Grey Water Systems?

Can some please explain in detail what is inside a grey water system and how they work. Can you please also keep it as simple as possible. Thanks

There are so many different systems you can setup. The easiest is a hose or even easier are buckets brought out.

Greywater systems take used water from sinks (other than the kitchen sink - which is "dark grey water"), showers, tubs and washing machines and return it to the landscape. They do this in any number of ways.

Starting with the simplest (and generalizing greatly!):
--you can unhook the p-trap below a sink and place a bucket under this to collect greywater. You can then take that water outside and water your woody stemmed plants with it (trees, shrubs) - don't water herbaceous plants with this method. This is the so-called "bucket method". A variation of this is to do your dishes in tubs in the sink and then take the tubs outside....
--you can do a bit of plumbing to get your greywater out of the house. This works for sinks and sometimes tubs/showers depending on where they're located in the house. Essentially you replumb with a jandy valve so that you can switch between sewer and landscape. You need a drop of 1" to every 10 linear ft the pipe travels to get to it's ultimate destination. The destination should be some kind of mulched pit/basin and ideally, the greywater should vent UNDER the mulch.



--If you live in a climate that lends itself to having an outdoor shower part or all of the year, simply set up a hose over a tree limb and maybe make a little platform to stand on and put a curtain around the whole thing (or not - depending on your personal taste!) Or you can build something more permanent like I did. See pic below showing the beginning setup of my outdoor shower - three drains venting into three infiltration basins. The full blog post documenting this project is here: http://abundantdesert.com/2013/11/02/dolce-verde-outdoor-shower-part-1-design/



--Washing machines have pumps in them so that water is pressurized and can travel quite a distance, usually 80-100 ft, so it does not have the limitations of being gravity fed. You can set up a simple system whereby the water is diverted into a 55 gal. barrel (because it's pressurized water, this is done to stop the water from scouring the soil if it was piped directly to the landscape) and then hook up a hose to the barrel and direct the hose to the WOODY plants you want to water. OR you can attach drip irrigation to this setup (because it's pressurized). Below is a project that Watershed Management Group did at my house in Nov 2013 doing exactly this (irrigation) - it's called "Laundry to Landscape" or L2L for short.



--If you want to actually purify greywater before reusing it - you'll need to pass it through some biological systems, or multiple systems depending on how "clean" you want it. This involves things like sand, gravel or mulch filters, reed beds...all the way up to "living machines" (google John Todd Living Machines).

To define a greywater project:
--determine the water source
--what do you want to use the water for? Is it a good candidate for greywater use? (in other words - will it be used for woody plants - NOT herbaceous food plants) How far away is it from the water source?
--is the water source on an exterior or interior wall? If not on an exterior wall, can you move it so it is? Or even move it outside? (I moved my washer to my back porch and my main shower is in the backyard).
--is the greywater pressurized or not?
--what's your budget? There are some FANCY systems out there...

A really useful online source of information is Brad Lancaster's site - he is the author of "Rainwater Harvesting for Drylands and Beyond, Vol 1-2": http://www.harvestingrainwater.com/greywater-harvesting/

Thanks Jennifer! I am in the UK so the water would not be used to water plants as the rain does that enough, it would be more for flushing toilets. What you said about purifying and cleasing it really interested me. What would needed to be included to clean the water enough to flush toilets and how would we get it to work?

Many Thanks

James

Thanks for clarifying, James! (and welcome to Permies)

For that kind of setup - turn off the water to your toilet. Then remove the trap under your bathroom sink and put a bucket under it. When you need to flush, simply remove the bucket and pour the water into the tank, then flush. Because the greywater is not stored (never store greywater - it gets stinky!), there is no need to cleanse it further.

There are some fancy ways to hook up this plumbing so that it works automatically. Here are a couple of pics - from uber luxurious to a DIY hack!



Liked this one from: http://www.instructables.com/id/Hack-a-Toilet-for-free-water./

Thank you. I'm affraid that the water I'm using will need to be stored and therefore cleansed. Sorry to be such a pain but how would I do this?

Just so I can get a handle on what you actually want to do....

