What is Turbidity in Water?

Turbidity is measured using an optical device that detects particles in the water. A light is shone through the water, and the device measures how much of the light bounces back to the sensor. This allows us to determine particle concentration, expressed in Nephelometric Turbidity Units (NTU).

Both natural and human-driven factors can cause turbidity in water. Environmental influences, such as heavy rainfall or flooding, can wash sediments, soil, and organic matter into rivers and lakes, increasing the cloudiness of water. Algae blooms, often spurred by pollution, can further contribute to turbidity as decaying algae release organic particles.

Human activities are also significant contributors. Agricultural runoffs, carrying fertilisers and pesticides, often increase sedimentation and turbidity in nearby water supplies. Industrial activities like mining and the discharge of untreated wastewater can also introduce pollutants and sediments into the water, reducing its clarity. Urban runoff, including oil, chemicals, and debris from roads and buildings, further exacerbates turbidity.

Despite water treatment processes designed to clean water from sources like rivers before it reaches our taps, some particles can still make it through. This might happen when treatment systems are overwhelmed, such as during heavy rainfall or flooding, or the filtration systems are insufficiently maintained. Fine particles like clay, silt, or certain organic materials can occasionally bypass the cleaning stages, leading to increased turbidity in drinking water.

Depending on the cause, water with high turbidity can pose health risks. For instance, algae or bacteria can lead to illness, as these particles may harbour harmful pathogens. Some water with turbidity can still be safe to drink if it’s been properly treated. However, one of the primary concerns with high turbidity is the visual quality of the water. For example, a restaurant serving cloudy drinking water can create a poor impression and be less pleasant to drink. For more information about the legal requirements of drinking water, check out the workplace drinking water regulations. You can also use the gov. uk website to check the quality of your drinking water.

One of the best ways to reduce turbidity is by using high-quality water filters. BRITA water dispensers, for example, use advanced filtration technologies to reduce turbidity effectively. The nonwoven pre-filter material traps coarse particles, while the activated carbon block helps remove substances that could impair taste and odour. BRITA’s hollow-fibre membranes also filter out fine particles, removing 99.999% of bacteria and other contaminants like microplastics and cysts. For more information, see our guide on why you should have a water dispenser in your office.

Turbidity in water can impact its appearance and safety. By understanding its causes and potential health risks, you can reduce turbidity, ensuring your water is clean and refreshing. Effective filtration solutions like BRITA filters can help improve water quality and protect your health. To learn more about what’s in your water, read our comprehensive guide: The Hidden Plastic Particles in Bottled Water