What Can't Water Treatment Plants Filter?

Water treatment plants are responsible for ensuring the clean and safe supply of drinking water to communities. They use a combination of physical, chemical, and biological processes to remove impurities and contaminants from raw water sources. However, there are certain substances that cannot be effectively filtered through these processes. Here are some of the things that water treatment plants may struggle to remove:

Microplastics

Microplastics are tiny plastic particles that measure less than 5 millimeters in diameter. They are often found in water sources due to the breakdown of larger plastic products, such as bottles and bags. Because microplastics are so small, they can be difficult to filter out of water. Traditional water treatment methods such as coagulation, flocculation, and sedimentation are not effective at removing microplastics. Some researchers suggest that treating water with advanced oxidation processes or membrane filtration might be more successful.

Pesticides and Herbicides

Many agricultural areas rely on pesticides and herbicides to control pests and maximize crop yields. However, these chemicals can easily enter the water supply through runoff from nearby fields. Water treatment plants typically use adsorption or oxidation to remove these types of contaminants. However, certain herbicides, such as glyphosate, can be particularly difficult to remove. They may require specialized treatment processes, such as activated carbon adsorption combined with advanced oxidation.

PFOA and PFOS

Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) are chemicals that were once widely used in consumer products such as non-stick cookware and stain-resistant fabrics. However, these chemicals are persistent and do not break down easily in the environment. As a result, they have become widespread contaminants in water supplies. Water treatment plants can use processes such as granular activated carbon adsorption or reverse osmosis to remove PFOA and PFOS. However, these processes can be expensive and may not be available in all treatment plants.

Viruses

Viruses are tiny infectious agents that can cause a range of illnesses, from the common cold to more serious diseases like hepatitis and HIV. While water treatment plants are designed to remove many types of harmful bacteria, viruses can be particularly challenging to treat. Some water treatment plants use chlorination or ultraviolet radiation to control viruses. However, these methods are not always effective against all types of viruses. Additionally, some viruses may be resistant to these disinfection methods, making it difficult to ensure that drinking water is completely free from viruses.

Conclusion

Water treatment plants play a critical role in providing communities with clean and safe drinking water. However, there are certain contaminants that are difficult to remove through traditional treatment processes. As new technologies and techniques are developed, it is important for water treatment plants to stay up-to-date with the latest methods for removing contaminants from drinking water sources.