What is the purpose of pre-filtration in rainwater harvesting?

• A. To prevent sediment, leaves, contaminants, and debris from entering the system
• B. To remove microorganisms
• C. To increase water temperature
• D. To add chemical oxidants

Answer: (A)

Pre-filtration in rainwater harvesting is about screening out larger solids before water enters storage or treatment components. This helps prevent sediment, leaves, and debris from entering the system, which reduces clogging, protects pumps and downstream filters, and lowers ongoing maintenance. It also helps improve overall system reliability by keeping solids out of the later treatment stages. It isn’t mainly for removing microorganisms (that comes from disinfection), it doesn’t aim to change water temperature, and it doesn’t involve adding chemical oxidants.