Grey water

[undyingking]

Has anyone got experience of, or knowledge about, collecting grey water for garden use?

My current plan is to attach a water butt to the external downpipe from our shower, like the one that collects rainwater on the guttering downpipe. What do I need to consider?

For example, does gribble collect in the butt, that might need clearing out or treatment? What's the pH of the collected water going to be like? Do you need to let it stand before using it on the garden? And other such things that I haven't thought of.

Comments

[karohemd.livejournal.com]

I personally wouldn't do this without some sort of filtering system as I don't think soap and tensides are good for plants (or the groundwater).

[undyingking.livejournal.com]

Tensides ?

Same thing as surfactants I guess? I don't know much about this area of chemistry...

[karohemd.livejournal.com]

Er, yes, indeed, sorry. Didn't realise it wasn't the same usage in English. In fact, "tenside" doesn't seem to be used but wikipedia redirects you to surfactant when you enter tenside.
Made sense, though, tenside is related to tension so I didn't even think it would be different. I do know surfactant, though but my brain didn't get that far. ;o)

[chrisvenus]

Yeah... I was wondering about soap on plants being a good idea...

[undyingking.livejournal.com]

Spraying dilute washing-up liquid on plants is the standard way of keeping down greenfly. But we use Ecover for that... I don't know if my shampoo etc is bio-safe like that.

[bateleur.livejournal.com]

Although in fact detergents are harmful to all insects since they cause dehydration by stripping their waterproofing. (At least that's my understanding of how it works, but IANAE^[1].)

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[1] Where 'E' = Entomologist.

[undyingking.livejournal.com]

That's my understanding too. The theory is, I think, that aphids will be the only things actually on the plants as you spray them, and the detergent'll break down before any other insects meet it. But whether that would be as safe when you're actually watering the base of the plant with it rather than just misting the leaves, I'm not so sure. Dilution levels must be a factor too, I suppose.

[a-llusive.livejournal.com]

I've read elsewhere that detergent isn't such a good idea, so abandoned using it. They suggested its the vigorous water of the spray that is of help rather than the detergent anyway.

I'd suggest an arrangement with an accessible valve so that when you clean the shower more aggressive cleaning chemicals go out the 'old' way and you only have to consider regular toiletries which are probably adetergent-level problem, depending on your plants.

[undyingking.livejournal.com]

Mm, that could work, it could just be a valve on the downpipe diverter.