water havesting 20 September 2017 at 10:05PM in Green & Ethical MoneySaving 8 replies 1.7K views

ard123en

following on from the solar we are getting installed

Im wondering about reducing our water usage by holding rain water in a header tank to flush the toilet

has any one on here done this before ?

ASavvyBuyer

ard123en wrote: »

following on from the solar we are getting installed

Im wondering about reducing our water usage by holding rain water in a header tank to flush the toilet

has any one on here done this before ?

Yes, we do it for one of our toilets. We are on a water meter, so it saves paying for quite a lot of water. Currently only pay £15 a month for water.

If you do it, you have to make sure that mains water & harvested water can't mix. So, just feed the cistern with harvested water and disconnect the mains water. We have just over 400 litres of water storage for the toilet, plus another 600 litres for the garden & backup; which is usually enough, here in Wales as it regularly gets topped up with fresh rain.

EricMears

We also run our WCs on rainwater.

Most of roof drains via a single downpipe which can be turned to send water into basement storage tanks or to a soakaway system.

From the 4x1000litre storage tanks I pump water to 2x250litre header tanks in attic. It usually needs approx. 100 litres per day to be pumped.

From the header tanks, a pipe leads to our WCs and on to an outside tap. The tap can be used for filling watering cans etc but primary purpose is to drain out any airlocks if header tanks get empty.

WCs are almost our only use of rainwater - but the average household uses approx. a third of its water consumption to flush WCs so arguably I'm getting a one third discount on metered water bills.

Cardew

There are many posts on MSE about water harvesting - both rain water and 'grey water'.

The installations range from 'Rolls -Royce' solutions costing £thousands to a simple DIY setup.

EricMears

There's a side benefit to using rainwater for WCs which may not be immediately obvious to some.

We had an early morning phone call from Severn Trent (or their 'robot') this morning advising that there would be no water supply to our area till at least lunch time.

That won't affect our W.C. usage in any way. However, any neighbours who have their house plumbed in what seems to be the conventional way these days may be in for a nasty surprise if they're the third person to use their lavatory today !

I've no idea when or why feeding W.C.s from a header ceased to be normal but in circumstances like today's it's likely to cause a great deal of inconvenience. Fetching a bucket of water from the garden pond (IF you've got one) to flush the W.C. won't be a lot of fun.

ard123en

Thanks have ordered a diverter and a small pump today will be trying a proof of concept this weekend

Andy_WSM

I fitted 3,000L of water storage 10 years ago that flushes my WCs and feeds the washing machine. It's worked faultlessly throughout and made a significant reduction to my water bills. My system uses a pump in the loft that charges a pressure vessel and kicks in to recharge whenever a toilet is flushed or the washing machine used. I also have an outside tap on the system, but only really use it to fill a watering can and water the houseplants - or maybe occasionally hose down the patio.

ard123en

What are you using in the way of filtering when using it for washing ?

Andy_WSM

A floating strainer on the pump (so it picks up water away from the bottom of the tank, thus avoiding sediment) and a 10 micron spun filter in the loft which I change once a year (or less!).