Collecting grey water in a butt?
Discussion
Can somebody please tell me whether what I'm contemplating is daft, before I go ahead and do it?
I'm considering buying a second water butt and re-routing the bathroom grey water soil pipe into it, with an overflow pipe coming from near the top of the butt either going back into the soil stack, or perhaps into a guttering down-pipe. The grey water would be used for watering the garden, etc.
Can anybody suggest any problems with this idea, or any reasons why I shouldn't do it?
I'm considering buying a second water butt and re-routing the bathroom grey water soil pipe into it, with an overflow pipe coming from near the top of the butt either going back into the soil stack, or perhaps into a guttering down-pipe. The grey water would be used for watering the garden, etc.
Can anybody suggest any problems with this idea, or any reasons why I shouldn't do it?
Hmmm... Yes, I guess the phosphates will feed bacteria and algae.
I have seen valves on the market that allow you to control whether the grey water goes into your butt (!) or into the drain. I hadn't seen the point of that until now; I suppose the idea is that you switch the valve the day before you plan to do some watering in the garden and collect next morning's bath water for use the same day.
Perhaps what I should do is combine both of these approaches: have a valve that allows me to send the grey water to the drain when it's not required, and also have an overflow pipe from the butt to the drain for when I inevitably leave it in the wrong position.
I have seen valves on the market that allow you to control whether the grey water goes into your butt (!) or into the drain. I hadn't seen the point of that until now; I suppose the idea is that you switch the valve the day before you plan to do some watering in the garden and collect next morning's bath water for use the same day.
Perhaps what I should do is combine both of these approaches: have a valve that allows me to send the grey water to the drain when it's not required, and also have an overflow pipe from the butt to the drain for when I inevitably leave it in the wrong position.
I am old enough to remember several gardening programs broadcast in 1976 when the drought was big news.
Gardeners World did a series of experiments on Tomato Plants, Lettuce and the like to see if washing up water/shower water/bathwater etc could be used on the garden.
Broadly they found that it all could be used successfully without problems.
EXCEPT
When Chlorine Bleach, Hydrogen Peroxide, Ammonia or similar concentrated chemicals were used in washing clothes or cleaning.
This was really pretty clear from the quite extensive tests.
You will be OK with shower water, bath water etc but I would exercise serious caution if strong cleaning products containing Peroxide or Chlorine or Ammonia are used.
Hair dyes for women are the most likely culprits and laundry procucts could be a real problem.
But it did work for 90% of the grey water they used. Just be careful with the chemicals you are introducing.
Gardeners World did a series of experiments on Tomato Plants, Lettuce and the like to see if washing up water/shower water/bathwater etc could be used on the garden.
Broadly they found that it all could be used successfully without problems.
EXCEPT
When Chlorine Bleach, Hydrogen Peroxide, Ammonia or similar concentrated chemicals were used in washing clothes or cleaning.
This was really pretty clear from the quite extensive tests.
You will be OK with shower water, bath water etc but I would exercise serious caution if strong cleaning products containing Peroxide or Chlorine or Ammonia are used.
Hair dyes for women are the most likely culprits and laundry procucts could be a real problem.
But it did work for 90% of the grey water they used. Just be careful with the chemicals you are introducing.
Simpo Two said:
I seem to recall a story about man who, because of a drought/hosepipe ban, thought he'd save water by draining his bath water out of the window onto the garden.
He used a hose to drain the bathwater - and was prosecuted for using a hose during a hoepipe ban...
Only in England eh?
My old man had a visit from the council for exactly this. Somebody had reported him using a hosepipe in his garden so the council come round to have a word. My dad demonstrated that he was using grey water but the council said it didn't matter as how did they know he wasn't running the bath just to fill the tank up (which he wasn't). He wasn't fined or anything, but was told he should stop doing it.He used a hose to drain the bathwater - and was prosecuted for using a hose during a hoepipe ban...
Only in England eh?
Well, I've now ordered oner of these grey-water diverter valves, which allows you to control whether the water goes into the drain or the butt.
Also, I've had an attack of the bleedin' obvious and realised that the best way of having an overflow coming out of the butt is to fit a rainwater diverter to a nearby gutter down-pipe, which will provide the dual function of collecting rainwater as well as providing an overflow path for excess grey water.
