Answer:
This question is incomplete since you did not provide an specific case where this is happening. Anyway, I will give you an explanation that will be useful for you to understand why this happens.
Step-by-step explanation:
Turbidity is due to the presence of small particles in the water that are difficult to filter or remove by oxidation. Turbid water is due to algae growth, high pH, or poor filtration.
These particles cause the water to stop being clear. The more particles that are suspended over the water, the more cloudy it will be.