What is wastewater and how is it classified?

When we talk about wastewater, we are referring to all types of water that have been negatively affected by human action . In this way, those waters that, due to natural causes, are not suitable for consumption or, for example, also all the waters that, having been affected by the action of man, are also excluded.

In this sense, wastewater is all those waters that have been used in domestic and urban environments, in industries and livestock, as well as natural waters that, by accident or malpractice, have been mixed with the previous ones. In this way, we find that wastewater is water but, in addition to water, it also contains a large number of pollutants , either solid or dissolved in the same water.

Regarding the pollution that wastewater can carry, it must be said that it is a variety almost as wide as the actions that human beings can perform on water. You can find chemical products from domestic use (soaps, detergents, cosmetics, etc.), solid products (toilet paper, “disposable” cotton wipes, plastics of various sizes, etc.), heavy metals and highly pollutants from the industry (lead, zinc, mercury, cadmium, bromine, etc.), and also organic remains, coming mainly from fecal matter and urine.

In this other AgroCorrn article you can learn about the Causes and consequences of water pollution .

When it comes to classifying wastewater, we are going to find that there are different systems to do it. This is due to the value that we take as a reference. In this way, wastewater can be classified according to the amount and type of chemical substances they carry, according to their bacteriological characteristics, according to the relationship between water and suspended matter and dissolved matter, or, which is usually the most important parameter. common to all, according to their origin.

Classifying wastewater according to its origin has an advantage over other systems, which is simply that it is a much simpler method to work with when classifying. In fact, the rest of the methods require a series of scientific and study materials that allow us to analyze the quality of the wastewater we are dealing with. In this way, they are very useful classification systems, but within the scientific and environmental field.

When it comes to cataloging wastewater we will also be able to find different types of classification. However, the most common of all is the one that divides 4 types of wastewater (although these may then present their own internal categories).

Domestic or urban wastewater

This type of wastewater is the one that comes to mind first when we think about it, since it is a type of wastewater with which we are in contact every day. This type of wastewater is the result of the use of water in homes and urban centers , where a large number of businesses or workplaces are also concentrated. It is a wastewater that is especially high in organic contaminants and settleable solids , as well as bacteria. It is the water we dispose of when we flush the toilet, when we shower, when we use the kitchen sink or even the water in swimming pools.

Industrial wastewater

This type of residual water is the one that results from the processes that are carried out in the secondary sector of the economy, that is, that referred to industrial activities . This includes the water that is discarded from factories, energy production plants or any other activity that is destined to the manufacture of consumable products or manufactured products. This type of wastewater is characterized by containing a high level of polluting components such as heavy metals , among which would be lead, nickel, copper, mercury, or cadmium among many others. Likewise, it is also wastewater that contains huge amounts of artificial chemical elements of a very wide variety.

For example, here you can consult the Pollution of the textile industry .

Wastewater from agriculture and livestock

This type of wastewater is less frequent in agriculture, since most of it is used for irrigation, although it is true that some crops, as well as activities aimed at the treatment of certain agricultural products, make use of abundant water and produce wastewater.

However, the vast majority of wastewater from the primary sector comes from livestock, especially intensive livestock . These waters contain high levels of pollutants derived both from certain chemicals that are used to raise livestock and, especially, those derived from animal slurry, that is, fecal waste and urine from animals that remain in stables. . These pollutants are very dangerous, since they can affect the fertility of the soils, being able to convert a fertile soil into a complete wasteland due to the toxicity and saturation of the fecal particles they contain.

Wastewater derived from acid rain

Acid rain is a type of wastewater that is often overlooked by most people. Despite this, it constitutes a true example of residual water generated by the action that humans have in the atmosphere. This type of wastewater is produced by the effect of rain by dragging the pollutants present in the atmosphere, especially in urban centers, which reach the ground and pollute it. Most of this water, taking place in cities, ends up in the public sewer, where it joins with domestic or urban wastewater.

If you want to read more articles similar to What is wastewater and how is it classified , we recommend that you enter our Pollution category .