Harvested water for flushing

[Mary Fisher]

Has anyone installed a system for flushing the wc using harvested water?

We'd like to be able to switch between mains and pumped collected water. This would enable harvested water to be used for the garden in summer and not wasted in winter - when there is more rain to collect but it isn't used.

Spouse has made plans to do it but I wondered if anyone here had done it and could give the benefits of experience.

Theories and opinions are inappropriate although *authoritative* legal advice will be welcome. We're confident that we know what's necessary but there might be something which we hadn't thought of and a qualified plumber could advise.

TIA

Mary

[Dave Plowman (News)]

My thoughts would be to provide a separate storage tank in the loft which only feeds the toilets, and arrange for that to be filled - via a pump - from your collected water, or from the mains when non is available. However, with the current cost of water, it would take some time to recoup the investment.

[Bookworm]

You will have to be careful not to risk contaminating the potable water supply. There are water regulations that cover what you can & cannot do in this area.

Look on the website:

is the Water Regulations Advisory Service. There are links to the actual regs from there. Before the flamers start up about regulations, red tape etc etc. It is in everyones best interest that potable water supply is strictly regulated.

[Lobster]

Wouldn't there be a likelihood that contamination in the harvested water

- ie assorted bits of crud which it would undoubtedly contain - would damage/clog up valves, prevent float valves from seating properly?

David

[Dave Liquorice]

Assuming ther orginal source of water is the roof, yes it will contain "bits" but most will settle out in the primary collection tank. The fill rate of conventional 3 to 4' high, diverter fed, top filled water butt isn't enough to disturb the sediment. Take the pump feed 6" above the bottom and through a coarse filter so as not "suck up" the sediment(*) and I think very little will find it's way to the loft tank. Up in the loft tank it can settle again with the outlet a little above the base.

Finding a pump that doesn't have to high a flow rate, thus stiring either the lower or upper tank might be fun. Also automatic (if required) change over between mains and harvested water might be fun and you really do not want any back siphonage of harvested water into the mains...

(*) Perhaps arrange the feed through a short upstand of pipe with filter element on the sides rather than the end.

[Bookworm]

. Also automatic (if required) change

How bloody irresponsible an answer.

It doesnt sound like 'fun' to me. I take very seriously any threat to Public Water Supplies. Your local Water Inspector might have something to say about the possibility of a criminal offence, which it could be.

[meow2222]

This is all a done deal in the sense that its been done and people know how to do it effectively, legally and safely. However I havent done it personally, so I'll do as Mary said and not tell her.

NT

[Bob Minchin]

A friend of mine is currently selfbuildng a house and has installed a collection tank under the patio with an access hole for cleaning etc. It is filled from the gutters and has a commercial controller to switch between mains and tank water. He plans to use it for loo flushing and the washing machine.This extra potential use for filtered rain water should significantly shorten the payback time. Not sure if he is using it for the dishwasher too but the cost of electical heating might make this less economic?

Bob

[Andy Hall]

Not really because most dishwashers are now cold fill using small amounts of water.

However, I am not sure that it's a good idea to use untreated water for washing dishes

[Huge]

Tell me, have you been a humourless pedantic f****it all your life or have you come to it recently?

[Ash]

No-one but a cretin would even think of it!

Your wife and my wife must be totally different personalities to even countenance washing clothes with less than crystal clear water, which yours from the tank isn't likely to be.

[Mary Fisher]

Yes, we plan to do that.

Saving money is not the aim. We already have a reclaimed tank anyway and plenty of plumbing stuff.

Pay-back isn't considered when we buy a bottle of wine so why should it for this?

Mary

[Mary Fisher]

A filter has to be part of the system.

Mary

[Mary Fisher]

We intend manual switching.

That's what we plan.

Mary

[Andrew Gabriel]

It is from my water butt.

[Mary Fisher]

That would be ideal but retro fitting would be too great an upheavel.

Yes, that's what we've been considering too.

It's not legal either, as far as I can discover.

Mary

[Mary Fisher]

It's perfectly acceptable and even recommended.

[Mary Fisher]

We know that.

I agree.

Mary

>

[Dave Liquorice]

Except that dishwashers wash a pretty hot temperatures, hot enough to kill of most bugs and if the heat doesn't get 'em the dishwashing chemicals probably will. B-)

Quite, all manner of interesting and visible wildlife in our, covered, water butt. Loo flushing yes. Washing clothes and dishes? Not for me thank you. Despite what I say above. B-)

[Dave Liquorice]

What the f*ck are you on, 'cause it's shit.

I said "you really do not want any back siphonage". It is warning that without careful thought back siphonage is a non-obvious possibilty which "you really do not want".

"Fun" as in a challanging techincal problem, something that you obviously have no imagination to comprehend. Actually the isolation is piss easy to do, it's the control system that's the hard bit.