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Want to cut your water bill in half? I've the secret, just harvest your rainwater

You'd think someone would have mentioned collecting rainwater off the roof and using it to flush the toilet.

I mean, we're in Ireland. It rains 150 days a year on the east coast and 225 days a year in parts of the West.

We may not have oil, but we are the Sheikhs of rain. It's the only bloody natural resource we have. Oh, except wind. We have that too.

But just like you have to catch the wind with a proper turbine if you want to do more than dry your clothes, you have to catch the rain with a harvester if you want to do more than water the garden.

A proper rainwater harvester collects all the rain off your roof, filters it, protects it from rhodents and stagnation and pumps it back to where you need it.

It looks like an oil tank sitting in your back yard or you can hide it underground for a bit more money.

Your average harvester won't make water clean enough to drink but you can use it to flush the toilets and run the washing machine as well as having outside taps for hosing down the car and watering plants.


Good rainwater harvesting systems switch to mains water if the rainwater runs out. That doesn't happen too much in Ireland. You're more likely to see a threat to your mains water.

A rainwater harvester gives you your own back-up supply if mains water supply is threatened. It's a bit like having your own water generator.

And when it buckets, harvesters come into their own again, because they not only make use of the water, they help save us from the floods caused by too much run-off.

We installed a harvester about five years ago when we were doing a Celtic Tiger job on the house.

It cost about €5k all told, by the time it was installed, but I've seen quotations from €2k to €4k and the cost can be halved in a new-build because half the cost is getting machinery on site.

We knew we were going to be in our house a long time and we thought we should do a sustainable build while we were at it. It was always bonkers to be flushing good drinking water down the toilet.

We expected water charges to come in earlier, but over-priced as it was, the harvester will still pay for itself eventually.

I've got three teens and a preteen who are going to bust their children's free water allowance and then become adults who will probably live at home for a very long time.

Even at today's rates, we'll be paying over €600-a-year and that will go up. A water harvester only used for toilets and the washing machine will typically cut your bill in half. I'm going to hook ours up to the dishwasher and the showers which should cut my bill by two-thirds.

It's been reported the Government's planning to make harvesters standard issue in new builds from next year. But why not support a scheme to "retrofit" houses with rainwater harvesters, the way we insulated houses?

Bought in bulk and perhaps fitted in group schemes, the price could be brought right down.

Payback times of seven years are routinely reported and that's not bad when you consider the years and years of free water you could have afterwards.

You'd think the Government would step in with grants or financing, perhaps delivered through Irish water. I found several Irish manufacturers of these rainwater harvesters, so they'd be supporting Irish jobs.


And, of course, the plumbing contractors who gained an expertise in installing the harvesters would get a bit of much-needed work.

So why won't the Government support us to use the water which falls onto our houses from the skies?

Isn't the whole point of water charges to make us value water and not waste it?

Or have I missed something?