how much turbidity should be in water

Introduction

Water is a vital resource that is required by humans for survival. However, it is prone to contamination, and turbidity is one of the factors that affect its quality. Turbidity is the amount of suspended particles that are present in the water, which affects its clarity. The existence of these particles impedes the absorption of light, making it difficult to see through the water. In this article, we will take a closer look at turbidity and how much of it should be present in water.

What is Turbidity?

Turbidity is determined by measuring the amount of light that is scattered or absorbed by the suspended particles in the water. The particles could be organic or inorganic matter, such as clay, silt, plankton, or microscopic organisms. The measurement is usually done in Nephelometric Turbidity Units (NTUs).

Why is Turbidity Important?

High turbidity levels in water could be an indication of the presence of harmful substances such as bacteria, viruses, or chemicals. These substances could affect the health of humans and animals that depend on the water for survival. Additionally, the particles could also impede the effectiveness of water treatment processes. Therefore, it is essential to monitor and control the amount of turbidity in water sources.

Recommended Turbidity Levels

The World Health Organization (WHO) recommends a maximum allowable turbidity level of 5 NTUs in drinking water. However, it is important to note that the recommended level depends on the purpose of the water. For instance, drinking water requires a lower turbidity level than swimming pool water. In general, the recommended values are as follows:

- Drinking water: less than 5 NTUs

- Swimming pool water: less than 1 NTU

- Lakes and rivers: less than 50 NTUs

- Wastewater: less than 25 NTUs

The Importance of Monitoring Turbidity Levels

Monitoring the turbidity levels in water sources is essential for the following reasons:

1. To ensure compliance with regulatory standards: Water treatment plants must ensure that they meet the regulatory standards set by the local government or other applicable agencies. These agencies set specific turbidity limits for drinking water, and failure to meet these standards could result in fines or loss of operating licenses.

2. To ensure the effectiveness of water treatment processes: High turbidity levels could affect the efficiency of the water treatment processes, resulting in the presence of harmful substances in the water.

3. To protect human health: Turbidity could indicate the presence of harmful substances, and failure to monitor and control the levels could result in adverse health effects.

Controlling Turbidity Levels in Water

Several methods can be used to control the turbidity levels in water, including the following:

1. Coagulation and flocculation: Coagulation involves the addition of a coagulant that attracts the suspended particles in the water, causing them to clump together. Flocculation involves stirring the water to facilitate the agglomeration of the clumped particles, making them easier to remove through filtration.

2. Filtration: Filtration involves the removal of suspended particles in the water through the use of a porous medium. The filter medium could be sand, gravel, or carbon.

3. Sedimentation: Sedimentation is the process of allowing the suspended particles to settle at the bottom of a tank before the water is pumped out. The particles settle due to the force of gravity.

Conclusion

Turbidity is an essential measure of water quality that needs to be monitored and controlled for the safety and health of humans and animals. The recommended turbidity levels depend on the purpose of the water. Water treatment plants should implement effective methods to control the levels, including coagulation and flocculation, filtration, and sedimentation. Regular monitoring of turbidity levels is necessary to ensure compliance with regulatory standards and maintain the effectiveness of water treatment processes.