The Irish Water (meters) thread


No, it gets reduced until the issue is addressed. By reducing the pressure the house still has a water supply.


I’ll decide what points I think are worth addressing and which ones aren’t, thanks. You do the same and it’ll work out fine.


This was posted less than 5 hours ago :angry:

post about the topic not each other


In an attempt to keep this thread on topic, let’s have a look at why new dwellings should incorporate Rainwater Harvesting.

Let’s assume the dwelling is a Semi D with a rainfall catchment area of 100m2, and that the roof has a tile finish. When trying to calculate the amount of water that can be harvested there are a load of different factors that need to be considered ranging from the location, the roof type, how the water is used in the house, the size of the tank etc.

Our example is in Lucan and it has an annual rainfall of about 700mm per annum. Of course this doesn’t tell us anything useful about how useful that rainfall is for ‘harvesting’. If all that rain fell in the winter it wouldn’t be feasible to store it for the summer. Thankfully the rainfall in Lucan, and the rest of the country is distributed reasonably well across the year.

Let’s take a year at random: 2004, and look at the rainfall across the year. That year there was about 760mm of rain. The chart below shows the daily rainfall amounts.

Now let’s assume that the household consists of 2 adults and 2 children. Assuming fairly normal water consumption patterns they use 420 Litres per day (L/day), a total of 150m3/annum. Of this water consumption 170 L/day is used for tasks that you could substitute for rainwater, namely the washing machine and flushing the toilet. The remaining 250 L/day have to be supplied with treated water.

A rainwater harvesting system diverts rainfall to a holding tank, and obviously the larger the tank then the more rainfall it can store, but the larger tank will have a higher cost so it’s necessary to find a balance.

In this example we will assume a 2000 Litre tank and then apply the water usage pattern to our rainfall chart. We also have to account for the amount of roof evaporation which is dependent on the roof type and the type of rainfall event. The following chart shows the water level in the water storage tank across the year.

The red parts on the chart show when there wasn’t sufficient rainwater storage to meet the needs of the house. During these periods the water from the mains system would be used automatically.

A total of 46m3 of rainwater was used in the house which under a water charging system would result in a 41% saving in the household bill. The cost of installing a system such as this in a new build unit would be €700-900.


Completely agree Coles. Rainwater harvesting should be used much more than it is. Of course if the government is going to deliver free unlimited treated water direct to my home there is no incentive for me to pay anything to have a rainwater harvesting system.

The government would have to pay for it in full. But you have to wonder if that would be a good return for the government on the €900 (or more to retrofit). Presumably that money would be better spent fixing leaks in the existing system?


@Coles2; are you using water harvesting as an argument for or against water charging here?
In other threads you state that new build estimates are overstated so what meaningful impact do you think this would have on the consumption of potable water in the state as a whole.
you also want the government to engage in building of social housing. If they build that housing do you think it will be standalone houses or Semi-Ds with sufficient roof or multi-unit development with insufficient roof area to collect water.


I was in favour of water charges when they were initially announced, but it quickly became apparent that FG weren’t prepared to keep the utility in Public ownership and that it was just a way to undo the progressive nature of our taxation system and transfer taxation from the richest to the poorest. I’m not in favour of that.

If the ownership of the utility was safeguarded and the structure of the water charges was progressive (maybe on property value so that it was in effect a form of Rates), then it could work… BUT!.. while on the face of it water metering makes sense, the cost of installing and maintaining meters makes it unfeasible, let alone the cost of administrating it. In order to pay for the continuous metering system you have to ramp up the cost of the water. It’s a dumb idea.

That’s a very good point. There is a real limit to how much water can be collected off a roof. Comparing the same figures for a 900 sqft terraced house show that the amount of rainwater consumed in a year would be down from 46’000 Litres to 39’500 Litres. You can try to store more water with a larger tank to account for the smaller roof, but it gets to the stage where there’s little additional benefit despite the bigger tank. Clearly the more roof you have the more you benefit from it, and in an apartment you get no benefit from it at all.

There are other stumbling blocks with RWH (and anyone interested in the electricity Microgeneration debate will probably spot them). While anyone on an individual basis can avoid a lot of water charges with RWH, the utility system still needs to be able to meet their needs in times of drought. If the government were to incentivise a widespread RWH scheme then they would need to design it so that the storage tanks were sufficient to limit the impact of droughts. Easily done, but important.

It is also worth noting that the Dublin region has the lowest amount of rainfall in the country and the figures are a lot more favourable in other towns and cities.

