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Suspended Solids

Suspended Solids (SS) refers to small solid particles which remain in the water. Total Suspended Solids (TSS) are particles larger than 2 microns found in water, large enough to be held back by a filter. In comparison, Total Dissolved Solids (TDS) are particles smaller than 2 microns small enough to pass through a filter. SS measures the amount of particulate matter floating in the water. Particles in rivers, lakes and streams can include algae, organic matter, clay and other inorganic substances like minerals, salts and metals.

What Are Suspended Solids in Water?

Suspended solids are the portion of particulate matter that remains in the water. It measures a similar property like turbidity but gives an actual weight of particulate matter.

Most suspended solids are made of inorganic material, but bacteria and algae can also contribute to solid levels. Such solids include anything floating in the water like gravel, silt, sand and clay.

Are Suspended Solids Bad?

Suspended solids can clog fish gills, which either kills them or reduces their growth rate. They can also reduce light penetration, reducing the ability of algae to produce food and oxygen.

Turbidity Suspended Solids Sensor

Concerning drinking water, suspended solids can interfere with effective treatment of ensuring high water quality and drinkable water. High sediment levels can interfere with filtration and disinfection and require more chlorine to disinfect turbid water effectively.

Recreational use and aesthetic enjoyment of the water can be affected by suspended solids. For example, poor visibility from high suspended solids levels can cause danger for swimming and diving. In addition, sediment deposition can close up channels or fill up water bodies, converting them into wetlands.

One potential positive impact of suspended solids in water is how toxic chemicals like pesticides can be absorbed by the suspended solids or become complexed with them, making the toxicity less available to be absorbed by living organisms.

Suspended Solids

The Effects of High Suspended Solids Levels

High suspended solids in drinking water or wastewater can have environmental and human health effects. With water quality, high levels can decrease water’s natural dissolved oxygen levels and increase temperature. This can prevent organisms that live in water from being able to survive. High levels can also impact photosynthesis, decreasing the survival rate of plants and further decreasing oxygen levels.

Suspended solids in drinking water can affect human health. For instance, bacteria can lead to gastrointestinal issues, while pollutants can have serious health effects. In addition, common suspended solids like sand and slit may be unharmful but leads to aesthetic issues in pipes.


What is the Relationship Between Total Suspended Solids (TSS) and Turbidity?

Turbidity and Total Suspended Solids (TSS) are used interchangeably, but they are not quite the same things. Turbidity refers to water transparency, and so the more suspended solids present in the water, the less transparent it will be. While turbidity measures how well light can pass through water, total suspended solids is a quantitative measure of suspended particles in water.

Total Suspended Solids

Total Suspended Solids (TSS) are a total quantity measurement of solid material per volume of water. TSS is a specific measurement of all suspended solids, organic or inorganic, including settleable solids, and is a direct measurement of total solids in a water body. While TSS can be used to calculate sedimentation rates, turbidity cannot.

Turbidity

Turbidity is determined by the amount of light scattered off of particles, like suspended solids. Turbidity measurements can be used to estimate TDS concentration but are not exact. However, turbidity measurements do not include settled solids or bedload, sediment that rolls on the riverbed.

Water Clarity

Water clarity is related to sunlight penetration, which can also help determine the amount of suspended solids in water. While water clarity can be affected by other dissolved solids, it is the most subjective measurement of water quality compared to turbidity and suspended solids. It is often determined by human observation.

Total Suspended Solids

Total Suspended Solids (TSS) are a total quantity measurement of solid material per volume of water. TSS is a specific measurement of all suspended solids, organic or inorganic, including settleable solids, and is a direct measurement of total solids in a water body. While TSS can be used to calculate sedimentation rates, turbidity cannot.

Why Are Total Suspended Solids, Turbidity and Water Clarity Monitoring Important?

While turbidity and total suspended solids refer to particles present in the water column, turbidity and water clarity are visual properties of water-based on light scattering. All three parameters are related to water particles, directly or indirectly. While there is room in the Waka for two additional sensor upgrades, you can choose to include your own suspended solids sensor or use our preinstalled turbidity sensor to indicate suspended solids levels.


The Importance of Suspended Solid in Water Quality Monitoring

Turbidity levels can indicate suspended solids in water, and both are visible indicators of water quality. However, when measuring suspended particles specifically, it indicates the environmental impact on the water. Suspended solids can come from soil erosion, runoff, algal blooms, and more.

Some rivers and streams can have naturally high suspended solids levels, but clear water is usually an indicator of healthy water. Excessive sediment can negatively affect water quality for aquatic and human life, indicated by suspended solids and turbidity levels.

New Zealand Environmental Water Quality Monitoring with Real Time Io T Artificial Intelligence Water Monitor RW

Suspended Solids, Turbidity and Water Clarity Updates

The RiverWatch blog is the data centre for New Zealanders committed to monitoring and enhancing our waterways. Learn more about the water quality of New Zealand and our integral connection with the waters, and stay up to date with important news, research and developments.