What might happen to water quality after heavy precipitation events?

Heavy precipitation events can lead to a deterioration of water quality, and the reasoning behind this is tied to several environmental factors. During rainfall, runoff can carry various pollutants from land surfaces, such as fertilizers, pesticides, sediment, and other contaminants, into nearby water bodies. This influx of pollutants can overwhelm the capacity of natural filtration systems, such as wetlands or soil, leading to temporary spikes in pollution levels.

Additionally, heavy rainfall can erode stream banks and disturb sediment in rivers and lakes, contributing to increased turbidity. The combination of these factors often results in a decline in water quality, which can have significant effects on aquatic ecosystems, drinking water sources, and overall environmental health.

The other choices do not accurately reflect the typical consequences of heavy rainfall on water quality. For instance, the idea that water quality remains unchanged is misleading, as significant rainfall often disrupts the balance of pollutants. While dilution may occur in some contexts due to increased water volume, it is generally insufficient to offset the influx of pollutants. Natural filtration through soil can help mitigate some effects but is often compromised during intense rainfall events.