It had been estimated homes could be using up to 190 litres per person per day, but it has emerged that 93% of households are only using about 250 litres per day.
The average household contains three people according to CSO figures, so that means we are using just over 80 litres per person.
However, leaks remain an enormous problem on the wider water network, with an average of 47% of water being produced nationally disappearing into the ground through leaks.
The future of Irish Water will be one of the key issues in the formation of the next Government, with Fianna Fáil stating it plans to scrap the controversial utility.
In Co Cork, 57% of drinking water produced is disappearing in leaks. In Roscommon it stands at 68%. In Mayo, 58% is lost, and in Dún Laoghaire, it stands at 50%.
According to Irish Water, 7% of domestic customers have significant problems with leaking pipes and are using an average of 1,500 litres of water per day — nearly eight times more than the average household.
Irish Water is blaming century-old homes with extensive lead piping and “quickly built” Celtic Tiger houses for the lion’s share of such problems.
“There is one old house that we came across in Ringsend in Dublin that was leaking enough water to supply a big town,” said Irish Water conservation specialist Kate Gannon.
Irish Water also revealed that in the early 2000s, up to €100m was spent on installing district water meters in local authority areas.
However, not a cent was allocated in current Department of Environment spending towards maintenance, and when Irish Water examined the meters in 2014, 50% were not working.
Ms Gannon said Irish Water replaced 500km of aged and broken piping last year. It wants to spend another €135m on finding and fixing domestic leaks by 2021 and €300m replacing the leaking pipe network.
“The conservation team have developed a submission for the regulator on how to overhaul water between 2017 and 2021. We want to reduce leakage to a national average of 38% by 2021. By reducing it by 1% to 2% per year, this will conserve about 30m litres of water a day, which is equal to the water needs of Wicklow,” said Ms Gannon.
At the moment its focus is on domestic leaks, as due to data coming from meters, it can immediately detect high water usage and water flowing all night long, which usually indicates a leak.
“We will then contact you and ask about any plumbing problems as 50% of such problems are internal. If there doesn’t seem to be obvious problems, we will then offer a leak investigator and to fix the initial leak as part of our ‘first fix’ programme.”