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What is a Greywater System?

What is a Greywater System?

The term greywater refers to water previously used in a variety of applications, from bathing to hand washing and food preparation. The one exception is fecal matter, which means used water from toilets and from washing cloth diapers - called blackwater or toilet wastewater - is excluded from the definition of greywater. While greywater is no longer fit for some uses, like consumption or food preparation, it has a variety of other applications outside of those involving human consumption where it's functionally identical to freshwater. An apparatus that utilizes, cleanses and distributes greywater is called a greywater system.

The uses of greywater

Greywater Action, an organization that supports increasing the use of greywater to reduce freshwater consumption, provided an important clarification about this liquid: While it can appear dirty or clouded, it has a number of effective applications. One of the most common is irrigation, where many of the impurities present in greywater can provide a benefit in terms of fertilizing plants. One important point to consider is the potential harm that can be caused by greywater - because it can contain pathogens - limits how it's applied to plants. It's recommended to avoid application above the surface, especially by spray bottles. An underground drip system is frequently used instead. As long as greywater is repurposed relatively soon after its first use and doesn't come into direct contact with people, it's a valuable resource.

Grey water can also be used to replace the water used to flush toilets, and has a similar application with washing machines. Using greywater in these ways is environmentally friendly and, with the right system in place, can be more economical than frequent use of freshwater. We found the use of greywater can reduce freshwater needs by between 16 and 40 percent, and additional benefits are available. For example, using a greywater system reduces the stress placed on septic and sewage systems, which means they last longer - a benefit for individual homes and the larger community as well.

Residential greywater systems

Greywater systems inside homes are a new concept, but one that's growing in popularity. These systems capture water used in appropriate applications and provide short-term storage before it's utilized for washing clothes or flushing a toilet. A greywater system can be a professionally designed and installed, and there are also designs homeowners can craft and implement themselves.

Water Damage from Grey Water

Not all greywater can be reused or repurposed. For example, water that enters your home from a flood but does not contain sewage is also referred to as greywater by companies like Roto-Rooter that are in the water damage cleanup / water damage restoration business. Flood by greywater can be caused by a  weather event, an overflowing plumbing fixture or appliance or even a broken pipe. This type of greywater can saturate carpeting, furniture and drywall. It must be pumped out of a room or extracted using vacuum systems before drying equipment is put in place in the course of a water damage cleanup job.