I'll try controlling smells by using one of the various water butt treatment additives you can get, which claim to keep the water from going bad.
I've also bought a water butt pump, so I can water the garden using a hosepipe.
The rules from my local water company (Veolia Central) are here. I intend to print the first two pages and laminate them, so that I can show them to any busybody passer-by who sees me using a hosepipe. The bottom of page two says:
Customers may water their gardens:
- By hand, using a bucket or watering can.
- With greywater through a hosepipe.
- Using rainwater from a water butt by hand or through a hosepipe.
Also, I've had an attack of the bleedin' obvious and realised that the best way of having an overflow coming out of the butt is to fit a rainwater diverter to a nearby gutter down-pipe, which will provide the dual function of collecting rainwater as well as providing an overflow path for excess grey water.
I'll try controlling smells by using one of the various water butt treatment additives you can get, which claim to keep the water from going bad.
I've also bought a water butt pump, so I can water the garden using a hosepipe.
The rules from my local water company (Veolia Central) are here. I intend to print the first two pages and laminate them, so that I can show them to any busybody passer-by who sees me using a hosepipe. The bottom of page two says:
Customers may water their gardens:
- By hand, using a bucket or watering can.
- With greywater through a hosepipe.
- Using rainwater from a water butt by hand or through a hosepipe.
I've now turned my plan into reality. It isn't pretty, and makes the side of the house look like Woking's answer to the Pompidou Centre, but it's "wheelie bin alley" anyway so doesn't really matter.
The valve is nicely made, although I thought the outlet hole for water going to the butt looked rather narrow - probably only about 10mm or so. Initially I installed it in the horizontal section of waste pipe shortly after it exits the wall, about 3m up. Unfortunately it caused water to back up into the shower tray when diverted to the butt, although it was fine when the valve was set to the drain.
Thinking that it was the narrow hole causing a constriction, I decided to re-plumb it so that there's a vertical drop with the valve at the bottom. I figured this might create enough head pressure to push water through the hole a bit faster. I rigged it up "dry" and tested it, and it seemed to do the trick.
Unfortunately, after I'd done all the solvent welds up and siliconed the connections to the valve and waited for everything to cure, the next morning we had the same problem of water backing up into the shower tray.
The experienced plumbers amongst you are already tutting and telling this numpty what he'd done wrong, but it took me a bit of thought before I realised the problem: everything is too airtight! There is, after all, a good reason why the soil stack is vented at the top. The valve is so nicely made that it doesn't allow any air movement when the drain is closed off. So I've now drilled a 5mm breather hole in the top of the horizontal pipe just before the vertical drop, and I believe the problem really is cured now - the water flows freely out of the shower tray just like it used to.
I am really shocked at how much water our shower uses! It's not a power shower, but it is mains pressure (running off a combi boiler). After my wife and I have both had our showers in the morning, the 250-litre butt is about half full! Now I understand why the two of us consume a colossal 400 litres of water per day.
The pump I've bought (the Hozelock one) works well, and with a full butt I get at least 30 minutes of hosepipe time, possibly more. It's enough to water a substantial amount of our garden. The good thing is that we'll fill the butt in only two days, which means we won't have to store the water for long before we've got a usable amount. Ironically, I think we might end up watering our garden more generously this year! So far it doesn't smell, but it's early days yet.
The valve is nicely made, although I thought the outlet hole for water going to the butt looked rather narrow - probably only about 10mm or so. Initially I installed it in the horizontal section of waste pipe shortly after it exits the wall, about 3m up. Unfortunately it caused water to back up into the shower tray when diverted to the butt, although it was fine when the valve was set to the drain.
Thinking that it was the narrow hole causing a constriction, I decided to re-plumb it so that there's a vertical drop with the valve at the bottom. I figured this might create enough head pressure to push water through the hole a bit faster. I rigged it up "dry" and tested it, and it seemed to do the trick.
Unfortunately, after I'd done all the solvent welds up and siliconed the connections to the valve and waited for everything to cure, the next morning we had the same problem of water backing up into the shower tray.
