During times of hard rain, nutrient rich soil runs off into streams/rivers. This abundance of nutrients triggers the growth of algae. This algae can form a thick film on the water’s surface blocking sunlight from reaching the bottom. Aquatic plants are then hindered from photosynthesis depleting oxygen levels which directly affects fish health.
Below are examples of clear and turbid (murky and cloudy) water samples. Water can become turbid in a variety of ways. As before hard rains can carry sediment into nearby streams/rivers. In areas where vegetation had been removed, such as farms or construction sites, runoff can be more detrimental to aquatic ecosystems. Livestock that wade in streams can also aggravate sediment making water turbid for shorter periods of time. Fishes are unable to see in such waters, impeding there ability find food or shelter from predators. Fine sediment also gets into there gills making it harder for a fish to breath.
Turbid water affects:
Temperature by blocking sunlight to warm water
Visibility decreasing predator evasion and ability to find food
Increases pH
Decreases available oxygen