Turbidity is a measure of the cloudiness or haziness of a liquid, typically water. It is caused by the presence of small particles suspended in the liquid, such as clay, silt, algae, or microscopic organisms. These particles can scatter and absorb light, making the water appear cloudy or murky.

The small suspended particles that cause this murkiness in water act in a similar way to the way that the tiny droplets that make up mist, fog and clouds do. As light from the sun or moon passes through mist, fog and clouds, it is scattered in many directions. This causes the light to appear white, as all colors of the spectrum are present and seen by our eyes. That’s why clouds look white to us. In addition, larger droplets tend to scatter light more than smaller droplets, which is why clouds that are made of larger droplets appear whiter than those made of smaller droplets. Thunderstorm clouds look grey as so much of the initial light has been scattered away due to the size of the cloud and its droplets that there is less light left for us to see, so by comparison to the rest of our view, the cloud looks grey.

The particles suspended in water show the same effect, but also tend to absorb some parts of the colour too. This means that rather than appearing white, they tend to look murky and coloured. When colour isn’t absorbed by the particles however, the liquid will look white. This is why milk looks white.

Turbidity is often used as an indicator of water quality, as high levels of turbidity can indicate the presence of pollutants or other contaminants. For example, a high level of turbidity in a river or stream may indicate that there is agricultural or industrial runoff present in the water. Similarly, high turbidity in drinking water can indicate the presence of bacteria or other microorganisms that could pose a health risk.

The most common way to measure turbidity is by using a device called a turbidimeter. A turbidimeter shines a light through a sample of water and measures the amount of light that is scattered or absorbed. The higher the level of turbidity, the less light that is able to pass through the water and the more that is scattered. The results of the measurement are usually reported in units called nephelometric turbidity units (NTU).

To ensure that the water is safe to drink, it is important to keep turbidity levels low. The World Health Organization (WHO) recommends that drinking water should have a turbidity level of less than 5 NTU. Some states and countries may have different standards for turbidity levels in drinking water.

There are several ways to reduce turbidity levels in water. One common method is to use a process called coagulation and flocculation. This involves adding chemicals to the water that cause the small particles to clump together and form larger particles, which can then be more easily removed by sedimentation or filtration. Other methods include using a sedimentation basin, rapid sand filter, or a membrane filtration.

It is important to note that while turbidity is often associated with pollution, it can also occur naturally. For example, turbidity levels can be higher during certain times of the year when there is more runoff from snowmelt or heavy rains. Additionally, certain bodies of water like rivers, reservoirs may have high levels of turbidity due to natural sedimentation.

Turbidity is a measure of the cloudiness or haziness of a liquid, typically water. It is caused by the presence of small particles suspended in the liquid, such as clay, silt, algae, or microscopic organisms. High levels of turbidity can indicate the presence of pollutants or other contaminants, which can pose a health risk. It is important to keep turbidity levels low to ensure that the water is safe to drink. There are several ways to reduce turbidity levels in water like coagulation and flocculation, sedimentation basin, rapid sand filter, or a membrane filtration