Can a greywater system increase landscape sustainability?

Greywater System Design

A well-designed greywater system can significantly reduce landscape water consumption. In a typical system, wastewater is collected from sinks, showers, and washing machines and distributed through a branched drain system to irrigation zones. For example, a 2,000-square-foot home with a branched drain system can distribute greywater to 8-10 irrigation zones, covering up to 80% of the landscape area. Proper system design requires consideration of system pressure, pipe sizing, and water quality to prevent clogging and contamination.

Water Quality Considerations

Water quality is a crucial aspect of greywater system design. Greywater can contain high levels of soap, detergent, and other contaminants that can harm plants and microorganisms in the soil. To mitigate these risks, greywater systems often incorporate treatment components, such as sedimentation tanks, filtration systems, or UV disinfection units. In addition, greywater should be used for plants that are tolerant of high nutrient levels, such as succulents and grasses.

Benefits and Savings

Implementing a greywater system can result in significant water savings and cost reductions. According to the US Environmental Protection Agency (EPA), greywater reuse can reduce potable water consumption by 20-50%. This reduction in water consumption can lead to substantial cost savings, especially in areas with high water rates. Furthermore, greywater systems can also reduce wastewater disposal costs and alleviate pressure on municipal water treatment facilities.