--where are you getting the greywater?
--what is the volume?
--for what purpose are you wanting to store it?

Personally - I would NOT store greywater - it's not a 'best practice'. Methods of cleaning greywater for storage/reuse often involve biological or living machine systems - definitely more complex.

I'll agree with Jennifer that you shouldn't really store 'grey water', but there is no limit to how long you can keep your 'compost tea' bubbling. And what is the difference between grey water and compost tea? Time and the maturation of some aerobic bacteria. Grey water is anaerobic, and as long as it sits in a tank with no air exchange, it's going to get more fetid and smelly as the anaerobes have a field day. No, if you don't have a place to put it right away, keep it in a tank, but bubble air through it. That converts it in short order to aerobic compost tea, which as long as it has a source of food and air, can sit there stewing away until you are ready to use it to water some plants. In fact, the longer you keep compost tea stewing away, the more dominated by fungal microorganisms it becomes. Float some leaf litter in it and let it sit for a couple weeks, and it's really a sea of bubbling hyphae ready to colonize some soil.

John - excellent points! Never quite thought of it that way.

We'll have to wait to hear back - but I get the impression that the water was to be reused in toilets, not the landscape.

The Oasis website has a lot of information about grey water. oasisdesign.net
Especially: http://www.oasisdesign.net/greywater/misinfo/index.htm
I bought their book too and love it.

First and foremost decide WHY you want a grey water system. Is it because you need to water your landscape? (In your case, no). Or do you just want to do something green and conserve a resource, but in fact don't have a water shortage? In which case you should stop and look elsewhere first for more appropriate and effective ways to conserve resources.

Art Ludwig on the link above about common greywater errors says:
Error: Automated reuse systems for flushing low usage (e.g., residential) toilets

Automated systems for flushing toilets with grey water are complex and expensive. Flushing with untreated grey water will result in fouling of the tank and fetid anaerobic smells (see "Error: storage of grey water"). Treatment is fabulously expensive. The cost for a typical system touted on the web is $10,000. Even at the punitive water rate of $0.01 a gallon, that's 5 years of 325 flushes a day to recoup your investment, not counting lost interest, electricity, or system maintenance. The $650 Homestead Utilities system (s16), which is the cheapest I’ve heard of, would take 23 flushes a day—if you had a restaurant it could earn its keep.
Extreme economic unfeasibility can indicate extreme ecological unfeasibility; the earth could be way better off if you just wasted the water than if you wasted all the plumbing, pumps, tanks, filters, and electricity needed to make this sort of system work.

Preferred practice
First, put in a low flush toilet (or a waterless composting toilet—see inside back cover). Then, "if it's yellow let it mellow, if it's brown flush it down." Third, toilets can be flushed with grey water by simply bucketing it from the bathtub/shower directly into the toilet bowl (not the tank, where it will fester). An added plus of reusing bathtub water in this way is that due to flush volume always being under direct intelligent control it is always less. Also, in cold climates you get a primitive but highly effective sort of grey water heat recovery as the bath water sits there and cools.
Once again, the Mexican housewife's system soundly outperforms the US engineer's system! If none of these preferred options appeal to you, you're probably better off just forgetting about flushing your toilets with grey water.

Exceptions
Every toilet should have a lid that routes clean drinking water en route to bowl-scouring flush through a basin where it can be used for washing hands.

Multifamily, institutional or any other high use installations can benefit from flushing toilets with highly treated grey water, especially when incorporated in the original design of the building. If you have highly treated water already and don’t know what to do with it, say from a constructed wetland, it may be worth supplying it to the toilet. An important advantage is that toilets need flushing every day, whereas irrigation need is usually seasonal.
"Clearwater” such as air-conditioner drip, reverse-osmosis water purifier reject water, and fixture warm up water is a natural for flushing toilets. It needs no treatment and can store indefinitely. Steven Coles of Phoenix, Arizona suggests that if you have an evaporative cooler, supply the toilet from its reservoir and you’ll keep the mineral concentration in the cooler water from rising.

Jennifer Wadsworth wrote:Just so I can get a handle on what you actually want to do....

