Final answer:
Water runoff after a storm carries chemicals and contaminants into bodies of water, leading to water pollution through processes such as algal blooms and creating dead zones. Preventative measures include reducing fertilizer use and preserving wetlands as natural filters.
Step-by-step explanation:
After a storm, water runoff from lawns, streets, and parking lots carries with it various chemicals and contaminants, including oils from vehicles. This runoff containing fertilizers can lead to water pollution when it reaches bodies of water. The fertilizers cause an excess of nutrients, which can result in algal blooms and decreased oxygen levels in the water, creating what are known as dead zones. Water pollution can originate from both point sources, such as sewage treatment plants, and nonpoint sources, such as residential areas where chemicals from lawns are carried into waterways.
Groundwater and surface water are both affected by run-off. Groundwater may become contaminated, though its natural cleaning process is slower compared to surface water, which is somewhat cleaned by sunlight, aeration, and microorganisms. To prevent runoff pollution, measures include reducing fertilizer use and preserving wetlands, which serve as natural filters.