Only those who have meters can face charges for using an 'excess' of water
Two in every five households are likely to escape any charge for using 'excessive' amounts of water because their homes are not fitted with a meter.
Just 891,500 homes have been fitted with meters, or 58pc of the 1.522 million drawing water from public supplies, figures from Irish Water show. Some 620,000 homes are unlikely to be hit with a bill, because their consumption cannot be measured.
This calls into question the fairness of the proposed system, under which homeowners will be hit from July 2019 with a levy for using excessive amounts of water, based on 1.7 times average use.
The introduction of an excess charge is widely seen as an effort to placate the European Commission, which has threatened to take enforcement action against the State for failing to introduce a charge under the 'polluter pays' principle.
The Government is taking its lead from the Expert Commission on Water and the all-party Dáil Committee on the Future Funding of Domestic Water Services, which both recommended that households found to be wasting water should be penalised.
But big questions remain as to how the system will operate and whether it is fair.
Irish Water will monitor usage from next January for 12 months and those found to be using a "wasteful" amount will be given six months to either reduce consumption or repair leaks.
If they fail to do so, they will be billed for the excess amount of the 'average' used.
But the water regulator, the Commission for Energy Regulation (CER), has said that if households do not have a meter, then their usage cannot be accurately measured, prompting questions as to why the Government is following this particular path.
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In correspondence to the Dáil committee, it also said that "equity and acceptance" had to be considered in the design of any excessive charging system - something which appears to have been forgotten. It would suggest the Government is hoping the European Commission will buy the argument that this is a 'polluter-pays' system.
The metering programme ended without any installation in an estimated 250,000 apartments and thousands of homes where it was technically difficult to do so, as well as in many homes in areas where public demonstrations took place. There have been suggestions that district or bulk meters, which measure water entering large areas, could be used to pinpoint leaks and identify homes using large volumes.
But Irish Water says that in the absence of domestic meters, the only way to locate homes with leaks is by sending operators around the area with sounding sticks, which would pick up the sound of flowing water.
Managing director Jerry Grant highlighted the problems with this approach to the Dáil committee.
He said that under the current system, around 6,000 leaks were found every three months.
"If we were to try to do that with operators with sounding sticks… we obviously would not get anywhere close to that figure," he said, adding that it would be "lucky to find a number in the hundreds" and that crews would be diverted from finding larger leaks in the public system.
The CER has not started work on deciding what the allowance of water should be and what tariff should be applied to 'wasteful' users. It is expected to complete an extensive public consultation before deciding, and will no doubt be informed by Government policy.
Currently, the charge is set at €3.70 per 1,000 litres but this includes a hefty government subsidy to cover the costs of producing the water. If the real cost of treating water is applied, it's likely to be far higher.
There are more questions than answers as the water debacle continues. Refunds totalling €173m will be made to households by year-end and Irish Water will also receive €114m to compensate for the loss of charges.
The near-€300m bill is the price of the deal with Fianna Fáil to prop up the Government - but it appears that only those with a meter will bear the brunt of any back-door return to bills.