WATER charges are unlikely to be as low as the €200 per family Tanaiste Joan Burton pitched last week, according to senior government officials.
Four departments are "stress-testing" a new two-tier water charge draft regime which is hoped will unlock the debacle that has dogged the Government for the past six months.
But serious doubts persist in government circles about the charges being as low as pledged by Ms Burton, who said a family of four would pay less than €200 once allowances and supports were taken into account.
One government source last night said the suggestion that a single-person household could pay a little as €80 per year appeared "unlikely".
The same doubt was expressed about speculation that larger households would pay as little as €200 per year. The source said the difficulty remained the level of customer revenue going to Irish Water.
"We need to ensure that Irish Water can borrow under EU rules as a semi-state company without adding to the national debt. If charges are pitched too low, that will not happen," the source told the Irish Independent.
The two-tier system means that a lower charge will apply to single-person homes including widows and lone parents. A second, higher, fixed charge will apply to larger households, including families.
Discussions between officials from the Departments of Finance, Public Expenditure, Environment and Communications also focus on the prospect of fixing the charges until 2017 or 2018.
The most difficult part of the discussions centres on the actual rate to be applied. Ministers gathered at the weekly Cabinet meeting today are thought unlikely to engage in any prolonged discussion on the matter and are expected to leave the senior officials to continue their work.
The ministers from the four departments concerned are due to meet tomorrow and consider an updated progress report.
The new charge regime is aimed at encouraging people to register with Irish Water, as those who fail to register face a higher fixed rate.
At the same time, houses that have meters, and where less than the fixed amount of water is used, will have the opportunity to further reduce their bill.
This move is seen as an effort to incentivise people to accept meters. Officials hope these positive incentives will prove more effective than threats, withdrawn last week, to reduce non-payers' water supply to a trickle.
As things stand, officials expect a final agreement on the package after next Tuesday's Cabinet meeting. The Government still hopes that once people see modest charges, the crisis can be defused.