(pic from http://www.epa.gov )
- Turbidity can indicate excessive soil erosion from earth-disturbing activities such as construction, agriculture, and logging.
- Turbidity often increases sharply during heavy rainfall in developed water-sheds, especially those having a relatively high proportion of impervious surface.
- Turbidity is used to monitor the erosion rates of stream banks and channels that may require additional erosion control practices.
- Not only does turbidity interfere with drinking water disinfection, but also suspended particles can provide a habitat for pathogens. The WHO (2010) recommends that the turbidity of drinking water be less than 1 NTU, but never more than 5 NTU. (Permenkes No 492 Tahun 2010, Turbidity = 5 NTU (max))
- Moderately low levels of turbidity may indicate a healthy, well-functioning ecosystem, with moderate amounts of plankton present to fuel the food chain.
- At higher level of turbidity :
- suspended particles absorb energy from sunlight, making water bodies warmer and potentially reducing the concentration of DO to stressful levels for aquatic life.
- photosynthesis of aquatic plants and algae is diminished, also decreasing DO.
- in slow-moving water, settling particle may blanket and suffocate fish eggs, benthic animals and insect larvae
- shallow lakes fill in faster to become marshland
- suspended solids can transport sorbed metals, pesticides, nutrients and other low-solubility pollutants throughout a stream system
- suspended solids can clog fish gills, reducing resistance to disease in fish, lowering growth rates and affecting egg and larval development
Eugene R. Weiner. Application of Environmental Aquatic Chemistry. A Practical Guide. Third edition. CRC Press