Saving Graywater

[Charles Bussher]

For many years I’ve been toying with the idea of doing something more useful with the thousands of gallons per month of graywater (that’s the stuff that drains from my sinks, lavs, and baths) that normally goes into my municipal sewer system. I’ve finally decided to do something. I’ve got a backyard with fruit trees and vegetable garden, front and side yards with ornamental plantings, and for years I’ve been watering them with potable municipal water from the various hose bibs I’ve installed at all four sides of my home. It’s always irked me that I use so much good (and increasingly expensive) water for this plant irrigation.

I’ve installed diverter fittings with valves on the 2″ DVW lines that drain my bathtub/showers and kitchen sinks so that when I use these fixtures the water drains into my backyard and front/side plantings. Since I’ve got a full basement under my house, it was relatively easy to run the pipes. The valves allow me to go downstairs and divert the water to the irrigation system or route it into the sewer when I want to. I think this system will save money, but I’ll have to use it for a while to see just how much.

I didn’t bother going to my local inspection office to see if they would authorize this “experiment.” I’m pretty sure they would have been puzzled and not helpful.

Have any of you thought about doing this sort of thing? I’ve always been a conservative when it comes to plumbing, but now I feel like a radical plumbing anarchist.

NtP

[Retired plbg1Participant]

Nick I toyed with the same idea, but if you tell your Plbg. Insp. he is going to tell you know, but I think you will get a smell from that later on, but try it and see how it works.

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Art retired plbg

[DUNBARParticipant]

I don’t deal with gray water systems like I used to years ago.

What is odd is I have seen new subdivisions, in rural areas where one side of the street the gray water was allowed separate, the other not.

I am all for conserving water; even though the majority of the new 1.6 toilets came out being prototypes and very troublesome, humans defecate 1 time to 4 times urinating in a normal given day on average. If you do the math on the reduction of water that would be wasted if 3.5 gallon flush toilets were still being produced, that is astounding.

The consideration of your idea would be the chemicals; dishwasher detergent, laundry detergent, bath oils, and regular soap.

I don’t know what the reactive result would be on the surface of the ground and what the trees, and shrubs will do, but I would say John (Septic Tank Yank) has this knowledge right down the alley.

If I was in your shoes, I would try it also, just make sure that no one cleans out paint brushes or puts harsh chemicals down the drain for whatever reason.

If the water is going to be used above ground, the possibility of chemical residue transfer is likely by humans and animals alike. The smell can be generated from food matter which will attract animals. Vegetation matter can be acidic, like tomatoes and other vegetables that will create this when mixed with other waste water from the kitchen sink. Grease is another, pasta noodles that always manage down the drain.

Let us know what results from your idea.

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“Your best interest is secured by making the right decisions the first time.”

[nicktheplumberParticipant]

RP & Dunbar,

Thanks for the replies. Yeah, I know exactly what the Inspector would say. Not allowed. I’m going ahead with the experiment anyhow, because I think it’s a good idea and good for the environment. I know I could be wrong, and if I am, all I’ve got to do is disconnect the two 2″ diverters I’ve installed and everything is back to the status quo.

I’ve thought about the soap and sanitary issues. I use only biodegradable detergents for dish and clotheswashing. These and any organic solutes that come from the drains are essentially low grade fertilizers and no worse and probably a lot better for the environment than the commercial stuff I’d been putting on my lawn, trees, and garden. As regards the kitchen sink drainage, I use strainers and no garbage disposals and don’t let any macroscopic solids down the drains. And of course I’m not diverting toilet waste, just the graywater.

[Robert Stephen MortonParticipant]

Nick. I went to a seminar a few years ago & was shown that up to ninety percent of people urinate in the shower, all wash themselves, some wash their backsise, blow their noses, women wash themselves when menstruating. SHOWER water was as black as septic if held in a container for one hour.
Laundry water was the same for the same reasons of underpants, hankies etc.
Basin water because of the blood in the water after cleaning teath. which left kitchen waste.
Bob
However One can go to a Piggery & purchase a ton of fertiliser & spread the fertiliser without any regulatory problems.
Bob

[PLUMBILLParticipant]

All the approved gray water systems I have seen look like a mini septic system, no surface water discharge permited. With surface water discharge form from the various fixtures maybe you should put those little flags around your yard that fertelizes are being added so kids next door don’t run through your yard in bare feet and the pets don’t drink from any pools of standing water.

The money you will save will only be on water usage you will still have to pay for sewer chages because those are based on what your house meter reads for water going through it.

[Author]

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