water quality standards
Dissolved Oxygen DO
This standard refers to the amount of dissolved oxygen in the water of a water source. Higher amount of dissolved oxygen means better water quality. Low concentrations of dissolved oxygen represent organic waste pollution within the water.
Biological Oxygen Demand BOD
BOD is a measure of the amount of oxygen that bacteria such as microorganisms use to break down a variety of organic matter, such as sewage, plant leaves, grass leaves, and food waste. If the amount of organic wastes within 1 water source is high, bacteria will be in greater numbers and use oxygen. Oxygen demand will be high in such polluted conditions. Thus the BOD value will be high. With higher levels of BOD, the DO levels of water also decrease.
Chemical Oxygen Demand COD
It is the amount of oxygen that is obtained by the degradation of organic chemical compounds present in the residual water. Water bodies into which effluents from chemical factories reach have high COM values.
Most Probable Number (MPN)
There is pollution of organic wastes in the water, in which a large number of bacteria like E. coli and coli form are found. With the help of MPN test, E. coli and coli form organisms can be identified. The number of these organisms present in the water body can be pre-declared statistically by MPN method. coli form organisms are found in human intestines. Their presence in water is an indicator of waste. Higher values of MPN are found in polluted water.
Totally Dissolved Solids (TDS)
The amount of dissolved solids and salts in water is measured by testing TDS and salinity quantity. The dissolved substances that degrade water quality are calcium, phosphorous, iron sulphate, carbonates, nitrates, chlorides and other salts. Heavy metals also fall in this category. Water quality deteriorates due to high amounts of TDS.