What type of water does greywater refer to?

• A. Water from toilets
• B. Filtered groundwater
• C. Water from sinks and showers
• D. Rainwater runoff

Answer: (C)

Greywater refers specifically to the relatively clean wastewater generated from non-toilet plumbing fixtures. This includes water from sinks, showers, bathtubs, and washing machines. The primary reason greywater is significant in water-efficient landscaping is that it can be reused for irrigation and other non-potable purposes, thus conserving fresh water resources.

In contrast, water from toilets is categorized as blackwater and is typically not suitable for reuse without extensive treatment due to its higher contamination levels. Filtered groundwater pertains to naturally occurring water found underground, which is completely different from the reused water concept of greywater. Rainwater runoff is water derived from precipitation that flows over surfaces, which may or may not be collected for irrigation but is not classified as greywater.

Thus, identifying greywater correctly as water from sinks and showers is essential for applying sustainable landscape practices and promoting water conservation effectively.