Surface runoff occurs when rainwater pools on the surface after infiltrating the soil to its maximum capacity. It flows across the land into low points and bodies of water, carrying pollutants from urban and agricultural areas that can harm the environment, wildlife, and water quality. Increased urbanization reduces groundwater recharge and exacerbates drought by preventing water absorption, impacting farmers and communities that rely on well water. Contaminants transported by surface runoff threaten aquatic species through fish kills, population imbalances, and interference with reproduction. Simple actions like proper pesticide use, cleaning up pet waste, and recycling motor oil can help reduce pollutants entering watersheds via surface runoff.