High total suspended solids (TSS) in water are primarily caused by particles of dirt, sediment, and other organic or inorganic materials being washed or introduced into a water body.
Total suspended solids (TSS) refer to the small particles of solid material that remain suspended in water rather than dissolving. High levels of TSS can make water appear cloudy or murky and impact its quality.
Main Contributors to High TSS
Several factors can lead to elevated levels of TSS in water sources like rivers, streams, lakes, and oceans. These sources introduce fine particles that remain suspended.
Erosion and Sedimentation
A major cause of high TSS is the erosion of soil and land. Increased erosion of banks of rivers and streams can increase the TSS level in water. This happens when soil and rock particles are dislodged and carried into the water. The suspended particles released from dirt and soil can settle out across water and give it a murky appearance.
Runoff from land, especially during or after rainfall, is a significant driver of erosion. Runoff — when water flows through eroding soil — may also produce similar results, carrying loose soil and sediment into waterways.
Other Potential Sources
Beyond natural erosion, various human activities and environmental conditions contribute to TSS:
- Urban Runoff: Water flowing over impervious surfaces like streets, parking lots, and rooftops in urban areas picks up dirt, debris, and pollutants, carrying them into storm drains and eventually waterways.
- Agricultural Runoff: Practices like tilling and inadequate soil conservation can lead to soil erosion from fields. This eroded soil, often containing fertilizers and pesticides attached to particles, enters nearby water bodies.
- Construction Activities: Construction sites can be significant sources of sediment if proper erosion control measures are not in place. Disturbed soil is easily washed away by rain.
- Industrial Discharge: Some industrial processes release wastewater containing suspended solids into water bodies.
- Wastewater Treatment Plants: While treated, effluent from wastewater treatment plants can sometimes contain residual suspended solids, especially if treatment is not optimized.
- Natural Decomposition: The breakdown of organic matter, such as leaves, plants, and dead organisms, can contribute fine suspended particles to the water.
- Bank and Shoreline Disturbances: Activities like dredging, boating (which can stir up bottom sediments), and removing vegetation along banks can increase TSS.
These sources collectively contribute to the load of suspended particles, impacting water clarity, aquatic life, and the overall health of the ecosystem.
Why High TSS is a Concern
Elevated TSS levels can harm aquatic life by:
- Reducing light penetration, which affects photosynthesis by aquatic plants.
- Clogging fish gills.
- Smothering eggs and aquatic insect larvae.
- Destroying habitat as sediment settles.
- Increasing water temperature due to increased absorption of sunlight.
High TSS can also affect drinking water treatment processes and recreational uses of water bodies.
Common Sources of High TSS
Here's a table summarizing key sources:
| Source | Description | Example |
|---|---|---|
| Erosion (Natural & Human) | Dislodged soil and sediment entering waterways. | Eroding stream banks, deforested areas |
| Runoff | Water flowing over land surfaces, picking up particles. | Stormwater from bare soil fields |
| Urban Areas | Runoff from streets, construction sites. | Sediment from construction sites |
| Agriculture | Eroded soil from farms. | Runoff from tilled fields |
| Industry/Wastewater | Discharge of process water or treated effluent. | Plant discharge, sewage treatment overflow |
| Natural Processes | Decomposition of organic material. | Leaf litter decay in streams |
Understanding the sources is the first step in implementing strategies to reduce TSS and protect water quality.
