Chemical runoff refers to the movement of harmful substances, such as fertilizers, pesticides, and heavy metals, from land into nearby water bodies. This often occurs after rainfall or irrigation, when excess chemicals wash away from agricultural fields, urban areas, or industrial sites. The runoff can contaminate rivers, lakes, and oceans, posing risks to aquatic life and human health. When chemical runoff enters water systems, it can lead to problems like algal blooms, which deplete oxygen and harm fish populations. Additionally, pollutants can accumulate in the food chain, affecting species such as fish and birds, and ultimately impacting human communities that rely on these water sources for drinking and recreation.