If anyone is interested in seeing the charts for any particular area of the country I will post them up. If the aim of the game is to conserve drinking water then RWH works. If the aim is to reduce the tax burden on the wealthy then you need an expensive metering system.


The variable cost of water is low - the fixed cost [physical infrastructure/salaries for treatment plant employees] is high. This should be part of any calculation.

Expecting a subset of people buying new homes to effectively subsidies others by additional pointless investment is simply unfair. Just like putting a levy on electricity for apartment dwellers to subsidise PV for SUV driving suburbanites :imp:

then there’s the environmental copst of all those plastic tanks :unamused:
Sounds just like a Green Party wheeze


Privatisation of Irish Water possible, Dáil hears, Irish Examiner


Under a water charges system people who can afford to install Rainwater Harvesting will do it simply because it makes very good economic sense. Same is true with PV and a TeslaWall. That future can’t be avoided so we may as well find ways to accommodate it.


You might panic if you had to compare the waiting times for a colonoscopy in a Public Hospital compared to going Private.


Coles you should have tendered for the children’s hospital.

Anyway I was looking into this a couple years ago for what was a new build, it was 4-5k. Water charges were anticipated at the time and for far higher than they turned out to be, but even so there was no way I’d ever get the money back, so I quickly gave up on the idea - 1 second after hearing the quotes. … 2055992759
Everyone on that boards thread got similar figures, if you go to and price a 5000L tank you’ll see you’re looking at 1k plus for that bit of moulded plastic - I have no idea why.

Clearly it should be cheaper for someone building several units but 80% off the full price isn’t going to happen.

Ignoring Ireland and our nonsense taxes and costs look at the first result if you google “rainwater harvesting uk cost”.

According to the UK Rainwater Harvesting Association the cost of an average, fully functioning domestic system will be between £2,000 and £3,000 excluding the price of installation.


Do you want me to send you a parts list so you can do it yourself for less than €700?


No response. Oh well.

For anyone else interested, I’ll outline the important bits.

There is no need for the tank to be suitable for ‘potable’ water, so the tank will cost about €300 for 1600 Litres. A potable tank would add abut €50. The water gets diverted to the tank by a diversion/filter kit that will cost €80 for a good quality system. The best way to plumb the system is to have it piped directly to the toilet and washing machine. The best type of pump to use is a pressure controlled pump similar to the type used in camper vans and mobile home. A very good quality pump will cost €75 with another €15 for a strainer and floating inlet. If you wanted to reducing the cycling of the pump you could install a pressure vessel after the pump (€35). The tank should also have a top up valve to supply mains water to the tank for times when the tank is empty. This valve system will cost €90-€100. Add a 12v transformer for the pump, a few fittings, pipe and bits and pieces and the total cost is still under €700.


Rainwater harvesting
Rainwater harvesting makes zero sense in Ireland. Even if you were building every house from scratch tomorrow.

There is monopoly provision of treated, piped water to every urban household in the country (as there is in most countries). The fixed cost of the network is very high, the marginal cost per unit pumped through it is pretty low. Rainfall is not scarce in Ireland, although treatment does have a unit cost.

There is simply no benefit in putting in place a system of harvesting and a parallel system of plumbing in every house to deal with a quarter of a household’s needs. Even if the parts were €700 and it magically appeared fully installed for free in your house it would not make sense.

Second, even harvested water used for washing needs to be treated - and AFAIK treatment actually costs more than supply!

Some people will go to absurd analytical lengths to justify a position which is ideological.

Fears about privitisation of water infrastructure
May play well on certain corners of facebook but it is a total nonsense to suggest that anyone has seriously had any intention of allowing the ownership of water infrastructure to pass into private hands.

If you care enough google the Water Services Act 2014 and find the part that obliges the government of the day to conduct a plebiscite before such an act could even be contemplated.


I don’t agree with that. With a weak incompetent Government the top management layers of a public owned utility would seek to bring it private to enrich themselves…or some variant of it where the service which can’t be brought private just becomes a contract awarder to private companies for the services which are delivered under its name.


if you have a few spare plastic barrels you can put them under your gutters and use it for watering your flowers. Other than that - spot on.

It’s akin to people moaning about electricity standing charge. If you don’t want the security of a reliable mains backup you know what to do…


My standing charge cost nearly as much as my actual consumption. Did I have no right to complain?


My point is about the costs of maintaining the network. There’s a high fixed cost. Even if you cover your house in PV. That cost is still there.


Then undermine your position by bringing in an indefensibly high standing charge for Electricity.