What can be a major source of groundwater contamination?

Agricultural runoff is a significant source of groundwater contamination primarily because it often contains fertilizers, pesticides, and other chemicals that are used in farming practices. When it rains or when irrigation occurs, these substances can be washed off the fields and enter nearby waterways, and over time, they can seep through the soil and contaminate groundwater supplies.

The nutrients from fertilizers, especially nitrogen and phosphorus, can lead to issues like nutrient loading in water bodies, resulting in algal blooms that disrupt aquatic ecosystems. Additionally, pesticides can have toxic effects not only on target pests but also on surrounding flora and fauna and can persist in the environment, leading to long-term contamination of groundwater sources.

Thus, the connection between agricultural practices and the quality of groundwater is critical, highlighting the importance of implementing best management practices in agriculture to mitigate these risks and protect water quality for all users.