Influent or Effluent: How to Tell Them Apart
These two terms refer to a flow of water in or out. One is the feed water and the other is the discharge of water.


This parameter refers to the input water to a water treatment system. In other words, when water needs to be treated before or after use, it is referred to as influent.

- For your information, the term influent comes from the Latin word influentem, which means "flowing".

As implied above, influent may be the plant's feed water prior to its use, but it may also refer to the wastewater generated by the manufacturing process. On the other hand, to be considered as influent, the wastewater must be treated before being discharged. In this case, it will be considered as influent before it enters the treatment system.



The Effluent

Simply put, effluent can be defined as a stream of water flowing from a source. This means that effluent refers to the water output of a water treatment system.

- Again for information purposes, the term effluent comes from the Latin effluens which means "to flow".

We remind you that the effluent can be the water produced by a water treatment system before its use. The term effluent can also refer to industrial effluents, which are discharges from industries.



The Importance of Monitoring Influent and Effluent

Understanding and monitoring these parameters is a way to keep an eye on the proper functioning of your water treatment system. For example, if a reverse osmosis system has a 20% rejection rate. For every 100 gallons of influent, 80 gallons of effluent should be produced. When fluctuations between influent and effluent is perceived, several options may be the cause. Fluctuations in flow may be due to fouling of the osmotic membranes or they may be due to a breakdown or problem in the equipment such as fouling in the piping.


In short, understanding and monitoring these parameters makes it easier to monitor your equipment.

The Distillation of Water
Distilled water is defined as water that is free of all minerals and microorganisms.