Greywater is just what it sounds like, something between white and black. With freshwater on one end of the spectrum, and blackwater on the other, greywater is waste water that results from washing laundry, showering/bathing and using the sink. While there are some soaps and other residues that build up in grey water (resulting in a grayish color, hence the name), this water is generally safe to use for irrigation of lawns, gardens and flower beds, or for flushing toilets (blackwater is what comes from toilets).

Did you know that greywater makes up something like 60% of the waste water produced by the United States? Can you see what a huge difference it could make to start recycling this greywater? Recycling greywater is a key issue when it comes to true sustainability.

Types of Water and the Problem with the Waste System in Many Areas

Freshwater is of course, fresh, clean water that has fallen in the form of rain or come from a water treatment facility, clean lake or well. The main thing that distinguishes between greywater and blackwater are the microorganism and pathogen content, nitrogen and decomposition time.

Basically, greywater becomes blackwater as soon as fecal matter or highly toxic substances enters into the picture. Blackwater has the potential for spreading disease, whereas greywater is perfectly safe to use for many household tasks and irrigation.

The problem is that in far too many areas, blackwater is allowed to mix with greywater. This contaminates perfectly usable greywater, rendering it completely unusable and dangerous. This also wastes resources in that the grey water now needs to be treated as heavily as the black water. What’s even worse though, is that by diluting the blackwater with all the greywater, this is allowing blackwater to contaminate underground water in some places. This old fashioned system has got to change. The need for separating greywater and blackwater is now clear.

Largely, this lack of efficiency is due to mindless repeating of historical practices. Though modern plumbing technology makes separating the two types of water quite easy, there just really isn’t a reason not to stop wasting perfectly viable greywater. It’s simply time to readdress the way the waste water is handled, in light of what we now know.

Ok, so how do we start safely recycling our greywater for use as irrigation water?

How about taking the small step of using bathroom sink water to flush the toilet? The Sloan Valve company came out with a system that fits under the sink. For something even simpler, check out Gaiam’s Toilet Lid Sink.

For a whole-house greywater reclamation system check out this very nice series: Home made DIY Grey water system wawter recycling.