--where are you getting the greywater?
--what is the volume?
--for what purpose are you wanting to store it?

Personally - I would NOT store greywater - it's not a 'best practice'. Methods of cleaning greywater for storage/reuse often involve biological or living machine systems - definitely more complex.

It's going to be stored mainly because in the location there will be taps on their own (some of them anyway) so it would be better if all the water is in a ass collection area and can then be put back into the system to be used to flush the toilets. There is quite a lot of water but I'm not exactly sure on the volume.

Many Thanks

James

For something like that, it's going to get expensive, FAST.

Check out these systems below.

Jennifer Wadsworth wrote:Liked this one from:  http://www.instructables.com/id/Hack-a-Toilet-for-free-water./

We also saw that same idea and made our own, too!

I second the recommendation for the Oasis website. It's a very comprehensive look at the topic. I will share some of my choices and thoughts on greywater systems.

I originally researched this topic because it was not possible for me to tie in to septic or sewer. I had to figure out a way of safely and effectively disposing of my greywater. So, my method is not the most effective if you have other goals in mind, such as dispersing the greywater across your entire landscape for irrigation.

I read about and considered adopting multiple greywater systems. The "Green Monster" design, where you have the greywater exit the home and enter a large container with filtering materials, as well as water loving plants, before the water leaves the container ostensibly filtered seemed interesting, but fairly intensive to construct and maintain. Plus, I wanted to use this system for all my greywater, and even when trying to conserve water, the average adult uses quite a bit in a day.

I counted out any system involving pumps, holding tanks, or other larger, more mechanically complex infrastructure. I wanted something simple and low maintenance.

In the end, I settled for a mulch-basin system adapted roughly from the diagram on this webpage: http://oasisdesign.net/greywater/brancheddrain/ But! I did not want to use a branched drain system, where the flow of greywater gets split multiple times by different pipes, as it seemed this could become clogged much more easily (which would be a nightmare to locate and fix) and required far more time/energy to construct and maintain. Instead, I opted for one large mulch basin.

In the time I've had a mulch basin of this variety, it has required little to no maintenance. The basin is dug into a natural, gradual slope, and is about 70 sq. ft. with three Inkberry bushes planted within. A pipe runs underground from the greywater outlet on the house, down the slope, and into an upside down 5-gallon bucket with holes drilled in the sides. This bucket has been buried within the mulch, and a concrete block acts as the access lid. As an overflow mechanism, there is another pipe running from the top-most ring of holes in the bucket, through the mulch, and down the slope into the furthest area of the basin. When designing a single basin this large, it's helpful to have ways to distribute the water throughout the entire basin, rather than all of it pooling in the source.

People will say you need to put a screen on your greywater outlet, but this was a massive headache for me. Regardless of the thickness of the screen, there would always be sludge buildup and the water flow would back-up. Cleaning that is as bad as it sounds. Ultimately, I just removed the screen. I have drain screens inside the house on all my sinks and showers, as well as wet traps, so there is a barrier of water and a physical barrier for anything that wants to run up the pipe. Since the bucket is underground and buried, it is fairly inaccessible (though by no means impregnable) to anything larger than insects, and since there is only one pipe being used, frequent use of water keeps the pipe flushed out. I've had little to no issues with anything coming up the pipe. That said, mileage may vary based on your climate and fauna.

After figuring all this out, the only thing I now do to maintain the system is to check the outlet in the bucket every few weeks to a month, and if a layer of sludge has formed on the bottom to a degree that water cannot drain through the mulch and into the soil, I poke holes in the sludge wit ha stick and move it around so water can drain.

A basin like this will be a hotbed of life. Slugs, insects of all kinds, and various plants (in my case, clover) will proliferate around the outlet, which I see as a good thing. But don't be alarmed the first time you open your access cover in the spring and see a ton of activity. I once saw what must have been a hatching of drain flies.

As a next step, I plan to inoculate the basin with Winecap mushrooms this spring.

In a year or so, I may need to replace some of the mulch if it has broken down into more compacted soil.

The only other thing I would say is, be sure to use all biodegradable soaps, detergents, etc.!