Why Is Turbidity Important?


Share This Post

Turbidity is an important indicator of suspended sediments in water, the presence of pathogens, bacteria, and other contaminants, which can negatively affect aquatic life and water quality.

Turbidity refers to the haziness or cloudiness of a liquid, such as water. These conditions are caused by suspended solids or tiny particles that are too small to be seen by the naked eye. This is why a turbidity sensor is required in a wide range of industries and applications. 

Why Is Turbidity Important In Water Quality?

Measuring turbidity is important when measuring the quality of water. Turbidity is used to indicate the presence of pathogens, bacteria, and other contaminants such as lead and mercury which are harmful to both aquatic life and human health. This is why turbidity is measured in drinking water and wastewater systems. 

In wastewater treatments, low turbidity indicates the water contains few suspended solids/particles, ensuring it is clean, and the water quality is good. If the turbidity measurement is high, it likely means the wastewater treatment system needs some attention. This is usually due to contamination in the pipes or from waste discharge, and run-off. 

Applications like surface water treatment plants measure turbidity and improve water quality by removing particles as they can affect the appearance, taste, and odor of the water. 

Why Is Turbidity Important In Drinking Water?

In drinking water, turbidity is used to indicate the presence of bacteria, pathogens, or harmful particles during the disinfection process. This makes monitoring turbidity levels crucial in water treatment plants, so the water does not exceed the safe level for human consumption. 

In addition to measuring water filtration systems, turbidity can also determine the number of contaminants/pollutants that remain in the water after it has been treated. This determines whether the drinking water filtration process has been successful.

Pathogen removal is particularly important as some pathogens, such as Cryptosporidium, have been linked to waterborne diseases. Such waterborne diseases are resistant to certain disinfectants in drinking water treatments therefore turbidity is also measured after water treatment. 

In the drinking water industry, it can also be difficult to continuously measure the number of pollutants in the water because of financial and technical limitations. This is where turbidity comes in. Turbidity is a good alternative to measure the number of pollutants in the water, which can be measured continuously in-stream, serving a great importance in water filtration systems. 

How Is Turbidity Measured In Drinking Water?

A turbidimeter is used to analyze the turbidity in drinking water. A minimum of two readings are taken to meet calibration standards and improve accuracy. A nephelometer (turbidity meter) is used, and either NTU or FTU units can be used. 

In developed countries, drinking water should have a turbidity level below 1 NTU; 0.2 NTU is what most water companies aim for. 

In developing countries or countries with low resources, the turbidity of drinking water should be below 5 NTU. 

Why Is Turbidity Important In Industrial Processes?

Measuring turbidity is important in industrial processes where particles may affect the end use of a product or ingredients used. Turbidity is widely used as a quality control measure in the beverage industry during manufacturing, particularly with wine and beer

In the beer brewing and winemaking industry, turbidity meters are used to measure the haze of beer and wine, and the concentration of suspended particles. A light beam is shone into the beer or wine sample, and the light is scattered by present particles. The greater the turbidity measurement, the cloudier the wine or beer.

Why Is Turbidity Important To Organisms Like Fish?

In streams and lakes, increased sedimentation and siltation occur from rainfall and erosion, which harms habitats where fish and other aquatic organisms live.

High turbidity levels (> 100,000 NTU) are lethal to fish. When fine particles enter the water, they increase turbidity, which can have harmful impacts on both freshwater, and saltwater fish. 

Impacts of high turbidity on aquatic ecosystems:

  • Clogging fish gills, causing labored breathing or death.
  • Degrading fish habitats, like spawning beds.
  • Resistance to fish diseases is reduced. 
  • Modifying natural fish movement and migrations. 
  • Reducing fish growth and successful development.
  • It reduces the amount of food and oxygen available.
  • It affects the efficiency of methods to catch fiwsh. 

Why Is Turbidity Important For Plants & Animals?

Suspended sediments can block sunlight, stunting the growth of aquatic plants and smothering aquatic animals. 

In addition to the above impacts of high turbidity, turbidity can also affect the amount of dissolved oxygen (DO) in water. When water becomes cloudy from sediment build-up, less light can reach the plants, so photosynthesis decreases. This causes a depletion in DO available for fish and other aquatic organisms. 

If the water becomes too turbid, it loses the ability to support aquatic plants and animals, therefore measuring turbidity is very important to ensure the survival of aquatic organisms. 

How Is Turbidity Measured?

Older methods such as Secchi disks are still used today, however, the best way to measure turbidity is with a nephelometer, also known as a turbidity meter. 

The units used are NTU or JTU, however, you may also come across alternative turbidity units, such as:

  • FNU 
  • FTU 
  • FAU 


Turbidity was originally used as a qualitative measurement to measure the quality of drinking water. Today, turbidity is also important to measure the quality of water in aquatic environments, and wastewater systems, and to determine the cloudiness of beverages such as wine and beer. 

If you have any questions regarding water quality or the water testing kits we have to offer, please feel free to reach out to our world-class team at Atlas Scientific, we are always happy to help!

Subscribe To Our Newsletter

Get product updates and learn from the best!

More To Explore


How To Improve Pond Water Quality & Master Maintenance

Some of the practices that can be carried out include but are not limited to the regular removal of organic debris from the pond, the introduction of aquatic plants for nutrient absorption and oxygenation, and the addition of beneficial bacteria to break down waste. Constant pH, temperature, and oxygen level checks also assist in keeping


Understanding The Role Of ORP In A Reverse Osmosis (RO) Plant

Oxidation-reduction potential (ORP) or redox monitors the condition of the reverse osmosis (RO) plant. The ORP value indicates if the membrane will be susceptible to attack by chlorine or other oxidizers, which can cause significant damage, and shorten the lifespan of the RO plant, thus increasing maintenance costs. ORP is also used to detect the

Want to learn more about our products?

Scroll to Top

To track your order please enter your Order ID in the box below and press the "Track" button. This was given to you on your receipt and in the confirmation email you should have received.