Association |location=Denver, CO, USA}}</ref><ref name="SARAI">{{cite book |title=Water Treatment Made Simple For Operators |author=Darshan Singh Sarai |date=2006 |publisher=John Wiley}}</ref> [[Potable water]] treatment and municipal [[wastewater]] plants often remove turbidity with a combination of settling tanks, [[media filter|granular media filtration]], and [[clarifier]]s.

[[In-situ water treatment]] or direct dosing for the treatment of turbidity is common when the affected water bodies are dispersed (i.e. there are numerous water bodies spread out over a geographical area, such as small drinking water reservoirs), when the problem is not consistent (i.e. when there is turbidity in a water body only during and after the wet season) or when a low cost solution is required. In-situ treatment of turbidity involves the addition of a reagent, generally a [[flocculant]], evenly dispensed over the surface of the body of water. The flocs then settle at the bottom of the water body where they remain or are removed when the water body is drained. This method is commonly used at [[coal mine]]s and coal loading facilities where stormwater collection ponds have seasonal issues with turbidity. A number of companies offer portable treatment systems for in-situ water treatment or direct dosing of reagents.

===Reagents===
There are a number of [[chemical reagent]]s that are available for treating turbidity. Reagents that are available for treating turbidity include [[aluminium sulfate]] or [[alum]] (Al<sub>2</sub>(SO<sub>4</sub>)<sub>3</sub>·nH<sub>2</sub>O), [[ferric chloride]] (FeCl<sub>3</sub>), [[gypsum]] (CaSO<sub>4</sub>·2H<sub>2</sub>O), poly-[[aluminium chloride]], long chain [[acrylamide]]-based [[polymer]]s and numerous proprietary reagents.<ref>Earth Systems, Clear Solutions newsletter - Focus on Turbidity [http://www.earthsystems.com.au/wp-content/uploads/2012/02/ClearSolutions_No1_2003.pdf] 2003.</ref> The water chemistry must be carefully considered when chemical dosing as some reagents, such as alum, will alter the [[pH]] of the water.

The dosing process must also be considered when using reagents as the [[Flocculation|flocs]] may be broken apart by excessive mixing.