A series of flaws in Irish Water's plan for charging for water use have been identified.
Irish Water has confirmed that there will be no way to monitor how many occupiers are in one house.
In essence a house with multiple occupancy ultimately could claim to be a single person household, and there is no way for Irish Water to check.
"The system is based on self-declaration," a spokesperson for Irish Water told the Herald.
And the new cap arrangement outlined by the Government identified that a childless couple living together will pay 33pc more than two single adults living alone.
A single adult household will pay no more than €60 under the cap arrangement and once the €100 grant is taken into account. Households with two adults, regardless of the number of children, will pay €160 per year under the arrangement.
But two adults living alone will pay just €120, €40 (33.3pc) less than a couple using the same amount of water.
A representative for Irish Water said that there was no discrimination against childless couples.
"The Government has made a policy decision that water for children is free," the spokeswoman for Irish Water told the Herald.
Another flaw in the system relates to the €100 'water conservation grant' which will only be refunded once the annual bill has been paid. Households must hand over the full €260/€160 before they receive the €100 grant, paid back into their bank accounts by the Department of Social Protection.
This detail was revealed as the largest landlord organisation in the State has indicated that it will not cooperate with plans to oblige landlords to hand over deposits belonging to tenants who refuse to pay.
The Irish Property Owners' Association (IPOA) has described the Government's proposals as "shocking", "impossible" and "unacceptable".
The IPOA also said it is "horrified" at proposals that would see landlords inhibited from taking on new tenants until previous bills were settled.
The two key measures outlined by Environment Minister Alan Kelly are as follows:
l On the changeover of a tenancy, the registration of a new tenant with Irish Water would be conditional on all water charge arrears being discharged.
l Landlords whose tenants refuse or fail to pay would be entitled to withhold deposits and then required to hand it over to Irish Water.
IPOA information officer Margaret McCormick indicated that landlords will not comply.
"These proposals are impossible," she said. "We cannot be responsible for our tenants' bills."