How are freshwater resources cleaned?

Freshwater resources are cleaned through various methods, including filtration, chemical treatment, and biological processes. Filtration removes physical impurities, while chemical treatments, such as chlorination or ozone treatment, eliminate pathogens and contaminants. Additionally, biological processes, like constructed wetlands or biofiltration, utilize natural organisms to break down pollutants. These methods can be employed individually or in combination to ensure safe and clean freshwater for consumption and use.