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What is turbidity?
It is the measurement of lack of water clarity that is measured in NTU or JTU.

What factors influence the turbidity of water?
1. Turbidity is the result of suspended solids in the water that range from clay, silt, and plankton, to industrial wastes and sewage. The lower the turbidity, the clearer the water is.
2. High turbidity may be caused by soil erosion, waste discharge, urban runoff, flooding, dredging operations, channelization, increased flow rates, algae growth, or even too many bottom-feeding fish (such as carp) that stir up bottom sediments.

What is the optimal amount of turbidity of water for most aquatic plants and animals?
1. A normal range for a turbidity of a river has not been established.
2. Turbidity of drinking water can range from 0.5-1.0 NTU, but should never exceed 1.0 NTU.
3. Turbidity that exceeds 5.0 NTU can be easily detected.
4. A turbidity of 0-10 JTU is considered normal.

What factors are affected by the turbidity of your watershed?
1. Turbid water’s particles absorb the sun’s rays, which cause the water temperature to increase and dissolved oxygen to decrease. This may negatively affect the quality of aquatic life.
2. If the water is too turbid, it loses the ability to support a wide variety of aquatic plants and animals.
3. Suspended solids reduce the amount of light that can pass through the water. As less light penetrates the water, photosynthesis slows, releasing less oxygen into the water. If light is blocked to bottom-dwelling plants, they will cease to produce oxygen and will eventually die. As they decompose, bacteria will use up more oxygen from the water. This will decrease the amount of dissolved oxygen concentration in the water and may cause stress or even death to aquatic organisms that need high amount of oxygen to survive.
4. Suspended solids can clog and damage the fish’s gills.
5. Turbid water can interfere with the ability for fish to find food.
6. Suspended solids can prevent proper egg and larval development. As particles of silt, clay, and other organic materials settle to the bottom, they can suffocate newly hatched larvae.
7. Settling sediments can fill in the spaces between rocks, which could have been used to provide homes for aquatic organisms.


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