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Matrix by Callison - 2.0 Water

2.1.2 Grey Water and Water Recycling

2.1 Water Reuse

Reduce potable water demand by deploying a system to collect and reuse greywater. The definition of greywater varies form one jurisdiction to another; it is defined here as wastewater generated from sinks, showers, laundry, dishwashers, or any other use except for toilets. Uses for greywater include irrigation and sewage conveyance.

Collected greywater is filtered, treated, stored and reused. Other system components include pumps and overflow drains that are connected to the sewer line.

Identify water uses in the building that can provide a supply of greywater. Target uses with high water demand, such as laundry and dish washing. Concurrently, specify low-flow plumbing appliances and fixtures to reduce water demand. Low flow fixtures can cut water demand by 25 to 50 percent compared to conventional fixtures. (Source: Greywater uses include irrigation and toilet flushing. Self-contained laundry water recycling systems are also available and can reduce potable water use by up to 80%. (

Separate conveyance infrastructure required for reclaimed water (“purple pipe”) increases the first cost or rainwater catchment systems. However, water savings of 50% or more help to offset that cost. In addition, costs associated with potable water supply and sewer infrastructure are projected to escalate with accelerated effect in developing countries.

Greywater use and water recycling reserve potable water for high-grade tasks and utilize lower-quality water for lower-grade tasks, thereby reducing the demand for potable water.

Greywater supply infrastructure is independent of and in addition to potable water supply infrastructure. Code requirements may limit the use of greywater for functions other than toilet flushing and sub-surface irrigation; greywater regulations vary widely from one jurisdiction to another. Greywater can not be used to irrigate edible plants. Space must be allocated for water treatment systems and storage.

1.4.9 Green Roofs
1.4.10 Green Walls
2.1.1 Rainwater Storage & Use,
2.2.1 Water Efficient Appliances
2.2.2 Xeriscaping
3.1.0 Waste Water Treatment
3.1.2 Living Machines
5.3.1 Code & Zoning Requirements