The experienced plumbers amongst you are already tutting and telling this numpty what he'd done wrong, but it took me a bit of thought before I realised the problem: everything is too airtight! There is, after all, a good reason why the soil stack is vented at the top. The valve is so nicely made that it doesn't allow any air movement when the drain is closed off. So I've now drilled a 5mm breather hole in the top of the horizontal pipe just before the vertical drop, and I believe the problem really is cured now - the water flows freely out of the shower tray just like it used to.
I am really shocked at how much water our shower uses! It's not a power shower, but it is mains pressure (running off a combi boiler). After my wife and I have both had our showers in the morning, the 250-litre butt is about half full! Now I understand why the two of us consume a colossal 400 litres of water per day.
The pump I've bought (the Hozelock one) works well, and with a full butt I get at least 30 minutes of hosepipe time, possibly more. It's enough to water a substantial amount of our garden. The good thing is that we'll fill the butt in only two days, which means we won't have to store the water for long before we've got a usable amount. Ironically, I think we might end up watering our garden more generously this year! So far it doesn't smell, but it's early days yet.
Looks a good set up and am considering something similar myself. With my tree hugging hippy hat on where does the overflow via the drainpipe go to? Roofwater is essentially clean and is fine to go to surface water eg a ditch or a soakaway. However grey water going into a ditch or pond could cause an algal bloom / odour issues. If it goes to a soakaway it should be ok but ideally it would go to the soil pipe / foul sewer...just something to consider if the jobsworth from the council were to come round.
Good solution but a bit surprised that you got the airlock or that there wasn't any info in the destructions warning you about it. Shame you've had to modify it, I'd have thought the manufactureur should advise you of this?
But you're right it does all look a bit of a shambles. Nothing a coat of paint matching the wall colour woul;dn;t cure though.
But you're right it does all look a bit of a shambles. Nothing a coat of paint matching the wall colour woul;dn;t cure though.
twosocks said:
if the jobsworth from the council were to come round.
Tell them the green butt is actually a mash tun and you're making illicit whisky in a system cunningly disguised as a waste-water collection system.When the police come round, you open the butt and say 'What whisky? Look, it's a water butt! Bloke at the Council must have made a mistake!'
At the moment, the water butt overflows via a rainwater diverter kit (on the other side, so you can't see it in the picture). This goes into a gutter downpipe that empties into a small open drain into the sewer. I haven't yet filled the butt to see whether that overflow can cope with the shower flow. I figured it might not, so I plumbed a tee piece into the bottom of the waste pipe going into the soil stack so that I can make a proper overflow into there if necessary. This is all very experimental! 
The instructions with the valve didn't suggest that ventilation would be a problem, which is a pity because it was an easy issue to solve once I'd figured out what was happening. Some people might have given up. I might email them about that, although I get the impression the product is made as a hobby by a couple who are about to retire - their website says the moulds are up for sale, so I doubt they'd be interested in changing their instructions now.
You're right - a lick of paint might be in order!
LOL @ Simpo Two!
The instructions with the valve didn't suggest that ventilation would be a problem, which is a pity because it was an easy issue to solve once I'd figured out what was happening. Some people might have given up. I might email them about that, although I get the impression the product is made as a hobby by a couple who are about to retire - their website says the moulds are up for sale, so I doubt they'd be interested in changing their instructions now.
You're right - a lick of paint might be in order!
LOL @ Simpo Two!
Edited by Dr Mike Oxgreen on Tuesday 27th March 10:28
I wonder if the 'greyer' part of the water, (eg shampoo/soap) will settle at the bottom or float to the top. If it's the later than ensuring an overflow sounds like quite a good idea to me!
You've given me some ideas, such that I've been trying to find out if the bath products we're using on my baby (contains light liquid parafin due to skin conditions) is safe for plants. I face the difficulty of having a downstairs bathroom so plumbing into the outlet like you have isn't as easy for me...
You've given me some ideas, such that I've been trying to find out if the bath products we're using on my baby (contains light liquid parafin due to skin conditions) is safe for plants. I face the difficulty of having a downstairs bathroom so plumbing into the outlet like you have isn't as easy for me...
Gassing Station | Homes, Gardens and DIY | Top of Page | What's New | My Stuff