What are water quality problems often attributed to?

Excess nutrients in water is a significant contributor to water quality problems, particularly from agricultural runoff. When fertilizers are applied to crops, they often contain nitrogen and phosphorus, which can leach into nearby water bodies during rain events or through irrigation practices. This excess nutrient load can lead to eutrophication, where nutrient overload causes algal blooms that deplete oxygen levels in the water, harming aquatic life and disrupting ecosystems.

While lack of vegetation, soil erosion, and inadequate irrigation can also impact water quality, the direct and immediate association of excessive nutrients from fertilizers makes that option particularly relevant. Vegetation can help filter nutrients before they enter waterways, soil erosion can contribute to sediment and nutrient runoff, and inadequate irrigation may lead to inefficient fertilizer application, but none are as directly connected to the immediate changes in water quality as the presence of excess nutrients.