The Expert Commission established to examine water charges could conclude that some form of charge may be required to guarantee Ireland meets its legal obligations under EU directives.

The report of the Commission is still being finalised and will set out a number of funding options for water services when it is presented to an Oireachtas Committee in the next fortnight.

The topic has been described by ministers as the most divisive issue in this Dáil, with the future or ending of water charges likely to pose one of the biggest challenges yet for the minority Government.

The exact scale of that challenge will become clearer once the Commission, which has been given the task of identifying funding models for domestic public water services, reports.

One option it will outline is a charge calculated on each cubic meter of water consumed.

However, there would be a free water allowance for all households and a significant one for families.

This would mean the final charge would, in the words of one source, be "modest".

It is believed such a model would guarantee the country met all legal obligations set out in European Union directives.

Other options, including the abolition of charges, will also be detailed in the report.

It is expected the Commission will have further meetings in the days ahead before finalising the report.

The findings will be considered by a special Oireachtas Committee made up of 16 TDs and four Senators which is due to be established next week.

Ultimately the future of water charges is likely to be decided by a Dáil vote next March.

"The suggestion that the Expert Water Commission may recommend water charges must go down as the least surprising news of the year," said Paul Murphy, of the Anti-Austerity Alliance.

He also warned: "If any attempt is made to re-introduce water charges, they [the Government] will be met by a renewed campaign of protest and non-payment and will pay an enormous political price."

To date the eight-person Commission led by former Labour Court Chairman Kevin Duffy has cost €280,000.

This includes costs for research and administrative support staff.

The members of the expert commission will get €3,000 each for their work and the chairman will be paid €7,500.